Thermal degradation of polyester thermosets prepared using dibromoneopentyl glycol

Abstract

SynopsisPolyester thermosets have been prepared from maleic anhydride, phthalic anhydride, dibromoneopentyl glycol, and styrene, and their thermal degradation has been studied. Thermogravimetry has shown that degradation in air occurs in three main stages. For the 10% bromine polyester, the weight losses corresponded to 16.376, 69.7%, and 13.9% of the original polymer weight-the temperatures of the DTG peak maxima being 217OC, 345OC, and 530°C, respectively. Infrared analysis of the residues showed that above 25OOC there was a gradual reduction in the absorbance of all peaks with increasing temperature, indicating the degradation of all parts of the 3-dimensional polymer structure was occurring in a simultaneous manner. Degradation of the dibromoneopentyl glycol polyesters a t 53OOC in air proved to be a very complex process since a mixture of organic products was produced which gave rise to well over 100 peaks in the capillary column chromatograms. Under the conditions used, the low temperature degradation products proved to be rich in phthalic anhydride with no benzaldehyde being detected. The yields of benzene, toluene, styrene, and naphthalene increased with increase in temperature.

Influence of Graphene Nanoplatelet Lateral Size on the Electrical Conductivity and Electromagnetic Interference Shielding Performance of Polyester Nanocomposites

“…The representatives of the weight derivatives over temperature, seen in Figure 5 b, clearly show two principal decomposition steps during TGA under air (oxidative) environment. A similar behavior is reported in the literature [ 34 , 35 , 36 ]. These two peaks occur in two consecutive stages between the 290 °C and 550 °C temperature range, with the former at the onset of the neat polyester thermal degradation, and the latter at the end of the polyester thermal degradation.…”

Pyrolysis of Flame Retardant Brominated Polyester Composites

“…The temperature at which the maximum rate of weight loss was seen decreased as the proportion of brominated polyester resin increased, as may be seen fromTable 6. The main zone of weight loss ended at an almost identical temperature for all three samples.Previous studies[17][18][19][20] have observed a similar slower initial stage of weight loss from pure phthalic acid-based polyester resins and attributed it to the release of phthalic anhydride, an initial degradation product of this type of polyester[17,19,21]. Skinner and co-workers[18] monitored the thermal degradation of a thermoset, brominated polyester resin in air using a TGA.…”

Flame retardation of dibromoneopentyl glycol on intumescent flame‐retardant/low‐density polyethylene composites

“…Dibromoneopentyl glycol (DBNPG), as a brominated flame retardant, was developed in the 1970s. The products, such as flame‐retarded polyesters and phosphates, synthesized from DBNPG have been studied extensively. With a low bromine content, characteristic quaternary carbon atom, and dihydroxyl structure, DBNPG can act as the carbon source in IFRSs.…”