Synthesis of acrylate microemulsion modified by alkoxy silane

An acrylate emulsion was modified by adding vinyltriisopropoxy silane （trade name C-1706）. By adding the multiple emulsifier which consists of an anionic emulsifier, sodium dodecyl benzene sulfonate （SDBS） and nonionic emulsifier, octyl phenolic divinyl oxide （OP-10）, the acrylosilane microemulsion was synthesized by seeded emulsion polymerization. The influential factors including the kind and the adding amount of emulsifiers and the monomer variety of alkoxy silane and the added methods which influence on the properties of the microemulsion were investigated. It is found that SDBS and OP-10 as multiple emulsifiers with mass ratio of 1：1 and the adding amount of 2.5%-3.5% can act on co-effect for emulsion polymerization. The C-1706 possesses bulky isopropoxy substituent that can reduce hydrolysis reactivity during the polymerization process, so as to not only make the process smoothly but also advance the store stability of the emulsion. Moreover, the latter-addition mode of C-1706 can restrain its hydrolysis activity and polycondensation reaction during the polymerization process of the emulsion. The structure, the film cross section, the particle size and its distribution of the microemulsion were analyzed by the Fourier Transform Infrared Ray Spectrum （FTIR）, Scanning Electron Microscopy （SEM） and a particle size analyzer, respectively. The results show that the particle diameter of the modified microemulsion can be controlled between 50 and 70 nm and its film hardness is 7.3. Only adding 1.5% of C-1706 into the system of emulsion polymerization can apparently improve the weathering resistance of the microemulsion, which undergo degradation with chromatism（△E） is 1.6 after 3 600 hours of QUV-aging.     

硅烷偶联剂改性水性丙烯酸酯乳液的制备及性能

以丙烯酸丁酯（BA）和甲基丙烯酸甲酯（MMA）、丙烯酸（AA）和γ-甲基丙烯酰氧基丙基三甲氧基硅烷（KH-570）为单体,过硫酸铵为引发剂,十二烷基苯磺酸钠（SDBS）和烷基酚聚氧乙烯醚（OP-10）为复合乳化剂,采用半连续乳液聚合法合成了复合胶黏剂乳液.采用红外光谱对聚合物结构进行了表征,热重分析研究了聚合物胶膜的热稳定性.接触角的测定表征了聚合物膜的表面性能.研究了反应温度,引发剂和乳化剂用量等因素的影响.结果表明,聚合反应速率随着反应温度的提高而加快.随着引发剂和乳化剂用量的增加,乳液的粒径减小,乳液更加稳定.硅改性后的聚合物具有较好的耐水性和热稳定性.     

水性苯丙微乳液制备工艺及其性能研究

采用预乳化种子微乳液聚合方法制备环保型水性苯丙微乳液涂料,并对聚合方法、温度、软/硬单体的配比以及乳化剂用量和配比对乳液及其涂膜性能的影响进行了研究。结果表明:使用SDS/OP-10复合乳化剂,采用预乳化种子聚合方法制得固含量为47.2%的微乳液,而乳化剂与其它方法相比降低了近一半;综合微乳液性能考虑,软/硬单体配比mMMA∶mSt∶mBA=35∶20∶26较合适;乳液合成的两个阶段的乳化剂用量:mA-102∶mDNS-86=2.5:1,合成的微乳液具有很好的稳定性,涂膜有较好的耐水性。     

外墙用硅丙乳液的合成研究

针对有机硅改性苯丙乳液所具有的优点,本文通过预乳化种子乳液聚合和水解抑制技术,利用活性有机硅单体改性苯丙乳液,制备稳定性和成膜性能优异的外墙用硅丙乳液,并对有机硅用量、乳化剂用量及比例、功能单体加入量等因素进行了实验研究。实验结果表明,在有机硅烷的用量控制在5%~8%,复合乳化剂比例为SDS/OP-10=2/1,AA的用量为1.43%的条件下,合成的硅丙乳液的性能为:附着力1级,粒径95nm,硬度6H,粘度22s,吸水率5.92%,转化率99.02%,固体质量分数37.42%。实验得到的硅丙乳液因粒径较小,可以提高乳液对颜料的润湿力和包覆力,赋予乳胶漆较高的光泽,提高乳胶漆对墙体的渗透能力和装饰效果,而且较窄的粒径分布,可以提高乳液及乳胶漆的储存稳定性及综合性能。因此,本实验得到的硅丙乳液是良好的外墙涂料基料。     

