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Journal articles on the topic 'Polycondensation catalist'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 June 2024

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1

Guan, Zhenyu, Jialong Zhang, Wenle Zhou, et al. "Mechanistic Details of the Titanium-Mediated Polycondensation Reaction of Polyesters: A DFT Study." Catalysts 13, no. 10 (2023): 1388. http://dx.doi.org/10.3390/catal13101388.

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In this work, the mechanism of polyester polycondensation catalysed by titanium catalysts was investigated using density functional theory (DFT). Three polyester polycondensation reaction mechanisms, including the Lewis acid mechanism (M1), the coordination of the ester alkoxy oxygen mechanism (M2) and the coordination of the carboxy oxygen mechanism (M3), were investigated. Three reaction mechanisms for the polycondensation reaction of diethyl terephthalate (DET) were investigated using Ti(OEt)4 and cationic Ti(OEt)3+ as the catalyst. The results show that the polycondensation reaction of the

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2

Pospiech, Doris, Renata Choińska, Daniel Flugrat, et al. "Enzymatic Synthesis of Poly(alkylene succinate)s: Influence of Reaction Conditions." Processes 9, no. 3 (2021): 411. http://dx.doi.org/10.3390/pr9030411.

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Application of lipases (preferentially Candida antarctica Lipase B, CALB) for melt polycondensation of aliphatic polyesters by transesterification of activated dicarboxylic acids with diols allows to displace toxic metal and metal oxide catalysts. Immobilization of the enzyme enhances the activity and the temperature range of use. The possibility to use enzyme-catalyzed polycondensation in melt is studied and compared to results of polycondensations in solution. The experiments show that CALB successfully catalyzes polycondensation of both, divinyladipate and dimethylsuccinate, respectively, w

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3

Hwang, Sung Yeon, Dong Yeop X. Oh, and Je Young Park. "Synthesis of High Molecular Weight Poly(L-Lactic Acid)s by Direct Polycondensation with Organic Acids as Catalyst." Key Engineering Materials 773 (July 2018): 25–29. http://dx.doi.org/10.4028/www.scientific.net/kem.773.25.

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In this study, high molecular weight (HMW) poly (l-lactic acid)s (PLLAs) were synthesized by direct polycondensation using organic acid catalysts alone in a nitrogen-controlled environment. The melting point and enthalpy of the pre-polymer produced by melt polycondensation increased as molecular weight grew during solid-state polycondensation. It was observed that the nitrogen-controlled external environment had lower molecular weight than air, but the low molecular weight tail was significantly reduced, as indicated by gel permeation chromatography. This is because it inhibited the reverse re

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4

Ochiai, Bungo, and Yuriko Kobayashi. "Non-Isocyanate Synthesis of Aliphatic Polyurethane by BiCl3-Catalyzed Transurethanization Polycondensation." Polymers 16, no. 8 (2024): 1136. http://dx.doi.org/10.3390/polym16081136.

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Non-isocyanate polyurethane synthesis by non-Sn catalysis is an essential challenge toward green polyurethane synthesis. Bismuth compounds are attractive candidates due to their low cost, low toxicity, and availability to urethane chemistry. This work applied various Bi catalysts to the self-polycondensation of a bishydroxyurethane monomer and found BiCl3 to be an excellent catalyst through optimization. The catalytic activity and price of BiCl3 are comparable to those of Bu2SnO, while its toxicity is significantly low. BiCl3 is, therefore, a promising alternative to Sn-based catalysts in non-

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5

Zou, Wenqi, Hongli Bian, Jinjing Guo, Jun Xu, and Baohua Guo. "Preparation of Titania–Silica Composite Aerogel at Atmospheric Pressure and Its Catalytic Performance in the Synthesis of Poly (Butylene Succinate)." Materials 16, no. 9 (2023): 3296. http://dx.doi.org/10.3390/ma16093296.

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Titanates are widely used in the synthesis of polyesters, such as Poly (butylene succinate) (PBS), due to their excellent catalytic activity for polycondensation. However, the hydrolysis sensitivity of titanate and side reactions at high temperatures restrict the further improvement of the molecular weight of polyesters and lead to the high content of end carboxyl group content in the products. In this work, we prepared titania–silica composite aerogels with resistance to hydrolysis and large specific surface area, which were further explored as an efficient catalyst for polycondensation react

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6

Sui, Aiguo, Xincui Shi, Yongxia Wang, Yanhou Geng, and Fosong Wang. "Kumada catalyst transfer polycondensation for controlled synthesis of polyfluorenes using 1,3-bis(diarylphosphino)propanes as ligands." Polymer Chemistry 6, no. 26 (2015): 4819–27. http://dx.doi.org/10.1039/c5py00610d.

