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Controlled Drug Release Studies of Atenolol Using Differently Sulfonated Acryloxyacetophenone and methyl methacrylate Copolymer Resins as Drug Carriers

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Chinese Journal of Polymer Science 2014年第3期32卷 280-291页

作者： K.Doraswamy P.Venkata Ramana Department of Chemistry Sri Krishnadevaraya University

2-Acryloxyacetophenone （AAP） was prepared and subjected to suspension polymerization with methyl methacrylate （MMA） using azobisisobutyronitrile （AIBN） as free radical initiator. The differently sulfonated AAP-MMA cross-linked copolymer cationic exchange resins were prepared by sulfonation with concentrated sulphuric acid at 70 ~C. Several characteristics of the prepared resins were evaluated, i.e. FTIR, the ion-exchange capacity （IEC）, thermo gravimetric analysis （TGA）, particle size distribution and microscopic morphology. The resin characteristics were altered with degree of sulfonation, providing that differently sulfonated resins could be prepared. The behavior of atenolol （ATL） loading and in vitro release in the USP stimulated gastric and intestinal fluids of the obtained resins were evaluated. The drug loaded in the resin increased with increasing degree of sulfonation and hence the drug binding site in resin employed. The drug release was lower from the resins with higher content of sulfonic group due to the increase in the diffusive path depth. The drug release was a little lower in stimulated gastric fluid （SGF） than in stimulated intestinal fluids （SIF）. The basic groups, ionized to a little greater extent in SGF and preferred binding with the resin rather than releasing. Hence, the differently sulfonated resins could be utilized as novel carriers for drug delivery.

关键词： 2-Acryloxyacetophenone methyl methacrylate Different sulfonation Cationic exchange resins Atenolol In vitro drug release.

DESIGN AND SYNTHESIS OF NOVEL CHIRAL IONIC LIQUIDS AND THEIR APPLICATION IN FREE RADICAL POLYMERIZATION OF methyl methacrylate

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Chinese Journal of Polymer Science 2003年第3期21卷 265-270页

作者：宛新华 Department of Polymer Science & Engineering College of Chemistry & Molecular Engineering.Peking University Beijing 100871 China

Two new chiral ionic liquids, 1 -((-)-menthoxycarbonylmethylene)-3-methylimidazolium hexafluorophosphateand 1-((-)-menthoxycarbonylmethylene)-3-hexadecylimidazolium hexafluorophosphate, were designed an d prepared. Theirchemical structures were characterized by ~1H-NMR. Reverse atom transfer radical polymerization of methyl methacrylate(MMA) in these two ionic liquids was carried out using AIBN/CuCl_2/bipy as the initiating system. The resultant well-definedpolymethyl methacrylate (PMMA) was employed as a macroinitiator to induce the atom transfer radical polymerization ofmenthyl methacrylate (MnMA) in chlorobenzene, which yielded a PMMA-b-PMnMA diblock copolymer with narrow polydispersity.

关键词： Chiral ionic liquids Reverse ATRP Free radical polymerization methyl methacrylate Menthyl methacrylate

SYNTHESIS OF POLY(methyl methacrylate)-graft-POLYSTYRENE BY ATOM TRANSFER RADICAL POLYMERIZATION

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Chinese Journal of Polymer Science 2003年第4期21卷 427-432页

作者：付志峰 Key Laboratory for Controlled Chemical Reactions of Education Ministry Beijing University of Chemical Technology Beijing 100029 China

The radical copolymerization of methyl methacrylate and 2-hydroxyethyl methacrylate was carried out via atomtransfer radical polymerization (ATRP) initiated by ethyl 2-bromoisobutyrate and catalyzed by CuBr/2,2'-bipyridinecomplex. This polymerization proceeds in a living fashion with controlled molecular weight and low polydispersity. Theobtained copolymer was esterified with 2-bromoisobutylryl bromide yielding a macroinitiator, poly(methyl methacrylate-co-2-hydroxyethyl methacrylate-co-2-(2-bromoisobutyryloxy)ethyl methacrylate), and its structure was characterized by ~1H-NMR. This macroinitiator was used for ATRP of styrene to synthesize poly(methyl methacrylate)-graft-polystyrene. Themolecular weight of graft copolymer increased with the monomer conversion, and the polydispersity remained relatively *** individual grafted polystyrene chains were cleaved from the macroinitiator backbone by hydrolysis and the hydrolyzed product was characterized by ~1H-NMR and GPC.