乙烯基三乙氧基硅烷改性丙烯酸酯乳液合成工艺的优化研究

采用半连续种子乳液聚合工艺,利用单因素和正交实验设计方法,使用由非离子型乳化剂辛烷基酚聚氧乙烯醚（OP-10）与阴离子型乳化剂十二烷基硫酸钠（SDS）复配的复合乳化剂,以及反应型乳化剂马来酸酐单酯硫酸钠（OS）合成平均粒径为190nm的有机硅改性丙烯酸酯乳液．研究乳化剂用量、引发剂用量、有机硅用量、聚合搅拌速度、单体滴加时间、软硬单体配比、聚合温度7个因素对单体转化率的影响．极差分析各因素对单体转化率影响的主次顺序为：乳化剂用量〉软硬单体质量配比〉有机硅用量〉单体滴加时间〉聚合搅拌速度〉引发剂用量〉聚合温度．得出制备有机硅改性丙烯酸酯乳液最佳工艺条件：乳化剂用量4％,引发剂用量0．6％,有机硅用量8％,聚合搅拌速度180r／min,单体滴加时间2h,聚合温度75℃,软硬单体配比43：54．     

交联型醋-丙乳液的合成及性能

以醋酸乙烯酯(VAC)、丙烯酸丁酯(BA)等为主要原料,TAC和HEA为交联单体,采用半连续预乳化种子乳液聚合法合成了醋-丙乳液,讨论了各工艺条件对乳液性能的影响。用激光粒度分布仪、红外光谱仪(FTIR)、静态接触角测试仪等测试手段,对合成产物进行了性能和结构表征。结果表明,单体质量比m(VAC):m(BA)=3:2、乳化剂OP-10和SDS总用量为单体的3.5%、引发剂APS用量为单体的0.6%时,单体转化率可高达98.3%,凝胶率可以控制在0.5%左右;交联单体TAC的用量为单体的1.6%时,聚合物吸水率为8.5%,膜与水的接触角为69.5°。     

The Growth of Latex Particles during the VAc/BA Copolymerization

The semi-continuous seeded emulsion eopolymerization of vinyl acetate and butyl acrylate was carried out with hydroxyethyl cellulose as a colloid stabilizer. The morphology of the latex particle and the relationship between the reaction time and the average particle diameter and/or the conversion ratio during the polymerization were invstiguted. The experimental results shaw that the morphology of the latex particle possesses the stable sterie construction. In the seeded polymerizution, the average particle diameter of latex decreased while the conversion ratio increased. At the second term of the emulsion copolymerization （the growth stage of particle size）, the latex particle average diameter increased with copolymerization continuously, but the instantaneous conversation ratio was not large, so it was very necessaO to properly prolong the time during the holding temperature stage.     

复合离子型乳化剂对淀粉接枝丙烯酰胺的聚合反应作用

采用反相乳液聚合法,合成了淀粉接枝聚丙烯酰胺的反相乳液产品,研究了反相乳液聚合工艺条件。考察了乳化剂种类,乳化剂组成、乳化剂用量以及乳液形成方式对单体转化率、接枝率、乳胶粒径和产品特性黏度的影响。结果表明,以脂肪酸(盐)为乳化剂,乳液具有良好的稳定性和低温溶解性;将表面活性剂进行复配得到的混合乳化剂的乳化效果优于单一乳化剂。以油酸与油酸钠复配物为乳化剂时,合成了单体转化率98%,接枝率80%,特性黏度1 300 mL/g的淀粉接枝丙烯酰胺反相乳液产品。考察了过硫酸铵、过硫酸铵-尿素引发剂体系对单体转化率、产品特性黏度的影响。     

Nonionic polymerizable emulsifier in high-solids-content acrylate emulsion polymerization

