封闭剂用于非异氰酸酯预聚体扩链制备聚氨酯弹性体材料的研究

使用甲乙酮肟和苯酚分别对聚醚型聚氨酯预聚体进行封端，然后与端氨基非异氰酸酯基聚氨酯预聚体嵌段扩链，制备聚氨酯膜。分析了甲乙酮肟和苯酚的封端温度、解封温度和封端效果；分别考察了封闭剂对膜力学性能与热性能的影响。结果表明，差示扫描热量法显示苯酚和甲乙酮肟的封端反应温度分别为100 ℃和80 ℃；从封闭效果、膜的力学性能及环保角度分析比较，甲乙酮肟作聚醚型预聚体的封闭剂优于苯酚，甲乙酮肟封闭预聚体扩链后膜的拉伸强度为25.1 MPa，断裂伸长率为424 %；热重分析表明膜的热性能基本不受封闭剂种类的影响。

Study on Sealant Used in Polyurethane Elastomer Prepared by Non isocyanate Prepolymer Chain Extender

Polyether polyurethane prepolymer was capped with either methyl ethyl ketoxime and phenol, subsequently was chain extended with non isocyanate polyurethane prepolymer, which was used to prepare the membrane. The capping and de capping temperatures of methyl ethyl ketoxime and phenol, as well as their capping effect were compared. Differential scanning calorimetry determined the capping reaction temperatures of methyl ethyl ketoxime and phenol were 100 ℃ and 80 ℃ respectively. Considering the capping effect, mechanical properties of the membrane, and environmental protection, methyl ethyl ketoxime was preferred to phenol. For the membrane based on methyl ethyl ketoxime, the tensile strength was 25.1 MPa, the elongation at break was 424 %. Thermogravimetric analysis indicated that the thermal properties of the membranes were not influenced by the capping agent.