Relevant bibliographies by topics / PHBV

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Academic literature on the topic 'PHBV'

Author: Grafiati
Published: 4 June 2021
Last updated: 4 May 2024

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Journal articles on the topic "PHBV"

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Feijoo, Patricia, Kerly Samaniego-Aguilar, Estefanía Sánchez-Safont, Sergio Torres-Giner, Jose M. Lagaron, Jose Gamez-Perez, and Luis Cabedo. "Development and Characterization of Fully Renewable and Biodegradable Polyhydroxyalkanoate Blends with Improved Thermoformability." Polymers 14, no. 13 (June 21, 2022): 2527. http://dx.doi.org/10.3390/polym14132527.

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Poly(3-hydroxybutyrate-co-3-valerate) (PHBV), being one of the most studied and commercially available polyhydroxyalkanoates (PHAs), presents an intrinsic brittleness and narrow processing window that currently hinders its use in several plastic applications. The aim of this study was to develop a biodegradable PHA-based blend by combining PHBV with poly(3-hydroxybutyrate-co-3-hydroxyhexanoate) (PHBH), another copolyester of the PHA family that shows a more ductile behavior. Blends of PHBV with 20% wt., 30% wt., and 40% wt. of PHBH were obtained by melt mixing, processed by cast extrusion in the form of films, and characterized in terms of their morphology, crystallization behavior, thermal stability, mechanical properties, and thermoformability. Full miscibility of both biopolymers was observed in the amorphous phase due to the presence of a single delta peak, ranging from 4.5 °C to 13.7 °C. Moreover, the incorporation of PHBH hindered the crystallization process of PHBV by decreasing the spherulite growth rate from 1.0 µm/min to 0.3 µm/min. However, for the entire composition range studied, the high brittleness of the resulting materials remained since the presence of PHBH did not prevent the PHBV crystalline phase from governing the mechanical behavior of the blend. Interestingly, the addition of PHBH greatly improved the thermoformability by widening the processing window of PHBV by 7 s, as a result of the increase in the melt strength of the blends even for the lowest PHBH content.
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Pustan, Marius, Corina Bîrleanu, Adorján Cristea, and Horia Leonard Banciu. "Nanotribological Investigation of the Poly(3-hydroxybutyrate) Films Manufactured from the Storage Polyesters Produced by Halomonas elongata DSM 2581T." Engineering Proceedings 4, no. 1 (April 14, 2021): 29. http://dx.doi.org/10.3390/micromachines2021-09564.

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Poly(3-hydroxybutyrate) (PHB) is a natural and biodegradable storage polyester, produced by numerous bacteria, which is considered a potential substituent for conventional plastics in the packaging industry. The improvement of the PHB material lifetime often involves mechanical and tribological characterization, which can be accurately performed on thin films. In this study, we aimed at the evaluation of the tribological properties, such as adhesion force, friction coefficient and wear resistance, of different polyester films, fabricated via the solvent casting method. Three polyester films were designed in this study, each containing 1% w/v constituents as follows: a PHBh film prepared out of the PHB, extracted from the extremely halotolerant bacteria, Halomonas elongata DSM2581T, a PHBc film fabricated using a commercially available PHB, and a PHBVc film generated using the commercial poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV). The spectroscopy-in-point of AFM was used for adhesion force measurement based on multiple tests performed in a matrix, and the AFM lateral operating mode was applied for friction analysis under a controlled normal load. The fabricated PHBh film presented a thickness between 5 and 7 µm, a lower adhesion force (14 nN) as well as a smaller friction coefficient (0.15) compared to the PHBc and PHBVc. The tribological investigations of PHBh film revealed a biodegradable material with low roughness, as well as small adhesion and friction forces. Further optimization can be performed for the improvement of the PHBh film by copolymerization with other polymers, polyesters, and reinforcers, thus generating a feasible material with advanced tribo-mechanical features.
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Deng, Wei, Yingjie Di, Jingxuan Cai, Yueyang Chen, and Shuzhong Yuan. "Target-Site Resistance Mechanisms to Tribenuron-methyl and Cross-resistance Patterns to ALS-inhibiting Herbicides of Catchweed Bedstraw (Galium aparine) with Different ALS Mutations." Weed Science 67, no. 2 (December 18, 2018): 183–88. http://dx.doi.org/10.1017/wsc.2018.70.

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AbstractCatchweed bedstraw (Galium aparine L.) is a problematic dicot weed that occurs in major winter wheat (Triticum aestivum L.) fields in China. Tribenuron-methyl has been widely used to control broadleaf weeds since 1988 in China. However, overuse has led to the resistance evolution of G. aparine to tribenuron-methyl. In this study, 20 G. aparine populations collected from Shandong and Henan provinces were used to determine tribenuron-methyl resistance and target-site resistance mechanisms. In dose–response experiments, 12 G. aparine populations showed different resistance levels (2.92 to 842.41-fold) to tribenuron-methyl compared with the susceptible population. Five different acetolactate synthase (ALS) mutations (Pro-197-Leu, Pro-197-Ser, Pro-197-His, Asp-376-Glu, and Trp-574-Leu) were detected in different resistant populations. Individuals heterozygous for Pro-197-Ser and Trp-574-Leu mutations were also observed in a resistant population (HN6). In addition, pHB4 (Pro-197-Ser), pHB7 (Pro-197-His), pHB8 (Pro-197-Leu), pHB5 (Asp-376-Glu), and pHB3 (Trp-574-Leu) subpopulations individually homozygous for specific ALS mutations were generated to evaluate the cross-resistance to ALS-inhibiting herbicides. The pHB4, pHB7, pHB8, pHB5, and pHB3 subpopulations all were resistant to sulfonylurea, pyrazosulfuron-ethyl, triazolopyrimidine, flumetsulam, sulfonylamino-carbonyl-triazolinone, flucarbazone-sodium, pyrimidinyl thiobenzoate, pyribenzoxim, and the imidazolinone imazethapyr. These results indicated the diversity of the resistance-conferring ALS mutations in G. aparine, and all these mutations resulted in broad cross-resistance to five kinds of ALS-inhibiting herbicides.
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Kim, Sinil, Byeongsuk Ha, Minseek Kim, and Hyeon-Su Ro. "Investigation of Mating Pheromone–Pheromone Receptor Specificity in Lentinula edodes." Genes 11, no. 5 (May 4, 2020): 506. http://dx.doi.org/10.3390/genes11050506.

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The B mating-type locus of Lentinula edodes, a representative edible mushroom, is highly complex because of allelic variations in the mating pheromone receptors (RCBs) and the mating pheromones (PHBs) in both the Bα and Bβ subloci. The complexity of the B mating-type locus, five Bα subloci with five alleles of RCB1 and nine PHBs and three Bβ subloci with 3 alleles of RCB2 and five PHBs, has led us to investigate the specificity of the PHB–RCB interaction because the interaction plays a key role in non-self-recognition. In this study, the specificities of PHBs to RCB1-2 and RCB1-4 from the Bα sublocus and RCB2-1 from the Bb sublocus were investigated using recombinant yeast strains generated by replacing STE2, an endogenous yeast mating pheromone receptor, with the L. edodes RCBs. Fourteen synthetic PHBs with C-terminal carboxymethylation but without farnesylation were added to the recombinant yeast cells and the PHB–RCB interaction was monitored by the expression of the FUS1 gene—a downstream gene of the yeast mating signal pathway. RCB1-2 (Bα2) was activated by PHB1 (4.3-fold) and PHB2 (2.1-fold) from the Bα1 sublocus and RCB1-4 (Bα4) was activated by PHB5 (3.0-fold) and PHB6 (2.7-fold) from the Bα2 sublocus and PHB13 (3.0-fold) from the Bα5 sublocus. In particular, PHB3 from Bβ2 and PHB9 from Bβ3 showed strong activation of RCB2-1 of the Bβ1 sublocus by 59-fold. The RCB–PHB interactions were confirmed in the monokaryotic S1–10 strain of L. edodes by showing increased expression of clp1, a downstream gene of the mating signal pathway and the occurrence of clamp connections after the treatment of PHBs. These results indicate that a single PHB can interact with a non-self RCB in a sublocus-specific manner for the activation of the mating pheromone signal pathways in L. edodes.
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Abbasi, Maryam, Dikshya Pokhrel, Erik R. Coats, Nicholas M. Guho, and Armando G. McDonald. "Effect of 3-Hydroxyvalerate Content on Thermal, Mechanical, and Rheological Properties of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Biopolymers Produced from Fermented Dairy Manure." Polymers 14, no. 19 (October 3, 2022): 4140. http://dx.doi.org/10.3390/polym14194140.

