Journal articles: 'Commodity polymer'

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OCHI, Takashi. "Nanofibers of Commodity Polymer." Kobunshi 55, no. 3 (2006): 151. http://dx.doi.org/10.1295/kobunshi.55.151.

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Tomita, K. "Microbial Degradability of Commodity Synthetic Polymer." Sen'i Kikai Gakkaishi (Journal of the Textile Machinery Society of Japan) 46, no. 10 (1993): P379—P383. http://dx.doi.org/10.4188/transjtmsj.46.10_p379.

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Jehanno, Coralie, Jeremy Demarteau, Daniele Mantione, Maria C. Arno, Fernando Ruipérez, James L. Hedrick, Andrew P. Dove, and Haritz Sardon. "Synthesis of Functionalized Cyclic Carbonates through Commodity Polymer Upcycling." ACS Macro Letters 9, no. 4 (March 11, 2020): 443–47. http://dx.doi.org/10.1021/acsmacrolett.0c00164.

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Verpaalen, Rob C. P., Tom Engels, Albert P. H. J. Schenning, and Michael G. Debije. "Stimuli-Responsive Shape Changing Commodity Polymer Composites and Bilayers." ACS Applied Materials & Interfaces 12, no. 35 (August 6, 2020): 38829–44. http://dx.doi.org/10.1021/acsami.0c10802.

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Abdullahi, Wasiu, Martin Crossman, and Peter Charles Griffiths. "Surfactant-Modulation of the Cationic-Polymer-Induced Aggregation of Anionic Particulate Dispersions." Polymers 12, no. 2 (February 1, 2020): 287. http://dx.doi.org/10.3390/polym12020287.

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Commodity formulations contain many chemically distinct components and their mutual interactions define the beneficial characteristics of the formulation. Mixing oppositely charged polymers and surfactants invariably induces macroscopic phase separation, to a degree dependent on the prevailing polymer and surface charge densities, and the interaction can be modulated by added ionic surfactants. Here, it is shown that a general universality exists between the charge present on a series of cationic-modified cellulose polymers—the charge being controlled either by the degree of cationic modification of the polymer itself or through the subsequent level of anionic surfactant binding—and its capacity to remove anionic colloidal material from solution, be that silica particles or polystyrene-butadiene lattices. Particulate material not removed from solution bears no adsorbed polymer, i.e., the particle surface is bare. Addition of nonionic surfactant does not negate this universality, implying that the nonionic surfactant is largely a spectator molecule or structure (micelle) in these systems, and that the dominant force is an electrostatic one.

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Lorandi, Francesca, Tong Liu, Sajjad Dadashi-Silab, Yuqi Zhao, Rongguan Yin, Jay Whitacre, and Krzysztof Matyjaszewski. "Self-Healing Commodity Polymer Electrolytes for Reliable Li Metal Batteries." ECS Meeting Abstracts MA2021-01, no. 6 (May 30, 2021): 383. http://dx.doi.org/10.1149/ma2021-016383mtgabs.

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Trott, G., P. K. Saini, and C. K. Williams. "Catalysts for CO 2 /epoxide ring-opening copolymerization." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 374, no. 2061 (February 28, 2016): 20150085. http://dx.doi.org/10.1098/rsta.2015.0085.

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This article summarizes and reviews recent progress in the development of catalysts for the ring-opening copolymerization of carbon dioxide and epoxides. The copolymerization is an interesting method to add value to carbon dioxide, including from waste sources, and to reduce pollution associated with commodity polymer manufacture. The selection of the catalyst is of critical importance to control the composition, properties and applications of the resultant polymers. This review highlights and exemplifies some key recent findings and hypotheses, in particular using examples drawn from our own research.

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Kim, Jung Woo, Seung Hwa Yoo, Young Bae Kong, Sung Oh Cho, and Eun Je Lee. "Hydrophilicity Improvement of Polymer Surfaces Induced by Simultaneous Nuclear Transmutation and Oxidation Effects Using High-Energy and Low-Fluence Helium Ion Beam Irradiation." Polymers 12, no. 12 (November 24, 2020): 2770. http://dx.doi.org/10.3390/polym12122770.

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Two commodity polymers, polystyrene (PS) and high-density polyethylene (HDPE), were irradiated by high-energy He ion beams at low fluence to examine the wettability changes at different fluences. The water contact angles of the PS and HDPE surfaces were reduced from 78.3° to 46.7° and 81.5° to 58.5°, respectively, upon increasing the fluence from 0 to 1 × 1013 He2+/cm2 for irradiation durations ≤4 min. Surface analyses were performed to investigate these wettability changes. Surface texture evaluations via scanning electron and atomic force microscopies indicated non-remarkable changes by irradiation. However, the chemical structures of the irradiated polymer surfaces were notable. The high-energy He ions induced nuclear transmutation of C to N, leading to C–N bond formation in the polymer chains. Further, C–O and C=O bonds were formed during irradiation in air because of polymer oxidation. Finally, amide and ester groups were generated by irradiation. These polar groups improved hydrophilicity by increasing surface energies. Experiments with other polymers can further elucidate the correlation between polymer structure and surface wettability changes due to high-energy low-fluence He ion irradiation. This method can realize simple and effective utilization of commercial cyclotrons to tailor polymer surfaces without compromising surface texture and mechanical integrity.

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Tseghai, Granch Berhe, Desalegn Alemu Mengistie, Benny Malengier, Kinde Anlay Fante, and Lieva Van Langenhove. "PEDOT:PSS-Based Conductive Textiles and Their Applications." Sensors 20, no. 7 (March 28, 2020): 1881. http://dx.doi.org/10.3390/s20071881.

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The conductive polymer complex poly (3,4-ethylene dioxythiophene):polystyrene sulfonate (PEDOT:PSS) is the most explored conductive polymer for conductive textiles applications. Since PEDOT:PSS is readily available in water dispersion form, it is convenient for roll-to-roll processing which is compatible with the current textile processing applications. In this work, we have made a comprehensive review on the PEDOT:PSS-based conductive textiles, methods of application onto textiles and their applications. The conductivity of PEDOT:PSS can be enhanced by several orders of magnitude using processing agents. However, neat PEDOT:PSS lacks flexibility and strechability for wearable electronics applications. One way to improve the mechanical flexibility of conductive polymers is making a composite with commodity polymers such as polyurethane which have high flexibility and stretchability. The conductive polymer composites also increase attachment of the conductive polymer to the textile, thereby increasing durability to washing and mechanical actions. Pure PEDOT:PSS conductive fibers have been produced by solution spinning or electrospinning methods. Application of PEDOT:PSS can be carried out by polymerization of the monomer on the fabric, coating/dyeing and printing methods. PEDOT:PSS-based conductive textiles have been used for the development of sensors, actuators, antenna, interconnections, energy harvesting, and storage devices. In this review, the application methods of PEDOT:SS-based conductive polymers in/on to a textile substrate structure and their application thereof are discussed.

