共查询到17条相似文献,搜索用时 93 毫秒
1.
2.
种子溶胀悬浮聚合法制备分子印迹聚合物微球 总被引:15,自引:1,他引:15
以酪氨酸为印迹分子 ,甲基丙烯酸为功能单体 ,三羟甲基丙烷三甲基丙烯酸酯 (TRIM )为交联剂 ,采用种子溶胀悬浮聚合法在水溶液中制备了一系列分子印迹聚合物微球 (MIPMs)。利用扫描电镜 (SEM)对此微球的粒径大小、粒径分布、表面孔与孔径分布等进行了分析研究 ,探讨了影响其形貌的主要因素 ,并将所得微球用作固定相研究了其分子选择吸附性能。研究表明 ,种子溶胀悬浮聚合法能够制得单分散性较好的、表面带有微孔的分子印迹聚合物微球 ,且该微球呈现出较好的特异吸附性能。 相似文献
3.
4.
5.
6.
美托洛尔球形分子烙印聚合物的制备及吸附性能考察 总被引:1,自引:0,他引:1
以聚苯乙烯乳液为种球,以药品美托洛尔为模板分子,甲基丙烯酸为功能单体,二甲基丙烯酸乙二醇酯为交联剂,采用两步溶胀和种子悬浮聚合方法,通过优化反应条件,制得单分散性优良的球形分子烙印聚合物(molecularly imprinted polymers,MIPs)。重点讨论了致孔剂、分散剂和乳化剂的选择、搅拌速度对聚合物的粒径大小和分布、表观形态及吸附性能等的影响。通过聚合物对几种β-受体类药物分子的平衡吸附实验表明,MIP对模板分子美托洛尔具有良好的识别能力。 相似文献
7.
苯乙烯微乳液种子聚合 总被引:20,自引:1,他引:20
通过观测苯乙烯微乳液种子聚合前后体系内聚合物粒子大小及其分布的变化发现,无论是γ射线还是KPS引发,聚合过程中都没有新的聚合物粒子生成。尽管聚合前体系中存在单体溶胀的胶束,但在聚合过程中这些胶束主要充当单体仓库,自己成核聚合的几率很低。由于微乳液种子聚合体系内,单体量相对较低,聚合物粒子数目很大,其聚合动力学明显不同于常规乳液种子聚合。 相似文献
8.
以玉米淀粉和丙烯酸为主要原料,过硫酸铵为引发剂,N,N-亚甲基双丙烯酰胺为交联剂,采用新型两步水溶液聚合法合成聚丙烯酸/玉米淀粉半互穿网络水凝胶,并对凝胶的结构和研究淀粉的用量、pH值对水凝胶溶胀性能的影响。研究表明:水凝胶具优越的溶胀性、pH敏感性和膨胀可逆性,使其可以应用于很多领域。 相似文献
9.
种子溶胀法制备单分散高交联聚苯乙烯微球 总被引:2,自引:0,他引:2
以分散聚合法制得平均粒径为1.80μm的聚苯乙烯微球为种子,与溶胀剂和单体、交联剂的混合物经二步溶胀聚合法,制备了单分散高交联聚苯乙烯微球。讨论了单体浓度和醇水比对种球的影响,以及溶胀剂的种类、溶胀剂浓度、交联剂浓度、溶胀温度和搅拌速度等因素对交联聚苯乙烯微球粒径及分散系数的影响。用扫描电子显微镜、离心式粒度分析仪及DSC分析测试技术对微球的外观形貌、粒径大小及分布和玻璃化转变温度分别进行了表征。结果表明,当溶胀剂质量分数为25%、交联剂质量分数为23%、溶胀温度30℃、搅拌速度为150r/min时,可制得平均粒径为6.20μm且单分散性较好的高交联聚苯乙烯微球。 相似文献
10.
11.
12.
无皂种子分散聚合法制备单分散双重响应性微凝胶 总被引:1,自引:0,他引:1
以N-异丙基丙烯酰胺及2-乙烯基吡啶为主要单体, 采用无皂种子分散聚合法制备了单分散的、具有温度及pH双重响应性能的核-壳结构微凝胶, 并以扫描电镜及动态激光光散射等手段对微凝胶粒子的结构和性能进行了研究. 溶胀行为研究表明, 微凝胶粒子具有独立的互不干扰的温度及pH敏感性能, 其体积相变温度与纯聚N-异丙基丙烯酰胺(PNIPAM)凝胶基本一致, 说明局部分布的弱电离单体不会对PNIPAM凝胶的体积相变温度造成影响. 相似文献
13.
