硅烷改性水性聚氨酯分散液的合成与性能研究

Study on Synthesis and Properties of Silane Modified Waterborne Polyurethane Dispersion

以二羟甲基丙酸(DMPA)为亲水单体,甲苯二异氰酸酯(TDI)、聚醚二元醇(N210)为原料,丁二醇为扩链剂,三乙胺(TEA)为中和剂合成水性聚氨酯。采用有机硅烷对水性聚氨酯进行改性,研究了有机硅烷、亲水单体的用量对改性水性聚氨酯外观稳定性及涂膜性能的影响。结果表明:适量的有机硅烷的引入可以有效改善水性聚氨酯的耐水性、附着力以及硬度。当硅烷加入量为0.6%,改性水性聚氨酯的吸水率为5.5%,为未改性水性聚氨酯膜吸水率的1/6。

The title waterborne polyurethane （WPU） was prepared from dimethylol propionic acid - （DMPA） as hydrophilic monomer, toluene -2, 4 -diisocyanate （TDI） ,polyols N210 as raw materials, triethylamine（TEA） as neutralizing reagent and butylene glycol as chainextender. The modification of waterborne PU was carried through introducing silane into PU molecular chain. The effect of silane content and extender agent and DMPA content on the apparent and stability of WPU modified by silane was studied. The results showed that the water resistance and the hardness and the adhesion of modified WPU were improved. When the content of silane was 0. 6%, the water - absorption of modified WPU was 5.5% , which was one sixth if compared with unmodified WPU.