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Wang, Zongtao, Yu Gu, Mingyu Ma, and Mao Chen. "Strong, Reconfigurable, and Recyclable Thermosets Cross-Linked by Polymer–Polymer Dynamic Interaction Based on Commodity Thermoplastics." Macromolecules 53, no. 3 (January 21, 2020): 956–64. http://dx.doi.org/10.1021/acs.macromol.9b02325.

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Mackley, Malcolm. "The Scientific and Technological Route to the Manufacture of High-Modulus Polyethylene." MRS Bulletin 22, no. 9 (September 1997): 47–50. http://dx.doi.org/10.1557/s088376940003400x.

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Polyethylene has been manufactured commercially for over sixty years. However recently a high-modulus variant has become available. This article describes the background to the development of high-modulus polyethylene and describes the story behind the sequence of scientific discoveries and technological developments that occurred to enable this advance.Polyethylene was discovered by accident in the 1930s when two scientists working for the ICI chemical company carried out a series of experiments to study the effect of pressure on the reaction kinetics of certain organic liquids and gases. During these experiments, the scientists noted a waxy deposit in their small reaction vessel which marked the birth of one of the world's largest commodity polymers. The crystallographic structure of polyethylene was determined by another ICI industrial scientist who at the time was pioneering x-ray techniques. The crystallography of polyethylene, shown in Figure 1, is relatively simple in that it shows the long CH2-CH2 polymer chains packed in the all “trans” configuration to form an orthorhombic cell.Polyethylene rapidly developed as a commodity thermoplastic finding application in injection molding, extrusion, and packaging. Its prime material characteristics are its toughness, flexibility, and ease of processing. The stiffness of the polymer for most applications was found to be of the order of 1 GPa, which was similar to other thermoplastics but less than metals such as aluminum at 60 GPa and steel at 210 GPa.

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Martín, Jaime, Dong Zhao, Thomas Lenz, Ilias Katsouras, Dago M. de Leeuw, and Natalie Stingelin. "Solid-state-processing of δ-PVDF." Materials Horizons 4, no. 3 (2017): 408–14. http://dx.doi.org/10.1039/c7mh00007c.

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Solid-state pressing is used to produce, in one single-step and without the need to mechanically stretch thin foils, ferroelectric structures from the commodity polymer poly(vinylidene fluoride) (PVDF) with comparable piezoelectric properties to biaxially stretched β-PVDF.

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Hattori, H., Y. Ide, and T. Sano. "Microporous titanate nanofibers for highly efficient UV-protective transparent coating." J. Mater. Chem. A 2, no. 39 (2014): 16381–88. http://dx.doi.org/10.1039/c4ta02975e.

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Interzeolite conversion was applied to convert a layered titanate into a microporous titanate nanofiber, which hardly showed photocatalytic activity and exhibited extremely low refractive index and then could be used as a UV absorber embedded in commodity organic polymer coatings.

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Sahu, Pranabesh, Anil K. Bhowmick, and Gergely Kali. "Terpene Based Elastomers: Synthesis, Properties, and Applications." Processes 8, no. 5 (May 8, 2020): 553. http://dx.doi.org/10.3390/pr8050553.

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The limited source of fossil-fuel and the predominance of petroleum-based chemistry in the manufacturing of commodity polymers has generated tremendous interest in replacing the fossil source-based polymers with renewable counterparts. The field of sustainable elastomers has grown in the past three decades, from a few examples to a plethora of reports in modern polymer science and technology. Applications of elastomers are huge and vital for everyday living. The present review aims to portray a birds-eye view of various sustainable elastomers obtained from the wide family of acyclic terpenes (renewable feedstocks from different plant oils) via various polymerization techniques and their properties, as well as plausible developments in the future applications of sustainable polymers. Not only the homopolymers, but also their copolymers with both green and commercial fossil based comonomers, are reviewed.

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Bhattacharyya, Debes, R. J. Shields, and S. Fakirov. "Characterisation and Novel Applications of Fibrillar Polymer Composites." Advanced Materials Research 47-50 (June 2008): 1278–81. http://dx.doi.org/10.4028/www.scientific.net/amr.47-50.1278.

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Polymer-reinforced polymer composites have been successfully created from blends of engineering and commodity plastics. These microfibril reinforced composites (MFCs) contain molecularly oriented in-situ fibrils, evenly dispersed throughout a homogeneous matrix. MFCs have several potential applications in a range of areas including food packaging materials and biomedical scaffolds. This paper provides an overview of the characterisation of several MFCs derived from polyethylene/poly(ethylene terephthalate) (PE/PET) blends. It investigates the tensile properties of MFCs with different microfibril orientations as a result of various consolidation techniques. It also describes a study on the oxygen permeability of moulded MFC films and evidence of biological cell growth on microfibrillar polymer structures.

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Barrera, Cindy S., and Katrina Cornish. "Characterization of Agricultural and Food Processing Residues for Potential Rubber Filler Applications." Journal of Composites Science 3, no. 4 (November 26, 2019): 102. http://dx.doi.org/10.3390/jcs3040102.

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Large volumes of agricultural and food processing residues are generated daily around the world. Despite the various potential uses reported for this biomass, most are still treated as waste that requires disposal and negatively impacts the environmental footprint of the primary production process. Increasing attention has been paid toward the use of these residues as alternative fillers for rubber and other large-scale commodity polymers to reduce dependence on petroleum. Nevertheless, characterization of these alternative fillers is required to define compatibility with the specific polymer, identify filler limitations, understand the properties of the resulting composites, and modify the materials to enable the engineering of composites to exploit all the potential advantages of these residue-derived fillers.

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Vora, Nemi, Peter R. Christensen, Jérémy Demarteau, Nawa Raj Baral, Jay D. Keasling, Brett A. Helms, and Corinne D. Scown. "Leveling the cost and carbon footprint of circular polymers that are chemically recycled to monomer." Science Advances 7, no. 15 (April 2021): eabf0187. http://dx.doi.org/10.1126/sciadv.abf0187.

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Mechanical recycling of polymers downgrades them such that they are unusable after a few cycles. Alternatively, chemical recycling to monomer offers a means to recover the embodied chemical feedstocks for remanufacturing. However, only a limited number of commodity polymers may be chemically recycled, and the processes remain resource intensive. We use systems analysis to quantify the costs and life-cycle carbon footprints of virgin and chemically recycled polydiketoenamines (PDKs), next-generation polymers that depolymerize under ambient conditions in strong acid. The cost of producing virgin PDK resin using unoptimized processes is ~30-fold higher than recycling them, and the cost of recycled PDK resin ($1.5 kg−1) is on par with PET and HDPE, and below that of polyurethanes. Virgin resin production is carbon intensive (86 kg CO2e kg−1), while chemical recycling emits only 2 kg CO2e kg−1. This cost and emissions disparity provides a strong incentive to recover and recycle future polymer waste.

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Mader, Markus, Oliver Schlatter, Barbara Heck, Andreas Warmbold, Alex Dorn, Hans Zappe, Patrick Risch, Dorothea Helmer, Frederik Kotz, and Bastian E. Rapp. "High-throughput injection molding of transparent fused silica glass." Science 372, no. 6538 (April 8, 2021): 182–86. http://dx.doi.org/10.1126/science.abf1537.

