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Synthesis and bulk polymerization kinetics of monomer dehydroabietic acid-(2-acryloyloxy-ethoxy)-ethyl ester

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Frontiers of Agricultural Science and Engineering 2017年第1期4卷 97-105页

作者： Haibo ZHANG Yanping YANG He LIU Jie SONG Shibin SHANG Zhanqian SONG National Engineering Laboratory for Biomass Chemical Utilization Key and Open Laboratory of Forest Chemical Engineering State Forestry Administration Key Laboratory of Biomass Energy and Material Institute of Chemical Industry of Forest ProductsChinese Academy of Forestry Department of Chemistry and Biochemistry University of Michigan-Flint Institute of New Technology of Forestry Chinese Academy of Forestry

A bulk polymerization monomer dehydroabietic acid-(2-acryloyloxy-ethoxy)-ethyl ester(DHADG-AC) was synthesized from dehydroabietic acid(DHA). The chemical structure of DHA-DG-AC was characterized by1~HNMR,(13)~CNMR, MS and FT-IR. The kinetics of the bulk polymerization of DHA-DG-AC was investigated by Differential Scanning Calorimeter(DSC).Two kinds of kinetic model(nth-order model and autocatalytic model) were used to investigate the polymerization process. The results showed that the experim e nt al DSC c u r ve s w e r e c o n si st e nt wi th t he computational data generated by the autocatalytic kinetic model, and the value of E_a was 95.73 k J·mol^(–1).

关键词： dehydroabietic acid bulk polymerization kinetics autocatalytic kinetic model

Copolymerization of α-Methylstyrene and Styrene

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Chinese Journal of Polymer Science 2014年第8期32卷 986-995页

作者： Qian Liu Lian-ying Liu 马育红 Chang-wen Zhao 杨万泰 College of Material Science and Engineering Beijing University of Chemical Technology State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology

In this paper, the effects of temperature from 60 ℃ to 80 ℃ and the molar ratios in monomer feed on the copolymerization of α-methylstyrene （AMS） and styrene （St） were studied. The resulting copolymers, designated as PAS, were characterized by FTIR, GPC, NMR and TGA. When the reaction temperature was below 75 ℃, the molecular weights increased almost linearly as the evolution of the copolymerization. The phenomenon revealed that AMS could mediate the conventional free radical polymerization having some features of a controlled system. As the AMS/St = 50/50 （molar） in feed, the overall fraction of the AMS unit incorporated into the copolymer was as high as 42 mol%, the monomer conversion could be more than 90 wt% and the molecular weights could reach as high as 4400. However, since the styrene is more reactive than AMS, the AMS fraction in copolymer increased with the overall monomer conversion. The 13C-NMR revealed the products were random copolymers which had triads, such as -AMS-AMS-AMS-, -St-AMS-AMS- （-AMS-AMS-St-） and -St-AMS-St-. TGA curves demonstrated that the degradation temperature of the resulting copolymers went down from about 356.9 ℃ （0 mol% AMS） to 250.2 ℃ （42 tool% AMS）. This behavior demonstrated that there exist weak bonds in the AMS- containing sequences which could be used as potential free radical generators.

关键词： α-Methylstyrene Styrene bulk polymerization Thermal decomposition.

“LIVING”/CONTROLLED RADICAL polymerization OF ETHYL METHYLACRYLATE WITH 2,2’-AZOBISISOBUTYRONITRILE/FERRIC CHLORIDE/TRIPHENYLPHOSPHINE INITIATION SYSTEM

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Chinese Journal of Polymer Science 2000年第2期18卷 149-153页

作者： Xiao-ping Chen Kun-yuan Qiu Department of Polymer Science and Engineering, College of Chemistry, Peking University, Beijing 100871, China Peking Univ Coll Chem Dept Polymer Sci & Engn Beijing 100871 Peoples R China

'Living'/controlled radical polymerization of ethyl methacrylate (EMA) was carried out with a 2,2'-azobisisobutyronitrile (AIBN)/ferric chloride (FeCl_3)/triphenylphosphine (PPh_3) initiation system at 85℃. Thc numberaverage molecular weight (M_n) increases linearly with monomer conversion and the rate of polymerization is first order withrespect to monomer concentration. The M_w of PEMA ranges from 3900 to 17600 and the polydispersity indices are quitenarrow (1.09～1.22). The conversion can reach up to～100% and M_w of the polymers obtained is close to that designed. Thepolymerization mechanism belongs to the reverse atom transfer radical polymerization (ATRP). The polymer was end-functionalized by chlorine atom, which acts as a macroinitiator to proceed extension polymerization in the presence ofCuBr/bipy catalyst system via an ATRP process. The presence of ω-chlorine in the PEMA obtained was identified by ~1H-NMR spectrum.