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7

Duan, Haonan, Zanyao Niu, and Xiaoqi Yang. "Physical Properties of Cyclic Esters and its Application in Heterogeneous Electrocatalysis." Journal of Physics: Conference Series 2083, no. 2 (2021): 022083. http://dx.doi.org/10.1088/1742-6596/2083/2/022083.

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Abstract Oxygen reduction is a key reaction in many energy conversion devices. Phosphorus-containing porous organic polymers not only have developed pores and surface structure, but also have strong adjustable modification and modification, so they have a wide application prospect in heterogeneous catalysis. At present, the preparation of phosphorus-containing porous organic polymers and their applications in heterogeneous catalysis have not been reviewed. in this paper, the research progress in this field in the past decade is summarized and reviewed. The synthetic methods of phosphorus-conta

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8

El Fray, Miroslawa, Michal Rybko, and Agnieszka Piegat. "Silica-Polyester Nanocomposites Prepared by Polycondensation In Situ: Synthesis and Mechanical Properties." Materials Science Forum 714 (March 2012): 277–82. http://dx.doi.org/10.4028/www.scientific.net/msf.714.277.

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New multiblock polymer-matrix nanocomposites were prepared by the in situ polycondensation. Polymers containing 30% hard segments of poly (butylene terephthalate) (PBT) and 70% soft segments built up from dimerized fatty acid (DLA), were modified with silica nanopowder. The nanocomposite materials were prepared by polycondensation in situ with the use of two different catalysts. Two types of nanosilica (Evonic Aerosil R 972 hydrophobic, and Aerosil 130 - hydrophilic) in amount of 0.1, 0.2 and 0.3 wt. % were used. Physical and mechanical properties were examined. The results indicate a strong i

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9

Hong, Chae Hwan, Si Hwan Kim, Ji-Yeon Seo, and Do Suck Han. "Development of Four Unit Processes for Biobased PLA Manufacturing." ISRN Polymer Science 2012 (March 15, 2012): 1–6. http://dx.doi.org/10.5402/2012/938261.

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Polylactide (PLA), which is one of the most important biocompatible polyesters that are derived from annually renewable biomass such as corn and sugar beets, has attracted much attention for automotive parts application. The manufacturing method of PLA is the ring-opening polymerization of the dimeric cyclic ester of lactic acid, lactide. For the stereocomplex PLA, we developed the four unit processes, fermentation, separation, lactide conversion, and polymerization. Fermentation of sugars to D-lactic acid is little studied, and its microbial productivity is not well known. Therefore, we inves

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10

Babić, B., Velimir Radmilović, N. Krstajić, and B. Kaludjerović. "Electrooxidation of Hydrogen on Nanostructured Pt/C Catalysts for Polymer Electrolyte Fuel Cells." Materials Science Forum 518 (July 2006): 283–88. http://dx.doi.org/10.4028/www.scientific.net/msf.518.283.

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Mesoporous carbon cryogel synthesized by sol-gel polycondensation and freeze-drying with specific surface area (BET) of 517 m2 g-1 was used as a catalyst support. Pt/C catalysts were prepared by a modified ethylene glycol method (EG). Transmission electron microscopy (TEM) images show that the dispersion of the catalyst is very uniform with a mean particle size of about 2.65 nm. Hydrogen oxidation reaction (HOR) was studied on Pt/C catalyst in 0.5 mol dm-3 HClO4 acid solution. It has been found that HOR appears as a reversible two-electron direct discharged reaction (Tafel slope for this react

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11

Alegre, C., M. E. Gálvez, D. Sebastián, R. Moliner, and M. J. Lázaro. "Influence of Synthesis pH on Textural Properties of Carbon Xerogels as Supports for Pt/CXs Catalysts for Direct Methanol Fuel Cells." International Journal of Electrochemistry 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/267893.

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Carbon xerogels (CXs) have been prepared by polycondensation of resorcinol and formaldehyde. Two synthesis pHs were studied in order to evaluate its influence on the electrochemical behaviour of Pt catalysts supported on previous carbon xerogels, synthesized by conventional impregnation method. Catalysts were also synthesized over a commercial carbon black (Vulcan-XC-72R) for comparison purposes. Characterization techniques included nitrogen physisorption, scanning electron microscopy, and X-ray diffraction. Catalysts electrochemical activity towards the oxidation of carbon monoxide and methan

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12

Kiciński, Wojciech, and Sławomir Dyjak. "Nitrogen-Doped Carbons Derived from Imidazole-Based Cross-Linked Porous Organic Polymers." Molecules 26, no. 3 (2021): 668. http://dx.doi.org/10.3390/molecules26030668.