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Glass is one of the most relevant high-performance materials that has the benefit of a favorable environmental footprint compared with that of other commodity materials. Despite the advantageous properties of glasses, polymers are often favored because they can be processed using scalable industrial replication techniques like injection molding (IM). Glasses are generally processed through melting, which is both energy intensive and technologically challenging. We present a process for glassworks using high-throughput IM of an amorphous silicon dioxide nanocomposite that combines established process technologies and low-energy sintering. We produce highly transparent glass using classical IM and sintering, allowing for a potentially substantial reduction in energy consumption. Our strategy merges polymer and glass processing, with substantial implications for glass utilization.

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Al-Samhan, Meshal, Fatema Al-Attar, Jamal Al-Fadhli, and Mustafa Al-Shamali. "The Influence of Nano CaCO3 on Nucleation and Interface of PP Nano Composite: Matrix Processability and Impact Resistance." Polymers 13, no. 9 (April 25, 2021): 1389. http://dx.doi.org/10.3390/polym13091389.

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Polypropylene (PP) is a commodity material that has been increasingly used in different industries in the past two decades due to its versatile properties when enhanced with additives. Homo polypropylene, in general, has weak mechanical properties and limited chemical resistance; thus, using a different type of fillers to adjust such properties to fit the required applications opened a large market for this commodity. Understanding the interface constituent between the polymer matrix and the added filler and the nucleation behavior is a key to fine control of the enhancement of PP properties. In this study, PP was incorporated with nano calcium carbonate (CaCO3) at 2 and 5 wt% in the presence of maleic anhydride (MAH) to overcome the weak interface due to low polymer polarity. The mix was compounded in a twin screws extruder at a temperature range of 180–200 °C ; then, the prepared samples were left to dry for 24 h at 25 °C. Nuclear Magnetic Resonance (NMR) was used to study the interface adhesion of the nanofiller and the curved revealed that at 2% of nano CaCO3 PP structure remained the same and the nano experienced good adhesion to the polymer matrix. The mechanical impact resistance results showed a real enhancement to the polymer matrix of the nanocomposite by 37%. Moreover, DSC results showed a faster crystallinity rate due to the nanofiller acting as a nucleating agent and rheology tests indicated that low content of nano additive (2%) has better processability behavior, with suitable viscosity complex values at high frequencies.

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Tawiah, Benjamin, Bin Yu, and Bin Fei. "Advances in Flame Retardant Poly(Lactic Acid)." Polymers 10, no. 8 (August 6, 2018): 876. http://dx.doi.org/10.3390/polym10080876.

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PLA has become a commodity polymer with wide applications in a number of fields. However, its high flammability with the tendency to flow in fire has limited its viability as a perfect replacement for the petrochemically-engineered plastics. Traditional flame retardants, which may be incorporated into PLA without severely degrading the mechanical properties, are the organo-halogen compounds. Meanwhile, these compounds tend to bioaccumulate and pose a risk to flora and fauna due to their restricted use. Research into PLA flame retardants has largely focused on organic and inorganic compounds for the past few years. Meanwhile, the renewed interest in the development of environmentally sustainable flame retardants (FRs) for PLA has increased significantly in a bid to maintain the integrity of the polymer. A review on the development of new flame retardants for PLA is presented herein. The focus is on metal oxides, phosphorus-based systems, 2D and 1D nanomaterials, hyperbranched polymers, and their combinations, which have been applied for flame retarding PLA are discussed. The paper also reviews briefly the correlation between FR loadings and efficiency for various FR systems, and their effects on processing and mechanical properties.

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Wang, Yun-Yan, Xianzhi Meng, Yunqiao Pu, and Arthur J. Ragauskas. "Recent Advances in the Application of Functionalized Lignin in Value-Added Polymeric Materials." Polymers 12, no. 10 (October 3, 2020): 2277. http://dx.doi.org/10.3390/polym12102277.

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The quest for converting lignin into high-value products has been continuously pursued in the past few decades. In its native form, lignin is a group of heterogeneous polymers comprised of phenylpropanoids. The major commercial lignin streams, including Kraft lignin, lignosulfonates, soda lignin and organosolv lignin, are produced from industrial processes including the paper and pulping industry and emerging lignocellulosic biorefineries. Although lignin has been viewed as a low-cost and renewable feedstock to replace petroleum-based materials, its utilization in polymeric materials has been suppressed due to the low reactivity and inherent physicochemical properties of lignin. Hence, various lignin modification strategies have been developed to overcome these problems. Herein, we review recent progress made in the utilization of functionalized lignins in commodity polymers including thermoset resins, blends/composites, grafted functionalized copolymers and carbon fiber precursors. In the synthesis of thermoset resins such as polyurethane, phenol-formaldehyde and epoxy, they are covalently incorporated into the polymer matrix, and the discussion is focused on chemical modifications improving the reactivity of technical lignins. In blends/composites, functionalization of technical lignins is based upon tuning the intermolecular forces between polymer components. In addition, grafted functional polymers have expanded the utilization of lignin-based copolymers to biomedical materials and value-added additives. Different modification approaches have also been applied to facilitate the application of lignin as carbon fiber precursors, heavy metal adsorbents and nanoparticles. These emerging fields will create new opportunities in cost-effectively integrating the lignin valorization into lignocellulosic biorefineries.

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Liao, Xiaojian, Martin Dulle, Juliana Martins de Souza e Silva, Ralf B. Wehrspohn, Seema Agarwal, Stephan Förster, Haoqing Hou, Paul Smith, and Andreas Greiner. "High strength in combination with high toughness in robust and sustainable polymeric materials." Science 366, no. 6471 (December 12, 2019): 1376–79. http://dx.doi.org/10.1126/science.aay9033.

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In materials science, there is an intrinsic conflict between high strength and high toughness, which can be resolved for different materials only through the use of innovative design principles. Advanced materials must be highly resistant to both deformation and fracture. We overcome this conflict in man-made polymer fibers and show multifibrillar polyacrylonitrile yarn with a toughness of 137 ± 21 joules per gram in combination with a tensile strength of 1236 ± 40 megapascals. The nearly perfect uniaxial orientation of the fibrils, annealing under tension in the presence of linking molecules, is essential for the yarn’s notable mechanical properties. This underlying principle can be used to create similar strong and tough fibers from other commodity polymers in the future and can be used in a variety of applications in areas such as biomedicine, satellite technology, textiles, aircrafts, and automobiles.

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Kuřitka, Ivo, Vladimír Sedlařík, Diana Harea, Evghenii Harea, Pavel Urbánek, Ivana Šloufová, Radek Coufal, and Jiří Zedník. "Polymer Labelling with a Conjugated Polymer-Based Luminescence Probe for Recycling in the Circular Economy." Polymers 12, no. 6 (May 28, 2020): 1226. http://dx.doi.org/10.3390/polym12061226.