关键词： Atom transfer radical polymerization Graft copolymer Styrene methyl methacrylate

Ambient Temperature Living Radical Copolymerization of Styrene and methyl methacrylate with Sodium Hypophosphite as Reducing Agent

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Chinese Journal of Polymer Science 2015年第2期33卷 362-370页

作者：刘晓辉 Hui-na Li Fei-jun Zhang Shan Xie Zhan-jun Liu 李彦国 School of Materials Science and Engineering Tianjin Key Laboratory of Fiber Modification and Functional FiberTianjin Polytechnic University College of Pharmacy Hebei United University State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied ChemistryChinese Academy of Sciences

A facile, safe and economical reducing agent, sodium hypophosphite（Na H2PO2·H2O）, has been successfully employed for ambient temperature living radical copolymerization of styrene（St） and methyl methacrylate（MMA）. Such effective reducing agent significantly improved the reactivity of low reactive St monomers during the copolymerization, where the reactivity ratios of St and MMA were determined to be 0.50 and 0.36 by Finemann-Ross method. Thus the copolymerizations proceeded fast and showed typical living/controlled features, as evidenced by pseudo first-order kinetics of polymerization, linear increase in molecular weight versus monomer conversion, and low polydispersity index values. Effects of the concentration of reducing agent and the monomer feed ratio on the copolymerization were investigated in detail. Furthermore, gel permeation chromatography and 1H-NMR analyses as well as chain extension experiments confirmed the high chain-end functionality of the resultant copolymer.

关键词： Controlled/living radical copolymerization Sodium hypophosphite Ambient temperature methyl methacrylate Styrene

Microemulsion Polymerization of methyl methacrylate

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Chemical Research in Chinese Universities 2001年第3期17卷 325-330页

作者： DAN Yi YANG Yun-hua CHEN San-yu State Key Laboratory of Polymer Materials Engineering Department of Polymer Materials Science and EngineeringSichuan UniversityChengdu 610065P.R.China

The microemulsion polymerization of methyl methacrylate was studied. The effects of feeding modes on the structure and the properties of the obtained polymer microlatex were investigated by measuring the conversion, the transmittance and the refractive index of the latex, and by measuring the particle size, the molecular weight and the glass transition temperature (T_g) of the polymers. The results show that compared to the batch feeding mode, the semi-continuous feeding mode is more favorable to form a PMMA microlatex with a higher transmittance, a smaller particle size, a higher molecular weight and a higher T_g. And the obtained PMMA microlatex has a 30%—40% (mass fraction) polymer content, a 0. 03 emulsifier/water weight ratio, a 0. 05 emulsifier/monomer weight ratio and a 17 nm average particle diameter, which is very important for the industrialization of the microemulsion polymerization technique.

关键词： Microemulsion polymerization methyl methacrylate Fedding mode Particle size

EFFECT OF TEMPERATURE ON COPOLYMERIZATION PARAMETERS OF HYDROXYETHYL ACRYLATE AND methyl methacrylate

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Chinese Journal of Polymer Science 1998年第1期16卷 25-31页

作者：李欣欣印啸敏吴平平韩哲文朱清仁 Department of Polymers East China University of Science and Technology Shanghai 200237 China Structure Research Laboratory University of Science and Technology of China Hefei 230026 China

The copolymerization of 2-hydroxyethyl acrylate (HEA, M//1) and methyl methacrylate (MMA, M//2) in cyclohexanone was studied. The multiple experiments of solution copolymerization with low conversion were carried out at two sensitive composition feed points at 60, 80, 100, 120 and 140 degree C, respectively. The composition of the copolymers was analyzed by **1H-NMR. The reactivity ratios which were estimated by the Error-in-Variable Method (EVM) of Mayo-Lewis equation were found to be r//1 equals 0.328, r//2 equals 1.781 for 60 degree C; 0.375, 1.709 for 80 degree C; 0.406, 1.654 for 100 degree C; 0.439, 1.540 for 120 degree C and 0.455, 1.400 for 140 degree C, and the 95% joint confidence intervals of the reactivity ratios were also determined. According to r//1 and r//2, Arrhenius relations and the activity energy difference between the homo- and cross-propagation were calculated. (Author abstract) 12 Refs.

