苯乙烯-对乙烯基苯磺酸钠乳液共聚物的研究

Copolymers Prepared by Emulsion Copolymerization of Styrene and Sodium Styrene Sulfonate

在十二烷基硫酸钠、十二烷基联苯醚二磺酸钠及辛基苯酚聚氧乙烯醚所组成的阴离子/非离子复合乳化剂存在下,用批量聚合法和半连续聚合法制备了苯乙烯(St)-对乙烯基苯磺酸钠(NaSS)二元乳液共聚物,用动态激光光散射法研究了乳胶粒的粒径与聚合工艺及NaSS加入量的关系.依次以甲醇和水为溶剂,利用索氏提取器对共聚物试样进行纯化,并利用傅里叶变换红外光谱和元素分析法对提纯后的共聚物试样进行结构及组成分析.实验结果表明,当NaSS的摩尔分数为5%～20%时,乳胶粒的粒径随NaSS加入量的增加而增大.随NaSS加入量的增加,批量聚合法共聚物中NaSS单元的含量变化较小,半连续法共聚物中NaSS单元的含量则增加.

Two series of latex copolymers were prepared separately by batch and semicontinuous emulsion copolymerization of styrene (St) and sodium styrene sulfonate (NaSS) in the presence of anion/nonionic complex emulsifier which was composed of sodium dodecyl sulfate (SDS), sodium dodecyl biphenylate disulfate (SDBDS) and polyoxyethylene (10) octylphenyl ether (OP-10). Dynamic laser light scattering technique was performed to determine average diameter and polydispersity of the latex particles. Dried colloid samples were extracted by methanol and sequentially by water successively to remove low relative molecular mass material and water soluble polymers. Existence of NaSS units in purified polymers was measured by means of FTIR and sulfur element analysis. Latex particles size increased along with mole fraction of NaSS added in starting material within 5%-20% in both processes. While mole fraction of NaSS added in starting material increased, the NaSS units content in copolymers changed little in batch process, but increased correspondingly in semicontinuous process. Functional groups content of copolymers in semicontinuous process was higher than that in batch process.