Abstract A molded article simulating the appearance of natural plantation crepe rubber and a method for producing this article. Styrene/butadiene linear or radial block copolymer having a polymerized styrene content of the range of about 20 to about 50 weight percent of the total block copolymer and resinous polymer of vinyl-substituted aromatic compound in the range of about 10 to about 60 parts resinous polymer per 100 parts block copolymer are blended with a sufficient amount of polarizing agent to achieve rapid heating through response to microwave treatment. The composition is melted, molded against a surface mirroring the appearance of plantation crepe rubber, and removed from the mold as an article simulating plantation crepe rubber. In an embodiment of the invention with chemical blowing agent incorporated into the molding composition, an amount of the molding composition is introduced with the mold that upon activation of the blowing agent during the molding operation produces a molded article having a normally dense skin with a microporous interior.
A molding composition comprising: (1) styrene/butadiene linear or radial block copolymer elastomer having a polymerized styrene content in the range of about 20 to about 50 wt. % of total block copolymer the remainder being polymerized butadiene, (2) resinous solid polymer of vinyl-substituted aromatic compound in the range of about 10 to about 60 parts resinous polymer per 100 parts block copolymer elastomer, (3) a sufficient amount of polarizing agent to permit rapid heating using energy of microwave frequencies said polarizing agent chosen from the group consisting of simple and polymeric alkylene glycols and their mono- and dialkyl ethers, and ethanolamines and isopropanolamines and their hydrocarbyl-substituted derivatives, and (4) sufficient blowing agent dispersed throughout the rest of the composition upon activation to provide microporous structure within a skin of normally dense polymer.
Claim 2
Dependent Claim
132 words
A molding composition comprising: (1) styrene/butadiene linear or radial block copolymer elastomer having a polymerized styrene content in the range of about 20 to about 50 wt. % of total block copolymer the remainder being polymerized butadiene, (2) resinous solid polymer of vinyl-substituted aromatic compound in the range of about 10 to about 60 parts resinous polymer per 100 parts block copolymer elastomer, (3) a sufficient amount of polarizing agent to permit rapid heating using energy of microwave frequencies said polarizing agent chosen from the group consisting of simple and polymeric alkylene glycols and their mono- and dialkyl ethers, and ethanolamines and isopropanolamines and their hydrocarbyl-substituted derivatives, and (4) sufficient blowing agent dispersed throughout the rest of the composition upon activation to provide microporous structure within a skin of normally dense polymer.
Claim 3
Dependent Claim
27 words
A molding composition of claim 1 wherein the amount of blowing agent is in the range of about 0.5 to about 10 php of total polymeric mixture.
Claim 4
Dependent Claim
27 words
A molding composition of claim 2 wherein the amount of blowing agent is in the range of about 3 to about 6 php of total polymeric mixture.
Claim 5
Dependent Claim
22 words
A molding composition of claim 1, 2 or 3 wherein said composition also comprises compounds chosen from among odorants, colorants, and fillers.