Poly degradation, thermogravimetry

Thermogravimetry and gel permeation chromatography data show that poly[(a-carboxymethyl)alkyl isocyanides) also undergo degradation which becomes rapid at temperatures above 50° C. However, at room temperature this process is sufficiently slow so as not to confuse the observations reported above. Other polyisocyanides, including copolymers of the above with a-phenylethyl isocyanide, are being synthesized which may prove less complex subjects of study of the phenomena described above. 

The thermal degradation of poly(vinyl bromide), of blends of this polymer with polyfmethyl methacrylate) and of the copolymer of vinyl bromide and methyl methacrylate have been investigated by sub-ambient thermal volatilization analysis and thermogravimetry. The results are discussed in relation to the use of the vinyl bromide unit as a Are retardant. 

Thermal degradation of various polyhydoxyalkanoates, i.e. poly(3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and poly(3-lydroxybutyrate-co-3-hydroxyhexanoate) (PHB-HH) was investigated under nitrogen atmosphere by dynamic thermogravimetry [19]. The incorporation of 30 mol% 3-hydoroxyvalerate (HV) and 15 mol% 3-hydroxyhexanoate (HHx) components into the polyester increased the thermal stability. 

Differential scanning calorimetry (DSC) analyses showed that the copolymers were amorphous, Tg ranging between 77°C and 86°C (Table 20.3). The thermal degradation of poly(AN-co-MATRIF), poly(MAN-co-MATRIF), and poly(MVCN-co-MATRIF) copolymers was studied by means of thermogravimetry. Table 20.3... 

Zou, H., Yi, C., Wang, L., Liu, H., Xu, W., 2009. Thermal degradation of poly(lactic acid) measured by thermogravimetry coupled to Fourier transform infrared spectroscopy. J. Therm. Anal. Calorim. 97, 929-935. 

High-resolution thermogravimetry has been successfully utilised to investigate the thermal degradation of the bisphenol-A poly(sulfone) [a.l98]. The degradation parameters of the bisphenol-A poly(sulfone), involving temperature, maximum decomposition rate, char yield at 800 °C, activation energy, reaction order and frequency factor, exhibit a... 

The thermal decomposition of blends of PEEK with poly(p-hydroxybenzoic acid-co-2,6-hydroxynaphthoic acid) (PHAHNA) using thermogravimetry under dynamic conditions has been investigated [a.355]. The thermal analysis of the blends showed that thermal stability is clearly affected with respect to the unblended materials - blending accelerates the degradation process. In the case of PHAHNA, the liquid-crystalline polymer was... 

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