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In this paper, we present the use of a disubstituted polyacetylene with high thermal stability and quantum yield as a fluorescence label for the identification, tracing, recycling, and eventually anti-counterfeiting applications of thermoplastics. A new method was developed for the dispersion of poly[1-phenyl-2-[p-(trimethylsilyl)phenyl]acetylene] (PTMSDPA) into polymer blends. For such purposes, four representative commodity plastics were selected, i.e., polypropylene, low-density polyethylene, poly(methyl methacrylate), and polylactide. Polymer recycling was mimicked by two reprocessing cycles of the material, which imparted intensive luminescence to the labelled polymer blends when excited by proper illumination. The concentration of the labelling polymer in the matrices was approximately a few tens ppm by weight. Luminescence was visible to the naked eye and survived the simulated recycling successfully. In addition, luminescence emission maxima were correlated with polymer polarity and glass transition temperature, showing a marked blueshift in luminescence emission maxima with the increase in processing temperature and time. This blueshift results from the dispersion of the labelling polymer into the labelled polymer matrix. During processing, the polyacetylene chains disentangled, thereby suppressing their intermolecular interactions. Moreover, shear forces imposed during viscous polymer melt mixing enforced conformational changes, which shortened the average conjugation length of PTMSDPA chain segments. Combined, these two mechanisms shift the luminescence of the probe from a solid- to a more solution-like state. Thus, PTMSDPA can be used as a luminescent probe for dispersion quality, polymer blend homogeneity, and processing history, in addition to the identification, tracing, and recycling of thermoplastics.

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Russell, Go M., Hiroshi Masai, and Jun Terao. "Platinum-acetylide crosslinkers for facile preparation of phosphorescent commodity polymer networks with defect-free chromophores." Materials Letters 247 (July 2019): 182–84. http://dx.doi.org/10.1016/j.matlet.2019.03.123.

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Kawecki, Delphine, and Bernd Nowack. "Polymer-Specific Modeling of the Environmental Emissions of Seven Commodity Plastics As Macro- and Microplastics." Environmental Science & Technology 53, no. 16 (July 9, 2019): 9664–76. http://dx.doi.org/10.1021/acs.est.9b02900.

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Nemoto, Tadamasa, Gen-ichi Konishi, Yusuke Tojo, Youn Chul An, and Masamitsu Funaoka. "Functionalization of lignin: Synthesis of lignophenol-graft-poly(2-ethyl-2-oxazoline) and its application to polymer blends with commodity polymers." Journal of Applied Polymer Science 123, no. 5 (August 31, 2011): 2636–42. http://dx.doi.org/10.1002/app.34623.

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Coolman, Tina, David Alexander, Rean Maharaj, and Mohammad Soroush. "An evaluation of the enhanced oil recovery potential of the xanthan gum and aquagel in a heavy oil reservoir in Trinidad." Journal of Petroleum Exploration and Production Technology 10, no. 8 (April 16, 2020): 3779–89. http://dx.doi.org/10.1007/s13202-020-00878-5.

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Abstract The economy of Trinidad and Tobago which mainly relies on its energy sector is facing significant challenges due to declining crude oil production in a low commodity price environment. The need for enhanced oil recovery (EOR) methods to meet the current and future energy demands is urgent. Studies on the use of polymer flooding in Trinidad and Tobago are limited, especially in terms of necessary data concerning the characterization of the adsorption of polymer flooding chemicals such as xanthan gum and aquagel polymers on different soil types in Trinidad and the viscosity characteristics of the polymer flooding solutions which affect the key attributes of displacement and sweep efficiency that are needed to predict recovery efficiency and the potential use of these flooding agents in a particular well. Adsorption and viscosity experiments were conducted using xanthan gum and aquagel on three different soil types, namely sand, Valencia clay (high iron) and Longdenville clay (low iron). Xanthan gum exhibited the lowest adsorption capacity for Valencia clay but absorbed most on sand at concentrations above 1000 ppm and Longdenville clay below 1000 ppm. At concentrations below 250 ppm, all three soil-type absorbent materials exhibited similar adsorption capacities. Aquagel was more significantly absorbed on the three soil types compared to xanthan gum. The lowest adsorption capacity was observed for Valencia clay at concentration levels above 500 ppm; however, the clay had the highest adsorption capacity below this level. Sand had the highest adsorption capacity for aquagel at concentrations above 500 ppm while Longdenville clay was the lowest absorbent above 500 ppm. Generally, all three soil types had a similar adsorption capacity for xanthan gum at a concentration level of 250 ppm and for aquagel at a concentration level of 500 ppm. The results offered conclusive evidence demonstrating the importance that the pore structure characteristics of soil that may be present in oil wells on its adsorption characteristics and efficiency. Xanthan gum polymer concentration of 2000 ppm, 1000 ppm and 250 ppm showed viscosities of 125 cp, 63 cp and 42 cp, respectively. Aquagel polymer concentrations of 2000 ppm, 1000 ppm and 250 ppm showed viscosities of 63 cp, 42 cp and 21 cp, respectively. Aquagel polymer solutions were found to generally have lower viscosities than the xanthan gum polymer solutions at the same concentration. Adsorption and viscosity data for the xanthan gum and aquagel polymers were incorporated within CMG numerical simulation models to determine the technical feasibility of implementing a polymer flood in the selected EOR 44 located in the Oropouche field in the southwest peninsula of the island of Trinidad. Overall, aquagel polymer flood resulted in a higher oil recovery of 0.06 STB compared to the xanthan gum polymer flood, so the better EOR method would be aquagel polymer flood. Additionally, both cases of polymer flooding resulted in higher levels of oil recovery compared to CO2 injection and waterflooding and therefore polymer flooding will have greater impact on the EOR 44 well oil recovery.

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Everaers, Ralf, Hossein Ali Karimi-Varzaneh, Frank Fleck, Nils Hojdis, and Carsten Svaneborg. "Kremer–Grest Models for Commodity Polymer Melts: Linking Theory, Experiment, and Simulation at the Kuhn Scale." Macromolecules 53, no. 6 (March 4, 2020): 1901–16. http://dx.doi.org/10.1021/acs.macromol.9b02428.

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Baumgartner, Manuel, Raphael Schaller, Paul Smith, Irene Weymuth, and Walter Caseri. "Co-Processing of [Fe(NH2trz)3](2ns)2 and UHMWPE into Materials Combining (Spin Crossover and High Mechanical Strength." Sci 2, no. 3 (August 20, 2020): 66. http://dx.doi.org/10.3390/sci2030066.

