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乙丙共聚物熔融接枝甲基丙烯酸环氧丙酯 总被引:2,自引:0,他引:2
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... 相似文献
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甲基丙烯酸甲酯和长链烷基酯的嵌段共聚戴李宗*邹友思郭金泉潘容华(厦门大学化学系厦门361005)关键词阴离子聚合,甲基丙烯酸酯,嵌段共聚合,表征1996-08-07收稿,1996-11-18修回国家自然科学基金资助项目嵌段共聚合能得到具微相体系的共聚... 相似文献
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甲基丙烯酸丁酯和苯乙烯的原子转移自由基共聚 总被引:2,自引:0,他引:2
研究了甲基丙烯酸丁酯和苯乙烯两种不同极性单体的原子转移自由基嵌段共聚和无规共聚,得到了实测分子量与理论分子量相近、分子量分布较窄的嵌段共聚物和无规共聚物。聚合过程中分子量和单体转化率成比例增加,多分散性指数变化不大。用^1H NMR法测定共聚组成,Kdisplay status 相似文献
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青霉素酰化酶在甲基丙烯酸缩水甘油酯共聚物上的固定化 总被引:6,自引:0,他引:6
用共价键合法将青霉素酰化酶固定化在珠状多孔的甲基丙烯酸缩水甘油酯(GM)共聚物上,研究了固定化反应时间、温度、pH值和酶液用量对固定化青霉素酰化酶的表观活性、表观偶联效率、活性回收及稳定性的影响.将GM共聚物载体加入到磷酸缓冲液(0.1mol/L,pH10.8)与青霉素酰化酶液(每克干载体用酶液1ml)的混合溶液中,在30℃下反应72h,单位质量(干重)固定化酶的表观活性为348U/g,表观偶联效率为66.7%,活性回收为31.7%. 相似文献
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室温下以膦腈碱(t-Bu P4)为催化剂,催化甲基丙烯酸烯丙酯(AMA)和甲基丙烯酸甲酯(MMA)进行负离子共聚反应.用核磁(1H-NMR、13C-NMR)、红外光谱(FTIR)、凝胶渗透色谱(GPC)、示差扫描量热仪(DSC)和热失重分析仪(TGA)等对聚合物结构和性能进行表征.结果发现,t-Bu P4能在室温下成功催化AMA与MMA的共聚反应,一步法合成结构可控的含悬垂双键共聚物.共聚反应中单体AMA和MMA的转化率均高于90%,且无交联或凝胶生成.通过NMR和FTIR对聚合物进行结构分析表明,AMA单体仅甲基丙烯酸酯双键参与聚合反应,烯丙基双键不参与聚合反应、无交联反应、环化反应等.聚合物中烯丙基结构单元的含量可通过体系中AMA/MMA的投料比调节.GPC结果表明所得共聚物分子量可控且分子量分布较窄.TGA和DSC结果表明,共聚物的热分解温度升高,玻璃化温度降低. 相似文献
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活性聚合以其无链转移、无链终止和引发速度远大于增长速率的特点,应用于合成单分散聚合物、预定序列结构的嵌段共聚物等.常用的活性聚合方法如阴离子聚合、阳离子聚合及基团转移聚合对反应条件要求苛刻,不能用于丙烯酸酯类极性单体和苯乙烯类非极性单体的嵌段共聚.与... 相似文献
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Reactivity ratios and full conversion range data (conversion, copolymer composition, molecular weight averages, glass transition temperature) are presented for styrene (STY)/methyl methacrylate (MMA)/copolymerization at elevated temperatures (130 and 150°C), a region where polymerization studies are scarce for the system, both for purely thermal polymerization and for peroxide‐initiated ones. 相似文献
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在四氢呋喃(THF)与环己烷的混合溶剂中,以正丁基锂(n-BuLi)为引发剂,采用具有较大空间位阻和特定电荷环境的P配合物为添加剂,实现了异戊二烯(Ip)和甲基丙烯酸甲酯(MMA)的阴离子嵌段共聚。分别采用GPC、^1H—NMR对聚合物的结构进行了分析表征。结果表明:随着THF与环己烷体积比的增大,单体的转化率呈现下降的趋势;同时空间位阻较大的P配合物的加入,堵塞了正、负离子对之间的部分通道,有效地抑制了MMA段聚合副反应的发生,在易于工业化的0℃之下成功合成了分子量分布窄(1.21)的聚异戊二烯一聚甲基丙烯酸甲酯嵌段共聚物(PI—b—PMMA),并且共聚物中PI嵌段以3,4结构链节为主。 相似文献
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High temperature starved feed semibatch solution polymerization is used to produce acrylic resins for automotive coatings. These operating conditions promote secondary reactions that have a strong impact on polymerization rate and polymer molecular weight (MW). This study experimentally investigates high temperature semibatch copolymerization of butyl methacrylate and styrene, a system subject to the combined effect of depropagation and penultimate propagation kinetics. A mechanistic model including these complexities is constructed in Predic®. With the termination rate coefficient fit to the semibatch results and all other coefficients taken from independent experiments, the model provides good predictions of monomer conversion and MW. Various representations of copolymer termination kinetics from the literature are compared to the values fit from experiment. 相似文献
