含聚合型乳化剂反相乳液体系的稳定性研究

以煤油为油相,丙烯酸钠水溶液为水相,自制的非离子聚合型乳化剂-Span80丙烯酸酯(Span80AA)、Span80和Twen80组成复合乳化剂,制备反相乳液。计算出Span80AA的HLB值,考察了乳化剂浓度、水相体积分数Φ及单体浓度对乳液类型及稳定性的影响。结果表明:HLB(Span80AA)=2.709;Span80AA、Span80和Twen80的最佳质量比为0.8∶0.3∶0.1。形成稳定的反相乳液理想条件是:复合乳化剂质量分数为6%~8%;Φ<57%;单体浓度为2.0~3.5 mol/L。     

用聚合型乳化剂制备反相乳液的研究

以丙烯酸钠水溶液为水相,煤油为油相,Span80甲基丙烯酸酯(Span80 MA)聚合型乳化剂、Span80和Twen80为复配乳化剂,制备反相乳液。计算聚合型乳化剂(Span80MA)的HLB值,考察了乳化剂浓度、水相体积分数φ及单体浓度对乳液类型及稳定性的影响规律。结果显示:HLB(Span80MA)=4.0;形成稳定的反相乳液理想条件为:Span80MA∶Span80∶Twen80=0.7∶0.5∶0.2;乳化剂浓度为7%;φ=50%;单体浓度为2.0～3.0 mol/L。     

聚合型乳化剂及其应用

聚合型乳化剂是一种新型乳化剂。本文介绍了聚合型乳化剂的类型和一般性质，通过传统乳化剂与聚合乳化剂比较，阐明了可聚合型乳化剂的优点，最后介绍了聚合型乳化剂的应用情况。     

乳化剂对AM/AMPS反相乳液性能影响研究

研究了Span80/Tween80、Span80/M-9、Span85/Tween85、Span80/OP-10、Span85/Tween80、M-3、Span85/M-9、Span85/OP-10八种非离子乳化剂复配体系对AM/AMPS反相乳液电导率、油水界面张力、乳液稳定指数、乳液微观结构等的影响。结果表明,适合AM/AMPS反相乳液体系的乳化剂为Span80/OP-10。     

可聚合乳化剂DNS-6对丙烯酸酯乳液稳定性的影响

使用可聚合乳化剂烯丙氧基壬基酚丙醇聚氧乙烯（10）醚硫酸铵（DNS-86）,通过半连续聚合工艺制备了水基丙烯酸酯乳液。考查了DNS-86对乳液的固含量、转化率、乳胶粒的大小及形态、Zeta电位以及各种稳定性（聚合稳定性、化学稳定性及冻融稳定性）的影响。与常规乳化剂十二烷基硫酸钠（SDS）制备的丙烯酸酯乳液性能进行了对比。结果表明,DNS－86因反应活性大,能与丙烯酸酯单体进行共聚,制得的乳胶粒大小均一,形态规整,乳液的稳定性得到改善。     

聚合型乳化剂

本文详细介绍了几种具有良好的乳化性能，可与多种单体共聚并能提高耐水性能的聚合型乳化剂以及合成工艺。     

丙烯酰胺反相乳液稳定性研究

以煤油为连续相介质,失水山梨醇单油酸酯(Span80)和烷基酚聚氧乙烯醚(OP-10)为复合乳化剂,采用电动搅拌器制备了丙烯酰胺的反相乳液。以50℃和20℃下乳液静置稳定性为考察指标,分别研究了转速、乳化时间、油水体积比、乳化剂含量、复合乳化剂HLB值、单体浓度对乳液稳定性的影响。得到了最佳乳化条件:转速2000 rpm,乳化时间30 min,油水体积比1.2∶1,乳化剂含量6%,复合乳化剂的HLB值为6.0,单体浓度15%。     