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Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with various 3-hydroxyvalerate (3HV) contents biosynthesized by mixed microbial consortia (MMC) fed fermented dairy manure at the large-scale level was assessed over a 3-month period. The thermal, mechanical, and rheological behavior and the chemical structure of the extracted PHBV biopolymers were studied. The recovery of crude PHBV extracted in a large Soxhlet extractor with CHCl3 for 24 h ranged between 20.6% to 31.8% and purified to yield between 8.9% to 26.9% all based on original biomass. 13C-NMR spectroscopy revealed that the extracted PHBVs have a random distribution of 3HV and 3-hydroxybutyrate (3HB) units and with 3HV content between 16% and 24%. The glass transition temperature (Tg) of the extracted PHBVs varied between −0.7 and −7.4 °C. Some of the extracted PHBVs showed two melting temperatures (Tm) which the lower Tm1 ranged between 126.1 °C and 159.7 °C and the higher Tm2 varied between 152.1 °C and 170.1 °C. The weight average molar mass of extracted PHBVs was wide ranging from 6.49 × 105 g·mol−1 to 28.0 × 105 g·mol−1. The flexural and tensile properties were also determined. The extracted polymers showed a reverse relationship between the 3HV content and Young’s modulus, tensile strength, flexural modulus, and flexural strength properties.
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Yun, So Hee, Ga Young Jun, Kwan Han Yoon, Yong Soon Park, Young Jin Kim, Inn Kyu Kang, and Oh Hyeong Kwon. "Co-Electrospinning of Microbial Polyester/Gelatin and their Interaction with Fibroblasts." Key Engineering Materials 342-343 (July 2007): 201–4. http://dx.doi.org/10.4028/www.scientific.net/kem.342-343.201.

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Biodegradable poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibrous matrix containing gelatin was fabricated by electrospinning method. The average diameter of electrospun PHBV/Gelatin (1:1) nanofibers was 600 nm determined by FE-SEM. ATR-FTIR and ESCA measurements were used to confirm the presence of gelatin in PHBV/Gelatin nanofibers. Human fibroblasts' behavior on PHBV/Gelatin nanofibrous matrix has been investigated. Fibroblasts were well attached on the surface of control PHBV and PHBV/Gelatin nanofibers. Initial cell attachment on PHBV/Gelatin nanofibers was higher than that of control PHBV nanofibers. Gelatin has many RGD moiety that mediate cell attachment. From this reason, initial cell attachment increased on the surface of PHBV/Gelatin nanofibers. From the results, coelectrospinning of PHBV and gelatin is a promising method for tissue engineering scaffold.
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Guo, Yong, Li Wang, Yuxia Chen, Panpan Luo, and Tong Chen. "Properties of Luffa Fiber Reinforced PHBV Biodegradable Composites." Polymers 11, no. 11 (October 27, 2019): 1765. http://dx.doi.org/10.3390/polym11111765.

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In this study, composites of poly (hydroxybutyrate-co-valerate) (PHBV) with untreated luffa fibers (ULF) and NaOH-H2O2 treated luffa fibers (TLF) were prepared by hot press forming. The properties of luffa fibers (LFs) and composites were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and other analysis methods. Results showed that pre-treatment effectively removed pectin, hemicellulose, and lignin, thus reducing the moisture absorptivity of LFs. The flexural strength of TLF/PHBV was higher than that of ULF/PHBV. With 60% LF content, the flexural strengths of ULF/PHBV and TLF/PHBV reached 75.23 MPa and 90.73 MPa, respectively, 219.7% and 285.6% more than that of pure PHBV. Water absorptivities of composites increased with increase in LF content. Water absorptivity of TLF/PHBV was lower than that of ULF/PHBV. The flexural strengths of composites decreased after immersion in water at room temperature. Meanwhile, flexural strength of TLF/PHBV was lower than that of ULF/PHBV. Pretreatment of LFs effectively improved the bonding between fibers and PHBV, resulting in enhanced and thus improved the moisture resistance of composites.
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Krikštanavičienė, Kira, Sigitas Stanys, and Vaida Jonaitienė. "Comparative Investigation of Mechanical–Physical Characteristics of Biodegradable and Non-Degradable Yarns." Autex Research Journal 14, no. 2 (June 1, 2014): 61–72. http://dx.doi.org/10.2478/aut-2014-0001.

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Abstract This article presents the results from investigations of tensile tests, absorbency test and degradation test of biodegradable and non- or partly biodegradable yarns produced from pure poly hydroxybutyrate-co-valerate (PHBV), poly (lactide acid) (PLA), isotactic polypropylene (iPP) polymers and their blends. The results indicate that mechanical-physical properties of PHBV are improved by adding PLA and iPP to PHBV. The main results indicate that the PHBV/PLA and PHBV/iPP (70/30) blends had better mechanical properties than pure PHBV, as well as improved immiscibility and the same or lower degradation in sodium chloride solution, respectively. The PHBV/PLA and PHBV/iPP blends showed a tendency for lower crystallinity and stiffness of the yarns, rendering them less stiff and fragile. The absorption tests showed that absorption dynamic process depends on the structure and raw materials of the yarns. The disinfectant in all samples is absorbed faster than blood. Research results showed that pure PHBV yarns have good hydrophobic properties, compared with pure PLA and iPP yarns. The use of additional PLA and iPP polymers changed the wetting behaviour of yarns. Absorption time of blended yarns in disinfectant liquid decreases and absorption time in the case of blood significantly increases in comparison with PLA and iPP yarns and decreases compared with PHBV yarns. The degradation tests (within 90 days in a solution of sodium chloride) showed that pure PHBV and PHBV/PLA blends degraded at different rates but with the loss of the same weight, while pure PHBV and PHBV/iPP blends degraded at the same rate, but PHBV/iPP blends had worse destruction results. Such improvements are expected to be important for the practical application of PHBV in some fields
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Zhou, Zhe, Hou Yong Yu, Mei Fang Zhu, and Zong Yi Qin. "Effects of Microcrystalline Cellulose on the Thermal Properties of Poly(3-hydroxybutyrate-co-3-hydroxyvalerate)." Advanced Materials Research 284-286 (July 2011): 1778–81. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.1778.

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The composites of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) with different microcrystalline cellulose (MCC) contents were prepared by a solvent casting method. The effects of MCC on the thermal properties of PHBV were studied by TGA and DSC. The DSC results showed that the melt crystallization temperature of the PHBV/MCC increased from 41.9 °C for PHBV to 59.8 °C for the composites containing 20 wt. % MCC, which indicated that the crystallization of PHBV became easier with the addition of MCC. It also illustrated that the MCC could be used as an effective nucleation agent for the crystallization of PHBV. Moreover, it was found that the thermal stability of the PHBV/MCC composites increased compared with the neat PHBV.
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Wang, Lu, Chang Kun Ding, Hao Bo Shi, Bo Wen Cheng, and Wu Qiong. "Preparation and Properties of Bacterial Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) Fibers." Advanced Materials Research 335-336 (September 2011): 1477–80. http://dx.doi.org/10.4028/www.scientific.net/amr.335-336.1477.

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Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is biosynthetic aliphatic polyester with good biocompatibility and biodegradability. In this paper, PHBV biodegradable fibers were manufactured by melt-spinning, and the drawing procedure and heat setting of the fibers were applied. By X-ray diffraction, SEM and stress-strain measurements, the crystalline and mechanical properties of PHBV fibers were investigated. The results showed that β-form crystals were obtained in some PHBV fibers. Surface fibrillation phenomenon occurred in the oriented PHBV fibers. The tensile strength of PHBV fibers increased with increasing the draw ratio. The tensile strength of 10 times stretched PHBV fibers can reach 227 MPa.
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Dissertations / Theses on the topic "PHBV"

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Junior, Osvaldo Francisco de Souza. "Desenvolvimento e caracterização de blendas de PHBV e EVA com altos teores de acetado de vinila (VA)." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/18/18158/tde-01062017-082253/.