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The coordination polymer [Fe(NH2trz)3](2ns)2 exhibits the rare phenomenon of spin crossover in an attractive temperature range, i.e., somewhat above room temperature. Spin crossover in [Fe(NH2trz)3](2ns)2 is manifest by thermochromism, which is accompanied by a magnetic transition from diamagnetism to paramagnetism. However, [Fe(NH2trz)3](2ns)2 is brittle and difficult to process, which limits its use. In this study, we show that [Fe(NH2trz)3](2ns)2 can be co-processed with ultrahigh molecular weight polyethylene (UHMWPE), which possesses outstanding mechanical properties, particularly when tensile drawn. Therefore, [Fe(NH2trz)3](2ns)2–UHMWPE blends were gel-processed by extrusion, employing a relatively poor solvent, which has recently been shown to offer advantages compared to good solvents. Uniform and flexible films, ribbons and fibers with [Fe(NH2trz)3](2ns)2 fractions as high as 33.3% m/m were obtained that could be readily drawn. Spin crossover in the coordination polymer is retained in these materials, as evident from their thermochromism. The tensile strength and Young’s modulus of the blends exceed those of typical commodity polymers. Thus, the films, ribbons and fibers constitute a special class of multifunctional materials that combine the flexibility and excellent mechanical properties of drawn UHMWPE with the spin crossover behavior of [Fe(NH2trz)3](2ns)2.

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Baumgartner, Manuel, Raphael Schaller, Paul Smith, Irene Weymuth, and Walter Caseri. "Co-Processing of [Fe(NH2trz)3](2ns)2 and UHMWPE into Materials Combining (Spin Crossover and High Mechanical Strength." Sci 3, no. 1 (January 7, 2021): 7. http://dx.doi.org/10.3390/sci3010007.

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The coordination polymer [Fe(NH2trz)3](2ns)2 (NH2trz = 4-amino-1,2,4-triazole and 2ns− = counterion 2-naphthalene sulfonate) exhibits the rare phenomenon of spin crossover in an attractive temperature range, i.e., somewhat above room temperature. Spin crossover in [Fe(NH2trz)3](2ns)2 is manifested by thermochromism, which is accompanied by a magnetic transition from diamagnetism to paramagnetism. However, [Fe(NH2trz)3](2ns)2 is brittle and difficult to process, which limits its use. In this study, we show that [Fe(NH2trz)3](2ns)2 can be co-processed with ultrahigh molecular weight polyethylene (UHMWPE), which possesses outstanding mechanical properties, particularly when tensile-drawn. Therefore, [Fe(NH2trz)3](2ns)2–UHMWPE blends were gel-processed by extrusion, employing a relatively poor solvent, which has recently been shown to offer advantages compared to good solvents. Uniform and flexible films, ribbons and fibers with [Fe(NH2trz)3](2ns)2 fractions as high as 33.3% m/m were obtained that could be readily drawn. Spin crossover in the coordination polymer is retained in these materials, as evident from their thermochromism. The tensile strength and Young’s modulus of the blends exceed those of typical commodity polymers. Thus, the films, ribbons and fibers constitute a special class of multifunctional materials that combine the flexibility and excellent mechanical properties of drawn UHMWPE with the spin crossover behavior of [Fe(NH2trz)3](2ns)2.

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Ueda, Kazunari, Kazuo Tanaka, and Yoshiki Chujo. "Remarkably high miscibility of octa-substituted POSS with commodity conjugated polymers and molecular fillers for the improvement of homogeneities of polymer matrices." Polymer Journal 48, no. 12 (September 28, 2016): 1133–39. http://dx.doi.org/10.1038/pj.2016.84.

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Brebu, Mihai. "Environmental Degradation of Plastic Composites with Natural Fillers—A Review." Polymers 12, no. 1 (January 8, 2020): 166. http://dx.doi.org/10.3390/polym12010166.

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Polymer composites are widely used modern-day materials, specially designed to combine good mechanical properties and low density, resulting in a high tensile strength-to-weight ratio. However, materials for outdoor use suffer from the negative effects of environmental factors, loosing properties in various degrees. In particular, natural fillers (particulates or fibers) or components induce biodegradability in the otherwise bio inert matrix of usual commodity plastics. Here we present some aspects found in recent literature related to the effect of aggressive factors such as temperature, mechanical forces, solar radiation, humidity, and biological attack on the properties of plastic composites containing natural fillers.

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Kim, Hun Sik, Byung Hyun Park, Jin San Yoon, and Hyoung Joon Jin. "Preparation of Biodegradable Nanocomposites by Incorporation of Functionalized Carbon Nanotubes." Key Engineering Materials 326-328 (December 2006): 1785–88. http://dx.doi.org/10.4028/www.scientific.net/kem.326-328.1785.

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Polymeric carbon nanotube composites constitute one of the most promising alternatives to conventional filled polymers. The dispersion of nanometer-sized carbon nanotubes in a polymer matrix markedly improves its physical properties. This approach can also be applied to biodegradable synthetic aliphatic polyesters such as poly(L-lactic acid) (PLLA), which has been receiving an increasing amount of attention due to environmental concerns. In this study, the mechanical properties of PLLA were enhanced by the incorporation of a small amount of carbon nanotubes (0.8 wt%) in the solution state, which could make this material a good competitor for commodity materials such as general purpose plastics, while allowing it to retain its biodegradability. In order to obtain a homogeneous dispersion of the carbon nanotubes in the matrix, oxygen-containing groups were introduced on the surface of the MWNTs. The good dispersion of the nanotubes in the PLLA matrix observed by scanning electron microscopy was attributed to the fact that the PLLA was compatible with the functionalized MWNTs during the compounding process. The electrical conductivity of the composites was also investigated.

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Kanayama, Naoki, Swapan Kumar Saha, Naoki Nakayama, Jun Nakanishi, Katsuhisa Kitano, Satoshi Hamaguchi, and Yukiko Nagasaki. "Facile Creation of Biointerface on Commodity Plastic Surface by Combination of Atmospheric Plasma and Reactive Polymer Coating." Journal of Photopolymer Science and Technology 23, no. 4 (2010): 579–83. http://dx.doi.org/10.2494/photopolymer.23.579.

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Li, Fei, Xuewen Zhao, Hengti Wang, Qin Chen, Shuhua Wang, Zhenhua Chen, Xiaoyong Zhou, Wenchun Fan, Yongjin Li, and Jichun You. "Sub-100 nm Cocontinuous Structures Fabricated in Immiscible Commodity Polymer Blend with Extremely Low Volume/Viscosity Ratio." ACS Applied Polymer Materials 1, no. 2 (January 18, 2019): 124–29. http://dx.doi.org/10.1021/acsapm.8b00174.

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McMillin, Carl R. "Elastomers for Biomedical Applications." Rubber Chemistry and Technology 67, no. 3 (July 1, 1994): 417–46. http://dx.doi.org/10.5254/1.3538684.

