【作者】 朱华伟；

【导师】 郭文录；

【作者基本信息】 江苏科技大学 ， 应用化学， 2011， 硕士

【摘要】 本文对环氧树脂改性苯丙乳液的国内外研究现状进行了综述,通过单体预乳化法结合核壳乳液聚合工艺,制备出了稳定的环氧改性苯丙乳液,并将所得环氧改性苯丙乳液进行了结构与性能的测试和表征。主要讨论了乳化剂、引发剂、温度、软硬单体配比、环氧树脂、功能性单体等因素对乳液聚合的影响,确定了各自的最佳条件。乳化剂的最佳用量为3.5 %,其中阴离子乳化剂和非离子乳化剂的配比为1/1.5;引发剂的最佳用量为0.6 %,最佳温度范围为75～78℃;软硬单体最佳配比为1/1;采用E-44型环氧树脂,用量取10%,功能单体甲基丙烯酸和N-羟甲基丙烯酰胺的最佳用量都为2%。为了促进固化,加入了潜固化剂,确定固化条件为150℃,40 min。通过红外光谱仪对环氧改性苯丙乳液进行了表征,1251 cm^-1处的苯醚的吸收峰,915 cm^-1处的环氧基吸收峰和1726 cm^-1处羰基吸收峰,验证了环氧参与了接枝共聚。通过热重分析得到改性后乳液的热分解温度大于未改性的乳液。接触角也从34.77°增大到为63.05°。乳液粒径分布较窄,接近正态分布。同时通过交流阻抗和极化曲线的测试,发现涂层电阻提高了1个数量级,腐蚀电位提高,腐蚀电流变小。说明所制得的新型环氧改性苯丙乳液比普通苯丙乳液具有更强的憎水性,更好的热稳定性,更优异的防腐性能。另外,环氧改性苯丙乳液在耐水性、冻融稳定性和硬度等方面与未改性苯丙乳液相比也有所提高。采用该改性乳液配制的涂料,具有优异的耐水性、耐碱性、耐擦洗性和耐候性。实验确定了分散剂的最佳用量0.7 %,成膜助剂为2.0 %,流平剂为0.15 %,增稠剂为0.2 %,消泡剂为0.3 %,PVC在54 %时性能最佳。所制涂料绿色环保,综合性能优良。更多还原

【Abstract】 The study of styrene-acrylic emulsion modified by epoxy resin both at home and abroad was reviewed. The emulsion was prepared by use of pre-emulsified addition and core-shell emulsion polymerization technology. The effect of surfactants, initiator, temperature, the ratio of soft monomer and hard monomer , epoxy resin, functional monomer on modified emulsion was investigated,and the best formulation was determined. The best formulation could be obtained when the contents of surfactants was 3.5 %, the ratio of surfactants was 1/1.5, the content of initiator was 0.6 %, the best temperature was 75℃⁷8℃, the ratio of soft monomer to hard monomer was 1/1, the content of E-44 was 2%,the content of functional monomer（MAA,N-MA） was 2 %. The latent curing agent was added for promoting curing. The best cure condition was under 150℃for baking 40 min. The structure of modified emulsion was characterized by FTIR, the peaks at 915 cm^-1 and 1251 cm-1 and 1726 cm^-1 correspond respectively to the motion of epoxy, phenylate and carbonyl group. The thermal graviting analysis found that thermal decomposition temperature of modified emulsion was higher than unmodified emulsion. The contact angle was also from 34.77°to 63.05°.The distribution of emulsion particle was narrow and close to normal distribution. The ESI and polarization curve testing found that coat resistance had one order of magnitude increased, the corrosion potential had raised and the corrosion current had decreased. It proved that modified emulsion possessed better hydrophobicity, thermal stability, anticorrosive property compared to styrene-acrylic emulsion. The modified emulsion also had better waterproof ability, frost and thaw stability compared to unmodified emulsion.The coating was prepared with modified styrene-acrylic emulsion. This coating had outstanding waterproof ability, base proof ability, scrub ability and weather ability. The results showed: the best content of dispersant was 0.7 %, the content of film additive was 2.0 %, the content of leveling agent was 0.15 %, the content of bodying agent was 0.2 %, and the content of defoamer was 0.3 %. The best performance was obtained when PVC=54 %. The styrene-acrylic coating modified by epoxy resin was green and had good combination properties.更多还原