	US 7,371,799 B2
	Blends of amorphous and semicrystalline polymers having shape memory properties
Patrick T. Mather, Chagrin Falls, Ohio (US); Changdeng Liu, Storrs, Conn. (US); and Cheryl J. Campo, Cleveland Heights, Ohio (US)
Assigned to University of Connecticut, Farmington, Conn. (US)
Filed on Jan. 19, 2007, as Appl. No. 11/624,952.
Application 11/624952 is a division of application No. 10/683558, filed on Oct. 10, 2003, granted, now 7,208,550.
Claims priority of provisional application 60/418023, filed on Oct. 11, 2002.
Claims priority of provisional application 60/466401, filed on Apr. 29, 2003.
Claims priority of provisional application 60/488323, filed on Jul. 18, 2003.
Prior Publication US 2007/0135578 A1, Jun. 14, 2007
Int. Cl. C08L 23/04 (2006.01); C08L 27/04 (2006.01); C08L 27/06 (2006.01); C08L 27/16 (2006.01); C08L 33/04 (2006.01); C08L 33/10 (2006.01); C08L 35/02 (2006.01)

U.S. Cl. 525—199 [525/222; 525/239; 525/240]

4 Claims

1. Method of preparing a shape memory polymer material characterized by a T_gexceeding room temperature whose rubber modulus and elasticity is derived substantially from physical crosslinking comprising

melt blending

a crystalline polymer selected from the group consisting of

poly(vinylidene fluoride), polylactide, poly(hydroxybutyrate),

poly(ethylene glycol), polyethylene, poly(ethylene-co-vinyl acetate),

poly(vinyl chloride), poly(vinylidene chloride), and copolymers of

vinylidene chloride and vinyl chloride with

an amorphous polymer selected from the group consisting of poly(vinyl

acetate), poly(methyl acrylate), poly(ethyl acrylate), and atactic

poly(methyl methacrylate)

at a temperature of 10˜20° C. above the melting temperature of the crystalline polymers, for a time sufficient to ensure good mixing,

cooling the resultant blend to room temperature,

introducing said blend into a press maintained at about 180° C.,

applying pressure to said blend, and then

rapidly cooling the film thereby formed to an annealing temperature T_g<T_a<T_m, where it is held until crystallization is complete and following which the film is cooled to room temperature.