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Nitrogen-doped and heteroatom multi-doped carbon materials are considered excellent metal-free catalysts, superior catalyst supports for transition metal particles and single metal atoms (single-atom catalysts), as well as efficient sorbents for gas- and liquid-phase substances. Acid-catalyzed sol–gel polycondensation of hydroxybenzenes with heterocyclic aldehydes yields cross-linked thermosetting resins in the form of porous organic polymers (i.e., organic gels). Depending on the utilized hydroxybenzene (e.g., phenol, resorcinol, phloroglucinol, etc.) and heterocyclic aldehyde variety of hete

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13

Kadiev, Khusain M., Anton L. Maximov, and Malkan Kh Kadieva. "The Effect of MoS2 Active Site Dispersion on Suppression of Polycondensation Reactions during Heavy Oil Hydroconversion." Catalysts 11, no. 6 (2021): 676. http://dx.doi.org/10.3390/catal11060676.

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In this work, the composition, structural and morphological features, and particle size of the active phase of the catalyst (MoS2), synthesized in-situ during the heavy oil hydroconversion performed in continuous flow reactor on lab-scale pilot flow unit at T = 450 °C, P = 6.0–9.0 MPa, V = 1.0 h−1, H2/feed = 1000 nL/L, catalyst concentration C (Mo) = 0.01–0.08%wt have been studied. It has been shown that MoS2 formed during hydroconversion is represented by nanosized particles stabilized by polycondensation products as a result of strong adsorption and aggregation with the components of the hyd

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14

Cheng, Yu-Wei, Tar-Hwa Hsieh, Yu-Chang Huang, et al. "Calcined Co(II)-Chelated Polyazomethine as Cathode Catalyst of Anion Exchange Membrane Fuel Cells." Polymers 14, no. 9 (2022): 1784. http://dx.doi.org/10.3390/polym14091784.

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Polyazomethine (PAM) prepared from the polycondensation between p-phenylene diamine (PDA) and p-terephthalaldehyde (PTAl) via Schiff reaction can physically crosslink (complex) with Co ions. Co-complexed PAM (Co-PAM) in the form of gel is calcined to become a Co, N-co-doped carbonaceous matrix (Co-N-C), acting as cathode catalyst of an anion exchange membrane fuel cell (AEMFC). The obtained Co-N-C catalyst demonstrates a single-atom structure with active Co centers seen under the high-resolution transmission electron microscopy (HRTEM). The Co-N-C catalysts are also characterized by XRD, SEM,

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15

Zhou, Qiao, Yuanyuan Zhao, Yafei Shi, Rongrong Zheng, and Liying Guo. "Acidic Metal-Based Functional Ionic Liquids Catalyze the Synthesis of Bio-Based PEF Polyester." Polymers 16, no. 1 (2023): 103. http://dx.doi.org/10.3390/polym16010103.

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Utilizing triethylenediamine (DA), 1,3-propanesultone (PS), whose ring opens during the formation of the dizwiterion-intermediate DA-2PS, and the metal chlorides XCly, where X = Sn(IV), Zn(II),Al(III), Fe(III) and Mn(II), are used for the synthesis of five kinds of acidic metal-based functionalized ionic liquid catalysts ([DA-2PS][XCly]2). Their chemical structures, thermal stability and dual acidic active site were analyzed. We investigated the performance of [DA-2PS][XCly]2 in catalyzing the esterification reaction between 2,5-furandicarboxylic acid (FDCA) and ethylene glycol (EG) to synthes

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16

Shi, Xincui, Aiguo Sui, Yongxia Wang, Yuesheng Li, Yanhou Geng, and Fosong Wang. "Controlled synthesis of high molecular weight poly(3-hexylthiophene)s via Kumada catalyst transfer polycondensation with Ni(IPr)(acac)2 as the catalyst." Chemical Communications 51, no. 11 (2015): 2138–40. http://dx.doi.org/10.1039/c4cc08012b.

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17

Ye, Shuyang, Scott M. Foster, Adam A. Pollit, Susan Cheng та Dwight S. Seferos. "The role of halogens in the catalyst transfer polycondensation for π-conjugated polymers". Chemical Science 10, № 7 (2019): 2075–80. http://dx.doi.org/10.1039/c8sc04808h.

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18

Shakhmurzova, K. T., Zh I. Kurdanova, Arthur E. Baikaziev, Karina Kh Teunova, Azamat A. Zhansitov, and S. Yu Khashirova. "Methods for the Synthesis of Polyethereketone." Materials Science Forum 935 (October 2018): 27–30. http://dx.doi.org/10.4028/www.scientific.net/msf.935.27.

