Shape memory polymers based on semicrystalline thermoplastic polyurethanes bearing nanostructured hard segments

Abstract

Thermoplastic polyurethanes having an alternating sequence of hard and soft segments in which a nanostructured polyhedral oligosilsesquioxane diol is used as a chain extender to form a crystalline hard segment constituting SMPs. The polyurethanes are formed by reacting a polyol, a chain extender dihydroxyl-terminated polyhedral oligosilsesquioxane and a diisocyanate. The polyurethanes have multiple applications including for example, implants for human health care, drug delivery matrices, superabsorbant hydrogels, coatings, adhesives, temperature and moisture sensors, etc.

1 - 19 . (canceled) 
     
     
         20 . A method for making a thermoplastic polyurethane shape memory polymer comprising reacting (A) a polyol, (B) a polyhedral oligosilsesquioxane diol, and (C) a diisocyanate; wherein the shape memory polymer exhibits a thermal triggering temperature of 30° C. to 60° C. 
     
     
         21 . The method of  claim 20  wherein the polyhedral oligosilsesquioxane diol is a member selected from the group consisting of 2-ethyl-2-[3-[[(heptacyclopentylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxanyl)oxy]dimethylsilyl]-propoxy]methyl]-1,3-propanediol, 2-ethyl-2-[3-[[(heptacyclohexylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxanyl)oxy]dimethylsilyl]-propoxy]methyl]-1,3-propanediol, 2-ethyl-2-[3-[[(heptaisobutylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxanyl)oxy]dimethylsilyl]-propoxy]methyl]-1,3-propanediol, 1-(2-trans-cyclohexanediol)ethyl-3,5,7,9,11,13,15-cyclohexanepentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxane, and 1-(2-trans-cyclohexanediol)ethyl-3,5,7,9,11,13,15-isobutylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxane. 
     
     
         22 . The method of  claim 20  wherein the diisocyanate is a member selected from the group consisting of 4,4′-diphenyl methylene diisocyanate (MDI), toluene-2,4-diisocyanate (TDI), toluene-2,6-diisocyanate, hexamethylene-1,6-diisocyanate (HDI), isophorone diisocyanate (IPDI), and hydrogenated 4,4′-diphenylmethane diisocyanate (H12MDI). 
     
     
         23 . The method of  claim 20  wherein the diisocyanate is 4,4′-diphenyl methylene diisocyanate. 
     
     
         24 . The method of  claim 20 , wherein the thermoplastic polyurethane shape memory polymer exhibits a thermal triggering temperature of 37° C. to 50° C. 
     
     
         25 . The method of  claim 20 , wherein the polyol is a member selected from the group consisting of polyethylene glycol (PEG), polycaprolactone (PCL) diol, polycyclooctene diol, polynorbornene diol and polymethacrylate copolymer. 
     
     
         26 . The method of  claim 20 , wherein the polyol is a member selected from the group consisting of polyethylene glycol, polycaprolactone diol, and polycyclooctene diol, and is semicrystalline. 
     
     
         27 . The method of  claim 20 , wherein the polyol is an amorphous diol having a T g  in the range of 20 to 80° C., and is a member selected from the group consisting of polynorbornene diol and polymethacrylate copolymer diol. 
     
     
         28 . A method for making a thermoplastic polyurethane polymer comprising reacting (A) a polyol, (B) a polyhedral oligosilsesquioxane diol, and (C) a diisocyanate, wherein the polyol is a member selected from the group consisting of polyethylene glycol, polycaprolactone diol, and polycyclooctene diol; wherein the polyhedral oligosilsesquioxane diol is a member selected from the group consisting of 2-ethyl-2-[3-[[(heptacyclopentylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxanyl)oxy]dimethylsilyl]-propoxy]methyl]-1,3-propanediol, 2-ethyl-2-[3-[[(heptacyclohexylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxanyl)oxy]dimethylsilyl]-propoxy]methyl]-1,3-propanediol, 2-ethyl-2-[3-[[(heptaisobutylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxanyl)oxy]dimethylsilyl]-propoxy]methyl]-1,3-propanediol, 1-(2-trans-cyclohexanediol)ethyl-3,5,7,9,11,13,15-cyclohexanepentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxane, and 1-(2-trans-cyclohexanediol)ethyl-3,5,7,9,11,13,15-isobutylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxane; and wherein the diisocyanate is 4,4′-diphenyl methylene diisocyanate. 
     
     
         29 . The method of  claim 28  wherein said reaction is carried out in presence of dibutyltin dilaurate as catalyst. 
     
     
         30 . The method of  claim 20 , wherein the polyol is polyethylene glycol, wherein the polyhedral oligosilsesquioxane is 1-(2-trans-cyclohexanediol)ethyl-3,5,7,9,11,13,15-isobutylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxane, and wherein the diisocyanate is 4,4′-diphenyl methylene diisocyanate. 
     
     
         31 . The method of  claim 20 , wherein the polyol is polycyclooctene diol, wherein the polyhedral oligosilsesquioxane diol is 2-ethyl-2-[3-[[(heptaisobutylpentacyclo-[9.5.1.1 3,9 .1 5,15 .1 7,13 ]octasiloxanyl)oxy]dimethylsilyl]-propoxy]methyl]-1,3-propanediol, and wherein the diisocyanate is 4,4′-diphenyl methylene diisocyanate. 
     
     
         32 . A thermoplastic polyurethane polymer prepared by the method of  claim 20 . 
     
     
         33 . A thermoplastic polyurethane polymer prepared by the method of  claim 28 . 
     
     
         34 . A thermoplastic polyurethane polymer prepared by the method of  claim 30 . 
     
     
         35 . A thermoplastic polyurethane polymer prepared by the method of  claim 31 . 
     
     
         36 . A composition comprising
 a thermoplastic polyurethane shape memory polymer prepared according to the method of  claim 20 , and   a filler selected from the group consisting of boron nitride, silica, titanium dioxide, montmorillonite, clay, staple, aluminum nitride, barium subcarbonate, and bismuth subcarbonate.   
     
     
         37 . The thermoplastic polyurethane shape memory polymer of  claim 36 , wherein the thermoplastic shape memory polymer exhibits a thermal triggering temperature of 37° C. to 50° C. 
     
     
         38 . A thermoplastic polyurethane polymer having the formula 
       
         
           
           
               
               
           
         
       
       wherein R is an alkyl group having six or fewer carbon atoms; wherein the ratio of x to y is 1:1 to 20:1; wherein the polyol degree of polymerization, n, is 1 to 1000; and wherein the total degree of polymerization, m, is 2 to 100. 
     
     
         39 . The thermoplastic polyurethane polymer of  claim 38 , wherein R is an alkyl group having 4 to 6 carbon atoms. 
     
     
         40 . The thermoplastic polyurethane polymer of  claim 38 , wherein R is isobutyl, cyclopentyl, or cyclohexyl.