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Abstract Over 11 percent of the gross national product of the U.S.A. is currently being spent in areas related to health care. Medical applications of polymers account for about six percent of the dollar sales of processed polymer products, or over three billion dollars annually. Medical devices, consumables, and their packaging are estimated to have used 2.3 billion pounds of polymers in 1992. This paper describes research and development within the biomedical elastomer and rubber segments of this market. Elastomers used in biomedical applications can be roughly divided into three groups; the commodity elastomers that happen to be used in the biomedical field, medical grades of elastomers that are certified for food contact or for short-term physiological contact, and a small group of elastomers that are suitable for longer-term physiological contact or implantation. Although significant from a national perspective, the many uses of commodity elastomers in the medical field will not be discussed in this paper. Some of the additional material requirements that occur when elastomers are employed in contact with biological systems include: more stringent quality control, higher purity, more controlled and cleaner manufacturing facilities, and much more additional paperwork—including information so that traceability is maintained. In most cases, the elastomers must have a degree of biocompatibility. Other specific features may also be needed, such as the ability to be sterilized by gamma irradiation or steam autoclave. Materials that are manufactured with these ends in mind are often called “medical grade.” The number of candidate materials for the high profile, implantable speciality elastomers market is considerably smaller. These elastomers must survive much more rigorous biocompatibility testing and are sometimes optimized for specific properties such as blood compatibility, extraordinary fatigue strength, or controlled biodegradability. Because there are relatively few rubbers or elastomers that are suitable for use in vivo, it is particularly significant that several of the most important of these have been withdrawn from the market because of perceived product liability issues.

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Sebati, Wilhemina, Suprakas Sinha Ray, and Richard Moutloali. "Synthesis of Porous Organic Polymer-Based Solid-Acid Catalysts for 5-Hydroxymethylfurfural Production from Fructose." Catalysts 9, no. 8 (July 31, 2019): 656. http://dx.doi.org/10.3390/catal9080656.

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Herein, we report the synthesis of nanoporous polytriphenylamine polymers (PPTPA) by a simple one-step oxidative polymerization pathway and the materials were sulfonated with chlorosulfonic acid to introduce acidic sulfonic groups to the polymers to form solid acid catalysts (SPPTPA). Magnetic properties were added to SPPTPA catalysts by depositing Fe3O4 nanoparticles to develop (FeSPPTPA) solid acid catalysts, for performing dehydration of fructose to 5-hydroxymethylfurfural (HMF), which is regarded as a sustainable source for liquid fuels and commodity chemicals. XRD, FTIR spectroscopy, SEM, TGA, and N2 sorption techniques were used to characterize synthesized materials. The FeSPPTPA80 nanocatalyst showed superior catalytic activities in comparison to other catalysts due to the nanorods that formed after sulfonation of the PPTPA polymeric material which gave the catalyst enough catalytic centers for dehydration reaction of fructose. The recyclability tests revealed that the magnetic solid acid catalysts could be reused for four consecutive catalytic runs, which made FeSPPTPA a potential nanocatalyst for production of HMF.

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Constant-Mandiola, Benjamin, Héctor Aguilar-Bolados, Julian Geshev, and Raul Quíjada. "Study of the Influence of Magnetite Nanoparticles Supported on Thermally Reduced Graphene Oxide as Filler on the Mechanical and Magnetic Properties of Polypropylene and Polylactic Acid Nanocomposites." Polymers 13, no. 10 (May 18, 2021): 1635. http://dx.doi.org/10.3390/polym13101635.

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A study addressed to develop new recyclable and/or biodegradable magnetic polymeric materials is reported. The selected matrices were polypropylene (PP) and poly (lactic acid) (PLA). As known, PP corresponds to a non-polar homo-chain polymer and a commodity, while PLA is a biodegradable polar hetero-chain polymer. To obtain the magnetic nanocomposites, magnetite supported on thermally reduced graphene oxide (TrGO:Fe3O4 nanomaterial) to these polymer matrices was added. The TrGO:Fe3O4 nanomaterials were obtained by a co-precipitation method using two types of TrGO obtained by the reduction at 600 °C and 1000 °C of graphite oxide. Two ratios of 2.5:1 and 9.6:1 of the magnetite precursor (FeCl3) and TrGO were used to produce these nanomaterials. Consequently, four types of nanomaterials were obtained and characterized. Nanocomposites were obtained using these nanomaterials as filler by melt mixer method in polypropylene (PP) or polylactic acid (PLA) matrix, the filler contents were 3, 5, and 7 wt.%. Results showed that TrGO600-based nanomaterials presented higher coercivity (Hc = 8.5 Oe) at 9.6:1 ratio than TrGO1000-based nanomaterials (Hc = 4.2 Oe). PLA and PP nanocomposites containing 7 wt.% of filler presented coercivity of 3.7 and 5.3 Oe, respectively. Theoretical models were used to analyze some relevant experimental results of the nanocomposites such as mechanical and magnetic properties.

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Beach, Evan S., Brian R. Weeks, Rebecca Stern, and Paul T. Anastas. "Plastics additives and green chemistry." Pure and Applied Chemistry 85, no. 8 (January 5, 2013): 1611–24. http://dx.doi.org/10.1351/pac-con-12-08-08.

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The plastics enterprise depends on a small number of commodity polymers to perform in diverse applications, requiring additives to produce desired properties and performance. Toxic effects and environmental persistence of certain additive chemicals impact the sustainability of the industry. Green chemistry has been and will continue to be applied to find solutions to these issues. This review focuses on alternatives to phthalate plasticizers and halogenated flame retardants, two categories that together account for a significant portion of the global additives market and the global dispersion of endocrine-disrupting chemicals. Small-molecule alternatives that exist in various stages of research and commercialization will be discussed, with emphasis on the use of renewable resources. The rise of biorefineries and new bio-based monomers may help overcome existing economic barriers to adoption of alternatives. Increasing the molecular weight of additives or covalently linking them to polymer backbones are two promising strategies for reducing both mobility and toxicity that will also be discussed. Finally, the design of new polymers that show desirable properties without the use of additives will be considered. The substances put forward as “green” alternatives have yet to receive the same level of scrutiny as diethylhexyl phthalate (DEHP, also known as dioctyl phthalate) or polybrominated diphenyl ethers (PBDEs). Cooperation between chemists, engineers, and the environmental health community will be critical to ensure the safety and sustainability of new technologies.

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Williams, Rhys J., Luke Fox, and Candice Majewski. "The effect of powder age in high speed sintering of poly(propylene)." Rapid Prototyping Journal 27, no. 4 (May 10, 2021): 707–19. http://dx.doi.org/10.1108/rpj-05-2020-0090.

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Purpose This study aims to demonstrate for the first time that the cheap, commodity polymer, poly(propylene), can be successfully processed using high speed sintering, and that it can be recycled several times through the process, with little to no detriment to either the polymer itself or the parts obtained. This is significant as a step towards the realisation of high speed sintering as a technology for high-volume manufacturing. Design/methodology/approach A poly(propylene) powder designed for laser sintering was used to build parts on a high speed sintering machine. The unsintered powder was then collected and reused. Repeating this process allowed creation of seven generations of aged powder. A variety of characterisation techniques were then used to measure polymer, powder and part properties for each generation to discern any effects arising from ageing in the machine. Findings It was found that poly(propylene) could be used successfully in high speed sintering, albeit with a low build success rate. Increased powder age was found to correlate to an increase in the build success rate, changes in microscopic and bulk powder properties and improvement to the dimensional accuracy of the parts obtained. By contrast, no discernible correlations were seen between powder age and polymer molecular weight, or between powder age and the tensile properties of parts. Originality/value This is the first report of the use of poly(propylene) in high speed sintering. It is also first study regarding powder recyclability in high speed sintering, both in general and using poly(propylene) specifically.