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The data on the methods for the preparation of polyetherketones by electrophilic and nucleophilic methods are considered and generalized. It is shown that polyetherketones by electrophilic substitution are carried out as homopolycondensation aromatic monocarboxylic acids and their halides and polycondensation of polynuclear aromatic hydrocarbons with aromatic dicarboxylic acids or their halides, and phosgene in organic solvents (1,2-dichloroethane, methylene chloride, nitrobenzene and etc.) in the presence of Ziegler-Natt catalysts. However, this process has not found an industrial application

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19

Ávila-Niño, José A., and Lilian I. Olvera. "Ionic self-assembled organogel polyelectrolytes for energy storage applications." RSC Advances 10, no. 20 (2020): 11743–49. http://dx.doi.org/10.1039/d0ra00825g.

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20

Lu, Shi Chao, Yang Chuan Ke, Qian Zhou, et al. "Study on the Preparation and Characterization of Carboxyl Terminated Poly(L-Lactic Acid) (PLLA) Prepolymers." Applied Mechanics and Materials 872 (October 2017): 165–70. http://dx.doi.org/10.4028/www.scientific.net/amm.872.165.

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The carboxyl terminated poly (L-lactic acid) (PLLA) prepolymers were prepared via polycondensation of L-lactic acid and 1,6-adipic acid (end capping agent) under the catalyst of stannous octoate. The effects of synthetic condition, such as reaction temperature, amount of catalyst, content of the end capping agent, etc, on the molecular weight of PLLA were discussed. Fourier transform infrared and 1H nuclear magnetic resonance were used to characterize the PLLA prepolymers. The results indicated that the polycondensation was performed under an optimum reaction condition as following: the amount

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21

Zuhdan, Jayyid, Aisyah Zahidah Rohmah, Nuniek Hendriani, Hikmatun Ni'mah, Siti Nurkhamidah, and Tri Widjaja. "Characterization and Comparison of Various Lewis Acid Surfactant Combined Catalyst (LASC) and Their Potential for Polylactic Acid Synthesis by Polycondensation." Materials Science Forum 1057 (March 31, 2022): 65–70. http://dx.doi.org/10.4028/p-s44248.

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In Polylactic acid (PLA) production, there is a byproduct in the form of water, while Lewis acid catalysts such as Al(III), Ti(IV), and Sn(IV) which is commonly used for PLA production will be rapidly decomposed and deactivated by water. The aim for this research was to synthesize a Lewis acid water-tolerant catalyst called LASC (Lewis Acid Surfactant Combined Catalyst) by combining some Lewis metals with surfactant in the form of Sodium dodecyl sulfate (SDS) which will bind each other to become Fe(dodecyl sulfate)3 [Fe(DS)3], Al(dodecyl sulfate)3 [Al(DS)3], and Cu(dodecyl sulfate)2 [Cu(DS)2]

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22

Yoon, Hyoung-Ju, Jae Young Lee, Jae-Suk Lee, and Tae-Ho Yoon. "Monolithic carbon xerogel with co-continuous hierarchical porosity via one-step, template- and catalyst-free hydrothermal reaction with resorcinol and formaldehyde." RSC Advances 9, no. 17 (2019): 9480–85. http://dx.doi.org/10.1039/c9ra00904c.

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Monolithic carbon xerogel (MCX) with co-continuous hierarchical porosity was prepared via a one-step, template- and catalyst-free hydrothermal polycondensation reaction with resorcinol, formaldehyde and distilled water.

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23

Liu, Huai-Hsuan, Wei-Wei Liang, Yu-Ying Lai, et al. "Synthesis of side-chain regioregular and main-chain alternating poly(bichalcogenophene)s and an ABC-type periodic poly(terchalcogenophene)." Chemical Science 11, no. 15 (2020): 3836–44. http://dx.doi.org/10.1039/d0sc00404a.

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Three unsymmetrical diiodobichalcogenophenes SSeI2, STeI2, and SeTeI2 and a diiodoterchalcogenophene SSeTeI2 were prepared to synthesize a new class of polychalcogenophenes with precisely controlled sequences by catalyst-transfer polycondensation.

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24

Harrypersad, Shane, and Daniel Foucher. "Alternating polystannanes: syntheses and properties." Chemical Communications 51, no. 33 (2015): 7120–23. http://dx.doi.org/10.1039/c5cc00568j.

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The catalyst free stoichiometric polycondensation reaction of alkyl or aryl tin dihydrides and tin diamides in non-polar solvents and mild reaction conditions yields the first examples of alternating polystannanes.

