三元聚羧酸分散剂的合成及其在建筑涂料中的应用

Synthesis of Ternary Polycarboxylic Acid Dispersant and Its Application in Architectural Coatings

摘要:

建筑水性涂料分散剂在分散效率和耐水性能上存在矛盾。以烯烃类单体烯丙基聚氧乙烯醚（APEG-2400）、甲基丙烯酸（MAA）、苯乙烯磺酸钠（SSS）或烯丙基磺酸钠（SAS）及分子量调节剂异丙醇（IPA）为原料，过硫酸铵（APS）做引发剂，按不同比例聚合得到新型系列的水性涂料用三元聚羧酸分散剂。同时，研究磺酸单体在不同种类、比例下对分散剂的分散性和耐水性的影响，并得到该体系下较优的配比。合成分散剂的结构采用FT-IR和¹H NMR进行表征，相对分子质量及其分布、表面张力等则分别采用凝胶渗透色谱仪和表面张力仪进行表征。探讨不同磺酸基团的组成、比例及整体分子量对粉料的分散性能和涂料应用性能的影响。结果表明：烯丙基聚氧乙烯醚-甲基丙烯酸-苯乙烯磺酸钠三元体系下（n（APEG-2400）∶n（MAA）∶n（SSS）∶n（IPA）∶n（APS）=1∶4∶10∶1∶1.05），在75 ℃下滴加反应150 min，所得样品分散效果较佳；数均分子量在18 000左右的所得分散剂具有相对适中的表面张力（23.9 mN?m^-1），对应所得的涂料具有更好的热储稳定性和耐水刷性（大于1500次）。

Abstract:

Good dispersion efficiency and high water-resistance of the dispersant agent were hard to simultaneously obtain in water-based architectural coatings. In this study， olefin monomers such as allyl polyoxyethylene ether （APEG-2400）， methacrylic acid （MAA）， sodium styrene sulfonate （SSS） / sodium allyl sulfonate （SAS） and molecular weight regulator isopropyl alcohol （IPA） were used for the polymerization of ternary polycarboxylic acid dispersants in different proportions. Effects of different sulfonic acid monomers on dispersion properties in different types and proportions ternary compound dispersant system were studied in water-base coatings. The functional groups were characterized by FTIR and ¹H NMR. The relative molecular weight & distribution， surface tension and other metrics were characterized by gel permeation chromatograph and surface tensimeter， respectively. The effects of the composition， proportion and overall molecular weight of different sulfonic acid groups on the dispersion properties of powder and coating application were discussed. The ideal dispersant was obtained by the suitable reaction condition：n（APEG-2400） ∶n（MAA） ∶n（SSS） ∶n（IPA） ∶n（APS）=1∶4∶10∶0.75∶1.05， 75 ℃ reaction temperature， 150 min of reaction time for dropping. It showed an ideal dispersing performance by the suitable surface tension （18.2 mN?m^-1）， compatible number average molecular weight （18 000）， good heat stability and ideal scrubbing resistance （>1500 times）.