Stable high-solids-content acrylate emulsion were obtained with a nonionic polymerizable emulsifier allyloxy nonylphenoxy poly (ethyleneoxy) (10) ether (ANPEO10), and a conventional emulsifier OP-10 as a reference sample. 1H NMR proves that the polymerizable emulsifier ANPEO10 has been incorporated into the resulted acrylate polymers. TEM demonstrates that there are some differences in the particle morphologies. AFM proves that the polymerizable emulsifier ANPEO10 migrating to the surface of the emulsion film was much less than the conventional emulsifier OP-10. The polymerizable emulsifier ANPEO10 can enhance the adhesion with glass plate compared to the conventional emulsifier. Furthermore, with increasing amount of emulsifier, the surface free energy of the films first decreased and then increased, and the adhesion with glass plate is initially enhanced and then attenuated. The water-resistance and solvent-resistance of the films prepared by the polymerizable emulsifier ANPEO10 are superior to those prepared by the conventional emulsifier OP-10.     

准单分散阳8离子型聚甲基苯乙烯胶乳粒子的制备

采用偶氮对2－脒基丙烷盐酸盐（V－50）为引发剂通过无乳化剂乳液聚合方法制备尺寸均一的阳离子聚甲基苯乙烯（PMS）胶乳粒子。详细讨论聚合条件,如引发剂浓度、单体浓度、离子强度、搅拌速度对聚合速率、粒子尺寸及分布的影响。最终获得制备单分散无乳化剂阳离子型聚甲基苯乙烯乳粒子的方法。     

乳化剂对核壳乳液聚合体系的影响

本文采用半连续-预乳化工艺制备了表层羧酸化的聚丙烯酸丁酯／聚（甲基丙烯酸甲酯-衣康酸）（PBA／P（MMA—ITA））核壳乳液。通过对乳液粒径及其分布、凝聚率和表面张力的分析研究了乳化剂种类、配比、用量以及功能单体等因素对聚合体系稳定性的影响,采用非水滴定法、傅立叶红外光谱仪（FTIR）、差示扫描量热仪（DSC）、透射电子显微镜（TEM）等方法对乳胶粒子进行了表征。实验结果表明：OP—10引入乳化体系,使聚合体系的稳定性增加,但随着OP—10用量的增加,乳胶粒子粒径增大、粒径分布变宽,聚合体系的稳定性降低;复合乳化剂SDS／OP—10用量增加,乳胶粒子粒径减小,聚合体系的稳定性增加;极性单体ITA的使用导致聚合体系的稳定性降低。分析结果还证明ITA已成功参与了壳层的聚合反应,乳胶粒子具有明冠的核/壳结构。     

甲基丙烯酸系四元共聚乳液的研制

以苯乙烯、丙烯酸丁酯以及丙烯酸2-乙基已酯作为主单体，甲基丙烯酸作为功能单体，十二烷基硫酸钠(SDS)和OP-10作为复合乳化剂，采用乳液聚合法合成四元共聚物苯丙乳液．通过对单体配比、引发剂用量、乳化剂配比及用量的实验研究，制得化学稳定性、机械稳定性、稀释稳定性均佳，粘度适宜乳液．     

Characteristics of Self-Healing Microcapsules for Cementitious Composites

Urea formaldehyde/epoxy resin microcapsules were prepared by an in situ polymerization method and the effect of emulsifier on the syntheses process of the microcapsules was discussed. The surface morphology of the microcapsules was observed by optical microscopy and scanning electron microscopy(SEM). Chemical structure was characterized by Fourier transform infrared spectroscopy(FTIR). Thermal stability was obtained using simultaneous thermal analysis(STA). The microcapsules were composed of urea-formaldehyde resin shell and epoxy resin core. Emulsifier played an important role in the polymerization process when the core material was packed by pre-polymer, so the effects of different emulsifiers(OP-10, SDS and SDBS) were discussed respectively. Results showed that the particle size of the microcapsules was uniform when SDBS as an emulsifier. Microcapsules showed good thermal stability below 240 ℃ and the initial decomposition temperature of the microcapsules was 265 ℃. The core materials released after microcapsules rupturing, which could be proven by the images of SEM. When implanted in cementitious composites, complete shape of microcapsules and good interface between microcapsules and cement specimen substrate could also be observed.     

