๐”– Bobbio Scriptorium
โœฆ   LIBER   โœฆ

Dielectric behavior of P(VDF-TrFE)/PMMA blends

โœ Scribed by L. O. Faria; R. L. Moreira


Publisher
John Wiley and Sons
Year
1999
Tongue
English
Weight
193 KB
Volume
37
Category
Article
ISSN
0887-6266

No coin nor oath required. For personal study only.

โœฆ Synopsis


Binary blends of ferroelectric (vinylidene fluoride-trifluorethylene) copolymer [P(VDF-TrFE)] and amorphous poly(methyl-methacrylate) (PMMA) were investigated over the full range of composition, for the copolymer with 50 mol % of trifluorethylene. Dielectric measurements confirmed that the system becomes amorphous when the PMMA contents exceed 40 wt %. The observed dielectric losses could be attributed to the ferroelectric transition of the copolymer and to molecular relaxations, characteristic of the individual polymers. We demonstrate the thermally activated nature of the โค-PMMA and โค-P(VDF-TrFE) relaxations, with activation energies of 29.3 and 13.5 kcal/mol, respectively. We also demonstrate that the โค-P(VDF-TrFE) relaxation cannot be attributed only to the copolymer glass transition and that its origin is not in the crystalline region, based on experimental evidences.


๐Ÿ“œ SIMILAR VOLUMES


Infrared spectroscopic investigation of
โœ L.O. Faria; R. L. Moreira ๐Ÿ“‚ Article ๐Ÿ“… 2000 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 162 KB ๐Ÿ‘ 1 views

The blending between poly(methyl methacrylate) (PMMA) and ferroelectric (vinylidene fluoride-trifluorethylene) [P(VDF-TrFE)] copolymer chains has been investigated by Fourier transform infrared (FTIR) spectroscopy over the full range of composition, for the copolymer with 50 mol % of trifluorethylen

Effect of X-ray radiation on the structu
โœ H. N. da Cunha; L. H. C. Mattoso; R. M. Faria ๐Ÿ“‚ Article ๐Ÿ“… 1997 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 130 KB ๐Ÿ‘ 2 views

Structural changes in poly(vinylidene fluoride)-trifluoroethylene [P( VDF-TrFE)] copolymers caused by X-ray irradiation were investigated by molecular weight determination, EPR analysis, FTIR spectroscopy, gel content, DSC thermal analysis, Xray diffraction, and piezoelectricity measurements. Sample

Effect of crystallization temperature on
โœ Rinaldo Gregorio Jr.; Marcelo Marino Botta ๐Ÿ“‚ Article ๐Ÿ“… 1998 ๐Ÿ› John Wiley and Sons ๐ŸŒ English โš– 309 KB ๐Ÿ‘ 2 views

A systematic study was carried out on the effect of the crystallization temperature (T cr ), on the phase transitions presented by P(VDF/TrFE) copolymers cast from dimethylformamide (DMF) solution with molar ratios 60/40, 70/30, and 80/20. The results obtained by differential scanning calorimetry (D