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

Autor: Brian A. Newman, Jerry I. Scheinbeim, David L. Winsor
Rok vydání: 1999
Předmět:
Zdroj: Journal of Polymer Science Part B: Polymer Physics. 37:19-28
ISSN: 1099-0488
0887-6266
Popis: 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 fluoride–trifluoroethylene) (VF2/VF3) 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 (≈ 58%) and an increased dielectric constant (≈ 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 −100°C to 100°C. This data showed that for slow-cooled films the glass transition temperature decreased from −28°C to -52°C at the highest doping level. DSC thermal analysis shows a decrease in the Curie transition (≈ 4°C) and melting temperatures (≈ 9°C) for the quenched films, while the slow-cooled films only showed a decrease in melting temperature (≈ 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. © 1999 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 37: 19–28, 1999
Databáze: OpenAIRE
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