Dr. Soichiro Ogi Natsumi Fukaya Dr. Arifin Bastian Bjerkem Skjelstad Dr. Yuh Hijikata Prof. Dr. Shigehiro Yamaguchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(30):7303-7307
The self-assembly of an amide-functionalized dithienyldiketopyrrolopyrrole (DPP) dye in aqueous media was achieved through seed-initiated supramolecular polymerization. Temperature- and time-dependent studies showed that the spontaneous polymerization of the DPP derivative was temporally delayed upon cooling the monomer solution in a methanol/water mixture. Theoretical calculations revealed that an amide-functionalized DPP derivative adopts an energetically favorable folded conformation in the presence of water molecules due to hydration. This conformational change is most likely responsible for the trapping of monomers in the initial stage of the cooperative supramolecular polymerization in aqueous media. However, the monomeric species can selectively interact with externally added fragmented aggregates as seeds through concerted π-stacking and hydrogen-bonding interactions. Consequently, the time course of the supramolecular polymerization and the morphology of the aggregated state can be controlled, and one-dimensional fibers that exhibit a J-aggregate-like bathochromically shifted absorption band can be obtained. 相似文献
14.
种子乳液聚合中复合乳胶粒结构形态的热力学分析 总被引:5,自引:0,他引:5
为了得到一种能够预测和控制乳胶粒结构形成的定量方法,本研究选用含有两 种聚合物乳胶粒(P_a和P_b)和水的体系作为模型体系来模拟种子乳液聚合体系,在 不考虑动力学因素的条件下,对乳胶粒可能出现的三种极限形态进行了热力学分析 。结果表明,最终乳胶粒稳定的结构形态不仅取决于体系中的P_a,P_b和水三者之 间的界面张力γ_(aw),γ_(bw)和γ_(ab),而且还取决于两聚合物的体积分数 V_a和V_b。形成P_a/P_b型正核壳结构乳胶粒的热力学必要条件是(γ_(aw)-γ_ (bw))/γ_(ab) > V_a~(2/3)-V_b~(2/3)和(γ_(aw)-γ_(ab))/γ_(bw) > (1- V_b~(2/3))/V_a~(2/3);形成P_a/P_b型反核壳结构乳胶粒的热力学必要条件是(γ _(aw)-γ_(bw))/γ_(ab) < V_a~(2/3)-V_b~(2/3)和(γ_(bw)-γ_(ab))/γ_(aw) > (1-V_a~(2/3))/V_b~(2/3)。对以聚丙烯酸酯为种子有机硅氧烷的乳液聚合体系 的初步研究结果表明,所得乳胶粒的结构形态与利用上述热力学关系式预测的结果 基本一致。 相似文献
15.
Xu Xiangling Ge Xuewu Yin Yadong Zhang Zhicheng Zou Ju Niu Aizheng 《Journal of polymer science. Part A, Polymer chemistry》1998,36(14):2631-2635
The seeded microemulsion polymerization of butyl acrylate was studied with γ-rays. The hydrodynamic diameter and its distribution of polymer particles in the seeded microemulsion before and after polymerization were determined with photon correlation spectroscopy (PCS). Though there were micelles in the microemulsion, it was found that new particle formation could be ignored during polymerization. The polymerization kinetics of the seeded microemulsion was investigated. The polymerization rate increases with the dose rate and added monomer content and decreases with the seed fraction. It was completely different from that for seeded emulsion polymerization. © 1998 John Wiley & Sons, Inc. J. Polym. Sci. A Polym. Chem. 36: 2631–2635, 1998 相似文献
16.
Qun Niu Mingwang Pan Jinfeng Yuan Xiao Liu Xiaomei Wang Haifeng Yu 《Macromolecular rapid communications》2013,34(17):1363-1367
A simple and elegant approach to fabricate anisotropic P(VC‐co‐AAEM)/PS nanoparticles with controllable morphologies via emulsifier‐free seeded emulsion polymerization is presented. Non‐cross‐linked P(VC‐co‐AAEM) seeds with hydrophilic surface are first synthesized through copolymerization of vinyl chloride (VC) and acetoacetoxyethyl methacrylate (AAEM), which are used to prepare P(VC‐co‐AAEM)/PS NPs with multiple bulges by SEP of styrene. Electron microscopy observation indicates that the content of AAEM in seeds is crucial to control the phase separation and morphology of the composite NPs. Moreover, the thermodynamic immiscibility between PVC and PS is the driving force for the formation of PS bulges onto the P(VC‐co‐AAEM) seeds. The resultant anisotropic NPs with non‐cross‐linked feature may promisingly serve as compatibilizers for further polymer processing.
17.
The novel poly (AN-BA-DFMA) was prepared via semi-continuous seeded emulsion polymerization. The resultant novel latex is characterized with FTIR and DSC. The reaction conditions for preparing the novel latex are optimized and studied in detail. Results show that the novel latex with small particle size and good stability and hydrophobicity can be obtained when the amount of emulsifiers is 6.0%, the mass ratio of OP-10 to SDBS is 2.0:1.0, and the amount of initiator and DFMA is 2.5% and 20%, respectively. Under such conditions, the conversion rate is high and the coagulation percentage is low. 相似文献