双组分Iniferter引发苯乙烯聚合的研究

研究了由N,N-二乙基二硫代氨基甲酸苄酯(BDC)与四甲基秋兰姆化二硫(TMTD)组成的复合Iniferter(引发剂-转移-终止剂)引发苯乙烯的光聚合反应。     

MMA的原子转移自由基聚合新体系

以α－溴异丁酸乙酯为引发剂，研究了不同体系的甲基丙烯酸甲酯的原子自由基聚合，考察了配位剂及溶剂对聚合的影响。并且采用新的聚合体系，以溴异丁酸乙酯／CuBr/CuBr2/NNN为引发体系，二苯醚为溶剂，成功地实现MMA的ATRP。     

40℃下EPN—Br／CuCl／bpy引发MMA的原子转移自由基聚合

以α－溴代丙酸乙酯（ＥＰＮ－Ｂｒ）为引发剂,氯化亚铜（ＣｕＣｌ）为催化剂,联二吡啶（ｂｐｙ）为配位剂,乙腈或丙酮为溶剂,在低温（４０℃）下引发甲基丙烯酸甲酯（ＭＭＡ）的原子转移自由基聚合。动力学和相对分子质量研究表明,该反应是一可控聚合过程。在丙酮溶剂中,聚合反应有一明显的诱导期。     

自引发纯丙烯酸酯的合成及光聚合性质研究

合成了一种全新的自引发纯丙烯酸酯,利用实时红外光谱技术研究了自引发感光高分子的光聚合过程,比较了不同引发剂浓度下的聚合速率和转化率;结果表明,引入到高分子侧链的自由基引发剂仍具有较高的引发活性,双键基团也具有很好的光聚合反应活性。     

光聚合现状与展望

本文叙述了自由基和阳离子聚合光引发剂体系的最新进展,并且提供了不同引发模式下在所有光引发体系中有关引发效率、波长限制和环境安全问题的解决办法。在过去10年里,通过光聚合制备了复杂或纳米结构的大分子,因此本文也介绍了光聚合在生物材料、表面改性和纳米复合材料领域的新兴应用。     

含端基氯低聚物引发剂的合成及其引发苯乙烯聚合的研究

通过对４种端羟基低聚物进行氯乙酰化反应,制备了一系列含端基氯的低聚物,然后以这些含端基氯的低聚物为大分子引发剂,在ＣｕＣｌ／ｂｐｙ存在下引发苯乙烯的ＡＴＲＰ反应,得到ＡＢＡ嵌段共聚物。用＾１Ｈ－ＮＭＲ分析证明了聚合物的嵌段结构,以ＳＥＣ测定了聚合物的相对分子质量及其分布,发现嵌段聚合物的相对分子质量和单体转化率成正比,并和相对分子质量的理论值Ｍ↑－ｎ,ｔｈ＝（Δ［Ｍ］／［ｏｌｉｇｏｍｅｒ－Ｃｌ］）     

姜黄素衍生物为引发剂引发MMA的ATRP聚合的研究

将姜黄素与2-溴异丁酰溴(EBi B-Br)通过酰基化反应引入溴原子制备含溴姜黄素衍生物(Br-Curcumin-Br),然后再以Br-Curcumin-Br为引发剂、Cu Br/Bpy(2,2’-联吡啶)为催化剂引发甲基丙烯酸甲酯(MMA)进行原子转移自由基聚合。考察了此聚合反应过程中MMA的转化率以及聚合物分子量随时间的关系,分子量及分子量分布随转化率的关系。研究结果表明:聚合物转化率和分子量都随时间增加呈线性增加,分子量随MMA转化率增加也呈线性增加,而且不同聚合物的分子量分布比较窄(PDI<2)。     

自由基型光聚合引发剂的最新发展

系统地介绍了近几年来，自由基型光聚合引发剂的发展概况。主要包括水溶型、高子分型、双分子型、双分子型以及其他新型光聚合引发剂体系的结构类型、光引发机理、适用的光谱范围。     

Synthesis of Triblock Copolymers via Photopolymerization of Styrene and Methyl Methacrylate Using Macrophotoinitiators Possessing Poly(ethylene glycol) Units