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25

Lei, Xing, Gui Long Xu, Jin Yang, and Jian Hu. "Study of Molecular Structure of Water-Soluble Phenolic Resin with Different Molecular Weight by Infrared Spectrum." Advanced Materials Research 900 (February 2014): 15–19. http://dx.doi.org/10.4028/www.scientific.net/amr.900.15.

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Water-soluble phenolic resin was prepared using sodium hydroxide and ammonia as catalysts. The molecular structure of water-soluble phenolic with different molecular weight was studied by infrared spectrum and the mechanism was discussed. The results show that addition reaction and polycondensation synchronize in the reaction process, while addition reaction dominates in the early stage while polycondensation dominates in the later stage.

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26

Shen, Kai, and Sheng Lin Yang. "Preparation of High-Molecular-Weight Poly(glycolic acid) by Direct Melt Polycondensation from Glycolic Acid." Advanced Materials Research 821-822 (September 2013): 1023–26. http://dx.doi.org/10.4028/www.scientific.net/amr.821-822.1023.

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Relatively high molecular weight poly(glycolic acid)(PGA) was prepared by improved melting polycondensation of glycolic acid. Firstly, two kinds of catalyst, zinc acetate dihydrate and tin dichloride dehydrate, were utilized respectively, and a selection was made according to the molecular weight of final product. It has been found that the tin catalyst was the better one. Then the catalyst usage, the heating program, the polymerization time, as well as the vacuum condition were optimized. It was found that the high vacuum at 220~230°C contributed much to the molecular weight to the polymer, h

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27

Sokołowska, Martyna, Jagoda Nowak-Grzebyta, Ewa Stachowska, and Miroslawa El Fray. "Enzymatic Catalysis in Favor of Blocky Structure and Higher Crystallinity of Poly(Butylene Succinate)-Co-(Dilinoleic Succinate) (PBS-DLS) Copolymers of Variable Segmental Composition." Materials 15, no. 3 (2022): 1132. http://dx.doi.org/10.3390/ma15031132.

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To systematically investigate the synthesis of poly(butylene succinate)-co-(dilinoleic succinate) (PBS-DLS) copolymers and to enrich the library of polyesters synthesized via a sustainable route, we conducted a two-step polycondensation using fully biobased monomers such as diethyl succinate (DS), 1,4-butanediol (1,4-BD) and dilinoleic diol (DLD) in diphenyl ether, using Candida Antarctica lipase B (CAL-B) as biocatalyst. A series of PBS-DLS copolyesters with a 90-10, 70-30 and 50-50 wt% of hard (PBS) to soft (DLS) segments ratio were compared to their counterparts, which were synthesized usin

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28

Botvin, Vladimir, Svetlana Karaseva, Victor Khasanov, and Anatoly Filimoshkin. "Kinetic Study of Depolymerization of Lactic and Glycolic Acid Oligomers in the Presence of Oxide Catalysts." Polymers 12, no. 10 (2020): 2395. http://dx.doi.org/10.3390/polym12102395.

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For glycolic acid oligomers (GAO): l-lactic acid oligomers (LAO) mixtures, as an example, it was shown that the nature of the active sites of the catalysts significantly affect the depolymerization process. So, ZnO, which has mainly basic sites, leads to the highest yield of cyclic diesters. On the contrary, depolymerization in the presence of acidic γ-Al2O3 and without a catalyst is characterized by lower diester yields due to the prevalence of a side polycondensation reaction. Using GAO:LAO mixtures, it was shown that in the case of three studied systems (with ZnO, γ-Al2O3, and without catal

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29

Sha, Xu Zheng, and Ying Quan Zou. "The Synthesis of the Ether Compounds of Polycondensation Resin of the Pyrogallic Acid and the Divinylbenzene." Advanced Materials Research 380 (November 2011): 311–15. http://dx.doi.org/10.4028/www.scientific.net/amr.380.311.

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In order to better promote the localization of Positive CTP (Compute To Plate), based on the results of previous studies in our laboratory, synthesize an ether compounds of polycondensation resin of the pyrogallic acid and the divinylbenzene. The best conditions of the synthesis have been studied in the catalyst, solvent, reaction temperature, reaction time and molar ratio of reactants. The thermal CTP plate had been made by the new ether compounds of polycondensation resin of the pyrogallic acid and the divinylbenzene, it showed an excellent imaging performance.

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30

Hayashi, Shotaro, Yoshihisa Kojima та Toshio Koizumi. "Highly regioselective Pd/C-catalyzed direct arylation toward thiophene-based π-conjugated polymers". Polymer Chemistry 6, № 6 (2015): 881–85. http://dx.doi.org/10.1039/c4py01426j.

