SHAPE MEMORY POLYMER AND RESIN COMPOSITION THEREOF

1 . A shape memory polymer comprising a polymer blend of a polyvinyl chloride and a polyurethane, the polyurethane being prepared from a reaction mixture consisting essentially of:

(A) at least one diisocyanate compound; and

(B) a long chain polyol, with molecular weight from 500 to 5000, is present in an amount more than 80 weight percent of the polyurethane, and the functionality of the long chain polyol ranges from 2 to 3;

wherein the polyvinyl chloride is configured to be the hard segment that preserves the original shape, and the polyurethane is configured to be the soft segment that forms the temporary shape.

2 . The shape memory polymer of claim 1 , wherein the long chain polyol is present in an amount more than 90 weight percent of the polyurethane.

3 . The shape memory polymer of claim 1 , wherein the reaction mixture is substantially free of chain extender.

4 . The shape memory polymer of claim 3 , wherein the chain extender is present in an amount less than 5 weight percent of the reaction mixture.

5 . The shape memory polymer of claim 1 , wherein the functionality of the long chain long chain polyol is 2.

6 . The shape memory polymer of claim 1 , wherein the long chain polyol is polyester polyol or polyester diol.

7 . The shape memory polymer of claim 1 , wherein the long chain polyol is polycaprolactone (PCL).

8 . The shape memory polymer of claim 1 , wherein the molar ratio of all diisocyanate compounds to the long chain polyol is between 0.9 to 1.2.

9 . The shape memory polymer of claim 1 , wherein the weight ratio of the polyurethane to the polyvinyl chloride is equal to or more than 100/100.

10 . The shape memory polymer of claim 1 , wherein the molecular weight of the polyvinyl chloride ranges from 40,000 to 150,000.

11 . The shape memory polymer of claim 1 , wherein the polymer blend comprises an amorphous polyvinyl chloride and a semi-crystalline polyurethane.

12 . The shape memory polymer of claim 1 , wherein the hard segments and the soft segments also possess the function to fix the temporary shape of the shape memory polymer at temperatures below a transition temperature.

13 . The shape memory polymer of claim 12 , wherein the shape memory polymer comprises one of the following properties:

(1) the transition temperature ranges from 30 to 50 degrees Celsius;

(2) the transition temperature greater than 40 degrees Celsius;

(3) if the appliance is a toy, a transition temperature of 40 to 50 degrees Celsius;

(4) a tensile storage modulus more than 100 MPa at 20 degrees Celsius;

(5) a tensile storage modulus more than 1 MPa at 45 degrees Celsius;

(6) the shape fixity equal to or more than 80 percent.

14 . A composite resin composition for fabricating the shape memory polymer of claim 1 , containing:

(A) polyvinyl chloride particles made from the polyvinyl chloride of claim 1 ; and

(B) polyurethane particles made from the polyurethane of claim 1 .

15 . The resin composition of claim 14 , wherein the particle diameter of polyvinyl chloride particles and polyurethane particles ranges from 0.5 to 8.0 mm.

16 . The resin composition of claim 14 , wherein the resin composition further containing plasticizers and nucleation agents.

17 . The resin composition of claim 14 , wherein the shape memory polymer is fabricated from the resin composition by extrusion, injection molding, casting, compression molding, blow-molding, rotational molding, rapid prototyping, solid freeform fabrication, or combinations thereof.

18 . The resin composition of claim 17 , wherein the shape memory polymer is fabricated by injection molding, with an operation pressure of 40 to 100 bar and an operation temperature of 100 to 200 degrees Celsius.

19 . The resin composition of claim 18 , after the injection molding, the fabricated shape memory polymer is further processed with radiation of 10˜100 kGy for crosslinking.

20 . The resin composition of claim 19 , wherein the radiation includes electron beam, gamma ray or X-ray.