关键词： reactivity ratio 2-Hydroxyethyl acrylate methyl methacrylate copolymerization copolymer composition

Polymerization of methyl methacrylate catalyzed by mono-/bis-salicylaldiminato nickel(Ⅱ) complexes and methylaluminoxane

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Frontiers of Chemical Science and Engineering 2011年第1期5卷 19-25页

作者： Jihong LU Danfeng ZHANG Qian CHEN Buwei YU School of Materials Science and Engineering East China University of Science and TechnologyShanghai 200237China Daqing Petrochemical Research Center of CNPC Daqing 163714China

Two types of salicylaldiminato-based nickel complexes,mono-ligated Ni(II)complexes([O-C_(6)H_(4)-o-C(H)=N-Ar]Ni(PPh_(3))(Ph)(5),[O-(3,5-Br_(2))C_(6)H_(2)-o-C(H)=N-Ar]Ni(PPh_(3))(Ph)(6),[O-(3-t-Bu)C_(6)H_(3)-o-C(H)=N-Ar]Ni(PPh_(3))(Ph)(7))and bis-ligated Ni(II)complexes([O-(3,5-Br_(2))C_(6)H_(2)-o-C(H)=N-Ar]_(2)Ni(8),[O-(3,5-Br_(2))C_(6)H_(2)-o-C(H)=N-2-C_(6)H_(4)(PhO)]_(2)Ni(9),Ar=2,6-C_(6)H_(3)(i-Pr)_(2))were synthesized and characterized by Fourier transform infrared spectroscopy(FT-IR),nuclear magnetic resonance(NMR),mass spectrography(MS)and elemental analysis(EA).In the presence of methylaluminoxane(MAO)as cocatalyst,all the nickel complexes exhibited high activities for the polymerization of methyl methacrylate(MMA)and syndiotactic-rich poly(methyl methacrylate)(PMMA)was *** complexes with less bulky substituents on salicylaldiminato framework possessed higher activities,while with the same salicylaldiminato,the mono-ligated nickel complexes showed higher catalytic activity than bis-ligated ones.

关键词： late transition metal catalyst methyl methacrylate polymerization salicylaldiminato nickel complexes methylaluminoxane syndiotactic structure

Copolymerization of Dimethylaminoethyl methacrylate and methyl methacrylate Catalyzed by Substituted Indanyl Lanthanide(Ⅱ) Complexes

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Journal of Rare Earths 2005年第S1期23卷 92-96页

作者：齐民华沈琪陈小平 Institute of Chemical Engineering Maoming College Maoming 525000 ChinaDepartment of Chemistry and Chemical Engineering Suzhou University Suzhou 215006 China Department of Chemistry and Chemical Engineering Suzhou University Suzhou 215006 China Institute of Chemical Engineering Maoming College Maoming 525000 China

The substituted indenyl lanthanide(Ⅱ) complexes as single component catalyzed for the copolymerization of dimethylaminoethyl methacrylate and methyl methacrylate were studied. The results indicate that these complexes all show good catalytic activity and the catalytic activity is affected by the temperature and time of polymerization, amount of catalyast and the solvent as well. The yields of the copolymerization are not affected by the ratio of monomers at all. In order of catalytic activity of the substituted indenyl lanthanide(Ⅱ) complexes: (C_5H_9C_9H_6)_2Sm(THF)>(C_2H_5C_9H_6)_2Sm(THF)_2>(C_5H_9C_9H_6)_2Yb(THF)_2>KSm(C_5H_9C_9H_6)_3(THF)_3>(PhCH_2C_9H_6)_2Sm(THF)_2. The reactivity ratio of the copolymerization of dimethylaminoethyl methacrylate and methyl methacrylate catalyzed by the substituted indenyl lanthanide (Ⅱ) complex (C_5H_9C_9H_6)_2Yb(THF)_2 (r_1=0.98, r_2=0.71) were measured.

关键词： substituted indenyl lanthanide complexes methyl methacrylate dimethylaminoethyl methacrylate copolymerization

KINETICS OF SUSPENDED EMULSION POLYMERIZATION OF methyl methacrylate

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Chinese Journal of Polymer Science 2004年第6期22卷 543-548页

作者：包永忠 Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China

The kinetics of suspended emulsion polymerization of methyl methacrylate (MMA), in which water acted as the dispersed phase and the mixture of NMA and cyclohexane as the continuous phase, was investigated. It showed that the initial polymerization rate (R-p0) and steady-state polymerization rate (R-p) were proportional to the mass ratio between water and oil phase, and increased as the polymerization temperature, the potassium persulphate concentration ([I]) and the Tween20 emulsifier concentration ([S]) increased. The relationships between the polymerization rate and [I] and [S] were obtained as follows: R-p0 proportional to [I](0.73)[S](0.32) and R-p proportional to [I](0.71)[S](0.23). The above exponents were close to those obtained from normal MMA emulsion polymerization. It also showed that the average molecular weight of the resulting poly(methyl methacrylate) decreased as the polymerization temperature, [I] and [S] increased. Thus, MMA suspended emulsion polymerization could be considered as a combination of many miniature emulsion polymerizations proceeding in water drops and obeyed the classical kinetics of MMA emulsion polymerization.

关键词： suspended emulsion polymerization methyl methacrylate polymerization rate average molecular weight and molecular weight distribution