Study of a plasticized-unoriented P(VF2/VF3) (73/27 mol%) copolymer. I. The effects of crystallization conditions on morphology, physical, and thermal properties

✍ Scribed by David L. Winsor; Jerry I. Scheinbeim; Brian A. Newman

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 250 KB
• Volume: 37
• Category: Article
• ISSN: 0887-6266
• DOI: 10.1002/(sici)1099-0488(19990101)37:1<19::aid-polb2>3.0.co;2-w

✦ Synopsis

The results of a study on the effects of a plasticizer, tricresyl phosphate, on the mechanical and thermal properties of unoriented films of poly(vinylidene fluoridetrifluoroethylene) (VF 2 /VF 3 ) copolymer (73/27 mol%) are presented. Films were prepared by both quenching and slow-cooling from the melt with plasticizer concentrations of 0, 5, and 10% by weight. For the slow-cooled films, a reduction in crystallinity by 25% was observed for the heavily plasticized films, together with a reduced dynamic mechanical modulus (Ϸ 58%) and an increased dielectric constant (Ϸ 200%). For the quenched films, a small increase in crystallinity was observed together with a reduced modulus and an increased dielectric constant. Measurements of the temperature dependence of the modulus and dielectric constant at 10 Hz. were also carried out from Ϫ100°C to 100°C. This data showed that for slow-cooled films the glass transition temperature decreased from Ϫ28°C to -52°C at the highest doping level. DSC thermal analysis shows a decrease in the Curie transition (Ϸ 4°C) and melting temperatures (Ϸ 9°C) for the quenched films, while the slow-cooled films only showed a decrease in melting temperature (Ϸ 10°C), while the Curie transition temperature was unaffected. In addition, evidence of a two-phase system or a nonferroelectric crystal phase is noted by the presence of two Curie transition temperature peaks.