高固含量无溶剂水性聚氨酯的制备

摘要

Without any solvent, the high solid content solvent-free waterborne polyurethane( WPU) was syn-thesized using PBA or PTMG, IPDI, BDO and hydrophilic chain extender DMBA as the raw materials. The effects of DMBA content, NCO/OH molar ratio, the variety and molecular weight of soft segments on the phase inversion behavior, viscosity and the solid content of the solvent-free WPU were studied, and the molecule structure of the WPU was also characterized by carbon nuclear magnetic resonance spectra (13C-NMR). The results showed that a high solid content solvent-free waterborne polyurethane was prepared successfully when DMBA content was 3. 3%~4. 3% and NCO/OH ratio was 1. 4~1. 7. PBA was more suitable for the synthesis of high solid content solvent-free waterborne polyurethane than PTMG.%在不加任何溶剂的条件下,以二羟甲基丁酸(DMBA)作为亲水扩链剂、用异佛尔酮二异氰酸酯(IPDI)、聚己二酸丁二醇酯二醇(PBA)或聚四氢呋喃二醇(PTMG)、丁二醇(BDO)为原料,合成了高固含量无溶剂水性聚氨酯,研究了亲水扩链剂含量、异氰酸酯指数(R值)、软段种类及分子量对水性聚氨酯合成过程中的相转变及其黏度和固含量的影响,并用核磁共振碳谱(13 C-NMR)对最终合成的水性聚氨酯进行了结构分析.结果表明,DMBA含量、R值及软段的种类和分子量对体系的相转变有明显影响,DMBA质量分数在3.3%~4.3%、R值在1.4~1.7之间时,可制得高固含量、无溶剂水性聚氨酯,PBA更适合用于高固含量无溶剂水性聚氨酯的合成.