Polymers with pendent functional groups. V. Thermooxidative and thermal behavior of chloromethylated polysulfones

The first step of the thermooxidative and thermal decomposition of some chl oromethylated polysulfones (CMPSF) with various degrees of substitution has been studied by thermogravimetry (TG) and thermal volatilization analysis (TVA). A step occurring at lower temperatures 260-370 degrees C is particul ar for halomethylated polysulfones because the polysulfone (PSF) is thermal ly stable in this temperature range (its first decomposition step occurs fr om 400 to 550 degrees C). The higher the degree of substitution, the lower the degradation temperature and a better separation of the processes was fo und. The thermal decomposition products collected were analyzed by IR spect roscopy and elemental analysis. According to our TG and TVA results and lit erature data, it call be proposed that -CH2Cl groups react at low temperatu res giving cross-linked polymer and gas or liquid products. The thermal cha racteristics of this process depend on the chlorine content of the sample a nd explain undesirable cross-linking that could take place during the synth esis of the chloromethylated polysulfones. (C) 2000 Elsevier Science Ltd. A ll rights reserved.