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Iliescu, Samaranda, Gheorghe Ilia, and Adriana Popa. "Phase transfer catalysis in the synthesis of phosphorus-containing polymers." Journal of the Serbian Chemical Society 70, no. 7 (2005): 951–56. http://dx.doi.org/10.2298/jsc0507951i.

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Polyphosphonates of high molecular weights were prepared from chloromethylphosphonic dichloride (CMPD) and 4,4?-sulfonyldiphenol (SDP) by two-phase interfacial polycondensation (l?l), in an organic solvent-aqueous alkaline solution system, with a phase-transfer catalyst, at ?8 ? ? 0 ?C. Alternative method, namely vapor-liquid interfacial polycondensation (v?l) of the same reagents gave better results (higher inherent viscosities and molecular weights). The polymers were characterized by spectroscopic techniques IR and 1H-NMR. The molecular weights and thermal stability determinations were carr

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32

Xie, Ziyi, Qingyun Wei, Tong Shan, Xiaoyang Zheng, Yi Zhang, and Hongliang Zhong. "Preparing polythiophene derivative with alternating alkyl and thioalkyl side chains via Kumada coupling for efficient organic solar cells." Polymer Chemistry 12, no. 44 (2021): 6456–64. http://dx.doi.org/10.1039/d1py01051d.

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A polythiophene, namely PTST with alternating alkyl and thioalkyl side chains, is prepared by Kumada catalyst-transfer polycondensation. PTST can hierarchically pre-aggregate in solution, and then form a favorable morphology in organic solar cells.

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33

Kobayashi, Saburo, Kaiyu Fujiwara, Dai-Hua Jiang, et al. "Suzuki–Miyaura catalyst-transfer polycondensation of triolborate-type fluorene monomer: toward rapid access to polyfluorene-containing block and graft copolymers from various macroinitiators." Polymer Chemistry 11, no. 42 (2020): 6832–39. http://dx.doi.org/10.1039/d0py01127d.

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We demonstrated that the Suzuki–Miyaura catalyst transfer polycondensation of a triolborate-type fluorene monomer can be an efficient and versatile approach to the synthesis of polyfluorenes (PFs) and PF-containing block and graft copolymers.

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34

Terzopoulou, Zoe, Elisavet Karakatsianopoulou, Nejib Kasmi, et al. "Effect of catalyst type on molecular weight increase and coloration of poly(ethylene furanoate) biobased polyester during melt polycondensation." Polymer Chemistry 8, no. 44 (2017): 6895–908. http://dx.doi.org/10.1039/c7py01171g.

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35

Awada, Hussein, Antoine Bousquet, Christine Dagron-Lartigau, and Laurent Billon. "Surface-initiated polymerization of A–A/B–B type conjugated monomers by palladium-catalyzed Stille polycondensation: towards low band gap polymer brushes." RSC Advances 5, no. 96 (2015): 78436–40. http://dx.doi.org/10.1039/c5ra08027d.

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A surface-initiated Stille polycondensation from Pd catalyst-immobilized ZnO nanorods affords well-defined core–shell nanoparticles. For the first time, a low band gap polymer was anchored on ZnO nanorods to create hybrid materials with tunable photophysical properties.

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36

Zarembo, V. I., S. A. Pankov, D. V. Zarembo, and V. Yu Sokolov. "The syntheses of poly (diethylene glycol adipate) in low-intensity ultrasound." Journal of Physics: Conference Series 2124, no. 1 (2021): 012008. http://dx.doi.org/10.1088/1742-6596/2124/1/012008.

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Abstract Poly (diethylene glycol adipate) is an important product of chemical technology. Several grades of polyesters (P-9, P-9A) are produced in the industry, in which poly(diethylene glycol adipate) is the main component. These composites are used in production of binders of mixed rocket solid fuels, as well as consumer goods. Poly(diethylene glycol adipate) is obtained by polycondensation of diethylene glycol and adipic acid. Usually, the polycondensation is carried out using catalysts. The use of catalysts complicates this process: requires further purification process or in solvent free

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37

Goto, Eisuke, Yuto Ochiai, Chen-Tsyr Lo, Tomoyuki Koganezawa, Mitsuru Ueda, and Tomoya Higashihara. "Synthesis of regioblock copolythiophene by Negishi catalyst-transfer polycondensation using tBu2Zn·2LiCl." Polymer Chemistry 8, no. 39 (2017): 6143–49. http://dx.doi.org/10.1039/c7py01416c.

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Regioblock copolythiohenes consisting of head-to-tail poly(3-hexylthiophene) (HT-P3HT) and head-to-head/tail-to-tail P3HT (HHTT-P3HT) segments could be synthesized by Negishi catalyst-transfer polycondensation (NCTP) using <sup>t</sup>Bu<sub>2</sub>Zn·2LiCl.