Macrophotoinitiators based on poly(ethylene glycol)s bearing benzyl tereftalmono amid moieties were synthesized by the reaction of poly(ethylene glycol) (PEG) terminated with terephtaloyl chloride and benzyl amine. The initiators possessing PEG with different molecular weights were used in the photoinduced radical polymerization of styrene (S) and methyl methacrylate (MMA) to yield poly(styrene-b-ethylene glycol-b-styrene) and poly(methyl methacrylate-ethylene glycol-b-methyl methacrylate) triblock copolymers. Characterization of macrophotoinitiators were performed by elemental anlysis, IR and ¹H-NMR spectrum. The elemental analysis results agreed with the theoretical values. The IR and ¹H-NMR spectra showed that the poly(ethylene glycol) units were reacting with the tereftloyl chloride and benzylamine. Characterization of the block copolymers was carried out by spectral measurements, GPC and fractional precipitation methods. The polydispersities of the block copolymers were observed between 1.2–2.32 for poly(methyl methacrylate-ethylene glycol-b-methyl methacrylate) and 1.25–1.90 for poly(styrene-b-ethylene glycol-b-styrene) from GPC measurements.     

Study on the Copolymerization Kinetics of 8-Quinolinyl Methacrylate with Methyl Methacrylate,n-Butyl Methacrylate and Styrene

Abstract

The 8-quinolinyl methacrylate (8-QMA) monomer was prepared and characterized by the conventional methods of analysis. The 8-QMA monomer was copolymerized with methyl methacrylate (MMA), n-butyl methacrylate (BMA) and styrene under different monomer feed ratio using azobisisobutyronitrilic (AIBN) as an initiator by solution copolymerization. The polymerization reaction was allowed to proceed only upto sim; 10%. The composition of the resulting copolymers was determined by UV-visible spectrophotometry and reactivity ratio for each monomer pair was calculated. The relative reactivity of the monomers was discussed on the basis of the size of alkyl group in methacrylates and effect of resonance on the stability of the styryl radicals during the copolymerization.     

悬浮聚合法合成甲基丙烯酸甲酯-苯乙烯共聚物的研究

采用无机/有机三元复合分散体系进行了甲基丙烯酸甲酯与苯乙烯悬浮聚合的研究,对影响共聚物珠粒形成的因素进行了考察,得到了合成甲基丙烯酸甲酯-苯乙烯共聚物的工艺条件.用傅立叶变换红外光谱(FT-IR)方法表征了珠状共聚物的结构,并用热分析仪考察了共聚物的热性能.结果表明,在以有机蒙脱土为分散荆的优化工艺条件下,合成的甲基丙烯酸甲酯-苯乙烯共聚物的热性能有明显提高.     

Synthesis and Characterization of Homo- and Copolymers of N-4-Azodiphenyl Maleimide with Methyl Methacrylate and Styrene

The synthesis and free radical homopolymerization of N-4-azodiphenylmaleimide (ADPMI) and copolymerization of methyl methacrylate (MMA) and styrene (ST) with ADPMI using an AIBN initiator were performed in THF solvent at 70°C. A series of copolymers, ADPMI-MMA and ADPMI-ST, were prepared using different feed ratios of comonomers. The polymer samples have been characterized by solubility tests, intrinsic viscosity measurements, FT-IR, ¹H-NMR spectral analysis, and thermo-gravimetric analysis. The values of monomer reactivity ratios r₁ and r₂ determined by Fineman-Ross and Kelen-Tudos methods are 0.16 and 0.63, and 0.26 and 0.25 in ADPMI/MMA and ADPMI/ST systems, respectively. Alfrey-Price Q-e values for ADPMI are Q = 2.27 and e = 1.92, and 0.41 and 1.949 for ADPMI/MMA and ADPMI/ST systems, respectively. It was found that the initial and final decomposition temperatures increased with the increase of ADPMI content in the copolymer samples.     

Copolymerization of 2-(4-tert-butylphenoxy)-2-oxo-ethyl Methacrylate with Methyl Methacrylate and Styrene: Synthesis, Characterization, and Monomer Reactivity Ratios

