分散剂及复合介质对石蜡-聚苯乙烯微球合成的影响

通过悬浮聚合法合成石蜡-聚苯乙烯微球,研究了合成过程中复合介质的配比和用量以及分散剂种类和用量对微球粒径及其分布的影响。实验结果表明:采用聚乙烯醇作分散剂,更有利于合成小粒径、高产率的石蜡-聚苯乙烯微球,悬浮聚合体系中水-乙醇复合介质的最佳体积配比和用量分别为1:2.5和150mL。     

石蜡聚苯乙烯微球的制备

通过悬浮聚合技术合成了石蜡聚苯乙烯微球，研究了合成过程中引发剂浓度及交联剂用量对微球粒径及其分布的影响。     

石蜡聚苯乙烯微球的制备Ⅲ.壁膜的选择及包覆研究

通过悬浮聚合技术合成了以聚苯乙烯为壁材、以石蜡为芯材的储能微球,研究了壁膜的选择及包覆程度。结果表明:聚苯乙烯很适合作为石蜡储能微球的壁膜,合成的石蜡聚苯乙烯微球包覆完整。     

石蜡聚苯乙烯微球的制备

用悬浮聚合法制备石蜡聚苯乙烯微球。研究了合成过程中搅拌器的位置、搅拌速度、升温速度和反应时间等对微球粒径分布及其产率的影响。     

化妆品用PMMA微球的制备及应用研究

采用悬浮聚合制备了平均粒径分别为~6μm,~10μm以及~15μm的聚甲基丙烯酸甲酯微球。分别考察了单体用量、均质条件、分散剂用量等因素对聚合稳定性及微球粒径的影响。结果表明单体用量会极大的影响聚合稳定性,单体用量不超过20%时聚合过程稳定。均质条件会影响微球粒径。均质机转速越大,微球粒径越小。分散剂用量对微球粒径影响较小将制备的不同粒径微球进行肤感评价,结果表明粒径为10μm的微球肤感最好。     

悬浮聚合法合成交联苯乙烯-丙烯腈共聚物的研究

通过悬浮聚合实验,研究了交联剂种类、链转移剂质量分数、分散剂复配体系对合成交联聚苯乙烯-丙烯腈的悬浮聚合体系的稳定性影响。通过傅立叶变换红外光谱(FTIR)法和索式提取器来表征交联共聚物结构和测量聚合物凝胶含量。结果表明:丙烯酸酯类比二乙烯基苯交联剂更适合提高交联苯乙烯-丙烯腈合成的悬浮聚合稳定性;随着转移剂质量分数的增加,聚合稳定性上升;少量的有机分散剂聚乙烯醇与无机分散剂羟基磷酸钙复配有助于减小交联微球的粒径。     

无外加表面活性剂的苯乙烯悬浮聚合

针对传统悬浮聚合制备聚苯乙烯颗粒粒径分布宽、有效粒子收率低的问题,采用过硫酸铵/磷酸钙复合分散剂体系,在无外加表面活性剂情况进行苯乙烯悬浮聚合,制备了聚苯乙烯珠粒。通过对聚合稳定性、聚苯乙烯珠粒粒径及分布的测定与分析,考察了磷酸钙、过硫酸铵的用量及比例对悬浮聚合的影响,并分析了过硫酸胺对悬浮聚合的分散稳定机理。结果表明,当过硫酸铵和磷酸钙的用量分别为单体质量的0.01%和1.00%时,悬浮聚合体系稳定,得到的粒子透明性好,平均粒径为1.35 mm,粒径分布窄;通过改变过硫酸铵和磷酸钙的用量,可以调节聚苯乙烯珠粒的平均粒径。     

聚合时间、分散介质的配比对聚苯乙烯高分子微球表征的影响

本文采用分散聚合法制备聚苯乙烯(PS)高分子微球,通过正交实验对其表征进行研究,从而得出聚合时间、分散介质的配比对聚苯乙烯微球的粒径、分子量的影响。扫描电镜结果表明:制得的聚苯乙烯微球的平均粒径为2.24μm;黏度法测定聚苯乙烯高分子微球的平均分子质量为4.25×105;实验结果表明,聚合时间和分散介质配比对聚苯乙烯高分子微球的粒径和分子量有较大的影响。     

