Polyisoprene latex graphene composites and methods of making them

Abstract

The present invention relates to a method of preparing reduced graphene oxide, incorporation of the reduced graphene oxide into polyisoprene latex to provide a polyisoprene latex graphene composite and elastomeric articles prepared using the polyisoprene latex-graphene composite. In particular, the reduction of graphene oxide is accomplished without the use of strong reducing agents and organic solvents and incorporation of the reduced graphene oxide into polyisoprene latex is accomplished using room temperature latex mixing method or hot maturation. The resultant composite exhibits good colloid stability and polyisoprene latex films produced from the composite exhibit good mechanical properties with improved ageing resistance.

1 .- 19 . (canceled) 
     
     
         20 . A polyisoprene latex graphene composite composition comprising:
 a. polyisoprene latex;   b. at least one stabilizer;   c. at least one curing agent; and   d. reduced graphene oxide.   
     
     
         21 . The composition according to  claim 20 , wherein the at least one stabilizer comprises a metal hydroxide, an anionic surfactant, an anionic dispersant, or a combination thereof. 
     
     
         22 . The composition according to  claim 21 , wherein the at least one stabilizer comprises potassium hydroxide, sodium dodecyl sulfate, sodium salt of polymerized alkyl naphthalene sulfonic acid, or a combination thereof. 
     
     
         23 . The composition according to  claim 20 , wherein the at least one stabilizer is present in an amount of from about 0.01 to about 5.0 phr. 
     
     
         24 . The composition according to  claim 20 , wherein the at least one curing agent comprises sulfur, a dithiocarbamate, a thiazole, zinc oxide, or a mixture thereof. 
     
     
         25 . The composition according to  claim 24 , wherein the dithiocarbamate comprises zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, or a combination thereof. 
     
     
         26 . The composition according to  claim 24 , wherein the thiazole comprises zinc 2-mercaptobenzothiazole. 
     
     
         27 . The composition according to  claim 20 , wherein the at least one curing agent is present in an amount of from 0.5 to about 8.0 phr. 
     
     
         28 . The composition according to  claim 20 , further comprising an antioxidant. 
     
     
         29 . The composition according to  claim 28 , wherein the antioxidant comprises a hindered arylamine, a polymeric hindered phenol, or a reaction product of p-cresol and dicyclopentadiene. 
     
     
         30 . The composition according to  claim 28 , wherein the antioxidant is present in an amount of from 0.1 to about 3.0 phr. 
     
     
         31 . The composition according to  claim 20 , further comprising pH adjuster. 
     
     
         32 . The composition according to  claim 31 , wherein a pH of the composition is from 8.5 to 13.5. 
     
     
         33 . The composition according to  claim 20 , wherein the reduced graphene oxide is present in an amount of from 0.01 to about 1.0 phr. 
     
     
         34 . An elastomeric article formed using the composition of  claim 20 . 
     
     
         35 . The elastomeric article according to  claim 34 , wherein the elastomeric article is a condom. 
     
     
         36 . The elastomeric article according to  claim 34 , wherein the elastomeric article is a glove. 
     
     
         37 . The elastomeric article according to  claim 34 , wherein the elastomeric article is a catheter. 
     
     
         38 . The elastomeric article according to  claim 34 , wherein the elastomeric article has a thickness of between about 0.01 and about 3 mm. 
     
     
         39 . The elastomeric article according to  claim 34 , wherein the elastomeric article has a 700% modulus of between about 21 and 22 MPa when tested in accordance with ATM Test Method D412-06a (2013).