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Mohapi, Maleshoane, Jeremia Shale Sefadi, Mokgaotsa Jonas Mochane, Sifiso Innocent Magagula, and Kgomotso Lebelo. "Effect of LDHs and Other Clays on Polymer Composite in Adsorptive Removal of Contaminants: A Review." Crystals 10, no. 11 (October 22, 2020): 957. http://dx.doi.org/10.3390/cryst10110957.

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Recently, the development of a unique class of layered silicate nanomaterials has attracted considerable interest for treatment of wastewater. Clean water is an essential commodity for healthier life, agriculture and a safe environment at large. Layered double hydroxides (LDHs) and other clay hybrids are emerging as potential nanostructured adsorbents for water purification. These LDH hybrids are referred to as hydrotalcite-based materials or anionic clays and promising multifunctional two-dimensional (2D) nanomaterials. They are used in many applications including photocatalysis, energy storage, nanocomposites, adsorption, diffusion and water purification. The adsorption and diffusion capacities of various toxic contaminants heavy metal ions and dyes on different unmodified and modified LDH-samples are discussed comparatively with other types of nanoclays acting as adsorbents. This review focuses on the preparation methods, comparison of adsorption and diffusion capacities of LDH-hybrids and other nanoclay materials for the treatment of various contaminants such as heavy metal ions and dyes.

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Shuang, Fu, Xia Chunhui, Li Hongmei, and Xu Feng. "The Synthesis of New Solid-phase Microextraction Adsorption Material and Its Adsorption Performance." Open Chemical Engineering Journal 9, no. 1 (June 26, 2015): 53–57. http://dx.doi.org/10.2174/1874123101509010053.

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This article uses three kinds of monomers: the styrene, butyl acrylate and Vinyltriisopropoxysilane, synthesized the solid phase micro extract coating adsorption material, carries on the structure characterization and the physical performance test. Takes it as the solid phase micro extract coating, carries on the inspection to its adsorbability, the experiment obtains the detection limit of the benzene which is 0.21 µ g/L; The detection limit of the toluene is 30 µ g/L; The detection limit of the m-Xylene is 0.55 µ g/L. Indicated the adsorptivity of this polymer has more effection toward the small molecular aromatic hydrocarbon as the solid phase micro extract coating adsorption material, and the limit of detection is lower compared to the commodity extract coating, there are some promotion and adoption value.

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Siddiquee, Aleena Naseer, Swati Varshney, Kanwarjeet Singh, and Gaurav Arora. "Recycled polypropylene Tiles: - From waste to wealth." INTERNATIONAL JOURNAL OF ADVANCED PRODUCTION AND INDUSTRIAL ENGINEERING 4, no. 1 (January 5, 2019): 16–18. http://dx.doi.org/10.35121/ijapie201901133.

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The main objective of this research work is the development of multipurpose light weight polypropylene (PP) tiles by injection moulding technique from recycled polypropylene. The base material selected for this product is polypropylene (PP) which is a common thermoplastic commodity plastic having melting point of 140°C. PP is a polymer material that offers good quality of elasticity, toughness, high mechanical strength with great aesthetic properties. Various compositions of recycled PP composite along with PP copolymer and acrylo butadiene styrene (ABS) have been formulated. These recycled composite materials have been processed by an injection molding machine to tiles and characterized for various properties to confirm its feasibility for commercial application. PP tiles having PP copolymer and ABS shows highest value to tensile strength i.e. 36.2 N/mm2. These tiles can be used as a better substitute in order to replace conventional tiles and can also resolves plastic land filling problem

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Ali, Emad, and Mohamed Hadj-Kali. "Energy efficiency analysis of styrene production by adiabatic ethylbenzene dehydrogenation using exergy analysis and heat integration." Polish Journal of Chemical Technology 20, no. 1 (March 1, 2018): 35–46. http://dx.doi.org/10.2478/pjct-2018-0006.

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Abstract Styrene is a valuable commodity for polymer industries. The main route for producing styrene by dehydrogenation of ethylbenzene consumes a substantial amount of energy because of the use of high-temperature steam. In this work, the process energy requirements and recovery are studied using Exergy analysis and Heat Integration (HI) based on Pinch design method. The amount of steam plays a key role in the trade-off between Styrene yield and energy savings. Therefore, optimizing the operating conditions for energy reduction is infeasible. Heat integration indicated an insignificant reduction in the net energy demand and exergy losses, but 24% and 34% saving in external heating and cooling duties, respectively. When the required steam is generated by recovering the heat of the hot reactor effluent, a considerable saving in the net energy demand, as well as the heating and cooling utilities, can be achieved. Moreover, around 68% reduction in the exergy destruction is observed.

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Hollerová, Aneta, Nikola Hodkovicová, Jana Blahová, Martin Faldyna, Petr Maršálek, and Zdeňka Svobodová. "Microplastics as a potential risk for aquatic environment organisms – a review." Acta Veterinaria Brno 90, no. 1 (2021): 99–107. http://dx.doi.org/10.2754/avb202190010099.

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In the modern world, plastic has become a major commodity on global scale and is presented in all life aspects. The production of plastics is increasing dramatically throughout the world and is considered to be a serious threat for the aquatic environment. Scientists started to raise questions as to where all the disappeared plastic debris had gone, as the plastic material is a persistent synthetic polymer. The disappearance of plastic suggests that microplastics are generated by fragmentation of larger plastic debris. They also enter the aquatic environment from the cosmetics, clothing, and other industrial manufacturing. Microplastic particles spread in the aquatic, terrestrial, and atmospheric environments due to their small size and ubiquity, showing their high bioavailability. The presence of microplastics has been demonstrated in the digestive tracts of most aquatic organisms at various trophic levels. Evidence of negative effects of microplastics has been found in relation to fertility, mortality, oxidative stress, immune system or metabolic processes.

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Kesters, Els, Q. T. Le, D. Yu, M. Shen, S. Braun, A. Klipp, and F. Holsteyns. "Post Etch Residue Removal and Material Compatibility in BEOL Using Formulated Chemistries." Solid State Phenomena 219 (September 2014): 201–4. http://dx.doi.org/10.4028/www.scientific.net/ssp.219.201.

