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Jiraya Kiriratnikom Xun Zhang Xiaohan Cao Bo Chu Chengjian Zhang Xinghong Zhang 《Journal of polymer science. Part A, Polymer chemistry》2022,60(15):2262-2268
Facile construction of sulfur-rich polymers using readily available raw chemicals is an area aggressively pursued but challenging. Herein we use common feedstocks of ethylene oxide (EO), propylene oxide (PO), and carbonyl sulfide (COS) to synthesize copoly(thioether)s which are traditionally produced from unpleasant and difficult to store episulfides. In this protocol, the EO/COS coupling selectively generates a pure poly(ethylene sulfide) (PES) with melting temperature (Tm) values up to 172°C and high yields up to 98%. The EO/PO/COS terpolymerization leads to the incorporation of soft poly(propylene sulfide) (PPS) and hard PES segments together, affording a random PES-co-PPS copoly(thioether) with the complete consumption of EO and PO. Additionally, by simply varying the EO/PO feeding ratio, the obtained copoly(thioether)s possess tunable thermal properties, Tm values in the range of 76–144°C, and excellent solubility. These copolymerizations are conducted in one-pot/one-step at industrially favored reaction temperatures of 100–120°C using catalysts of common organic bases, suggesting a facile and practical manner. Especially, the copoly(thioether) exhibits high refractive indices up to 1.68 owing to its high sulfur content, suggesting a broad application prospect in optical materials. 相似文献
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Siriwan Praban Supajittra Yimthachote Jiraya Kiriratnikom Sucheewin Chotchatchawankul Jonggol Tantirungrotechai Khamphee Phomphrai 《Journal of polymer science. Part A, Polymer chemistry》2019,57(20):2104-2112
A series of tin(II) complexes supported by N2O2 bis(phenol)‐amine ligands were prepared from the reactions of the corresponding ligands with Sn[N(SiMe3)2]2 in benzene at room temperature. The ligands were designed to have different substituted group at the ortho‐position on the aryl rings (R = tBu, CH3) and N‐containing side arm (E = ? CH2NEt2 and pyridine) giving a variation of tin(II) complexes (R = tBu, E = CH2NEt2, 2a ; R = tBu, E = py, 2b ; R = CH3, E = CH2NEt2, 2c ; R = CH3, E = py, 2d ). All complexes were characterized by NMR spectroscopy and single‐crystal X‐ray analysis. The single‐crystal X‐ray crystallography revealed that all complexes have a monomeric four‐coordinate tin center with a distorted seesaw structure. All complexes are active for solvent‐free polymerization of l ‐lactide at 120 °C giving poly(l ‐lactide) with narrow to moderate dispersity (Ð = 1.12–1.56). In the presence of benzyl alcohol during the polymerization, the resulting polymer was found to be linear having benzyl alcohol as the end group while, in the absence of benzyl alcohol, the polymer was cyclic. The large tBu group at the ortho‐position was found to decrease polymerization activity while the more basic ? CH2NEt2 group was found to increase the polymerization activity. The polymerization of rac‐lactide under a similar condition gave PLA having a slight heterotactic bias for all catalysts. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019, 57, 2104–2112 相似文献
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