This paper presents an overview of the recent literature on flame retardancy of polycarbonate (PC) and polycarbonate-based resins. A brief survey of the major mechanisms of thermal decomposition of PC is also presented because it gives insight in the mechanisms of flame retardant action. Mostly industrial laboratories are involved in the development of new flame retardants for PC and, to a much lesser extent, academic laboratories are doing research on the mechanistic aspects of flame retardancy. The number of patents published annually on the flame retardancy of PC and its blends significantly exceeds the number of patents on flame retardancy of any other polymer. Because PC is a naturally high charring polymer, the condensed phase active flame retardants, in particular phosphorus-based ones, are widely used in PC-based blends. Plain PC can pass stringent flame retardant tests with very low additions of some sulfur- or silicone-based flame retardants. Copyright © 2005 Society of Chemical Industry

Overview of recent developments in the flame retardancy of polycarbonates

Polycarbonate nanocomposites: Part 2. Degradation and color formation

Polycarbonate, poly(bisphenol A carbonate), PC, is an important engineering polymer with a variety of optical and technical applications, whose demand is increasing year by year. Its consumption in 2008 was estimated to have reached 3.3 Mt and to increase by a 7 % per year. The three different routes for PC recycling are: direct recycle (mechanical recycling or blending with other materials), treatment via chemical methods and thermochemical methods (pyrolysis). The aim of the current review paper is to visit all the available methods for PC recycling and their mechanisms and record their potential and weaknesses. Apart from methods such as pyrolysis and degradation via chemical routes, novel methods, such as decomposition in the presence of enzymes, are been reported. Finally, the main degradation methods of PC blends and WEEEs applications are also been presented.

Recent Advances in Polycarbonate Recycling: A Review of Degradation Methods and Their Mechanisms

The thermal decomposition pathways leading to the formation of volatile compounds and to char residue in poly(bisphenol A carbonate) (PC), poly(resorcinol carbonate) (PRC), and poly(hydroquinone carbonate) (PHC) have been investigated by mass spectrometry. The structure of the volatile compounds obtained in the temperature range 300−700 °C, by direct pyrolysis mass spectrometry (DPMS), suggests that these polycarbonates undergo thermal decomposition by a number of different pyrolysis processes. In the initial stage of the thermal degradation are generated cyclic oligomers by an intramolecular exchange reaction, whereas the evolution of CO2 and H2O is spread over all the pyrolysis temperature range, being responsible for the formation of ether bridges (decarboxylation) and phenolic end groups (hydrolysis). A disproportionation reaction of the BPA isopropylidene bridges of PC itself takes place at higher temperature yielding phenyl and isopropylidene end groups, whereas pyrolysis products containing dibenzo...

Thermal Decomposition Processes in Aromatic Polycarbonates Investigated by Mass Spectrometry

http://yoksis.bilkent.edu.tr/pdf/files/10.1016-j.memsci.2010.09.037.pdf

Cyclodextrin functionalized poly(methyl methacrylate) (PMMA) electrospun nanofibers for organic vapors waste treatment

A comparison is drawn between the thermal behaviour of poly-[2,2-propane-bis-(4-phenyl carbonate)] and the model compound diphenyl carbonate. On this basis a rearrangement mechanism is suggested to account for the main chemical and physical features of the degradation of the polymer between 300 and 389°.

A. Davis

Papers

Thermal degradation of polycarbonate