可聚合乳化剂对St-BA共聚乳液稳定性及羧基分布的影响

以苯乙烯(St)和丙烯酸丁酯(BA)为主单体,以丙烯酸和丙烯酸-2-羟基丙酯为功能单体制备了St-BA共聚乳液,研究了可聚合乳化剂烯丙氧基壬基酚聚氧乙烯(10)醚单磷酸(ANPEO10-P1)对共聚乳液的聚合稳定性、化学稳定性、羧基分布及乳胶膜耐水性、剥离强度等性能的影响。结果表明:与常规乳化剂十二烷基硫酸钠(SDS)相比,使用可聚合乳化剂ANPEO10-P1能有效地改善乳液的性能。通过电导滴定发现,乳化剂对乳液不同区域的羧基分布有较大的影响,因而影响乳胶膜的耐水性和剥离强度。     

反应型乳化剂对丙烯酸酯乳液稳定性和粘度的影响

使用反应型乳化剂烯丙氧基壬基酚聚氧乙烯(10)醚硫酸铵(DNS-86)和常规乳化剂十二烷基硫酸钠(SDS)制备丙烯酸酯乳液,研究了这两种乳化剂对乳液稳定性的影响,比较了两种乳化剂对乳液粘度的作用方式,探讨了反应型乳化剂对乳液粘度的影响机理。结果表明:与常规乳化剂SDS相比,使用反应型乳化剂DNS-86制得的乳液稳定性得到提高,当DNS-86的用量为2.0%时,乳液的稳定性最好。乳液的粘度随乳化剂用量的增大呈锯齿状增加。使用DNS-86制备的乳液粒径较大、粒径分布较窄、粘度较小。     

丙烯酸铵反相微乳液体系研究

为了制备一个均匀稳定且固含较高的丙烯酸铵反相微乳液体系,通过对微乳液体系电导率、丁达尔现象、稳定性等参数的测定,考察了连续相、乳化剂、HLB值、水相、电解质以及助乳化剂等因素对丙烯酸铵微乳液体系的影响,最终得到了由Isopar M异构烷烃以及Span80/OP-10复配乳化剂构成的丙烯酸铵反相微乳液体系。该体系单体固含达17.65%,均匀稳定,长期放置不分层。     

聚氨酯预聚体——可聚合乳化剂用于MMA乳液聚合动力学及聚合稳定性研究

将合成的聚氨酯预聚体可聚合乳化剂（APUA）用于甲基丙烯酸甲酯（MMA）乳液聚合体系中，研究了不同引发剂体系和乳化剂对聚合体系的聚合稳定性和动力学影响，并与SDS乳化剂进行了对照。结果显示，用油溶性引发剂（AIBN）和水溶性引发剂（K2S2O8）都能引发该体系的聚合反应，而且聚合速率和转化率都相当高。用AIBN作引发剂时，APUA和SDS两种乳化所对应的动力学曲线不同，但APUA比SDS的聚合速率大得多，其分别类似于微乳液聚合（miniemulsion)和微悬浮聚合（microsuspention)，且聚合过程中会产生一定的凝胶。当乳化剂APUA用量适合时，凝胶量极少，聚合体系是稳定的；而当用K2S2O8作引发剂时，两乳化剂对应动力学曲线相似，聚合过程不产生凝胶。但当引发剂用量较大并以APUA作乳化剂时，在聚合过程中会出现全部粒子突然粗化现象，而以SDS作乳化剂没有出现这一现象。     

聚醋酸乙烯乳液稳定性能的研究——乳化剂对乳液聚合稳定性的影响

采用半连续乳液聚合的方法,合成聚醋酸乙烯乳液,探讨乳化剂的种类,配比及浓度对乳液聚合稳定性和粘度的影响。该乳液稳定性能良好,木-木压缩剪切强度达12MPa以上,可作为多孔性物质的胶粘剂使用。     

AM/AMPS/SSS三元反相乳液聚合体系稳定性研究

以丙烯酰胺(AM)为主单体、2-甲基-2-丙烯酰胺基丙磺酸(AMPS)、对苯乙烯磺酸钠(SSS)为抗温抗盐单体,以白油为连续相,Span 80/Tween 80为复合乳化剂,制得了AM/AMPS/SSS三元反相乳液聚合体系,考察了HLB值、乳化剂浓度、油水比、pH值、搅拌时间、搅拌速度对乳液稳定性的影响。结果表明,乳化剂含量为6%～7%(体系总量),HLB值为5.89,体系pH=8,油水体积比为1.8∶1,搅拌时间30～40 min,搅拌速度为500 r/min时得到稳定的反相乳液体系,适合进行三元反相乳液聚合。     

