无溶剂合成革用有机硅改性聚氨酯的性能研究

Study on performance of organo-siloxane modified polyurethane for solvent-free synthetic leather

采用4种不同结构的有机硅氧烷改性异氰酸酯得到聚氨酯预聚体,作为制备无溶剂合成革面层的B组分。探讨了有机硅改性聚氨酯预聚体对无溶剂合成革面层及成品革的性能影响。结果表明:与未改性的相比,有机硅改性的无溶剂合成革面层,拉伸强度从5.73 MPa增加至7.82 MPa,断裂伸长率从342%增加至472%,吸水率从8.05%降低至3.36%,面层的热稳定性得到提高;制备的成品革柔软度从8.16提高至10.57,TaberH–221 000 g耐磨从856转增加至1 426转,合成革的剥离强度保留率有所增加。当采用PDMS–2改性得到的聚氨酯预聚体,其制备的无溶剂合成革综合性能较佳。

The polyurethane prepolymers were prepared with isocyanates modified separately by four kinds of different structural organo-siloxanes, and said prepolymers were used as B component for preparing the surface layers of the solvent-free synthetic leathers. The influence of the organo-siloxane modified polyurethane prepolymers on the performance of the surface layers of the solvent-free synthetic leathers and the finished leathers was discussed. The results show that compared with the surface layer without modification, the tensile strength of the organo-siloxane modified solvent-free synthetic leather surface layer increases from 5.73 MPa to 7.82 MPa, the elongation at break increases from 342% to 472%, the water absorption rate reduces from 8.05% to 3.36%, and the thermal stability of the surface layer improves. The softness of the prepared finished leathers increases from 8.16 to 10.57, the Taber H-22 1000 g abrasion resistance increases from 856 r to 1 426 r, and the peel strength retention rate of the synthetic leather slightly increases. When the polyurethane prepolymer modified by PDMS-2 was used, the prepared solventfree synthetic leather possesses better comprehensive performance.