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Erdmann, T., J. Back, R. Tkachov, et al. "Dithienosilole-based all-conjugated block copolymers synthesized by a combination of quasi-living Kumada and Negishi catalyst-transfer polycondensations." Polym. Chem. 5, no. 18 (2014): 5383–90. http://dx.doi.org/10.1039/c4py00747f.

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The synthesis of diblock copolymers containing poly(dithieno[3,2-b:2’,3’-d]silole) and poly(3-hexylthiopnene) blocks was accomplished by a combination of quasi-living Kumada and Negishi catalyst-transfer polycondensations.

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Abbas, Mudassar, Julia Wappel, and Christian Slugovc. "Alternating Diene Metathesis Polycondensation (ALTMET) - Opitimizing Catalyst Loading." Macromolecular Symposia 311, no. 1 (2012): 122–25. http://dx.doi.org/10.1002/masy.201000095.

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Kiriy, Anton, Volodymyr Senkovskyy, and Michael Sommer. "Kumada Catalyst-Transfer Polycondensation: Mechanism, Opportunities, and Challenges." Macromolecular Rapid Communications 32, no. 19 (2011): 1503–17. http://dx.doi.org/10.1002/marc.201100316.

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Jabar, Ghulam, Muhammad Saeed, Sadaf Khoso, Anham Zafar, Javed Iqbal Saggu, and Amir Waseem. "Development of graphitic carbon nitride supported novel nanocomposites for green and efficient oxidative desulfurization of fuel oil." Nanomaterials and Nanotechnology 12 (January 2022): 184798042211063. http://dx.doi.org/10.1177/18479804221106321.

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The catalysts utilized for oxidative desulfurization have acquired significant attention and ability to improve the quality of the fuel oil by removing sulfur. In this work, the catalysts used for oxidative desulfurization include CoWO4 and Bi2WO6 with graphitic carbon nitride (g-C3N4) as support were synthesized by the one-pot hydrothermal method. Graphitic carbon nitride was obtained by thermal polycondensation of melamine at 550°C for 5 h. These catalysts were homogeneously dispersed on the surface of the support and their structure, morphology, and properties were determined by different c

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42

Apeksimov, N. V., and A. A. Sal'nikov. "Influence of introducing organic solvents of different nature on the gelation time of a binder based on methylphenyl organosilicon oligomer during curing." Plasticheskie massy, no. 9-10 (November 19, 2020): 31–34. http://dx.doi.org/10.35164/0554-2901-2020-9-10-31-34.

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The influence of the type of organic solvent, the acidity index, and the content of MF-12 methylphenyl organosilicon oligomer on the gelation time during polycondensation for the manufacture of heat-resistant electrical insulating materials is considered. The choice of the type of solvent that provides the best viscosity characteristics during impregnation and the greatest stability of the properties of the binder intended for use in combination with selective latent polycondensation catalysts, which exclude the effects of undesirable processes in the production and storage of pre-impregnated

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Sumera, Florentino C., Shienna Marie A. Pontillas, Josanelle Angela V. Bilo, and John Marty Mateo. "New Poly(Hydroxylauric-co-Lactic Acid) Liquid Polymer for Dissolving Lipophilic Drugs." KIMIKA 28, no. 1 (2017): 20–25. http://dx.doi.org/10.26534/kimika.v28i1.20-25.

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A liquid, biocompatible polyester based polymer, which could facilitate injectable formulations by simple mixing with the active substance (drug) is much needed by the pharmaceutical companies. A favourite candidate is polylactic acid (PLA) which is biocompatible and biodegradable. However PLA is solid with high crystallinity. Thus, in this research, hydroxylauric acid (HOLA) was copolymerized with lactic acid (LA) in different ratios by polycondensation technique at 180 °C, without a metal catalyst and avoiding the formation of interfering lactides, to provide a liquid polyester. The copolyme

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Theodorou, Alexis, Vasilios Raptis, Chrissie Isabella Maria Baltzaki, Thrassyvoulos Manios, Vagelis Harmandaris, and Kelly Velonia. "Synthesis and Modeling of Poly(L-lactic acid) via Polycondensation of L-Lactic Acid." Polymers 15, no. 23 (2023): 4569. http://dx.doi.org/10.3390/polym15234569.

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We present synthetic experiments of lactic acid (LA) polycondensation to produce poly(lactic acid) (PLA) as well as kinetic modeling calculations that capture the polymer molecular weight increase with time, given the initial concentrations. Tin-octoate-catalyzed polycondensation of (D,L)- or L-lactic acid was carried out in pre-dried toluene after azeotropic dehydration for 48–120 h at 130–137 °C. The polymerization was optimized by varying lactic acid and catalyst concentrations as well as the temperature. Gel permeation chromatography was used to experimentally follow the evolution of molec

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Zheng, Liuchun, Qiqi Xie, Guangjun Hu, et al. "Synthesis, Structure and Properties of Polyester Polyureas via a Non-Isocyanate Route with Good Combined Properties." Polymers 16, no. 7 (2024): 993. http://dx.doi.org/10.3390/polym16070993.

