Polymer-linked asphalt compositions
View Patent ↗Disclosed are a thermoplastic polymer-linked-asphalt composition and a process for making a thermoplastic polymer-linked-asphalt. More particularly, the present invention relates to the reaction and resultant linking of a combination of epoxide-containing polymers and anhydride-containing polymers to asphalt to form a polymer-linked-asphalt composition having higher softening points. The improved polymer-linked-asphalt product is particularly useful in roofing applications.
1. A polymer-linked-asphalt composition derived from treating asphalt with a reactant epoxy-containing ethylene copolymer and a reactant polystyrene-maleic anhydride copolymer wherein the cumulative polymer content of said polymer-linked-asphalt composition is from 0.05 to 20 weight percent relative to the total weight of polymers and asphalt.
2. The composition of claim 1 wherein said reactant epoxy-containing ethylene copolymer is a glycidyl-containing polymer.
3. The composition of claim 2 wherein said reactant glycidyl-containing ethylene copolymer is a copolymer represented by the formula E/X/Y/Z, where E is the copolymer unit —(CH 2 CH 2 )— derived from ethylene; X is the copolymer unit —(CH 2 CR 1 R 2 )—, where R 1 is hydrogen, methyl, or ethyl, and R 2 is carboalkoxy, acyloxy, or alkoxy of 1 to 10 carbon atoms (X for example is derived from alkyl acrylates, alkyl methacrylates, vinyl esters, and alkyl vinyl ethers); and Y is the copolymer unit —(CH 2 CR 3 R 4 )—, where R 3 is hydrogen or methyl and R 4 is carboglycidoxy or glycidoxy (Y for example is derived from glycidyl acrylate, glycidyl methacrylate, or glycidyl vinyl ether) and Z is derived from comonomers including carbon monoxide, sulfur dioxide, acrylonitrile, or other monomers.
4. The composition of claim 3 wherein X is from 0 to 50 weight % of said E/X/Y/Z copolymer, Y is from 0.5 to 15 weight % of said E/X/Y/Z copolymer, and Z is from 0 to 15 weight % of said E/X/Y/Z copolymer, E being the remainder.
5. The composition of claim 2 wherein said reactant glycidyl-containing ethylene copolymer is an E/X/Y copolymer derived from copolymerization of ethylene, n-butyl acrylate and glycidyl methacrylate.
6. The composition of claim 1 wherein said reactant polystyrene-maleic anhydride copolymer contains 0.5 to 40 weight % maleic anhydride.
7. The composition of claim 6 wherein said reactant polystyrene-maleic anhydride copolymer contains 3 to 20 weight % maleic anhydride.
8. The composition of claim 7 wherein said reactant polystyrene-maleic anhydride copolymer contains 5 to 15 weight % maleic anhydride.
9. The composition of claim 1 wherein said reactant epoxy-containing ethylene copolymer comprises 1 to 4 weight percent of the reaction mixture and said reactant polystyrene-maleic anhydride copolymer comprises 1 to 4 weight percent of the reaction mixture.
10. The composition of claim 1 wherein said reactant epoxy-containing ethylene copolymer is an E/X/Y copolymer derived from copolymerization of ethylene, n-butyl acrylate and glycidyl methacrylate comprises 3% of the reaction mixture and said reactant polystyrene-maleic anhydride copolymer comprises 2 to 3% of the reaction mixture.