Solution properties of a propylene-tetrafluoroethylene copolymer

✍ Scribed by S Florián; E Lathová; P Mach

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 212 KB
• Volume: 30
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(94)90042-6

✦ Synopsis

Solution properties of a propylene-tetrafluoroethylene 0aTFE) copolymer were studied in a thermodynamically good solvent (tetrahydrofuran, THF) and in poor solvents (n-butyl acetate, methyl isobutyl ketone). Mark-Houwink relations were determined for the copolymer in particular solvents and unperturbed dimensions, Ko = 1.58 x 10 -3 were established. The low values of the Mark-Houwink exponents of 0.19-0.36 in n-butyl acetate and methyl isobutyl ketone show that the molecules of the copolymer are in the mentioned solvents in a more compact configuration. A segment CH3---CH2---CHCH3---CF2---CFz---CH 3 (the basic segment of an alternating PTFE copolymer) was studied by the semi empirical SCF method AM I. The segment was found to contain conformationally a very flexible bond which enables formation of the more compact structures.