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Polyureas have been widely applied in many fields, such as coatings, fibers, foams and dielectric materials. Traditionally, polyureas are prepared from isocyanates, which are highly toxic and harmful to humans and the environment. Synthesis of polyureas via non-isocyanate routes is green, environmentally friendly and sustainable. However, the application of non-isocyanate polyureas is quite restrained due to their brittleness as the result of the lack of a soft segment in their molecular blocks. To address this issue, we have prepared polyester polyureas via an isocyanate-free route and introd

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Fu, Hao, Linbo Gong, and Shuling Gong. "A New Approach Utilizing Aza-Michael Addition for Hydrolysis-Resistance Non-Ionic Waterborne Polyester." Polymers 14, no. 13 (2022): 2655. http://dx.doi.org/10.3390/polym14132655.

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This work first synthesized a series of linear polyesters by step-growth polycondensation, then an amino-terminated hydrophilic polyether was grafted to the polyester as side-chains through aza-Michael addition to prepare a self-dispersible, non-ionic waterborne comb-like polyester (NWCPE). In contrast to traditional functionalization methods that usually require harsh reaction conditions and complex catalysts, the aza-Michael addition proceeds efficiently at room temperature without a catalyst. In this facile and mild way, the NWCPE samples with number-average molecular weight (Mn) of about 8

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Wan Daud, Wan Nasrin Afifa, Abdul Aziz Ishak, Syafiza Abd Hashib, and Miradatul Najwa Mohd Rodhi. "Chemical Compound Evaluation of Polylactic Acid from L(+)-Lactic Acid Monomer Obtained through Cassava Fermentation by Rhizopus oryzae." Advanced Materials Research 1113 (July 2015): 523–27. http://dx.doi.org/10.4028/www.scientific.net/amr.1113.523.

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In this study, L(+)-lactic acid (LLA) from cassava fermentation by Rhizopusoryzae NRRL 395 was used as monomer in polymerization through direct polycondensation reaction. HPLC analysis of the fermented product was carried out to confirm the presence of LLA, through the matching of retention time compared to the standard of LLA. The chemical compound in poly (L-lactic acid), PLLA was evaluated after polymerization through direct polycondensation of LLA at 180°C, with the presence of tin (II) 2-ethylhexanoate as catalyst. Fourier Transform Infrared Spectrometry (FTIR) was used to characterize th

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Zhang, Ping, Lin Bo Wu, and Bo Geng Li. "Synthesis of Aromatic Polyesters with Pendent Carboxyl Groups from Diphenolic Acid, Bisphenol a and Isophthaloyl Chloride by Interfacial Polycondensation." Advanced Materials Research 239-242 (May 2011): 2616–19. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.2616.

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Aromatic polyesters bearing pendent carboxyl functionalities were prepared by interfacial polycondensation of diphenolic acid, bisphenol A and isophthaloyl chloride with tetrabutylammonium chloride as phase transfer catalyst. The copolyester composition was confirmed with HPLC analysis. The polymerization process and composition of the copolyesters were examined by considering influences of reaction temperatures, time, ratio of feeds, agitation speeds.

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Grisorio, Roberto, and Gian Paolo Suranna. "Intramolecular catalyst transfer polymerisation of conjugated monomers: from lessons learned to future challenges." Polymer Chemistry 6, no. 45 (2015): 7781–95. http://dx.doi.org/10.1039/c5py01042j.

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Eleven years after the first reports on intramolecular catalyst transfer polycondensations, this review aims to critically recap on the fundamental “lessons” that can be learned from the historic literature as well as from the fervid activity that has emerged in the last three years.

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Yu, Feng, Joice Thomas, Mario Smet, Wim Dehaen, and Bert F. Sels. "Molecular design of sulfonated hyperbranched poly(arylene oxindole)s for efficient cellulose conversion to levulinic acid." Green Chemistry 18, no. 6 (2016): 1694–705. http://dx.doi.org/10.1039/c5gc01971k.

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This contribution is about various sulfonated hyperbranched poly(arylene oxindole)s (SHPAOs) preparedviaa convenient A<sub>2</sub>+ B<sub>3</sub>polycondensation and subsequent sulfonation as water-soluble and recyclable acid catalysts for the conversion of cellulose to levulinic acid (LA).

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