Grafted polyethylene

Abstract

Grafted polyethylene polymers and copolymers are reactively extruded to achieve enhanced rheological properties. The utilization of an oligomeric or polymeric wax in the reactive extrusion process with functionalized agents, results in improved rheological characteristics of the grafted polymer.

1 . A composition comprising a melt processable grafted polymer composition derived from the combination of:
 (i) a polyethylene or polyethylene copolymer,   (ii) an oligomeric or polymeric wax,   (iii) a functionalized agent, and   (iv) a free radical initiator.   
     
     
         2 . A composition according to  claim 1 , wherein the free radical initiator includes organic peroxides or diazo compounds. 
     
     
         3 . (canceled) 
     
     
         4 . A composition according to  claim 1  wherein the oligomeric or polymeric wax is a polyethylene wax, polypropylene wax, triglyceride wax, diglyceride wax, monoglyceride wax, fatty acid wax, fatty amide wax, metal stearates or combinations thereof. 
     
     
         5 . A composition according to  claim 1 , wherein the functionalized agent includes ethylenically unsaturated monomers having a reactive group.  
     
     
         6 . A composition according to  claim 1 , wherein the functionalized agent includes functionalized acrylates, functionalized methacrylates, functionalized styrenics, functionalized dienes, functionalized olefins, or combinations thereof. 
     
     
         7 . A composition according to  claim 1 , wherein the functionalized agent includes an electrophilic or nucleophilic reactive moiety selected from amines, amides, esters, carboxylic acids, carboxylic acid halides, anhydrides, imides, alcohols, isocyanates, oxazolines, epoxides and silanes. 
     
     
         8 . A composition according to  claim 1 , wherein the melt processable polymeric composite has a melt flow index value according to ASTM D1238 of at least a 100% greater value than a melt flow index of a corresponding grafted polyethylene or polyethylene copolymer produced in the absence of the oligomeric or polymeric wax. 
     
     
         9 . The composition according to  claim 1 , wherein the melt processable grafted polymer composition comprises a grafted polyethylene or polyethylene copolymer. 
     
     
         10 . (canceled) 
     
     
         11 . A method of producing the composition according to  claim 1  comprising melt processing a polyolefin or polyolefin copolymer with an oligomeric or polymeric wax, maleic anhydride, and a free radical initiator to form a grafted polyethylene polymer or polyethylene copolymer. 
     
     
         12 - 13 . (canceled)  
     
     
         14 . A melt processable, grafted polymer composition formed by melt processing a mixture comprising (a) polyethylene and/or polyethylene copolymer; (b) oligomeric and/or polymeric wax having a weight average molecular weight of less than 50,000 g/mol; (c) functionalized agent, which includes an ethylenically unsaturated monomer having a reactive group; and (d) free radical initiator. 
     
     
         15 . The composition of  claim 14 , wherein the reactive group is a carboxylic acid and/or carboxylic anhydride. 
     
     
         16 . The composition of  claim 14 , wherein the functionalized agent includes maleic anhydride. 
     
     
         17 . The composition of  claim 14 , wherein the mixture comprises high density polyethylene, low density polyethylene and/or linear low density polyethylene. 
     
     
         18 . The composition of  claim 14 , wherein the oligomeric and/or polymeric wax has a weight average molecular weight of less than 10,000 g/mol and comprises polyethylene wax, polypropylene wax, triglyceride wax, diglyceride wax, monoglyceride wax, fatty acid wax, and/or fatty amide wax. 
     
     
         19 . The composition of  claim 14 , wherein the mixture comprises high density polyethylene resin (HDPE), polyethylene wax, and maleic anhydride. 
     
     
         20 . The composition of  claim 14 , wherein the mixture comprises about 20 to 90 wt. % of the polyethylene and/or polyethylene copolymer; about 1 to 80 wt. % of the oligomeric or polymeric wax; and about 1 to 10 wt. % of the functionalized agent. 
     
     
         21 . The composition of  claim 14 , wherein the mixture comprises about 20 to 90 wt. % high density polyethylene resin; about 1 to 80 wt. % polyethylene wax; and about 0.5 to 5 wt. % maleic anhydride.  
     
     
         22 . The composition of  claim 21 , wherein the melt processable, grafted polymer composition has a melt flow index value according to ASTM D1238 of at least a 100% greater value than a melt flow index of a corresponding grafted polyethylene produced in an absence of the oligomeric or polymeric wax. 
     
     
         23 . A melt processable, grafted polymer composition formed by melt processing a mixture comprising (a) polyethylene; (b) oligomeric and/or polymeric wax having a weight average molecular weight of less than 50,000 g/mol; (c) an ethylenically unsaturated monomer having a reactive group; and (d) free radical initiator;
 wherein the oligomeric and/or polymeric wax comprises polyethylene wax, polypropylene wax, triglyceride wax, diglyceride wax, monoglyceride wax, fatty acid wax, and/or fatty amide wax.   
     
     
         24 . The composition of  claim 23 , wherein the mixture comprises about 20 to 90 wt. % of the polyethylene, which includes high density polyethylene; about 1 to 80 wt. % of the oligomeric and/or polymeric wax, which includes the polyethylene wax; and about 0.5 to 5 wt. % of the ethylenically unsaturated monomer, which includes maleic anhydride. 
     
     
         25 . The composition of  claim 1 , wherein the combination comprises about 20 to 90 wt. % of the polyethylene or polyethylene copolymer; about 1 to 80 wt. % of the oligomeric and/or polymeric wax; and about 0.5 to 5 wt. % of the functionalized agent;
 wherein the polyethylene or polyethylene copolymer includes high density polyethylene; the oligomeric or polymeric wax has a weight average molecular weight of less than 10,000 g/mol and includes polyethylene wax; the functionalized agent includes maleic anhydride; and   the melt processable grafted polymer composition has a melt flow index value according to ASTM D1238 of at least a 100% greater value than a melt flow index of a corresponding grafted polyethylene or polyethylene copolymer produced in the absence of the oligomeric or polymeric wax.