高耐水性纳米水性聚氨酯的合成与表征

Synthesis and characterization of waterborne polyurethane nano-emulsion with good water-resistance

以异佛尔酮二异氰酸酯（IPDI）、聚丙二醇（PPG）、二羟甲基丙酸（DMPA）、1,4-丁二醇（BDO）为主要原料,采用预聚体分散法制备了系列水性聚氨酯（WPU）乳液,考察了多种工艺因素条件对聚氨酯乳液粒径及分布的影响,同时观测到未改性水性聚氨酯纳米乳液涂层耐水性极差。在相转变过程中加入含氨基的硅烷偶联剂作为后交联剂,研究结果表明,后交联剂的加入可以有效降低乳液的粒径,同时提高涂层的耐水性及表面疏水性,该方法可以获得粒径介于20~30nm的成膜耐水性佳的水性聚氨酯。同时,讨论了含氨基硅烷偶联剂作为后交联剂使水性聚氨酯乳液粒径减小的机理。

A series of waterborne polyurethane （WPU） on the average particle size and size distribution were discussed. dispersions were prepared and the effect of various factors It was discovered that unmodified WPU nano-emulsion had high water swelling, indicating its bad water resistance. Silane coupling agent was then added to the system during the e- mulsion process, it was found out that silane coupling agent had a positive effect on decreasing WPU dispersions particle size, improving WPU films water resistance and hydrophobicity, WPU nano-emulsion with particle size between 20~ 30nm and had good water-resistance of its film was successfully synthesized. Furthermore, the mechanism of size decrea- sing was discussed.