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COPOLYMERIZATION AND DETERMINATION OF MONOMER reactivity ratios OF DL-LACTIDE WITH 3-BENZYLOXYMETHYL-1,4-DIOXANE-2,5-DIONE

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Chinese Journal of Polymer Science 2002年第5期20卷 413-417页

作者： Ji-yuan Yang Jian Yu Mei Li Zhong-wei Gu Xin-de Feng Department of Polymer Science and Engineering Peking University Beijing 100871, China National Research Institute for Family Planning Beijing 100081, China Peking Univ Dept Polymer Sci & Engn Beijing 100871 Peoples R China Natl Res Inst Family Planning Beijing 100081 Peoples R China

The copolymerization of DL-LA and 3-BMG was carried out in bulk with stannous 2-ethythexanoate as the catalyst. A series of copolymers with pendant protected groups were obtained and characterized by H-1-NMR and GPC analysis. The monomer reactivity ratios were evaluated by the Fineman-Ross method and the Kelen-Tudos method and found to be r(BMG)=1.96 and r(LA)=0.37, respectively.

关键词： 3-benzyloxymethyl 1,4-dioxane-2,5-dione DL-lactide reactivity ratios

ANTIMICROBIAL ACTIVITY OF COPOLYMERS OF 2,4-DICHLOROPHENYL ACRYLATE WITH STYRENE:SYNTHESIS,CHARACTERIZATION AND reactivity ratios

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Chinese Journal of Polymer Science 2009年第1期27卷 121-130页

作者： Hetal J.Patel Mitesh G.Patel Kirit H.Patel Arabinda K.Ray Rajni M.Patel Department of Chemistry Sardar Patel UniversityVallabh Vidyanagar-388120GujaratIndia

Some copolymers of 2,4-dichlorophenyl acrylate (2,4-DCPA) with styrene (St) of different teed compositions were prepared by tree radical polymerization technique using 2,2′-azobisisobutyronitrile (AIBN) as an initiator,and the copolymers were characterized by IR *** copolymer composition obtained by UV-spectra led to determination of reactivity ratio by employing Fineman-Ross (F-R) and Kelen-Tudos (K-T) *** molecular weight,as well as intrinsic viscosity,was obtained by vapor pressu...

关键词： Copolymers reactivity ratios Vapor pressure osmometry Thermal analysis Antimicrobial screening

Monomer reactivity ratios for fluoroacrylate and butyl methacrylate in miniemulsion copolymerizations initiated by potassium persulphate

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Chinese Chemical Letters 2009年第4期20卷 478-482页

作者： Qing Hua Zhang Zhen Huan Luo Xiao Li Zhan Feng Qiu Chen College of Materials Science and Chemical Engineering Zhejiang University Hangzhou 310027 China

Miniemulsion copolymerization of butyl mathacrylate （BMA） with fluoroacrylate （HFMA, TFMA） was carried out at 70 ℃ by employing potassium persulphate （KPS） as initiator. Copolymer compositions at low conversion levels were determined by ^1H NMR spectra techniques. The reactivity ratios were evaluated by employing Kellen-Tudos （K-T） methods, which yields the apparent reactivity ratios, rBMA = 0.74, rHFMA = 0.87 and rBMA = 0.73, rTFMA = 0.75, respectively, and Q- and e-values of HFMA and TFMA were calculated by the Alfrey-Price method. The results show that HFMA and TFMA are more active than BMA, and the cross-propagation rate constant is greater than the self-propagation one in these two copolymerizations.

关键词： Fluoroacrylate reactivity ratios Miniemulsion Copolymerization

MONOMER reactivity RATIO AND THERMAL PERFORMANCE OFα-METHYL STYRENE AND GLYCIDYL METHACRYLATE COPOLYMERS

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Chinese Journal of Polymer Science 2010年第3期28卷 323-330页

作者：梁淑君 Taiyuan Institute of Technology State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology College of Materials Science and Engineering Beijing University of Chemical Technology

Synthesis and characterization of the copolymers （PAG） of α-methyl styrene （AMS） and glycidyl methacrylate （GMA） are presented. The copolymers of PAG were characterized by gel permeation chromatography （GPC）, Fourier transform infrared spectroscopy （FTIR）, nuclear magnetic resonance （^1H-NMR） and thermogravimetery （TG）. Based on the copolymer compositions determined by ^1H-NMR, the reactivity ratios of AMS and GMA were found to be 0.105 ± 0.012 and 0.883 ± 0.046 respectively by Kelen-Tudos method. TG revealed that thermal stability of the copolymers decreased with increasing the AMS content in the copolymers, which indicated that the degradation was mainly caused by the chain scission of AMS-containing structures. Under heating, the copolymers depolymerize at their weak bonds and form chain radicals, which could further initiate other chemical reactions.

关键词： Copolymerization α-Methyl styrene Glycidyl methacrylate reactivity ratios Depolymerization