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Evaluation of the Thermal Stabilization Effect of Maleic Anhydride Derivatives on Polyvinyl Chloride

Here, we synthesized a series of polymeric thermal stabilizers for polyvinyl chloride (PVC) based on maleic anhydride derivatives, including N-phenylmaleimide (NPMI), N-p-chlorophenyl maleimide (NCIPMI), N-p-nitrophenyl maleimide (NNOPMI), dibutyltin maleate (DBTM) and dioctyltin maleate (DOTM). Five specimens were prepared by mixing and rolling through a blending machine and a double-roller mixer, respectively. These samples were first subjected to thermal degradation in a 180°C hot oven, and fractions were collected every 10 min, followed by spotting on a slip of test paper. From the degree of color change in the test paper, the influences of these compounds on the thermal stability of PVC were estimated and such mechanisms were also discussed.