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O objetivo desse trabalho foi desenvolver e caracterizar blendas poliméricas dos copolímeros de poli(hidroxibutirato-co-hidroxivalerato) (PHBV) com poli(etileno-coacetato de vinila) (EVA) contendo altos teores de acetato de vinila (VA). Os teores de VA nos EVA utilizados foram de 65% (EVA65) e 90% (EVA90) em massa. Como as propriedades finais das blendas de PHBV, copolímero derivado de fonte renovável e biocompostável, com EVA, polímero de origem petroquímica e não biocompostável, são altamente dependentes do número de fases constituintes do sistema, esse trabalho investigou inicialmente a miscibilidade desses blendas. Assim, blendas contendo entre 10 e 90% (m/m) de EVA foram preparadas a partir do estado fundido em reômetro de torque e caracterizadas por calorimetria exploratória diferencial (DSC) e microscopia eletrônica de varredura (MEV). Os resultados da reometria de torque indicaram que o EVA65 sofreu degradação termomecânica (com ramificação e/ou reticulação das cadeias), enquanto que no PHBV predominou o processo de cisão. As blendas PHBV/EVA65 apresentaram duas transições vítreas e nítida separação de fases, em todas as composições, típicas de sistemas imiscíveis. Em contraste, o EVA90 não apresentou degradação nas condições de estudo. As curvas DSC das blendas PHBV/EVA90 apresentaram uma única temperatura de transição vítrea (Tg) cuja variação em função da fração em massa de cada componente foi prevista pela equação de Fox. As micrografias indicando a presença de uma única fase comprovam que as blendas PHBV/EVA90 são totalmente miscíveis em qualquer proporção. Após essa etapa, buscou-se avaliar a influência do teor de VA nas blendas PHBV/EVA. Para atingir esse objetivo, blendas contendo 5, 10, 20 e 30% (m/m) de EVA foram preparadas em extrusora dupla rosca co-rotacional interpenetrante e a influência do teor de VA na biodegradabilidade, morfologia e comportamento térmico e mecânico dessas blendas foi investigada por ensaio de biodegradação em solo, MEV, DSC, análise termo-dinâmico mecânica (DMA) e, ensaios mecânicos de tração e impacto. Além da influência sobre as transições térmicas dos polímeros mencionada anteriormente, os resultados de DSC mostraram que a temperatura de cristalização a frio (Tcc) e a entalpia de fusão (ΔHm) do PHBV aumentaram com o aumento do teor de EVA. Porém, o teor de VA e, consequentemente a miscibilidade das blendas, teve forte influência sobre a entalpia de cristalização a frio (ΔHcc) do PHBV. A presença do EVA65 reduziu significativamente os valores de ΔHcc, enquanto para as blendas preparadas com EVA90 esses valores foram superiores ao do polímero puro, sugerindo influência direta sobre a cinética de cristalização do PHBV. De uma maneira geral, as propriedades mecânicas em tração, tais como, resistência à tração e módulo elástico diminuíram com o aumento do teor de EVA, independentemente do teor de VA nas blendas. Entretanto, a deformação na ruptura foi altamente influenciada pelo teor de VA. Blendas PHBV/EVA65 apresentaram pequeno aumento na deformação na ruptura com o aumento do teor de EVA, provavelmente devido à fraca adesão interfacial entre seus os componentes. Já a deformação na ruptura de blendas PHBV/EVA90 contendo 30% (m/m) de EVA foi de 280%, muito superior à deformação na ruptura de 1,7% do PHBV. A taxa de biodegradação das blendas PHBV/EVA foi menor que a determinada para o PHBV. Apesar da baixa perda de massa determinada no PHBV e nas blendas PHBV/EVA após 180 dias de ensaio de biodegradação, foi possível observar que blendas PHBV/EVA65 apresentaram taxas de biodegradação superiores as apresentadas pelas blendas PHBV/EVA90. Além disso, blendas PHBV/EVA65 contendo altos teores de EVA apresentaram maiores taxas de biodegradação. Nas blendas PHBV/EVA90 as maiores taxas de biodegradação foram obtidas em composições contendo baixos teores de EVA. Esses resultados demonstraram que a miscibilidade afetou a biodegradabilidade das blendas PHBV/EVA de maneira negativa.
The aim of this work was to develop and characterize blends of poly (hydroxybutyrateco-hydroxyvalerate) (PHBV) and poly (ethylene-co-vinyl acetate) (EVA) containing high amount of vinyl acetate (VA). The VA amount in the EVA used here were 65% (EVA65) and 90% (EVA90) in mass. As the final properties of PHBV blends, a polymer derived from a renewable and biocompostable source with EVA, a polymer of petrochemical and non-biocompostable origin, are highly dependent on the number of constituent phases of the system. Therefore this work initially investigated the miscibility of these blends. PHBV/EVA blends containing 10 to 90% (m/m) of EVA were prepared from the molten state in a torque rheometer and characterized by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The results of the torque rheometry indicated that EVA65 chains underwent thermomechanical degradation with branching and / or crosslinking, while in PHBV the scission process predominated. The PHBV/EVA65 blends presented two vitreous transitions and distinct phase separation, typical of immiscible systems. In contrast, EVA90 showed no degradation in the study conditions. The DSC curves of the PHBV/EVA90 blends presented a single glass transition temperature (Tg) whose variation as a function of the mass fraction of each component was predicted by the Fox equation. The micrographs indicating the presence of a single phase prove that PHBV blends/EVA90 are totally miscible in any proportion. After this step, the influence of VA amount on the PHBV/EVA blends was studied. PHBV/EVA blends containing 5, 10, 20 and 30% (m/m) EVA were prepared in an interpenetrating co-rotational double screw extruder and the influence of VA content on the biodegradability, morphology and thermal and mechanical behavior of these blends was investigated by soil biodegradation test, SEM, DSC, dynamic mechanical analysis (DMA) and mechanical tensile and impact tests. In addition to the influence on the thermal transitions aforementioned, the DSC results showed that the cold crystallization temperature (Tcc) and the melting enthalpy (ΔHm) of PHBV increased with increasing EVA amount. However, the VA content and hence the miscibility of the blends, had a remarkable influence on the cold crystallization enthalpy (ΔHcc) of PHBV. The presence of EVA65 significantly reduced ΔHcc values, while for blends prepared with EVA90 these values were higher than that of pure polymer, suggesting a direct influence on PHBV crystallization kinetics. In general, mechanical tensile properties, such as tensile strength and elastic modulus decreased with increasing EVA content, regardless of the VA content in the blends. However, the deformation at rupture was highly influenced by the VA amount. PHBV/EVA65 blends exhibited small increase in the elongation at break with increasing EVA amount, probably due to the poor interfacial adhesion between their components. The elongation at break of PHBV/EVA90 blends containing 30% (m/m) of EVA was 280%, much higher than the elongation at break of 1.7% of neat PHBV. The biodegradation rate of PHBV/EVA blends was lower than that determined for PHBV. Despite the low loss of mass determined in PHBV and PHBV/EVA blends after 180 days of biodegradation test, it was possible to observe that PHBV/EVA65 blends had higher biodegradation rates than PHBV/EVA blends90. In addition, PHBV/EVA65 blends containing high EVA amount showed higher rates of biodegradation. In the PHBV/EVA90 blends the highest rates of biodegradation were obtained in compositions containing low EVA contents. These results demonstrated that the miscibility affected the biodegradability of PHBV/EVA blends negatively.
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Chikh, Amirouche. "Étude des mélanges PHBV/PBS et des mélanges hybrides PHBV/PBS/sépiolite : préparation, caractérisation physico-mécanique et durabilité." Thesis, Lorient, 2018. http://www.theses.fr/2018LORIS496/document.

