SHAPE MEMORY POLYURETHANE COMPOSITION AND LAMINATE USING THE SAME
The present invention provides a shape memory polyurethane composition and laminate using the same. The shape memory polyurethane composition at least comprises a polyurethane synthesized by polymerization of at least a polyol having at least two functional groups, a diisocyanate having at least two functional groups and a chain extender having at least two functional groups wherein the molar ratio of the diisocyanate:polyol:chain extender is 2˜3:1:1˜2, the NCO/OH molar ratio is 0.95˜1.1, the weight average molecular weight is 50,000˜300,000, the polyurethane has a first phase transition temperature being in the range of 40° C.˜60° C. and the storage elastic modulus at the temperature less than or equal to the first phase transition temperature is more than or equal to 10 9 Pa.
1 . A laminate, comprising a base fabric and a shape memory polymer layer;
wherein the shape memory polymer layer is formed by a shape memory polyurethane composition;
the shape memory polyurethane composition at least comprises: a polyurethane synthesized by polymerization of at least a polyol having at least two functional groups, a diisocyanate having at least two functional groups and a chain extender having at least two functional groups;
the molar ratio of the diisocyanate:polyol:chain extender is 2˜3:1:1˜2, the NCO/OH molar ratio is 0.95˜1.1, the weight average molecular weight is 50,000˜300,000, the polyurethane has a first phase transition temperature being within 40° C.˜60° C., the storage elastic modulus at the temperature less than or equal to the first phase transition temperature is more than or equal to 10 9 Pa, and the storage elastic modulus at the temperature above (the first phase transition temperature+10° C.) is between 10 6 Pa and 10 8 Pa.
2 . The laminate as claimed in claim 1 , wherein the base fabric is a three-dimensional fabric having two surface layers and a middle layer between the two surface layers and the three-dimensional fabric has air permeability of more than 50 cfm according to ASTM D737.
3 . The laminate as claimed in claim 1 , wherein the shape memory polymer layer is formed into a continuous film on a portion of the base fabric.
4 . The laminate as claimed in claim 2 , wherein the laminate is formed in to a bra shape and the shape memory polymer layer is formed into a continuous film on a portion of the base fabric.
5 . The laminate as claimed in claim 1 , wherein the shape memory polymer layer is formed into a randomly-fractured film on a portion of the base fabric and the laminate has air permeability of more than 50 cfm according to ASTM D737.
6 . The laminate as claimed in claim 2 , wherein the laminate is formed in to a bra shape and the shape memory polymer layer is formed into a randomly-fractured film on a portion of the base fabric and the laminate has air permeability of more than 50 cfm according to ASTM D737.
7 . The laminate as claimed in claim 1 , wherein the polyol is a polyol containing a carbonate moiety and has a weight average molecular weight of 1000˜3000 and the polyurethane has a weight average molecular weight of 80,000˜120,000.
8 . The laminate as claimed in claim 1 , wherein the laminate has hardness more than 50D according ASTM D2240 type D scale.
9 . The laminate as claimed in claim 5 , wherein the laminate is water repellent.
10 . The laminate as claimed in claim 6 , wherein the laminate further comprises a supporting layer on a portion of the base fabric.
11 . A shape memory polyurethane composition, at least comprising: a polyurethane synthesized by polymerization of at least a polyol having at least two functional groups, a diisocyanate having at least two functional groups and a chain extender having at least two functional groups;
wherein the molar ratio of the diisocyanate:polyol:chain extender is 2˜3:1:1˜2, the NCO/OH molar ratio is 0.95˜1.1, the weight average molecular weight of the polyurethane is within 50,000˜300,000, the polyurethane has a first phase transition temperature being within 40° C.˜60° C., the storage elastic modulus at the temperature less than or equal to the first phase transition temperature is more than or equal to 10 9 Pa and the storage elastic modulus at the temperature above (the first phase transition temperature+10° C.) is between 10 6 Pa and 10 8 Pa.
12 . The shape memory polyurethane composition as claimed in claim 11 , further comprising a solvent wherein the solvent can dissolve the polyurethane in the shape memory polyurethane composition and the shape memory polyurethane composition comprises 20˜40% in weight of the polyurethane.
13 . The shape memory polyurethane composition as claimed in claim 11 , wherein the polyol is a polyol containing a carbonate moiety and has a weight average molecular weight of 1000˜3000, the NCO/OH molar ratio is 0.95˜1.06, the molar ratio of the diisocyanate:polyol:chain extender is 2:1:1.
14 . The shape memory polyurethane composition as claimed in claim 12 , wherein the polyol is a polyol containing a carbonate moiety and has a weight average molecular weight of 1000˜3000, the NCO/OH molar ratio is 0.95˜1.06, the molar ratio of the diisocyanate:polyol:chain extender is 2:1:1.
15 . The shape memory polyurethane composition as claimed in claim 11 , wherein the polyurethane is processed by annealing at 80˜100° C. for 20˜24 hours.