高交联度聚苯乙烯微球聚合工艺的研究

以二乙烯基苯(DVB)为交联剂,通过悬浮聚合合成了主要粒径范围为0.425～0.850 mm的高交联度聚苯乙烯(PS)微球。考察了反应温度、反应时间、搅拌速率、分散剂种类及用量和水油质量比对微球粒径的影响,确定了最佳聚合工艺:采用分段升温且增加低温段反应时间,搅拌速率为110～130 r/min,主分散剂聚乙烯醇(PVA)质量分数为0.076%,助分散剂磷酸三钙(TCP)质量分数为0.053%,水油质量比为(2～2.6)∶1。     

原位分散聚合法聚合物微球PMMA包覆尿嘧啶的合成及表征研究

本课题采用分散聚合法对抗肿瘤药物进行了原位包覆,研究了其合成工艺以及聚合的机理,并探究了分散剂和反应介质对微球的粒径、粒度分布和包药率的影响。实验结果表明:当无水乙醇取40 g,蒸馏水取60 g所组成的反应介质时,能够制得理想粒径的的聚合物微球,且聚合物微球的粒度分布较为均匀。当单体质量为15 g时,取分散剂3 g可得到理想粒径的微球。当分散剂占单体质量15%～20%时,会取得较高的包覆率。单体聚合的转化率随着引发剂用量的增加而增加,且单体聚合的"高发期"在反应开始后1 h内。     

Preparation of polymer‐supported polyethylene glycol and phase‐transfer catalytic activity in benzoate synthesis

The crosslinked polymeric microspheres (GMA/MMA) of glycyl methacrylate (GMA) and methyl methacrylate (MMA) were prepared by suspension polymerization. Polyethylene glycol (PEG) was grafted on GMA/MMA microsphers via the ring‐opening reaction of the epoxy groups on the surfaces of GMA/MMA microspheres, forming a polymer‐supported triphase catalyst, PEG‐GMA/MMA. The Phase‐transfer catalytic activity of PEG‐GMA/MMA microspheres was evaluated using the esterification reaction of n‐chlorobutane in organic phase and benzoic acid in water phase as a model system. The effects of various factors on the phase transfer catalysis reaction of liquid–solid–liquid were investigated. The experimental results show that the PEG‐GMA/MMA microspheres are an effective and stable triphase catalyst for the esterification reaction carried out between oil phase and water phase. The polarity of the organic solvent, the ratio of oil phase volume to water phase volume and the density of the grafted PEG on PEG‐GMA/MMA microspheres affect the reaction rate greatly. For this investigated system, the solvent with high polarity is appropriate, an adequate volume ratio of oil phase to water phase is 2:1, and the optimal PEG density on the polymeric microspheres is 15 g/100 g. Triphase catalysts offer many advantages associated with heterogeneous catalysts such as easy separation from the reaction mixture and reusability. The activity of PEG‐GMA/MMA microspheres is not nearly decreased after reusing of 10 recycles. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

反相悬浮法制备磁性高分子微球的研究

本文采用反相悬浮法,通过聚乙二醇的缩醛化反应,制备了具有灵敏磁响应性、表面富含羟基的微米级的磁性高分子微球。主要探讨了反应时间、聚乙烯醇浓度、搅拌速度、戊二醛(GA)用量及磁流体用量的变化对磁性高分子微球制备及性质的影响,用红外(FTIR)、激光粒径分析仪、扫描电子显微镜(SEM)、振动样品磁强计(VSM)进行表征。结果表明,所制备磁球表面羟基含量高,分散性好,磁含量高,具有超顺磁性。     

载药淀粉微球的合成研究

以可溶性淀粉为原料,环氧氯丙烷为交联剂,Span60为乳化剂,甲苯和蓖麻油的混合物为油相,采用逆相悬浮交联聚合法合成淀粉微球。实验运用正交优化设计,选择淀粉浓度、油水相之比、乳化剂用量和交联剂用量四个因素为考察对象,对淀粉微球的制备条件进行了优化。利用红外（IR）、扫描电镜（SEM）、激光粒度分析仪（LPA）等对产物进行了表征。     

