甲基丙烯酸三丁基锡酯与甲基丙烯酸甲酯共聚合竞聚率的测定和计算

采用红外光谱分析共聚物组成的方法，测定了不同温度下甲基丙烯酸三了基锡酯（ＴｈＴＭ）和甲基丙烯酸甲酯（ＭＭＡ）在甲苯溶液中的自由基共聚合竞聚率．并用Ｆ—Ｒ法、Ｍ—Ｌ法和ＥＶＭ法处理了实验结果，讨论了不同的数据处理的方法对共聚合竞聚率数值的合理性和准确性的影响．随聚合温度的升高，ＴＢＴＭ和ＭＭＡ逐渐倾向于理想共聚合．由共聚温度与ｒ１和Ｒ２的关系得到各温度下最为合理的ｒ１和ｒ２值，并讨论了聚合温度对共聚活性的影响．     

气相色谱法测定共聚合竞聚率的研究

以苯乙烯和甲基丙烯酸正丁酯共体系为例，在共聚单体敏感点组成附近做重复实验，进行了４０、６０、８０、１００、１２０℃下的低转化率的共聚合，用气相色谱测定共聚物的组成，用Ｍａｙｏ－Ｌｅｗｉｓ微分组成方程的误差变量法计算竞聚率，同时给出竞聚率的９５％可信椭圆区间。通过与ＦＴＩＲ、ＮＭＲ方法的比较，对气相色谱法测定竞聚率的准确性进行了讨论。     

苯乙烯和丙烯酸丁酯自由基共聚合竞聚率测定与研究

苯乙烯和丙烯酸丁酯自由基共聚合竞聚率测定与研究吴平平，吴玉芳，杨全兴，韩哲文朱清仁（华东理工大学高分子材料研究所，上海，２００２３７）（中国科技大学结构分析开放实验室）关键词苯乙烯，丙烯酸丁酯，竞聚率，序列分布苯乙烯和丙烯酸丁酯是重要的共聚合体系。然...     

丙烯酰胺与4-乙烯基吡啶共聚合反应竞聚率

测定了丙烯酰胺与4－乙烯基吡啶共聚反应的竞聚率。用紫外分光光度法测定了不同浓度的4－乙烯基吡啶均聚物的吸光度，从而求出在低转化率不同初始单体组成的共聚物中4－乙烯基吡啶含量。用FR和KT两种作图法及YBR计算法对单体的竞聚率进行计算和比较。结果表明：KT法和YBR法计算法较为准确，4－乙烯基吡啶的竞聚率和丙烯酰胺的竞聚率分别为γrVP=0.636,γAM=0.379。     

13C-NMR研究丁二烯-异戊二烯共聚合的竞聚率和共聚物的序列分布

 用¹³C-NMR方法研完了不同配料比的丁二烯-异戊二烯本体共聚和溶液共聚物的结构,定量计算出了共聚物二元组的浓度和数均序列长度,采用T(?)DO″S法计算出了本体共聚和溶液共聚的竞聚率,并证明各种共聚产物的序列分布都服从一级Markov统计模型。     

N－烯丙基咔唑与甲基丙烯酸甲酯高温共聚合

Ｎ－烯丙基咔唑不能均聚合，但可与甲基丙烯酸甲酯在高温下共聚合。测定了２００—２６０℃时两单体共聚合竞聚率，１度为２５０℃时，ｒ１和ｒ２均小于１。共聚物分子量随着共聚温度升高而降低．结果表明，共聚体系中，增长反应与降解反应同时存在．该反应可能是自由基过程．     

核磁共振法测定自由基共聚合竞聚率综合实验的设计

利用核磁共振法（NMR）测定苯乙烯和甲基丙烯酸甲酯自由基共聚合的竞聚率,并通过凝胶渗透色谱（GPC）和差示扫描量热仪（DSC）表征聚合物的相对分子质量及相对分子质量分布和玻璃化转变温度,以验证所得产物为共聚物而非2种均聚物的共混物。本实验内容丰富,综合性强,在全面培养学生实验技能的同时也能提高学生的研究能力。     

甲基丙烯酸甲酯-苯乙烯自由基共聚合微型化研究

采用甲基丙烯酸甲酯-苯乙烯自由基共聚合微型化实验,研究了微型化实验条件下,聚合反应工艺条件对共聚产物性能及转化率的影响,说明了高分子微型化实验的可行性。同时,通过微型实验与常规实验相比,进一步阐述微型高分子化学实验不仅装置精巧、新颖,还有利于减少火灾、爆炸等事故的发生几率,而且原料用量及废液量大幅减少,具有节约和环保的双重意义。微型化学实验由于简化了实验装置和实验操作,将其用在教学或科研上,比起常规实验更加简单易行、安全可靠。     

甲基丙烯酸三丁基锡酯共聚甲基丙烯酸甲酯的竞聚率测定方法准确性探讨

甲基丙烯酸三丁基锡酯共聚甲基丙烯酸甲酯的竞聚率测定方法准确性探讨赵秉熙陈文明陈道勇阎立峰（中国科学技术大学应用化学系合肥２３００２６）朱清仁（中国科学院结构成分开放实验室合肥２３００２６）韩哲文陆志豹（华东理工大学材料科学系上海２００２３７）关键词...     

