Polyurethane with shape memory property, composition containing it and shape memory fabric prepared therefrom

Abstract

The said polyurethane is prepared through preparing polymer with diisocyanate, hydroxyl-containing oligomer, chain expander with active hydrogen radical and chain expander with carboxylic radical, neutralizer with alkali radical, blocking agent, cross-linking agent and optional catalyst in certain proportion; and subsequent reaction in water to obtain polymer. The polyurethane features the blocking diisocyanate radical and hydroxyl radical and thus shape converting temperature of -30 degree c to 100 degree c. In temperature higher than the shape converting temperature, the polyurethane may have its shape converted; in temperature lower than the shape converting temperature, the polyurethane is unchanged in shape; and the polyurethane heated to the temperature higher than the shape converting temperature will restore original shape. 本发明涉及具有形状记忆性的聚氨酯、水性形状记忆聚氨酯组合物及其制备方法、形状记忆织物及其制备方法。所述聚氨酯为将下列组分反应制备的预聚物在水中继续反应所得到的聚合物：二异氰酸酯；含羟基低聚物；含有活泼的氢基团的扩链剂和含羧基的扩链剂；含有碱性基团的中和剂；封端剂；交联剂以及任选的催化剂，其摩尔比为二异氰酸酯：含羟基低聚物：扩链剂：中和剂：封端剂：交联剂：催化剂＝0.8～1.6∶0.2～0.8∶0.4～1∶0.2～0.6∶0～1.2∶0～0.4∶0～0.02其特征在于所述聚氨酯以不同摩尔数量的异氰酸根和羟基(NCO/OH＝0.8～1.6)封端，所述聚氨酯具有在-30～100℃范围内的形状转变温度，当该聚氨酯高于所述形状记忆转变温度时会改变形状，并在冷却至低于该温度时定型，然后在加热到高于该温度时能恢复原始形状。