Authors:T. C. K. Yang, W. H. Chang, and D. S. Viswanath
Thermal degradation of poly(vinyl butyral) (PVB) and its mixtures with alumina, mullite and silica was investigated by non-isothermal thermogravimetry in the temperature range of 323 to 1273 K. The analysis of the data was carried out using a three-dimensional diffusion model. Results showed that the kinetic parameters (activation energy and pre-exponential factor) of the PVB degradation are different for polymer alone, and ceramic/polymer composites. The overall weighted mean apparent activation energy showed an increasing reactivity in the order of PVB<alumina+PVB<mullite+PVB<silica+PVB. This shows that the acidic and basic surface characteristics of the ceramics promote the thermal degradation of PVB and, the more acidic silica affects the degradation more than mullite and alumina. The effect of pellet compression pressure in the range of 4000 to 8000 psig is also investigated.
Authors:Stéphanie Etienne, Claude Becker, David Ruch, Albert Germain, and Cédric Calberg
In order to improve poly(vinyl chloride) (PVC) thermal stability, poly(vinyl butyral) (PVB) matrix and calcium carbonate nanoparticles
were incorporated in plasticized PVC. Thermal properties of these composites were investigated by thermogravimetry analysis
coupled with mass spectrometry and Fourier transform infrared spectroscopy (FTIR). This approach highlighted the efficiency
of both PVB and CaCO3 as HCl scavengers by postponing both the onset degradation temperature and the HCl release. Moreover, a synergetic effect
was evidenced regarding the HCl release. Finally, kinetic parameters of the PVC first degradation stage, determined using
the Flynn–Wall–Ozawa’s method, revealed a significant increase of the activation energy by incorporation of CaCO3 in the presence or not of PVB.
, 227 – 233 . 10.1590/1678-5150-pvb-6438 Yang , D. K. , Park , Y. N. , Hong , G. S. , Kang , H. K. , Oh , Y. I. , Cho , S. D. and Song , J. Y. ( 2011 ): Molecular characterization of Korean rabies virus isolates . J. Victorian Cult. 12