关键词： 'Living'/controlled radical polymerization Reverse ATRP Ethyl methacrylate AIBN/FeCl_3/PPh_3 bulk polymerization

Preparation,Characterization and Service Performance of Fatty Acid/PMMA Shape-Stabilized Phase Change Material

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Journal of Donghua University(English Edition) 2011年第1期28卷 10-14页

作者：孟多王立久 Department of Civil Engineering Liaoning University of Technology Department of Civil and Hydraulic Engineering Dalian University of Technology

A series of fatty acid/poly methyl methacrylate(PMMA) shape-stabilized phase change materials(PCMs) have been prepared by bulk polymerization *** the composite,fatty acid(capric acid,stearic acid,and their eutectic mixture) acts as core material and PMMA serves as matrix,which coats the fatty acid to prevent the leakage of melted fatty *** prepared shape-stabilized PCMs were characterized on the morphology,phase change behavior,chemical characterization and thermal *** results indicate that the composites with proper phase change temperature and latent heat are able to keep solid morphology in macro level during thermal storage *** cycling test also indicates that the composite PCMs have good thermal ***,thermal conductivity and thermal performance are investigated and the results show that the shape-stabilized PCMs have the higher thermal conductivity than fatty acid and exhibited good thermal performance in controlling the atmosphere temperature.

关键词： shape-stabilized phase change material fatty acid poly methyl methacrylate(PMMA) bulk polymerization

Thermal Stability and Crystallinity Study of Polystyrene/SiO₂ Nano-Composites Synthesis via Microwave-Assisted In Situ polymerization

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Open Journal of Synthesis Theory and Applications 2016年第2期5卷 15-23页

作者： Nikesh Samarth Linchon Mehta Vinayak Kamble Malhari Kulkarni Prakash Mahanwar Department of Polymer and Surface Engineering Nathalal Parekh Marg Mumbai India Polymer Engineering Maharashtra Institute of Technology Pune India

Serials of polystyrene/SiO2 Nano composites (PS/SiO2) with different content of inorganic fillers were successfully prepared by the in situ bulk radical polymerization of styrene under microwave irradiation. The effect of the amount of Nano SiO2 on the properties of the PS/SiO2 Nanocomposites along with the average relative molecular masses (Mn, Mz and Mw) was investigated by thermal analysis and X-Ray Diffraction (XRD). Their structural model was proposed on the basis of the Optical Microscopy, FTIR (Fourier Transform Infrared) analysis, differential scanning calorimetry (DSC), gel permeation chromatography (GPC) and X-Ray Diffraction (XRD). The dispersion of nanoparticles in Polystyrene is observed in the magnified image. The effect of microwave irradiation power on molecular weight of polystyrene was also studied. It was found that, the microwave assisted reaction needs less time as compare to conventional polymerization and found to be in between 10 to 15 min.

关键词： Nanocomposites In Situ polymerization bulk polymerization Nano SiO2

Synthesis of high molecular weight polylactic acid from aqueous lactic acid co-catalyzed by tin(II)chloride dihydrate and succinic anhydride

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Science Bulletin 2005年第20期 136-138页

作者： LEI Ziqiang, BAI Yanbin & WANG Shoufeng Key Laboratory of Polymer Materials of Gansu Province, College of Chemistry and Chemical Engineering, Northwest Normal University, Lanzhou 730070, China

Polylactic acid was synthesized from commer- cial available cheap aqueous lactic acid (85%―90% w/w) using succinic anhydride and SnCl2·2H2O as catalyst in the absence of organic solvents. As a result, polylactic acid with a molecular weight of 60000 was prepared in 10 h. The new procedure is much simple, cheap and outstanding in that the start material is aqueous lactic acid; the catalytic system is environmentally benign.

关键词： polylactic acid bulk polymerization catalytic polymeri- zation.

Comparison of molecularly imprinted bulk polymer and nanospheres for diethylstilbestrol

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Comparison of molecularly imprinted bulk polymer and nanosph...