# US 5,332,771 A · High-performance water-based chloroprene polymer adhesive composition > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,332,771 A - Document ID: US5332771A - Status: Granted - Kind: A - Application number: 07/986,449 - Filed: 1992-12-07 - Granted: 1994-07-26 - Earliest claimed: 1992-12-07 - Assignees: E. I. Du Pont de Nemours and Company - Inventors: Lance A. Christell - Web page: https://patentgrep.com/patent/US5332771A ## CPC - C09J 111/00: Adhesives based on homopolymers or copolymers of chloroprene - C09J: ADHESIVES; NON-MECHANICAL ASPECTS OF ADHESIVE PROCESSES IN GENERAL; ADHESIVE PROCESSES NOT PROVIDED FOR ELSEWHERE; USE OF MATERIALS AS ADHESIVES (preparation of glue or gelatine C09H) ## Abstract An adhesive composition resistant to elevated temperature and particularly suitable for bonding to a substrate a composite structure thermoformable at a high temperature is an aqueous dispersion containing as its main components a copolymer of 2-chloro-1,3-butadiene with 2,3-dichloro-1,3-butadiene made at a temperature of at most 35.degree. C., preferably at most 25.degree. C., a rosin ester, and zinc oxide or magnesium oxide. The solids content of the adhesive composition is about 40-65 weight percent, preferably 50-60 weight percent. The composition may also contain, and usually does contain, further additives such as, for example, stabilizers, antioxidants, surfactants, and gum rosin esters. ## Claims ### Claim 1 An adhesive composition particularly suitable for use in applications requiring postforming consisting essentially of about 100 parts of a copolymer of 2-chloro-1,3-butadiene with 2,3-dichloro-1,3-butadiene, the proportion of 2,3-dichloro-1,3-butadiene being 2% to 20% based on the total weight of the copolymer, 15 to 75 parts of rosin ester; 1 to 10 parts of a metal oxide selected from the group consisting of zinc oxide and magnesium oxide, all parts being by weight; and a sufficient amount of water to make the solids content of the composition 40-65 weight percent; with the proviso that said copolymer of 2-chloro-1,3-butadiene with 2,3-dichloro-1,3-butadiene is prepared by free radical emulsion copolymerization of the comonomers in the presence of 0.05 to 0.3 weight percent of a dialkylxanthogen disulfide, based on the total weight of the two comonomers, at a temperature within the range of about 0.degree. C. to 35.degree. C. ### Claim 2 (depends on 1) A composition of claim 1 wherein the amount of 2,3-dichloro-1,3-butadiene in the copolymer is 4-10 weight percent. ### Claim 3 (depends on 1) A composition of claim 1 wherein the amount of solids is 50-60 weight percent. ### Claim 4 (depends on 1) A composition of claim 1 wherein the metal oxide has a surface area of at least 2 m.sup.2 /g. ### Claim 5 (depends on 1) A composition of claim 1 wherein the copolymer of 2-chloro-1,3-butadiene with 2,3-dichloro-1,3 butadiene is made at a temperature of at most 25.degree. C. ### Claim 6 (depends on 1, 2, 3, 4, 5) An adhesive composition of any one of claims 1-5 further containing at least one additional component selected from the group of stabilizers, surfactants, antioxidants, and gum rosin esters; the gum rosin esters, if present, being about 5-50 parts by weight, based on 100 parts by weight of the chloroprene copolymer. ### Claim 7 A structure comprising at least two layers of the same or different materials bonded to one another with an adhesive composition consisting essentially of about 100 parts of a copolymer of 2-chloro-1,3-butadiene with 2,3-dichloro-1,3-butadiene, the proportion of 2,3-dichloro-1,3-butadiene being 2% to 20% based on the total weight of the copolymer; 15 to 75 parts of rosin ester; 1 to 10 parts of a metal oxide selected from the group of zinc oxide and magnesium oxide, all parts being by weight; and a sufficient amount of water to make the solids content of the composition 40-65 weight percent; with the proviso that said copolymer of 2-chloro-1,3-butadiene with 2,3-dichloro-1,3-butadiene is prepared by free-radical emulsion copolymerization of the comonomers in the presence of 0.05 to 0.3 weight percent of a dialkylxanthogen disulfide, based on the total weight of the two comonomers, at a temperature within the range of about 0.degree. C. to 35.degree. C.; said structure being capable of withstanding a temperature of at least 120.degree. C. without separation of the layers. ### Claim 8 (depends on 7) A structure of claim 7 which is capable of withstanding a temperature of about 163.degree. C. without delamination. ### Claim 9 (depends on 7) A structure of claim 7 wherein the adhesive composition further contains at least one additional component selected from the group of stabilizers, surfactants, antioxidants, and gum rosin esters; the amount of gum rosin esters, if present, being about 5-50 parts by weight, based on 100 parts by weight of the chloroprene polymer. ### Claim 10 (depends on 7, 8, 9) A composite structure of any one of claims 7 through 9 wherein the copolymer of 2-chloro-1,3-butadiene with 2,3-dichloro-1,3-butadiene in the adhesive composition is made at a temperature within the range of 0.degree. C. to 25.degree. C., and the amount of 2,3-dichloro-1,3-butadiene in the copolymer is 4-10 weight percent.