水性聚氨酯防水透湿涂层剂的合成与性能

以合适结构和分子质量的聚酯和聚醚混合二元醇、异佛尔酮二异氰酸酯(IPDI)、二羟甲基丙酸(DMPA)、1,4-丁二醇(BDO)为主要原料,三乙胺(TEA)为中和剂,合成水性聚氨酯防水透湿涂层剂乳液。讨论了R值(反应物中—NCO基团与预聚反应中所有—OH基团的摩尔分数比)对乳液稳定性和薄膜力学性能的影响,及R值、软段中聚酯和聚醚配比对织物防水透湿性能的影响。优化的防水透湿型聚氨酯涂层剂乳液的合成工艺为:聚己二酸丁二醇酯二醇(PBA)/聚乙二醇(PEG)混合多元醇(n_(PBA):n_(PEG)=2:1)为软段组分,DMPA 3.6%,与IPDI进行预聚(R=1.4),然后用1,4-丁二醇100%扩链,三乙胺中和。经聚氨酯乳液涂层的织物的透湿量可达4 736.5 g/(m~2×24 h),静水压可达6.67 kPa,可满足服用要求。

Synthesis and properties of waterproof and vapor-permeable waterborne polyurethane

Waterproof and moisture permeable waterborne polyurethane was synthesized using polyethylene glycol and polyester glycols with proper structure and molecular weight, isophorone diisocyanate (IPDI), dimethylolpropionic acid(DMPA) and 1,4-butanediol(BDO) as main materials and triethylamine (TEA) as neutralizer. Influence of R value (mole ratio of group NCO to --OH in the reactant) on stability of the solution and mechanical properties of the polyurethane membrane was discussed, as well as effects of R value and mole ratio of polyethylene glycol to polyester glycols in soft segment on coating results. The optimum synthesis process was as follows: mixed glycol of poly(1,4-butylene adipate) (PBA) and polyethylene glycol(PEG) (n_(PBA): n_(PEG) =2 : 1) as soft segment, DMPA 3.6% ,pre-polymerizing with IPDI(R = 1.4), chain extending with BDO and neutralizing with TEA. The coatings could meet wearing requirement with moisture transmission 4 736.5 g/(m~2·24 h) and hydrostatic pressure 6.67 kPa.