Composite with direct bonding between rubber and foam
This disclosure relates to a composite comprising (a) a rubber layer comprising a cured rubber and optionally a first copolymer having carboxyl groups or anhydride groups; and (b) a foam layer comprising a crosslinked ethylene vinyl acetate and optionally a second copolymer having carboxyl groups or glycidyl methacrylate groups; wherein the foam layer has at least one surface adhering to the rubber layer directly, and provided that either the first copolymer or the second copolymer is present, and the composite is free of glues or adhesive films in the interface between the rubber layer and the foam layer.
1. A composite comprising the following components:
(a) a rubber layer comprising a cured rubber that is formed from a composition comprising the rubber and a first copolymer having carboxyl groups wherein the carboxyl groups in the first copolymer are present in an amount of about 0.05 to about 1 weight % based on the total weight of the rubber layer, and wherein the first copolymer having carboxyl groups is a copolymer selected from the group consisting of ethylene-maleic acid monoethyl ester copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, and mixtures thereof; and
(b) a foam layer comprising a crosslinked ethylene vinyl acetate that is formed from a composition comprising the ethylene vinyl acetate and a second copolymer having glycidyl methacrylate groups, wherein the glycidyl methacrylate groups in the second copolymer are present in an amount of about 0.15 to about 3 weight % based on the total weight of the foam layer, wherein the second copolymer having glycidyl methacrylate groups is a copolymer selected from the group consisting of ethylene-glycidyl methacrylate copolymer, ethylene-vinyl acetate- glycidyl methacrylate copolymer, ethylene-butyl acrylate-glycidyl methacrylate copolymer, and mixtures thereof, and wherein the foam layer is free of the first copolymer having the carboxyl groups;
wherein the foam layer has at least one surface adhering to the rubber layer directly, and
wherein the composite is free of glues or adhesive films in the interface between the rubber layer and the foam layer.
2. An article comprising or produced from the composite according to claim 1 .
3. The article according to claim 2 , wherein the article has a peel strength greater than 1.2 N/mm.
4. The article according to claim 2 , wherein the article has a peel strength greater than 1.5 N/mm.
5. The article according to claim 2 , wherein the article has a peel strength greater than 1.7 N/mm.
6. The article according to claim 2 , which is used as a footwear sole, a carpet, a yoga mat, an acoustic panel, or a cushion board.
7. A method for preparing the composite according to claim 1 , comprising:
(1) curing a mixture comprising a rubber, a curative, and a first copolymer having carboxyl groups to obtain a rubber layer, wherein the carboxyl groups in the first copolymer are present in an amount of about 0.05 to about 1 weight % based on the total weight of the rubber layer, and wherein the first copolymer having the carboxyl groups is a copolymer selected from the group consisting of ethylene-maleic acid monoethyl ester copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, and mixtures thereof;
(2) foaming a mixture comprising an ethylene vinyl acetate, a crosslinking agent, a blowing agent, and a second copolymer having glycidyl methacrylate groups to obtain a foam layer, wherein the glycidyl methacrylate groups in the second copolymer are present in an amount of about 0.15 to about 3 weight % based on the total weight of the foam layer, wherein the second copolymer having the glycidyl methacrylate groups is a copolymer selected from the group consisting of ethylene-glycidyl methacrylate copolymer, ethylene-vinyl acetate-glycidyl methacrylate copolymer, ethylene-butyl acrylate-glycidyl methacrylate copolymer, and mixtures thereof, and wherein the foam layer is free of the first copolymer having the carboxyl groups; and
(3) placing the rubber layer on at least one surface of the foam layer to obtain an assembly, and hot pressing the assembly to obtain the composite, and wherein the composite is free of glues or adhesive films in the interface between the rubber layer and the foam layer.