A tertierbutylphenoxy group containing methacrylate based monomer 2-(4-tert-butylphenoxy)-2-oxo-ethyl methacrylate (TBPOEMA) was synthesized by reacting 4-tertierbutylphenyl chloroacetate (TBPClAcO) with sodium methacrylate in acetonitrile. TBPClAcO was prepared by reacting tertierbutylphenol dissolved in benzene with chloroacetylchloride. The free-radical-initiated copolymerization of TBPOEMA, with methyl methacrylate (MMA) and styrene (ST) was carried out in dimethylsulphoxide (DMSO) solution at 65°C using 2,2-azobisisobutyronitrile (AIBN) as an initiator with different monomer-to-monomer ratios in the feed. The monomer TBPOEMA and copolymers were characterized by FTIR, ¹H- and ¹³C-NMR spectral studies. The copolymer composition obtained from the ¹H-NMR spectra led to the determination of reactivity ratios. The reactivity ratios of the monomers were determined by the application of Finemann–Ross and Kelen–Tüdös linear methods and the Behnken nonlinear least-squares method. The analysis of reactivity ratios revealed that MMA and ST are more reactive than TBPOEMA, and copolymers formed are statistical in nature. The molecular weights _w and _n) and polydispersity index of the polymers were determined using gel permation chromagtography. Thermogravimetric analysis of the polymers reveal that the thermal stability of the copolymers increases with an increase in the mole fraction of TBPOEMA in the copolymers. Glass transition temperatures of the copolymers were found to decrease with an increase in the mole fraction of TBPOEMA in the copolymers. The apparent thermal decomposition activation energies (E _d) were calculated by Ozawa method using the SETARAM Labsys TGA thermobalance.     

甲基丙烯酸甲酯合成及生产

介绍了甲基丙烯酸甲酯7种生产方法,其中异丁烯氧化法被认为是最具有竞争力工艺之一。对我国有工业意义的技术路线为：可以发挥石油裂解C4馏分的资源优势,选择异丁烯氧化法工艺路线。该路线不使用硫酸和剧毒品氢氰酸,废液少,环境安全容易控制,可以连续化生产。     

甲基丙烯酸甲酯合成工艺的研究

甲基丙烯酸甲酯(MMA)是合成有机玻璃及MBS树脂的单体。文章通过合成离子液体N-甲基-2-吡咯烷酮硫酸氢盐([Hnmp]HSO4)作为催化剂,催化合成甲基丙烯酸甲酯。研究不同的反应温度、不同的反应时间、不同的醇酸比、不同的阻聚剂用量对反应的影响。     

甲基丙烯酸甲酯和苯乙烯在离子液体中的自由基聚合

甲基丙烯酸甲酯和苯乙烯经4,4’-偶氮-双(4-氰基戊酸)引发,分别在离子液体([C4mim][PF6])和苯中进行了自由基聚合反应,比较了相同引发剂和单体投料比下,2种介质体系中的聚合速率、相对分子质量和分子量分布,得出2种单体在[C4mim][PF6]中的聚合速率、相对分子质量明显高于苯中的产物,且[C4mim][PF6]经多次重复使用,均能得到性能稳定的聚合产物。     

Free Radical Copolymerization of Methyl Methacrylate and Styrene with N-(4-Carboxyphenyl)maleimide

The free radical copolymerization of methyl methacrylate (MMA) or styrene (St) with N-(4-carboxyphenyl)maleimide (CPMI) was carried with AIBN as an initiator in THF solvent at 80°C. A series of copolymers of MMA and St with CPMI were prepared using different feed ratios of comonomers. The values of monomer reactivity ratios (r₁, r₂) determined by Fineman-Ross and Kelen-Tudos methods are 0.26 and 2.51 in the CPMI/MMA system and 0.08 and 0.22 in the CPMI/St system. Alfrey–Price Q-e values for CPMI were calculated as Q = 1.05 and e = 0.41 in the CPMI/MMA system and Q = 1.21 and e = 0.91 in the CPMI/St system. The polymer samples have been characterized by solubility tests, intrinsic viscosity measurements, FT-IR and ¹H-NMR spectral analysis, and thermo-gravimetric analysis. It was found that the initial and final decomposition temperatures increased with increasing the amount of CPMI in the copolymer. The integral procedural decomposition temperature and energy of activation of thermal degradation have also been reported.     

新型共聚物催化合成肉桂酸苄酯的研究

采用新型磺化聚苯乙烯-co-甲基丙烯酸丁酯P(St-co-BMA)共聚物首次用于肉桂酸苄酯的催化合成研究。P(St-co-BMA)对肉桂酸苄酯的合成反应具有较好的催化活性。当n(肉桂酸):n(苄醇)=1．0:3．0,反应温度120℃, 反应时间4 h,催化剂用量为肉桂酸质量的5％,酯收率大于96％。该催化剂具有较高的催化活性,易于回收,可重复使用五次以上。催化剂可用稀硫酸再生,多次使用过的催化剂经再生后的催化活性与新制备的共聚物催化剂的催化活性相比几乎没有差别。