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Ce travail de recherche consiste à étudier les relations structure-propriétés de mélanges biopolymères à base de poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) et poly(butylène succinate) (PBS). Il est divisé en trois parties. La première partie est consacrée à l'étude des propriétés des mélanges PHBV/PBS préparés par voie fondue en fonction de la composition en termes de morphologie et de propriétés rhéologiques, mécaniques, thermiques et barrières. Les résultats obtenus ont été discutés par rapport aux polymères de base. La deuxième partie est consacrée à la compatibilisation des mélanges PHBV/PBS et l'amélioration des interactions à l'interface. Les effets de l'incorporation de la sépiolite à 5% en masse et du PHBV greffé par de l’anhydride maléique (PHBV-g-MA) à 5% en masse ont été étudiés en termes de changements morphologiques montrant un effet synergique entre le compatibilisant et la nanocharge sur les l’ensemble des propriétés des mélanges PHBV/PBS. Enfin, une étude sur le recyclage a été menée à travers une évaluation des effets du nombre de cycles d'extrusion sur les propriétés des matériaux. Elle révèle qu'après 6 cycles d'extrusion, la dégradation thermo-mécanique du PHBV est significativement réduite en présence du PBS
The main objective of this work was to study the structure-properties relationships of biopolymerblends based on poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and polybutylene succinate (PBS). The work was devised into three parts. The first part was devoted to the study of the properties of PHBV/PBS blends prepared by melt compounding at different weight ratio in terms of morphology and properties. The results obtained were discussed in terms of properties and compared with the neat polymers. The second part was devoted to the study of compatibility of PHBV/PBS blends aiming to improve the interactions at the interface between the two components. The effects of both sepiolite (5% wt.) and PHBV-g-MA (5% wt.) were studied in terms of properties. The results showed a synergistic effect between the compatibilizer PHBV-g-MA and the nanofiller sepiolite though an increase in thermal, mechanical and rheological properties. The last part dealing with the recyclability of PHBV/PBS through the study of the effects of repeated extrusion cycles on the properties of materials. The results showed that after 6 reprocessing cycles the thermo-mechanical degradation of PHBV is significantly reduced in the presence of PBS
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Benini, Kelly Cristina Coelho de Carvalho [UNESP]. "Compósitos de nanocelulose / PHBV: manta microfibrilica por eletrofiação." Universidade Estadual Paulista (UNESP), 2015. http://hdl.handle.net/11449/123382.

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A produção de nanobiocompósitos tem crescido nos últimos anos considerando a necessidade no desenvolvimento de materiais que visam substituir aqueles produzidos com matéria-prima oriunda do petróleo e que demoram muito tempo para se degradarem, prejudicando o meio ambiente. Dentro deste contexto, foram confeccionados nanobiocompósitos de PHBV/nanocristais de celulose (NCC) por casting e eletrofiação. O desenvolvimento do trabalho consistiu inicialmente na determinação da melhor sequência de tratamentos químicos para a obtenção da celulose a partir do capim-sapê, e as condições determinadas foram: tratamento alcalino com solução de NaOH 5% (m/m), a 75°C, seguido por três etapas de branqueamento com H2O2/NaOH. Em seguida, foi realizado um planejamento de experimentos (PE) com o qual foi possível determinar as melhores condições de hidrólise ácida para a obtenção dos NCC, que foram: H2SO4 60% (m/m), a 60°C por 30 min (NCC4) e H2SO4 64% (m/m), a 35°C por 75 min (NCC9). Posteriormente, outro PE foi realizado para determinar os parâmetros mais adequados para a solubilidade e processamento do PHBV, e os resultados obtidos levaram à escolha dos seguintes parâmetros: solução de PHBV com 5% (m/m) de polímero em solventes dimetilformamida e clorofórmio (razão 22/78) solubilizados a 50°C por 30h, casting a 153°C e eletrofiação com agulha 20x10, rotação do tambor de 27 rpm, distância de trabalho de 10 cm, com condições ambientais próximas a 25°C e 50% de umidade. Por fim, foram confecionados os nanocompósitos PHBV/NCC4 e PHBV/NCC9, com a adição de 1% (m/m) de reforço, pelos processos de casting e eletrofiação, seguindo as condições de solubilidade e processamento estabelecidas no PE. A adição dos NCC nos nanocompósitos obtidos por casting não alterou a transparência dos filmes e proporcionou uma redução ... (Resumo completo, clicar acesso eletrônico abaixo)
The production of nanobiocomposites has grown in recent years considering the need to develop materials to replace those produced using raw materials derived from petroleum and that take a long time to degrade, damaging the environment. However, nanobiocomposites of PHBV/cellulose nanocrystals (CNC), were obtained by solvent casting and electrospinning. First of all, was determined the best sequence of chemical treatments to obtain cellulose from brazilian satintail, and the conditions were: alkali treatment with NaOH solution (5% w/w) at 75°C , followed by three stages of bleaching with H2O2/NaOH. Then, following a design of experiments (DOE) it was possible to determine the best conditions of acid hydrolysis to obtain the CNC: H2SO4 60% (w/w) at 60°C for 30 min (CNC4) and H2SO4 64% (w/w) at 35°C for 75 min (CNC9). Afterwards, other DOE was conducted to determine the most appropriate PHBV solubility and processing parameters, and the results obtained led to the choice of the following parameters: PHBV solution containing 5% (w/w) of polymer in solvent dimethylformamide and chloroform (ratio 22/78), solubilized at 50°C for 30h; casting at 153°C, and electrospinning with needle (20x10), drum rotation of 27 rpm, working distance of 10 cm and environmental conditions close to 25°C and 50% of moisture. Finally, the nanocomposites PHBV/NCC4 and PHBV/NCC9 were obtained with the addition of 1% (w/w) of reinforcement by casting and electrospinning process, following the solubility and processing conditions determined at DOE. The addition of CNC in the nanocomposites obtained by solvent casting did not change the transparency of the films and provided a significant decrease in the polymer crystallization temperature, mainly with the addition of CNC4, whereas for electrospun nanocomposites, provided a considerable improvement in process efficiency, by ... (Complete abstract click electronic access below)
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Benini, Kelly Cristina Coelho de Carvalho. "Compósitos de nanocelulose / PHBV : manta microfibrilica por eletrofiação /." Guaratinguetá, 2015. http://hdl.handle.net/11449/123382.