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Summary: High temperature semibatch free radical copolymerizations of dodecyl methacrylate (DMA) and styrene (ST) were carried out. A mechanistic model including depropagation and penultimate chain growth was built in Predici®. The comparison between the simulated and the experimental final polymer molecular weights indicates that the initiator efficiency decreases when DMA is used as a comonomer. Using estimated initiator efficiencies and termination coefficients, the model provides good fits to the complete set of experimental data. 相似文献
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W. Carl McIntosh Evemarie Hamann Ronald Oertel Michael Bartke 《Macromolecular Symposia》2007,259(1):102-109
Summary : The application of the terminal copolymerization model to polar modified anionic initiated 1,3-butadiene/styrene systems in hydrocarbon solvent requires the determination of twelve kinetic model parameters. These include frequency factors (kxY,∞), activation energies (ExY) and live chain end association numbers (nxY) for all four possible combinations of live chain end termini and free monomer. The individual determination of all twelve parameters requires an enormous numerical effort and a large number of experiments. A method for estimating parameters with a minimum number of kinetic batch experiments in an industrial environment will be demonstrated. 相似文献
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《Macromolecular rapid communications》2017,38(15)
Herein, a novel photoinitiated polymerization‐induced self‐assembly formulation via photoinitiated reversible addition–fragmentation chain transfer dispersion polymerization of glycidyl methacrylate (PGMA) in ethanol–water at room temperature is reported. It is demonstrated that conducting polymerization‐induced self‐assembly (PISA) at low temperatures is crucial for obtaining colloidal stable PGMA‐based diblock copolymer nano‐objects. Good control is maintained during the photo‐PISA process with a high rate of polymerization. The polymerization can be switched between “ON” and “OFF” in response to visible light. A phase diagram is constructed by varying monomer concentration and degree of polymerization. The PGMA‐based diblock copolymer nano‐objects can be further cross‐linked by using a bifunctional primary amine reagent. Finally, silver nanoparticles are loaded within cross‐linked vesicles via in situ reduction, exhibiting good catalytic properties.
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有机锡聚合物兼具杀菌防腐的生物活性功能和一般高分子材料的结构功能,有着潜在的应用前景[1]。本工作应用X射线萤光光谱测定甲基丙烯酸三丁基锡(TBTM)和甲基丙烯酸异戊酯(IPMA)共聚物中锡的含量。方便,迅速地获得了该共聚物的组成,计算了TBTM和IPMA在四氢呋喃中,55℃下共聚合的竞聚率,其结果分别为0.29和0.24。 相似文献
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苯乙烯-甲基丙烯酸甲酯嵌段共聚物的合成与表征 总被引:2,自引:0,他引:2
采用阴离子聚合技术合成了一系列苯乙烯-甲基丙烯酸甲酯的两嵌段共聚物(PS-b-PMMA).采用GPC、FTIR、NMR(1HNMR、13CNMR和固体NMR)和DMA等手段进行了表征.结果表明,所得产物为高分子量、窄分布、具有微相分离结构的两嵌段共聚物. 相似文献
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Carboxymethyl chitosan grafted with glycidyl methacrylate was synthesized by the reaction of carboxymethyl chitosan (CSCM) which was prepared from chitosan first and glycidyl methacrylate. The product has been characterized by Fourier transform infrared spectrum (FT-IR), X-ray diffraction (XRD), proton nuclear magnetic resonance (1H-NMR), solid 13carbon nuclear magnetic resonance (Solid 13C-NMR), 13carbon nuclear magnetic resonance (13C-NMR), and chemical analysis, which had different thermal properties from chitosan. 相似文献