Facile fabrication of polystyrene/halloysite nanotube microspheres with core–shell structure via Pickering suspension polymerization

In this article, a facile method for fabrication of core–shell nanocomposite microspheres with polystyrene (PS) as the core and halloysite nanotubes (HNTs) as the shell via Pickering suspension polymerization was introduced. Stable Pickering emulsions of styrene in water were prepared using HNTs without any modification as a particulate emulsifier. The size of the Pickering emulsions varied from 195.7 to 26.7?μm with the water phase volume fraction increasing from 33.3 to 90.9?%. The resulting Pickering emulsions with the water phase volume fraction of above 66.7?% were easily polymerized in situ at 70?°C without stirring. HNTs played an important role during polymerization and effectively acted as building blocks for creating organic–inorganic nanocomposite microspheres after polymerization. The sizes of PS/HNTs microspheres were roughly in accord with that of the corresponding emulsion droplets before polymerization. The effect of the water phase volume fraction on the stability of Pickering emulsions and the morphologies of nanocomposite microspheres was investigated by optical microscopy, confocal laser scanning microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and so on.     

Preparation and Properties of Thermoplastic Expandable Microspheres With P(VDC-AN-MMA) Shell by Suspension Polymerization

Thermoplastic expandable microspheres (TEMs) having core/shell structure were prepared via suspension polymerization with vinylidene chloride (VDC), acrylonitrile (AN), and methyl methacrylate (MMA) as monomers and i-butane as blowing agent. TEMs were about 20 µm in diameter and had a hollow core containing i-butane. The influence of the monomer feed ratio and blowing agent content was researched. When the monomers composition of 58.4 wt% VDC, 28 wt% AN, 13.6 wt% MMA, and 32 wt% i-butane in oil phase, suspension polymerization could yield TEMs having good expansion properties. The maximum expansion volume was 25 times of original volume at about 111–120°C, the blowing agent content in microspheres was about 21.5 wt%. The T_m.e, T_o.e, and T_o.s. of the TEMs increased with the VDC content in the polymerizable monomers decreasing.     

Controllable preparation,rheology, and plugging property of micron‐grade polyacrylamide microspheres as a novel profile control and flooding agent

A series of micron‐grade polyacrylamide microspheres were prepared by inverse suspension polymerization of acrylamide (AM) and N,N′‐methylene bisacrylamide (MBA) in oil phase, with Span80 and Tween80 as dispersion stabilizers, and ammonium persulfate (APS) as an initiator. The conversion rate and coagulum rate were introduced to optimize the inverse suspension polymerization conditions of micron‐grade polyacrylamide microspheres. The swelling property of polyacrylamide microspheres in aqueous solution and the rheology of polyacrylamide microspheres suspension were characterized. The matching factor was introduced to characterize the matching relationship between the particle size of polyacrylamide microspheres and pore‐throat size of reservoirs. The optimized synthesis results show that the conversion rate is high, and the coagulum rate is low when the mass ratio of Span80 to Tween80 is 3 : 1. The particle size of the polyacrylamide microspheres is controlled by varying the concentration of dispersion stabilizer. The polyacrylamide microspheres show an obvious swelling property, which depends on the concentration of NaCl and temperature. The polyacrylamide microspheres suspension shows different rheological properties at different temperature and shear rate. When the temperature is low, it behaves as pseudoplastic fluid, dilatant fluid and quasi‐newtonian fluid in turn with the increase of shear rate. When the temperature is high, it behaves as dilatant fluid and quasi‐newtonian fluid in turn with the increase of shear rate. The micron‐grade polyacrylamide microspheres prefer to plug sand pack with optimal matching factor. When the matching factor is 1.35–1.55, the polyacrylamide microspheres can be transported into the deep area of sand pack, and the ultimate plugging rate is more than 85%, which indicates that the matching factor is an effective parameter to evaluate the matching relationship between polyacrylamide microspheres and reservoirs. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1124‐1130, 2013     

聚氨酯微球的制备方法及应用

介绍了聚氨酯微球的几种制备方法及其特点,包括悬浮聚合法、反相悬浮聚合法、自乳化法、分散聚合法、SPG膜乳化法;并对乙烯基聚合物和有机刚性纳米粒子改性聚氨酯微球和应用进行了概述.