甲基丙烯酰氧乙基三甲基氯化铵/丙烯酰胺反相乳液的聚合及表征

以Span 80、OP 10为乳化剂,K2S2O8、Na2S2O4、V 044为引发剂,以汽油为分散介质, 用反相乳液聚合法制备出甲基丙烯酰氧乙基三甲基氯化铵 /丙烯酰胺共聚物,并且用粒度分布仪及红外光谱进行了分析表征。结果显示,随乳化剂用量及引发剂用量增加,共聚物相对分子质量下降;乳胶粒子大小受引发剂、乳化剂、交联剂的加量及放置时间等条件的影响而变化。     

环氧-丙烯酸胶乳型互穿聚合物网络稳定性的研究

采用乳液聚合技术,合成了环氧-丙烯酸LIPN,通过对聚合物乳液的收率和Ca2 稳定性的测定,对环氧树脂用量、复合乳化剂的配比、复合乳化剂用量、聚合工艺、水溶性单体以及引发剂用量等影响环氧-丙烯酸LIPN聚合物乳液稳定性的因素进行了分析研究.     

核壳结构乳液胶粘剂的研究

本文研究了乙酸乙烯酯－丙烯酸丁酯－甲基丙烯酸体系的乳液聚合反应，通过“种子”乳液聚合方法得到了核壳结构乳液，并将它们的性能与均匀共聚合乳液作了测试与比较。     

聚丙烯酸钠/2-丙烯酰胺基-2-甲基丙磺酸吸水树脂的制备

采用反相乳液聚合法制备丙烯酸钠/2-丙烯酰胺基-2-甲基丙磺酸二元共聚物吸水树脂,考察了聚合过程中搅拌速率、油水相质量比和乳化剂用量等因素对吸水树脂粉末粒径的影响,并采用红外光谱对吸水树脂的分子结构进行了表征。结果表明:搅拌速率600 r.min-1,油水质量比1.8∶1时,合成的吸水树脂粒径最小,粒径分布最窄;乳化剂质量分数9%时,能满足对吸水树脂粒径和粒径分布以及乳液稳定性的要求。     

ACR的组成对PVC性能的影响

通过种子乳液聚合方法合成聚丙烯酸丁酯胶乳和丙烯酸丁酯与苯乙烯共聚胶乳,然后采用乳液聚合法接枝苯乙烯和甲基丙烯酸甲酯,制备出具有核-壳结构的丙烯酸酯类抗冲改性剂(ACR).以ACR作为聚氯乙烯(PVC)的抗冲击改性剂,考察了具有不同组成的ACR对改性后的PVC性能的影响.     

MMA—BA—DMAEMA乳液共聚合体系的稳定性

采用间歇及半连续乳液聚合方式,合成得到了甲基丙烯酸甲酯－丙烯酸丁酯－甲基丙烯酸二甲氨基乙酯三元共聚物胶乳。系统研究了乳化剂种类和浓度,聚合温度、官能单体含量和乳化单体进料方式及进料速率对聚合体系稳定性的影响,试验结果表明,对含有氨基官能单体的共聚合体系,合适的乳化剂体系只能通过聚合稳定性试验确定,单体乳化稳定性试验并不能提供有价值折信息,试验结果还表明,宫能单体甲基丙烯酸二甲氨基乙酯的含量对聚合体     

微波辐射丙烯酸酯乳液聚合动力学研究

利用Discover微波精确有机合成系统,以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为聚合单体、过硫酸钾(KPS)为引发剂、十二烷基硫酸钠(SDS)为乳化剂进行乳液聚合。考察了微波辐射功率对乳液聚合反应的影响,分别考察了引发剂的质量,乳化剂质量,甲基丙烯酸甲酯质量,丙烯酸丁酯质量及反应温度,还对微波聚合反应动力学方程进行了研究。利用热重分析仪,差示扫描量热仪和傅立叶变换红外光谱仪对聚合物乳液的性能进行了测试与结构表征。实验结果表明,反应体系选择60 W为微波辐射条件,m(KPS)为0.06 g、m(SDS)为0.27 g、m(MMA)和m(BA)均为3 g,反应温度为343 K,测得聚合反应的活化能Ea=96.957 1 kJ/mol,建立了单模聚焦微波辐射乳液聚合的动力学方程:Rp=k[n(KPS)]1.107 9[n(SDS)]0.616 4[n(MMA)]1.205 9[n(BA)]-0.228。