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A possible way to realize a 22.5 nm 1⁄2 pitch and beyond BEOL interconnect structures within the low-kmaterial is the partial-trench via first with self-aligned double patterning (SADP) integration approach. A scheme of this BEOL integration stack with the different materials used after patterning is described in Figure 1. In BEOL processing, fluorocarbon-containing plasma is commonly used to pattern silica-based dielectric layers. During the patterning of the low-kdielectric layer, a thin layer of fluoropolymer (CFx-type residues) is intentionally deposited on the dielectric sidewalls and TiN hardmask to ensure anisotropic etching and prevent/minimize dielectric degradation. This polymer layer must be removed from the sidewall and the via bottom prior to the subsequent processing steps to achieve good adhesion and coverage of materials deposited in the etched features. The compatibility requirement is even more stringent for advanced low-kdielectrics, i.e. materials with lowerk-value and higher porosity. The post etch residue (PER) amount and properties are specific and depend on the stack structure and the plasma that is used for patterning. The low-kmaterials and hardmasks that are used in this work are respectively an organo-silicate glass (OSG) type of low-kmaterial withk= 2.4 (~20 % open porosity) and low-stress TiN. Recent results clearly showed the presence of a highly fluorinated layer deposited on the trench sidewalls during the plasma etch based on a fluorocarbon plasma [1-3]. Commodity aqueous cleaning solutions, such as diluted HF, do not efficiently remove the sidewall polymers without etching the underlying layer (lift-off). Therefore, there is a need for commercially available chemicals that can be easily tuned to deal with the different requirements. This study focuses on the use of FOTOPUR® R 2300 mixed with H2O2 for polymer residue removal selectively to other materials (presented in the stack) such as MHM, metals (Cu, W), and porous low-k dielectrics. We will show that TiN etch can be easily tuned by changing the concentration of H2O2.

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Tosif, Mansuri M., Agnieszka Najda, Aarti Bains, Grażyna Zawiślak, Grzegorz Maj, and Prince Chawla. "Starch–Mucilage Composite Films: An Inclusive on Physicochemical and Biological Perspective." Polymers 13, no. 16 (August 4, 2021): 2588. http://dx.doi.org/10.3390/polym13162588.

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In recent years, scientists have focused on research to replace petroleum-based components plastics, in an eco-friendly and cost-effective manner, with plant-derived biopolymers offering suitable mechanical properties. Moreover, due to high environmental pollution, global warming, and the foreseen shortage of oil supplies, the quest for the formulation of biobased, non-toxic, biocompatible, and biodegradable polymer films is still emerging. Several biopolymers from varied natural resources such as starch, cellulose, gums, agar, milk, cereal, and legume proteins have been used as eco-friendly packaging materials for the substitute of non-biodegradable petroleum-based plastic-based packaging materials. Among all biopolymers, starch is an edible carbohydrate complex, composed of a linear polymer, amylose, and amylopectin. They have usually been considered as a favorite choice of material for food packaging applications due to their excellent forming ability, low cost, and environmental compatibility. Although the film prepared from bio-polymer materials improves the shelf life of commodities by protecting them against interior and exterior factors, suitable barrier properties are impossible to attain with single polymeric packaging material. Therefore, the properties of edible films can be modified based on the hydrophobic–hydrophilic qualities of biomolecules. Certain chemical modifications of starch have been performed; however, the chemical residues may impart toxicity in the food commodity. Therefore, in such cases, several plant-derived polymeric combinations could be used as an effective binary blend of the polymer to improve the mechanical and barrier properties of packaging film. Recently, scientists have shown their great interest in underutilized plant-derived mucilage to synthesize biodegradable packaging material with desirable properties. Mucilage has a great potential to produce a stable polymeric network that confines starch granules that delay the release of amylose, improving the mechanical property of films. Therefore, the proposed review article is emphasized on the utilization of a blend of source and plant-derived mucilage for the synthesis of biodegradable packaging film. Herein, the synthesis process, characterization, mechanical properties, functional properties, and application of starch and mucilage-based film are discussed in detail.

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Kim, Hun Sik, Byung Hyun Park, Yun Seok Chae, Jin San Yoon, and Hyoung Joon Jin. "Preparation and Characterization of Poly(ε-Caprolactone)/Multiwalled Carbon Nanotube Composites." Key Engineering Materials 342-343 (July 2007): 737–40. http://dx.doi.org/10.4028/www.scientific.net/kem.342-343.737.

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In this study, poly(ε-caprolactone) (PCL)/multiwalled carbon nanotube (MWCNT) composites with different contents of MWCNTs were successfully prepared by solution compounding, a method which could make them good competitors for commodity materials such as general purpose plastics, while allowing them to keep their complete biodegradability. For the homogeneous dispersion of the MWCNTs in the polymer matrix, oxygen-containing groups were introduced on their surface. The mechanical properties of the PCL/MWCNT composites were effectively increased due to the incorporation of the MWCNTs. The composites were characterized using scanning electron microscopy, in order to obtain information on the dispersion of the MWCNTs in the polymeric matrix. In the case of the composites containing 2.0 wt% of MWCNTs in their matrix, the strength and modulus of the composites were increased by 18.4% and 178.4%, respectively. In addition, the dispersion of the MWCNTs in the PCL matrix resulted in a substantial decrease in the electrical resistivity of the composites as the MWCNT loading was increased from 0 to 2.0 wt%.

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PANDEY, JITENDRA KUMAR, and HITOSHI TAKAGI. "SELF HEALING POTENTIAL OF GREEN NANOCOMPOSITES FROM CRYSTALLINE CELLULOSE." International Journal of Modern Physics B 25, no. 31 (December 20, 2011): 4216–19. http://dx.doi.org/10.1142/s0217979211066611.

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In plant cell walls, stiff semicrystalline nano dimensional cellulose microfibrils are embedded in a pliable amorphous matrix where the size and shape of the cellulose fibrils are controlled by the dimensions of crystalline regions, providing them a unique structural and physical combination to be applied as load-bearing constituent in composites. The qualities such as specific orientation under magnetic field, extraction through simple process, abundantly available source from nature and desirable modifications have deliberately directed the intense research efforts in a number of disciplines ranging from commodity to higher applications, not only in the area of high performance polymer based composites but also to develop biosensors, magnetic strips and optical devices. The present work is focused on the use of cellulose nano-fillers for creating the self-healing function and their effect on material properties of resulting composites. The present work is in initial stage and reviews the use of cellulose nano-fillers for creating the self-healing function and their effect on material properties of resulting composites.

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Brzęk, Paweł, and Tomasz Sterzyński. "Stress Whitening as an Observation Method of Residual Stress in MABS Polymer Material through the Example of Holding Pressure in an Injection Molding Process." Polymers 12, no. 12 (November 30, 2020): 2871. http://dx.doi.org/10.3390/polym12122871.

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The effects such as warpage, dimensional instability and environmental stress corrosion, due to the presence of residual stresses in polymeric products, are strongly dependent on injection molding conditions. The holding time and holding pressure belongs to most important processing parameters, determining the dimensional stability and properties of injected goods. A new procedure based on a visualization technique was applied, where the levels of residual stresses of the samples were estimated. The experiments were performed for samples produced of translucent methacrylate acrylonitrile butadiene styrene (MABS), a commodity polymer with a high transparency, necessary for the optical visualization of the stress whitening. The samples produced by injecting molding were deformed to a constant elongation, to observe the dependent stress whitening effect subsequently used to evaluate the stress distribution. It was found that depending on the value of the injection holding pressure, various levels of residual stress and its distribution may be observed in MABS samples. These measurements conformed that the applied optical method is an easy-to-perform technique. The possibility to detect the residual stresses over the whole cross-section of the transparent product, without the necessity for local stress determination, is another significant advantage of this investigation procedure.

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Journal articles on the topic 'Commodity polymer'

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