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Orientador: Herman Jacobus Cornelis Voorwald
Coorientador: Maria Odila Hilário Cioffi
Banca: Mirabel Cerqueira Rezende
Banca: Maysa Furlan
Banca: Marcelo Ornaghi Orlandi
Banca: Heitor Luiz Ornaghi Júnior
Resumo: A produção de nanobiocompósitos tem crescido nos últimos anos considerando a necessidade no desenvolvimento de materiais que visam substituir aqueles produzidos com matéria-prima oriunda do petróleo e que demoram muito tempo para se degradarem, prejudicando o meio ambiente. Dentro deste contexto, foram confeccionados nanobiocompósitos de PHBV/nanocristais de celulose (NCC) por casting e eletrofiação. O desenvolvimento do trabalho consistiu inicialmente na determinação da melhor sequência de tratamentos químicos para a obtenção da celulose a partir do capim-sapê, e as condições determinadas foram: tratamento alcalino com solução de NaOH 5% (m/m), a 75°C, seguido por três etapas de branqueamento com H2O2/NaOH. Em seguida, foi realizado um planejamento de experimentos (PE) com o qual foi possível determinar as melhores condições de hidrólise ácida para a obtenção dos NCC, que foram: H2SO4 60% (m/m), a 60°C por 30 min (NCC4) e H2SO4 64% (m/m), a 35°C por 75 min (NCC9). Posteriormente, outro PE foi realizado para determinar os parâmetros mais adequados para a solubilidade e processamento do PHBV, e os resultados obtidos levaram à escolha dos seguintes parâmetros: solução de PHBV com 5% (m/m) de polímero em solventes dimetilformamida e clorofórmio (razão 22/78) solubilizados a 50°C por 30h, casting a 153°C e eletrofiação com agulha 20x10, rotação do tambor de 27 rpm, distância de trabalho de 10 cm, com condições ambientais próximas a 25°C e 50% de umidade. Por fim, foram confecionados os nanocompósitos PHBV/NCC4 e PHBV/NCC9, com a adição de 1% (m/m) de reforço, pelos processos de casting e eletrofiação, seguindo as condições de solubilidade e processamento estabelecidas no PE. A adição dos NCC nos nanocompósitos obtidos por casting não alterou a transparência dos filmes e proporcionou uma redução ... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The production of nanobiocomposites has grown in recent years considering the need to develop materials to replace those produced using raw materials derived from petroleum and that take a long time to degrade, damaging the environment. However, nanobiocomposites of PHBV/cellulose nanocrystals (CNC), were obtained by solvent casting and electrospinning. First of all, was determined the best sequence of chemical treatments to obtain cellulose from brazilian satintail, and the conditions were: alkali treatment with NaOH solution (5% w/w) at 75°C , followed by three stages of bleaching with H2O2/NaOH. Then, following a design of experiments (DOE) it was possible to determine the best conditions of acid hydrolysis to obtain the CNC: H2SO4 60% (w/w) at 60°C for 30 min (CNC4) and H2SO4 64% (w/w) at 35°C for 75 min (CNC9). Afterwards, other DOE was conducted to determine the most appropriate PHBV solubility and processing parameters, and the results obtained led to the choice of the following parameters: PHBV solution containing 5% (w/w) of polymer in solvent dimethylformamide and chloroform (ratio 22/78), solubilized at 50°C for 30h; casting at 153°C, and electrospinning with needle (20x10), drum rotation of 27 rpm, working distance of 10 cm and environmental conditions close to 25°C and 50% of moisture. Finally, the nanocomposites PHBV/NCC4 and PHBV/NCC9 were obtained with the addition of 1% (w/w) of reinforcement by casting and electrospinning process, following the solubility and processing conditions determined at DOE. The addition of CNC in the nanocomposites obtained by solvent casting did not change the transparency of the films and provided a significant decrease in the polymer crystallization temperature, mainly with the addition of CNC4, whereas for electrospun nanocomposites, provided a considerable improvement in process efficiency, by ... (Complete abstract click electronic access below)
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Leimann, Fernanda Vitória. "Nanopartículas híbridas de polímero natural (PHBV)/polímero sintético." reponame:Repositório Institucional da UFSC, 2012. http://repositorio.ufsc.br/xmlui/handle/123456789/95203.

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Tese (doutorado) - Universidade Federal de Santa Catarina, Centro Tecnológico, Programa de Pós-Graduação em Engenharia Química, Florianópolis, 2011
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O uso de nanopartículas poliméricas como carreadores de fármacos tem sido investigado por aumentar a biodisponibilidade do fármaco e por permitir novas rotas de administração. Polímeros naturais apresentam elevada biodegradabilidade e biocompatibilidade, que são características importantes para estas aplicações biomédicas. No entanto, as propriedades dos polímeros naturais não são tão facilmente manipuláveis como a dos polímeros sintéticos. Neste contexto, nanopartículas blenda (misturas físicas) e híbridas (ligações covalentes entre os polímeros) de polímeros naturais e polímeros sintéticos podem ser uma alternativa interessante para modificação/controle da liberação de fármacos. Neste trabalho, a técnica de miniemulsificação/evaporação do solvente foi utilizada para preparar nanopartículas de PHBV (poli(hidroxibutirato-co-hidroxivalerato)) e nanopartículas blenda PHBV, PS (poliestireno) e P(S-co-MAA) (poli(estireno-co-ácido metacrílico)). O PHBV de massa molar reduzida também foi utilizado para preparar nanopartículas híbridas com PS e P(S-co-MAA) via polimerização em miniemulsão. Os resultados mostraram que o PHBV de baixa massa molar apresentou menor separação de fases em todos os casos, resultando na formação de partículas com morfologia tipo core-shell devido às diferentes tensões interfaciais entre os polímeros e a água. Em relação às nanopartículas híbridas, o aumento da concentração de PHBV levou à redução da taxa de reação e à diminuição da conversão final de monômero, indicando a possibilidade dos radicais de PS em crescimento terem reagido com as duplas ligações terminais formadas durante a redução de massa molar do PHBV. As nanopartículas de PHBV de maior massa molar apresentaram maior degradação por hidrólise. Quando comparadas à degradação de micropartículas de PHBV, as nanopartículas mostraram uma redução da massa molar muito mais rápida devido a sua maior área superficial. Nanopartículas blenda PHBV/PS apresentaram redução da massa molar desprezível após 50 dias de hidrólise, mostrando a possibilidade de modificação da degradação das nanopartículas. Progesterona foi encapsulada nas nanopartículas de PHBV, blenda PHBV/PS e híbridas PHBV/PS e PHBV/P(S-co-MAA). Não houve alteração nas cinéticas de polimerização em miniemulsão em função da adição de progesterona. As maiores eficiências de encapsulação obtidas foram para as nanopartículas de PHBV estabilizadas com lecitina e para as nanopartículas híbridas PHBV/P(Sco-MAA) (95 e 99%, respectivamente).
Nanoparticles composed by natural polymers have been used in controlled release systems due to their biodegradability and biocompatibility. The use of polymer blends or hybrid polymers (presenting covalent bonds between two or more polymers) composed by natural and synthetic polymers is an interesting alternative to modify release rates. In this work the miniemulsification/solvent evaporation technique was used to obtain PHBV (poli(hidroxibutirato-cohidroxivalerato)) nanoparticles as well as PHBV/PS (polystyrene) and PHBV/P(S-co-MAA) (poly(styrene-co-methacrylic acid)) polymer blend nanoparticles. The influence of the preparation method, PHBV molecular weight, surfactant type and concentration, costabilizer type and concentration on the nanoparticles diameter was evaluated. In the case of the blend nanoparticles the evaluated experimental parameters were PS and PHBV molecular weights, and the amount of each polymer. Low molecular weight PHBV showed enhanced compatibility in all cases resulting in the formation of core-shell particles as expected due to the interfacial tensions between the polymers and the water phase. Hybrid nanoparticles composed by PHBV and P(S-co-MAA) or PS were also obtained. The increase in the PHBV amount led to a decrease in the polymerization rates as well in the total monomer conversion suggesting that the growing PS radicals may be reacted with the terminal double bonds of the reduced molecular weight PBHV. The hydrolytic degradation of the PHBV nanoparticles were evaluated for different temperatures, pH and molecular weights showing that the higher the molecular weight the higher the degradation. Nanoparticles degraded faster than PHBV microparticles due to the increased specific surface area. PS/PHBV blend nanoparticles presented negligible molecular weight reduction even after 50 days demonstration that the presence of PF can be used to modify the degradation rates. Progesterone was encapsulated in the PHBV nanoparticles (pure, blend and hybrid polymers). The miniemulsion polymerization kinetics were not affected by the presence of progesterone. The higher encapsulation efficiencies were found in the case of lecithin stabilized pure PHBV nanoparticles as well as in the case of PHBV/P(S-co-MAA) hybrid nanoparticles (95 and 99%, respectively).
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Sultana, Naznin. "Fabrication of PHBV and PHBV-based composite tissue engineering scaffolds through the emulsion freezing/freeze-drying process andevaluation of the scaffolds." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2009. http://hub.hku.hk/bib/B43703665.

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Sultana, Naznin. "Fabrication of PHBV and PHBV-based composite tissue engineering scaffolds through the emulsion freezing/freeze-drying process and evaluation of the scaffolds." Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43703665.

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Zubairi, Saiful Irwan. "Development of biomimetic PHB and PHBV scaffolds for a three dimensional (3-D) in vitro human leukaemia model." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/11131.

