Cross-linking of tetrafluoroethylene-perfluoro (methylvinyl ether) elastomers with electron beam irradiation

✍ Scribed by A. L. Logothetis

• Publisher: John Wiley and Sons
• Year: 1997
• Tongue: English
• Weight: 178 KB
• Volume: 63
• Category: Article
• ISSN: 0021-8995
• DOI: 10.1002/(sici)1097-4628(19970110)63:2<147::aid-app2>3.0.co;2-v

✦ Synopsis

Perfluoroelastomeric articles were cross-linked by electron beam irradiation. Irradiation experiments were carried out on the pure polymer free of fillers, processing aids, or curing chemicals. Doses of 10-15 Mrads are adequate to give gel content of ú95%. The compression set, tensile strength, and chemical resistance of O-rings thus crosslinked are very good and comparable to those of chemically cross-linked ones. There is little difference in terms of efficiency of cross-linking and properties among perfluoroelastomers containing various functionalities, such as nitrile, iodine, bromine, hydrogen, and perfluorbenzene. In addition to cross-linking, irradiation causes structural changes, such as formation of acid fluorides on the polymeric chain ends as a result of main-chain scissions and generation of small amounts of volatile products (CF 4 , COF 2 , CO 2 , CF 3 OCF 3 ) attributed to side-chain scissions. The cross-links appear to be thermally and chemically stable carbon-carbon bonds.