甲壳质衍生物共混改性水性聚氨酯

Blending modification of water-based polyurethane with chitosan derivatives

采用聚酯218、聚醚310、IPDI、DMBA为主要原料合成水性聚氨酯(WPU),将一系列质量浓度梯度的壳聚糖(CS)或壳寡糖(COS)与WPU乳液共混。结果表明:由于CS相对分子质量过大,即使调整CS溶液、WPU乳液的质量浓度及pH,两者均无法稳定共混。但采用聚合度较低的COS与WPU共混可获得稳定乳液,经探究可知COS溶液的临界质量浓度为0.4 mg/mL,与WPU乳液共混的临界质量比为2∶8。测试结果表明共混改性后混合乳液的粒径、抗菌性、耐水性有所提升,对乳液稳定性及胶膜的热稳定性几乎无影响。

Polyester 218,polyether 310,IPDI,DMBA were used as the main raw materials to synthesize water-based polyurethane,and a series of mass concentration gradient chitosan(CS)or chitooligosaccharide(COS)were blended with water-based polyurethane(WPU)emulsion,the experimental results showed that because the relative molecular mass of CS was too large,even if the concentration and pH value of CS solu-tion and WPU emulsion were adjusted,the two cannot be blended stably.However,a stable emulsion could be obtained by blending COS with a lower degree of polymerization and WPU.After investigation,it could be known that the critical mass concentration of COS solution was 0.4 mg/mL,and the critical mass ratio of COS to WPU emulsion was 2∶8.The test results showed that the particle size,antibacterial property and water re-sistance of the mixed emulsion were improved after blending and modification,and it had almost no effect on the stability of the emulsion and the thermal stability of the film.