Effect of polyoxyethylene emulsifier composition on the course of emulsion polymerization of vinyl acetate

Three different emulsifier types from vinyl acetate monomer and methoxypolyoxyethylene (35: 65, 27: 73 and 19: 81wt: wt%) were prepared in the presence of benzoyl peroxide using a macroradical initiator technique. Fourier transform infrared spectroscopy and ¹H nuclear magnetic resonance were carried out to confirm the structure of the copolymers obtained (emulsifiers). The emulsion polymerization of vinyl acetate initiated by sodium persulphate as an initiator in the presence of non-ionic (polyoxyethylene (POE) type) emulsifier has been kinetically investigated. The rate of polymerization was found to be proportional to the 0·33, 0·40 and 0·44 power of the emulsifier concentration and to the 0·71, 0·79 and 0·87 power of the initiator concentration. The apparent activation energy was found to be 135, 56·5 and 38kJmol^-1 for 65wt%, 73wt% and 81wt% POE, respectively. The particle size was observed to increase with increasing initiator concentration and to decrease with increasing emulsifier concentration. The reaction order with respect to the emulsifier concentration (number of particles versus emulsifier concentration) was found to be 0·10, 2·05 and 0·89 for 65wt%, 73wt% and 81wt% POE, respectively. ©1997 SCI     

反应型乳化剂的合成及其在乳液聚合中的应用

合成了2类可聚合乳化剂马来酸酐单酯硫酸钠和马来酸酐单酯磺酸钠，测定了产物的纯度和临界胶束浓度，研究了它们在苯乙烯/丙烯酸丁酯/丙烯酸三元乳液聚合中的转化率。以十二烷基硫酸钠为参照物，用可聚合乳化剂制备的乳液对电解质的稳定性有很大的提高，干胶膜的耐水性和拉伸强度得到了显著改善。     

The inverse emulsion polymerization of acrylamide with pentaerythritolmyristate as emulsifier. 1. Experimental studies

The inverse emulsion polymerization of aqueous acrylamide solutions in isooctane as dispersing media with the emulsifier pentaerythritolmyristate and an oil-soluble azo initiator was studied, particularly with respect to the influence of the chemically pure emulsifier. In this free radical polymerization, a water-in-oil emulsion with droplet sizes around 10μm is converted into a latex with average particle diameters between 80 and 200nm containing a polymer with molar masses up to 16×10⁶gmol^-1 Kinetic data were measured by adiabatic as well as by isothermal calorimetry. The influences of various parameters on polymerization kinetics, particle numbers and molar mass averages were studied. Experimental results show a positive influence of the emulsifier concentration on the reaction rate and indicate the dominance of a bimolecular termination re-action with respect to the polymer radicals above a certain initiator concentration. © 1998 SCI.     

AM/NVP/DMMAC共聚物反相乳液聚合研究

采用反相乳液聚合方法,以煤油为介质,司班80为乳化剂,十二胺为助乳化剂合成了疏水缔合聚合物AM/NVP/DMMAC,研究了反应温度、引发剂用量、反应时间、疏水单体DMMAC用量、NVP用量等对反应和聚合物性能的影响。结果表明,合成聚合物的适宜条件为:引发剂浓度0.1%,疏水单体DMMAC加量为0.4%,NVP加量为5%,反应温度40℃。     

The inverse emulsion polymerization of acrylamide with pentaerythritolmyristate as emulsifier. 2. Mathematical modelling

A mathematical model of the inverse emulsion polymerization of aqueous acrylamide solutions in isooctane as dispersing media with the chemically pure emulsifier pentaerythritolmonomyristate and an oil-soluble azo initiator has been developed. A Monte Carlo method was used successfully to calculate the kinetics, molar mass averages and average particle sizes. The computation time of the method was reduced by calculating the chain length of the polymer molecules via the life-time of the radicals. It is shown that a few assumptions based on the mirror image of an ideal conventional emulsion polymerization with Smith–Ewart case 2 kinetics are sufficient to comprehensively describe the experimental findings. © 1998 SCI.