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Leukaemia is defined as a group of haematological diseases (related to blood and blood-forming tissue) characterized by malignant proliferation of myeloblasts or lymphoblasts that replace normal bone marrow elements and infiltrate normal tissues. The study of leukaemia has been hindered by the lack of appropriate in vitro models, which can mimic this microenvironment. It is hypothesized that the fabrication of porous 3-D scaffolds for the biomimetic growth of leukaemic cells in vitro could facilitate the study of the disease in its simulated native 3-D niche. In this study, polyhydroxyalkanoate (PHA), in particular poly(hydroxybutyrate) (PHB) and poly(hydroxybutyrate-co-valerate) (PHBV) porous 3-D scaffolds with an improved thickness (in relative to the conventionally made PHA matrices) are utilized and investigated to model the abnormal 3-D leukaemic cellular growth system in the absence of exogenous cytokines. The polymeric porous 3-D scaffolds were fabricated using an ideal polymer concentration of 4% (w/v). The salt-leaching efficacy and the effect of salt residual on the cell growth media were carried out to validate the significant amount of salt remnant inside the porous materials. The physico-chemical characteristics of the porous 3-D scaffolds such as surface wetting, porosity, BET surface area and pore size distribution were studied by means of drop sessile analyzer (DSA), helium gas pycnometry, mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM). To increase probability of cellular attachment and proliferation, the polymeric scaffold surfaces were treated with O2-rf-plasma (100 W at 10 min) and NaOH (0.6M). Next, in order to improve the in vitro 3-D leukaemic cell culture, two main bone marrow extracellular matrix (ECM) proteins which are collagen type I or fibronectin were immobilized via physical adsorption on the treated surfaces of the polymeric porous 3-D scaffolds. Meanwhile, the in vitro degradation studies were conducted on both polymeric scaffolds with the hydrolytic degradation media of phosphate buffered saline (PBS) and cell growth media. The scaffolds were analyzed and compared for mass loss, morphology and pH changed of the PBS and cell growth media throughout 45 weeks and 9 weeks of the study respectively. Overall, PHB and PHBV displayed a good seeding efficiency (24 h) and excellent leukaemic cellular growth for up to 6 weeks (protein-coated scaffolds), assessed by MTS assay and SEM. Once the abnormal hematopoietic 3-D model (cell lines) was established, a new model to culture human primary acute myeloid leukaemia mononuclear cells (AML MNCs) was studied, compared and validated. All leukaemic cells grew better in PHBV scaffolds coated with 62.5 μg/ml collagen type I and sustained cell growth in the absence of exogenous cytokines. As a result, it was concluded that PHBV-collagen scaffolds may provide and could be used, as a practical model with which to study the biology and treatment of primary AML in an in vitro mimicry without the use of 2-D culture system and animal models.
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Vidhate, Shailesh. "Biodegradable Poly(hydroxy Butyrate-co-valerate) Nanocomposites And Blends With Poly(butylene Adipate-co-terephthalate) For Sensor Applications." Thesis, University of North Texas, 2011. https://digital.library.unt.edu/ark:/67531/metadc103405/.

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The utilization of biodegradable polymers is critical for developing “cradle to cradle” mindset with ecological, social and economic consequences. Poly(hydroxy butyrate-co-valerate) (PHBV) shows significant potential for many applications with a polypropylene equivalent mechanical performance. However, it has limitations including high crystallinity, brittleness, small processing window, etc. which need to be overcome before converting them into useful products. Further the development of biodegradable strain sensing polymer sensors for structural health monitoring has been a growing need. In this dissertation I utilize carbon nanotubes as a self sensing dispersed nanofiller. The impact of its addition on PHBV and a blend of PHBV with poly(butylene adipate-co-terephthalate) (PBAT) polymer was examined. Nanocomposites and blends of PHBV, PBAT, and MWCNTs were prepared by melt-blending. The effect of MWCNTs on PHBV crystallinity, crystalline phase, quasi-static and dynamic mechanical property was studied concurrently with piezoresistive response. In PHBV/PBAT blends a rare phenomenon of melting point elevation by the addition of low melting point PBAT was observed. The blends of these two semicrystalline aliphatic and aromatic polyesters were investigated by using differential scanning calorimetry, small angle X-ray scattering, dynamic mechanical analysis, surface energy measurement by contact angle method, polarized optical and scanning electron microscopy, and rheology. The study revealed a transition of immiscible blend compositions to miscible blend compositions across the 0-100 composition range. PHBV10, 20, and 30 were determined to be miscible blends based on a single Tg and rheological properties. The inter-relation between stress, strain, morphological structure and piezoresistive response of MWCNT filled PHBV and PHBV/PBAT blend system was thoroughly investigated. The outcomes of piezoreistivity study indicated MWCNT filled PHBV and PHBV/PBAT blend system as a viable technology for structural health monitoring. Finally, the compostability of pure polymer, blend system, and MWCNT filled system was studied indicating that PBAT and CNT decreased the biodegradability of PHBV with CNT being a better contributor than PBAT.
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Passos, Thayse Marques [UNESP]. "Biodegradação de filmes de Polihidroxibutirato-co-hidroxivalerato (PHBV), polietileno de baixa densidade (PEBD) e blenda de PEBD/PHBV (70/30), com fungos específicos." Universidade Estadual Paulista (UNESP), 2013. http://hdl.handle.net/11449/95033.

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O aumento do consumo de materiais plásticos, no mundo todo, tem sido objeto de grande preocupação e especial atenção por parte da comunidade científica, no sentido de promover o desenvolvimento de materiais que, ao serem descartados sejam biodegradados em tempo mais curto, no meio ambiente. Os plásticos sintéticos mais utilizados atualmente são de difícil degradação, por serem hidrofóbicos e resistentes à ação de enzimas microbianas. Entretanto, o uso de materiais alternativos, tais como as blendas de polímeros biodegradável e sintético, pode minimizar o efeito danoso do descarte desses materiais em lixões e aterros sanitários, por serem suscetíveis à ação de micro-organismo. Este trabalho visou investigar a biodegradação dos filmes de PHBV (biodegradável), PEBD (polietileno de baixa densidade) e da blenda de PEBD/PHBV (70/30), empregando fungos específicos em meios de cultura sólido e líquido, utilizando metodologias como: Microscopia óptica (MO), Microscopia Eletrônica de Varredura (MEV) e Espectroscopia de Absorção no Infravermelho com Transformada de Fourier (FTIR). Os fungos Penicillium funiculosum e Paecilomyces variotii degradam eficientemente o PHBV, sendo que o primeiro degradou o polímero com formação de ácidos insaturados, fortes indicadores da biodegradação deste tipo de material. Além disso, estes fungos aderem significativamente à superfície do PE, mudando expressivamente sua morfologia. A blenda de PE/PHBV (70/30), é um material suscetível à ação destes fungos, tendo sofrido mudanças, inclusive, na sua cristalinidade. Nesta blenda ficou evidente também a ação de proteção do PE, que inibiu o acesso do fungo à fase do PHBV contido na mesma. No meio mineral completo houve consumo da fase amorfa e...
The increase in consumption of plastics in the world has been the subject of great concern and special attention from the scientific community, to promote the development of materials that are biodegradable in a shorter time when discarded in the environment. The most widely used synthetic plastics are hardly degraded, because they are hydrophobic and resistant to the action of microbial enzymes. However, the use of alternative materials, such as blends of biodegradable polymers and synthetic, can minimize the harmful effect of the disposal of these materials in dumps and landfills, because they are susceptible to the action of microorganisms. This work aims to investigate the biodegradation of PHBV films (biodegradable), LDPE (low density polyethylene) and blends of LDPE / PHBV (70/30), using specific fungi in culture media solid and liquid, employing methods such as optical microscopy (OM), scanning electron microscopy (SEM) and Fourier Transform Infrared (FTIR). Penicillium funiculosum and Paecilomyces variotii degrade PHBV efficiently and the first one degraded the polymer producing insaturated acids, strong indicators of the biodegradation of this type of material. Besides that, they adhere significantly on PE surface, changing meaningly the morphology of these materials. The PE / PHBV (70/30) blend, is a material susceptible to the fungi action, having undergone changes, including in its crystallinity. It was also evident the protective action of the PE, preventing the access of the fungus to the PHBV phase contained in the blend. In the complete mineral medium there was a consumption of amorphous and crystalline phases (decrease and increase of carbonyl indices, respectively – FTIR) and in the incomplete mineral medium, the amorphous and crystalline phases were consumed, showing the efficiency of P. funiculosum... (Complete abstract click electronic access below)
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Books on the topic "PHBV"

1

Adam, Sugayo Jawama. Dialog hutan Jawa: Mengurai makna filosofis PHBM. Yogyakarta: Pustaka Pelajar, 2007.

