Studies on the Effect of Laser Radiation on the Thermal Stability of Stabilized Poly (Vinyl chloride)

Non-isothermal studies were carried out using thermogravimetry (TG) and differential thermogravimetry (DTG) to obtain the activation energy of decomposition for poly (vinyl chloride), PVC, stabilized by Ethyl, N-phenyl maleimide, 4-carboxylate (ENPMC). Thermal gravitational analysis (TGA) indicated that the ENPMC-PVC samples decompose in two main breaks down stages. The effect of addition of stabilizer (ENPMC), with different concentrations, to PVC was studied. The results indicate that the addition of ENPMC with 0.01 g/1 g PVC enhances the thermal stability of pure PVC. Samples from the 0.01 g ENPMC/1 g PVC were exposed to infrared laser radiation with energy fluencies at levels between 0.95 and 8.53 J/cm2. The results of thermal experiments indicate that the onset temperature of evaporationTo and thermal activation energy of decomposition Ea are affected by the laser energy fluencies owing to the simultaneous processes of degradation and crosslinking. The variation of transition temperatures with either the stabilizer concentration or the laser energy fluencies has been determined using differential thermal analysis (DTA). The results indicate that the irradiation with laser up to 7.11 J/cm2 decreases the melting temperature of the pure PVC and this is most suitable for applications requiring the molding of this polymer at lower temperatures