聚氧乙烯大单体与甲基丙烯酸甲酯的共聚合及其共聚物的研究

研究了聚氧乙烯（ＰＥＯ）大单体与甲基丙烯酸甲酯的溶液共聚合，考察了引发剂用量，单体总浓度、投料比、反应时间对共聚物组成和分子量的，ＩＲ、ＨＮＭＲ、ＧＰＣ、ＶＰＯ、ＤＳＣ航透射电等测定结果表明，经纯化的共聚物具有预期的结构，且呈现微相分离，体外人体正常抗凝血浆复钙时间测定结果显示：共聚物的抗凝血明显好于玻璃和ＰＭＭＡ均聚物，且随共聚物中ＰＥＯ含量的增加而增强，经水化处理的共聚物的抗凝血性比未经处理的     

CPE—g—MMA共聚物（MC）的合成

MC是以氢化聚乙烯（CPE）为母体，甲基丙烯酸甲酯（MMA）为支链的接校共聚物．由于MC主链为饱和链，与MBS（聚了二烯-g-MMA-苯乙烯接技共聚物）相比在耐老化性等方面有较大的改进．由于聚甲基丙烯酸甲酯（PMMA）与聚氯乙烯（PVC）具有较好的相容性，并对PVC有增初作用，因此MC不仅可作为PVC的增韧剂，还可作为PVC-CPE体系的增容剂．很大程度改善了PVC与CPE间的相容性，使产物的机械性能大幅度提高，并大大降低增韧剂用量[1]．MC的合成方法有多种[1.2]．我们采用自由基型水相悬浮聚合体系合成法．考察了反应时间、反应温度…     

在聚合物微球 GMA/MMA 表面同步合成与固载卟啉及固载化金属卟啉的催化氧化性能

 制备了甲基丙烯酸缩水甘油酯 (GMA) 与甲基丙烯酸甲酯 (MMA) 共聚微球 GMA/MMA, 并通过键合有对羟基苯甲醛 (HBA) 的改性微球 HBA-GMA/MMA 与苯甲醛 (或取代苯甲醛) 以及吡咯间的 Adler 反应, 实现了卟啉在共聚微球 GMA/MMA 表面的同步合成与固载, 制得了固载有苯基卟啉 (PP)、对氯苯基卟啉 (CPP)、对硝基苯基卟啉 (NPP) 的功能化微球 PP-GMA/MMA, CPP-GMA/MMA 和 NPP-GMA/MMA. 重点考察了影响卟啉同步合成与固载过程的因素. 制备了固载有钴卟啉的催化剂, 并以分子氧氧化乙苯为模型反应, 考察了催化剂的活性. 结果表明, 苯甲醛取代基的结构、催化剂的酸性和溶剂的极性对卟啉的同步合成与固载都有较大的影响; 钴卟啉催化剂对分子氧氧化乙苯反应具有较高的催化活性, 且当钴卟啉外环上含有强吸电子基团硝基时, 催化剂活性最高.     

Copolymerization of N‐vinylcaprolactam and glycidyl methacrylate: Reactivity ratio and composition control

Free‐radical copolymerizations of N‐vinylcaprolactam (VCL) and glycidyl methacrylate (GMA) were investigated to synthesize temperature‐responsive reactive copolymers with minimized compositional heterogeneity. The average copolymer composition was determined by Fourier transform infrared and nuclear magnetic resonance techniques. The reactivity ratios for VCL and GMA were found to be 0.0365 ± 0.0009 and 6.44 ± 0.36 by the Fineman–Ross method and 0.039 ± 0.006 and 6.75 ± 0.29 by the Kelen–Tudos method, respectively. When prepared by batch polymerization, VCL–GMA copolymers had a highly heterogeneous composition and fractions of different solubilities in water. The use of a gradual feeding technique, which included the sequential addition of more reactive GMA monomer into the reaction, yielded copolymers with much more homogeneous composition. The produced copolymers with 0.9 and 0.11 fractional GMA contents preserved their temperature‐responsive properties and precipitated from aqueous solutions when the temperature exceeded 31 °C. The GMA units in the VCL–GMA copolymers were capable of reacting with amino end‐functionalized poly(ethylene oxide) at room temperature to produce poly(N‐vinylcaprolactam)–poly(ethylene oxide) graft copolymers. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 183–191, 2006     