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Markel, A. J. PHEV energy storage and drive cycle impacts. [Golden, Colo.]: National Renewable Energy Laboratory, 2007.

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Schubert, Peter. Molekulare Organisation des PHB-Operons und Charakterisierung des PHB-Synthasegens in Alcaligenes eutrophus. Göttingen: Unitext, 1991.

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Courthiade, Marcel. Romske poslovice: Sar rromano ilo--nanaj p-i sasti phuv. Zagreb?]: Udruga za promicanje obrazovanja Roma u Republici Hrvatskoj "Kali Sara", 2012.

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PHB practical handbook of curve design and generation. Boca Raton: CRC Press, 1994.

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Affianto, Agus. Analisis biaya dan pendapatan dalam pengelolaan PHBM: Sebuah panduan perhitungan bagi-hasil. Bogor, Indonesia: Pustaka Latin, 2005.

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Great Britain. Office of Fair Trading., ed. The regulation of licensed taxi and PHV services in the UK. London: Great Britain, Office of Fair Trading, 2003.

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Perhubungan, Indonesia Departemen. Instruksi Menteri Perhubungan nomor IM.8/UM.206/PHB-91 Tentang Pelaksanaan Hasil Rapat Kerja Tahun 1991. [Jakarta]: Departemen Perhubungan, 1991.

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Hari, Martopo, ed. Perancangan notasi relief (notrel) untuk pendidikan musik tunanetra: Tahap sosialisasi : laporan hasil PHB IX/2 tahun 2002. [Yogyakarta]: Fakultas Seni Pertunjukan, Institut Seni Indonesia Yogyakarta, 2002.

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kelayak lautan kapal Keputusan Menteri Perhubungan no. KM.168/OT.002/Phb.-84 Tentang Organisasi dan Tata Kerja Kantor Lalu Lintas Angkutan Laut, no. KM.169/OT.002/Phb.-84 Tentang Organisasi dan Tata Kerja Kantor Pelabuhan, no. KM.170/OT.002/Phb.-84 Tentang Organisasi dan Tata Kerja Kantor Administrator Pelabuhan: Organisasi dan tata kerja kantor lalulintas angkutan laut. [Jakarta: s.n., 1987.

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Book chapters on the topic "PHBV"

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Şendil, Dilek, İhsan Gürsel, Donald L. Wise, and Vasıf Hasırcı. "Antibiotic Release from Biodegradable PHBV Microparticles." In Biomedical Science and Technology, 89–96. Boston, MA: Springer US, 1998. http://dx.doi.org/10.1007/978-1-4615-5349-6_9.

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Sultana, Naznin. "Biodegradable PHBV Polymer-Based Scaffolds for Bone Tissue Engineering." In Biodegradable Polymer-Based Scaffolds for Bone Tissue Engineering, 43–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-34802-0_3.

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Javadi, Alireza, Srikanth Pilla, Shaoqin Gong, and Lih-Sheng Turng. "Biobased and Biodegradable PHBV-Based Polymer Blends and Biocomposites: Properties and Applications." In Handbook of Bioplastics and Biocomposites Engineering Applications, 372–96. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2011. http://dx.doi.org/10.1002/9781118203699.ch14.

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Duan, Bin, and Min Wang. "Immobilization of Heparin on Gelatin Modified Three-Dimensional Osteoconductive Ca-P/PHBV Nanocomposite Scaffolds." In Ceramic Transactions Series, 43–51. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2012. http://dx.doi.org/10.1002/9780470909898.ch5.

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Tong, Ho Wang, and Min Wang. "Effects of Processing Parameters on the Morphology and Size of Electrospun PHBV Micro- and Nano-Fibers." In Advances in Composite Materials and Structures, 1233–36. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-427-8.1233.

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Duan, Bin, William W. Lu, and Min Wang. "Selective Laser Sintered Ca-P/PHBV Nanocomposite Scaffolds with Sustained Release of rhBMP-2 for Bone Tissue Engineering." In Advances in Bioceramics and Porous Ceramics IV, 37–48. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2011. http://dx.doi.org/10.1002/9781118095263.ch5.

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Yaacob, Noorulnajwa Diyana, Hanafi Ismail, and Sam Sung Ting. "Tensile, Thermal Properties, and Biodegradability Test of Paddy Straw Powder-Filled Polyhydroxybutyrate-3-Valerate (PHBV) Biocomposites: Acrylation Pretreatment." In Recycled Polymer Blends and Composites, 307–22. Cham: Springer International Publishing, 2023. http://dx.doi.org/10.1007/978-3-031-37046-5_15.

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Panda, Pradeep Kumar, and Pranjyan Dash. "Preparation, Characterization, and Evaluation of Antibacterial Properties of Poly(3-Hydroxybutarate-Co-3-Hydroxyvalerate) (PHBV)-Based Films and Coatings." In Biopolymer-Based Films and Coatings, 291–308. Boca Raton: CRC Press, 2023. http://dx.doi.org/10.1201/9781003303671-13.

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Turner, A., S. Zainuddin, D. Kodali, and S. Jeelani. "Characterization of Multi-walled Carbon Nanotube Reinforced into Poly(3-Hydroxybutyrate-Co-3-Hydroxyvalerate) (PHBV)-Epoxidized Natural Rubber 50 (ENR50) Biofilms." In The Minerals, Metals & Materials Series, 736–47. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-92381-5_70.

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Bährle-Rapp, Marina. "PHB-Ester." In Springer Lexikon Kosmetik und Körperpflege, 423. Berlin, Heidelberg: Springer Berlin Heidelberg, 2007. http://dx.doi.org/10.1007/978-3-540-71095-0_7886.

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Conference papers on the topic "PHBV"

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Zhao, Haibin, and Xiangfang Peng. "The Effect of Nanoclay on the Rheological Properties of Polylactic Acid/Polyhydroxybutyrate-Valerate Blends." In ASME 2015 International Manufacturing Science and Engineering Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/msec2015-9223.

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In this article, the effects of nanoclay (CN) on the rheological behavior of polylactic acid (PLA)/polyhydroxybutyrate–valerate (PHBV) blends was investigated. The rheological behavior of PLA/PHBV blends showed a Newtonian plateau that converted to strong shear thinning behavior over the full range of frequency by the incorporation of nanoclay. The results indicate that the storage modulus and complex viscosity of PLA/PHBV blends were sensitive to nanofillers. An obvious pseudo-solid-like behavior over a wide range of frequency in PLA/PHBV/CN nanocomposites showed that the strong interaction between the PLA/PHBV blend and the nanoclay restricted the relaxation process of the polymer chains. Therefore, the PLA/PHBV/CN nanocomposites possess a higher modulus and greater melt strength, which are desirable for creating an improved foamed structure when manufactured via microcellular injection molding.
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Hossain, Mohammad K., Samira N. Shaily, Hadiya J. Harrigan, and Terrie Mickens. "Fabrication and Characterization of Bio-Based Poly Lactic Acid/Polyhydroxybutyrate-Valerate (PLA/PHBV) Blend With Nanoclay." In ASME 2016 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/imece2016-67813.

