改性聚丙烯酸酯乳液的合成及表征.pdf

西安石油大学
硕士学位论文
改性聚丙烯酸酯乳液的合成及表征
姓名:聂莹
申请学位级别:硕士
专业:应用化学
指导教师:刘祥
20070515
中文摘要
论文题目:改性聚丙烯酸酯乳液的合成及表征
专业:应用化学
硕士生:聂莹(签名)
指导教师:刘样(签名)-」
摘要
本文以甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸2-乙基己酯和甲基丙烯酸缩水甘油酯
等为单体,过硫酸铵-亚硫酸氢钠氧化还原体系为引发剂,通过种子乳液聚合法制备了以
PMMA-BA为“核”、 PEHA-GMA为“売”的微相复合乳液。用透射电镜观察了乳胶粒子的
形态特征,表征了乳液聚合物经不同热处理温度热处理后的玻璃化转变温度、力学性能
和吸水率。实验表明,当核组分乳液聚合和壳组分聚合反应温度为60℃,加料时间在
40min和60min,加料完成后再反应60min,单体的总转化率均在96%以上。TEM乳胶
粒子形貌测试表明,乳胶粒子为核壳结构,且核乳液和核壳乳液平均粒径分别为101nm
和132
在合成聚丙烯酸酯乳液的基础上,采用交联法改性,将不同的交联剂与乳液共混,
考察了乳液和乳液与交联剂共混聚合物膜在不同热处理温度下物理性能之间的差异。研
究发现,脲醛树脂、三聚氯胺甲醛树脂和二羟甲尿三种交联剂的加入,能有效改善乳液
聚合物膜的耐水性和力学性能。所得乳液与交联剂共混聚合物随热处理温度升高,拉伸
强度增大、断裂伸长率降低,吸水率下降
同时,本文还以甲基丙烯酸甲酯、丙烯酸丁酯、丙烯酸羟丙酯、γ-氨基丙基三乙氧
基硅烷和甲基丙烯酸缩水甘油酯等为单体,过硫酸铵-亚硫酸氢钠氧化还原体系为引发
剂,通过种子乳液聚合法制备了核壳型有机硅的微相复合乳液。考察了引发剂的用量、
乳化剂的用量和配比、壳层软硬单体配比、有机硅用量和反应温度对乳胶粒子以及乳液
聚合物性能的影响。实验证明,以过硫酸钾和亚硫酸氢钠为引发剂,核层和壳层聚合阶
段聚合温度为60℃,乳化剂用量为单体总量的4%6%,核壳两阶段乳化剂中DSB与
CO-897质量比为2:1时,乳液及乳液聚合物性能较好。同时还发现,随着壳层单体中
硬单体用量的增加,玻璃化转变温度提高,膜拉伸强度增加,吸水率降低;随着乳化剂
用量的增加,乳胶粒子粒径减小,聚合物的吸水率升高;有机硅氧烷的加入,使得聚合
物的玻璃化转变温度、耐水性、拉伸强度提高。
关键词:丙烯酸酯甲基丙烯酸缩水甘油酯核一亮乳液交联剂有机硅
论文类型:基础研究
英文摘要
Subject: Synthesis and Characterization of Modified Acrylate Copolymer
Speciality: Applied Chemistry
Name: Nie Ying(signature)_/ul
Instructor: Liu Xiang(signature )_dd
t
ABSTRACT
Micro-phase composite latex was prepared with the monomers of methyl
methacrylate(MMA) butyl acrylate(BA) 2-ethylhexyl acrylate(EHA)and glycidyl
methacrylate(GMA), using ammonium persulfate(APS)and sodium bisulfite(HS) as redox
initiator. The latex with PMMA-BA core and PEHA-GMA shell was synthesized by two-stage
emulsion polymerization. Its particle morphology was observed by transmission electron
microscopy(TEM) It was investigated the glass transition temperature, mechanical properties
and hydroscopicity of latex copolymers which were treated by different heat treatmen
temperature. Testing results shown that the system temperature of core and shell portion
polymerization should keep at 600 and the feeding progress should finish in 40 min and 60
min each other. In this condition, the total conversion of monomers were both more than 96%
TEM results showed that the latex particle had anticipated core-shell structure and the core
and shell average particle diameter was 10 and 132 nm
After having the dried film of emulsion or emulsion mied with different crosslinking agent,
then treated them under different heat treatment temperatures and inspected their physics
property diference. Testing results shown that with the introduction of urea-formaldehyde
resin, melamine-formaldehyde resin and dimethylolureain to the PMMA-BA, the
comprehensive performance of emulsion was very well and mechanical properties was
increased. With the rise of heat treatment temperature, glass transition temperature
composite latex and composite latex membrane with crosslinking agent was heightened,
tensile strength was increased and hydroscopicity were reduced
At the same time, micro-phase composite latex was prepared with the monomers of methy
methacrylate (MM), butyl acrylate(BA), 2-hydroxypropyl acrylate(HPA), glycidyl
methacrylate(GM )and Y-aminoprop triethoxysilane, using ammonium persulfate(APS
and sodium bisu i HS)as redo initiator. The cor