Bulk Free‐Radical Copolymerization of n‐Butyl Acrylate and n‐Butyl Methacrylate: Reactivity Ratio Estimation

The reactivity ratios for the bulk free‐radical copolymerization of n‐butyl acrylate (BA)/n‐butyl methacrylate (BMA) are estimated at 80 °C. By performing a series of low conversion runs including replicate runs, the reactivity ratios are estimated as r_BA = 0.460 and r_BMA = 2.008. Runs to high conversions are then conducted at three different feed compositions (f_BMA = 0.2, 0.5, and 0.8) to validate the reactivity ratios. The composition data from the high conversion experiments show good agreement with the estimated reactivity ratios in the integrated form of the Mayo–Lewis model. The molecular weight, gel content, and glass transition temperature of BA/BMA copolymers are also determined.

     

Bulk Copolymerization of Conjugated Linoleic Acid With Styrene and Butyl Acrylate: Reactivity Ratio Estimation

Free radical bulk copolymerizations of conjugated linoleic acid (CLA)/styrene (Sty) and CLA/butyl acrylate (BA) were performed at 80°C. Copolymers were characterized for composition, conversion, molecular weights and glass transition temperature (T_g). A pseudo-kinetic model was developed and validated with experimental data. Reactivity ratios estimations were performed and one impurity commonly found in CLA, oleic acid, influenced the reaction kinetics significantly. The T_g of CLA homopolymer was predicted to be 5°C.     

Synthesis and Characterization of Novel Methacrylic Copolymers: Determination of Monomer Reactivity Ratios

A new methacrylic monomer, 4‐nitro‐3‐methylphenyl methacrylate (NMPM) was prepared by reacting 4‐nitro‐3‐methyl phenol dissolved in methyl ethyl ketone (MEK) in the presence of triethylamine as a catalyst. Copolymerization of NMPM with methyl methacrylate (MMA) has been carried out in methyl ethyl ketone (MEK) by free radical solution polymerization at 70±1°C utilizing benzoyl peroxide (BPO) as initiator. Poly (NMPM‐co‐MMA) copolymers were characterized by FT‐IR, ¹H‐NMR and ¹³C‐NMR spectroscopy. The molecular weights (M_w and M_n) and polydispersity indices (M_w/M_n) of the polymers were determined using a gel permeation chromatograph. The glass transition temperatures (T_g) of the copolymers were determined by a differential scanning calorimeter, showing that T_g increases with MMA content in the copolymer. Thermogravimetric analysis of the polymers, performed under nitrogen, shows that the stability of the copolymer increases with an increase in NMPM content. The solubility of the polymers was tested in various polar and non‐polar solvents. Copolymer compositions were determined by ¹H‐NMR spectroscopy by comparing the integral peak heights of well separated aromatic and aliphatic proton peaks. The monomer reactivity ratios were determined by the Fineman‐Ross (r₁ =7.090:r₂=0.854), Kelen‐Tudos (r₁=7.693: r₂=0.852) and extended Kelen‐Tudos methods (r₁=7.550: r₂= 0.856).     

2-甲基-2-丁烯二酸单甲酯的合成及其与丙烯腈二元共聚的表观竞聚率的测定

以柠糠酸酐为原料, 合成了一种可以与丙烯腈(AN, acrylonitrile)共聚的新单体: 2-甲基-2-丁烯二酸单甲酯(MBAME). 以偶氮二异丁腈(AIBN, 2,2’-azobis isobutyronitrile)为引发剂, 70 ℃下引发MBAME与AN在N,N-二甲基甲酰胺(DMF, N,N-dimethylformamide)中进行无规共聚, 通过Fineman-Ross法测定了两者在DMF溶液聚合体系的表观竞聚率, γ1(AN)＝7.985, γ2(MBAME)＝0.599, 有助于优化聚丙烯腈基碳纤维用树脂的生产工艺.     

丙烯酸甲酯和甲基丙烯酸酯基团转移无规共聚的竞聚率

丙烯酸甲酯和甲基丙烯酸酯基团转移无规共聚的竞聚率⒇邹友思林东海张景辉潘容华（厦门大学化工系，厦门大学核磁共振实验室，厦门，３６１００５）单体竞聚率作为一个定量数据，对于不同投料比下共聚物组成的预计和控制，共聚反应动力学和机理研究均有重要作用。丙烯酸...     

乙丙共聚物熔融接枝甲基丙烯酸环氧丙酯

乙丙共聚物熔融接枝甲基丙烯酸环氧丙酯张晓民，尹志辉，殷敬华（中国科学院长春应用化学研究所高分子物理开放实验室长春１３００２２）关键词乙丙共聚物，甲基丙烯酸环氧丙酯，接枝共聚接枝共聚物可作为不相容共混体系的增容剂［１，２］，反应加工法制备乙丙共聚物（Ｅ...