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The objective of this research is to prepare a hybrid biopolymer blend using PLA and PHBV with enhanced mechanical and thermal properties. Bio-based PLA and PHBV blends were prepared using the melt-mixing procedure. Tensile, FTIR, DSC, TGA, optical microscopy (OM), and scanning electron microscopy (SEM) tests were performed to investigate mechanical properties, bonding interaction, glass transition temperature, melting and crystalline enthalpy, thermal decomposition, and morphological analysis. Different percent (1, 2, and 3 wt%) of nanoclay was added to the system to observe the bonding interaction. It was observed that the crystallinity increases with increasing amount of nanoclay. The result showed that the tensile strength of PLA thin film and PHBV film was found to be 31.1 MPa and 14.41 MPa, respectively. Hence, PLA has better mechanical property than PHBV. On the other hand, thermal property of PHBV thin film was found to be better than that of PLA. To optimize both mechanical and thermal properties of PLA and PHBV hybrid biopolymer blend, using various combinations of PLA/PHBV including 25/75, 50/50 and 75/25 wt% a hybrid biopolymer blend was prepared. Among them, PLA-PHBV (75/25 wt%) with 2 wt% nanoclay resulted in the best outcome. The tensile strength of this prepared polymer blend was 29.34 MPa. Thermal analysis demonstrated two melting temperatures: 238.37 °C and 308.31 °C, respectively. Two glass transition temperatures were found from thermal tests which are the indication of the solution immiscibility. It had also been observed that the adding of nanoclay enhances tensile properties as well as thermal stability up to 2 wt%. It is revealed from the optical and SEM micrographs that the 2 wt% NC was dispersed uniformly throughout the resin blend.
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Ponjavic, Marijana, Ivana Malagurski, Ana Salevic-Jelic, Jelena Lazic, and Jasmina Nikodinovic-Runic. "UV-blocking sustainable food packaging based on polyhydroxyalkanoate and bacterial pigment prodigiosin." In 2nd International Conference on Chemo and Bioinformatics. Institute for Information Technologies, University of Kragujevac, 2023. http://dx.doi.org/10.46793/iccbi23.351p.

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New film materials based on bacterial biomolecules polyhydroxyalkanoate (poly(3-hydroxybutyrate-co-3-hydroxyvalerate) PHBV) and prodigiosin (PG) were produced by solvent casting as a potential food packaging material. Film precursors were obtained in a sustainable manner via microbial fermentation using waste stream-based substrates (cooking oil and second-grade canned meat, after the expiry date). The incorporation of PG into the PHBV has influenced the morphology and functionality of the obtained materials. PG acted as a nucleating agent, affecting in turn PHBV/PG film surface morphology. The films were intensively colored, transparent and blocked UV-light. An increase in PG content decreased film transparency but it did not affect UV-blocking ability. Migration experiments have shown that films possess the potential to release PG into lipophilic food simulant media where it has exhibited antioxidative action. The obtained results suggest that PHBV/PG films can be potentially used as sustainable and active food packaging materials.
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Gallot-Lavallee, O., and L. Heux. "Dielectric spectroscopy on a PHBV bio-polymer." In 2013 IEEE Conference on Electrical Insulation and Dielectric Phenomena - (CEIDP 2013). IEEE, 2013. http://dx.doi.org/10.1109/ceidp.2013.6748275.

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Resch, J., M. Kreutzbruck, and C. Bonten. "Modification of PHBV-blends with a biodegradable plasticizer." In FRACTURE AND DAMAGE MECHANICS: Theory, Simulation and Experiment. AIP Publishing, 2020. http://dx.doi.org/10.1063/5.0028771.

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Ciuprina, Florin, Laura Andrei, Sergiu Stoian, Raluca Gabor, and Denis Panaitescu. "Dielectric Response and Dynamic Mechanical Analysis of PHBV-TiO2 Nanocomposites." In 2020 IEEE 3rd International Conference on Dielectrics (ICD). IEEE, 2020. http://dx.doi.org/10.1109/icd46958.2020.9341988.

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Javadi, Alireza, Srikanth Pilla, Shaoqin Gong, Yottha Srithep, Jungjoo Lee, and Lih-Sheng Turng. "Processing and Characterization of Solid and Microcellular PHBV/Coir Fiber Composites." In SAE 2010 World Congress & Exhibition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2010. http://dx.doi.org/10.4271/2010-01-0422.

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Chen, Haifeng, and Lingmei Guo. "Preparation of ZnS Modified PHBV Film by Chemical Bath Deposition Method." In International Conference on Chemical,Material and Food Engineering. Paris, France: Atlantis Press, 2015. http://dx.doi.org/10.2991/cmfe-15.2015.1.

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Yuping Zhang, Yanyan Wang, Lanxin Lv, Shancheng Yan, Haitao Wang, Yong Zhang, Dan Zhu, Ningping Huang, and Zhongdang Xiao. "Cell affinity of PHBV thin films evaluated by a parallel plate flow chamber." In 2009 4th IEEE International Conference on Nano/Micro Engineered and Molecular Systems. IEEE, 2009. http://dx.doi.org/10.1109/nems.2009.5068665.

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Kuntanoo, K., S. Promkotra, and P. Kaewkannetra. "Physical-biopolymer characterization of polyhydroxybutyrate-co-hydroxyvalerate (PHBV) blended with natural rubber latex." In 4TH INTERNATIONAL CONGRESS IN ADVANCES IN APPLIED PHYSICS AND MATERIALS SCIENCE (APMAS 2014). AIP Publishing LLC, 2015. http://dx.doi.org/10.1063/1.4914254.

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Reports on the topic "PHBV"

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Duoba, Michael. Performance Validation of Advanced PHEV Vehicle. Office of Scientific and Technical Information (OSTI), December 2016. http://dx.doi.org/10.2172/1493414.

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Duoba, Michael. Performance Validation of Advanced PHEV Vehicle. Office of Scientific and Technical Information (OSTI), December 2016. http://dx.doi.org/10.2172/1493417.

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Weber, Adrienne M., and Karen R. Sikes. PHEV Market Introduction Workshop Summary Report. Office of Scientific and Technical Information (OSTI), March 2009. http://dx.doi.org/10.2172/993772.

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Bazzi, Abdullah, and Steven Barnhart. Advancing Transportation through Vehicle Electrification - PHEV. Office of Scientific and Technical Information (OSTI), December 2014. http://dx.doi.org/10.2172/1182581.

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Heinanen, J., F. Baker, W. Weiss, and J. Wroclawski. Assured Forwarding PHB Group. RFC Editor, June 1999. http://dx.doi.org/10.17487/rfc2597.

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Jacobson, V., K. Nichols, and K. Poduri. An Expedited Forwarding PHB. RFC Editor, June 1999. http://dx.doi.org/10.17487/rfc2598.

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Rugh, J. Impact of Sungate EP on PHEV Performance: Results of a Simulated Solar Reflective Glass PHEV Dynamometer Test. Office of Scientific and Technical Information (OSTI), June 2009. http://dx.doi.org/10.2172/957994.

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Abas Goodarzi. Bi-Directional DC-DC Converter for PHEV Applications. Office of Scientific and Technical Information (OSTI), January 2011. http://dx.doi.org/10.2172/1035860.

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Li, Yan, Yuhao Luo, and Xin Lu. PHEV Energy Management Optimization Based on Multi-Island Genetic Algorithm. SAE International, March 2022. http://dx.doi.org/10.4271/2022-01-0739.

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The plug-in hybrid electric vehicle (PHEV) gradually moves into the mainstream market with its excellent power and energy consumption control, and has become the research target of many researchers. The energy management strategy of plug-in hybrid vehicles is more complicated than conventional gasoline vehicles. Therefore, there are still many problems to be solved in terms of power source distribution and energy saving and emission reduction. This research proposes a new solution and realizes it through simulation optimization, which improves the energy consumption and emission problems of PHEV to a certain extent. First, on the basis that MATLAB software has completed the modeling of the key components of the vehicle, the fuzzy controller of the vehicle is established considering the principle of the joint control of the engine and the electric motor. Afterwards, based on the Isight and ADVISOR co-simulation platform, with the goal of ensuring certain dynamic performance and optimal fuel economy of the vehicle, the multi-island genetic algorithm is used to optimize the parameters of the membership function of the fuzzy control strategy to overcome it to a certain extent. The disadvantages of selecting parameters based on experience are compensated for, and the efficiency and feasibility of fuzzy control are improved. Finally, the PHEV vehicle model simulation comparison was carried out under the UDDS working condition through ADVISOR software. The optimization results show that while ensuring the required power performance, the vehicle fuzzy controller after parameter optimization using the multi-island genetic algorithm is more efficient, which can significantly reduce vehicle fuel consumption and improve exhaust emissions.
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Davie, B., A. Charny, J. C. R. Bennet, K. Benson, J. Y. Le, W. Courtney, S. Davari, V. Firoiu, and D. Stiliadis. An Expedited Forwarding PHB (Per-Hop Behavior). RFC Editor, March 2002. http://dx.doi.org/10.17487/rfc3246.

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