Polymers for Advanced Technologies
Poly(methyl methacrylate) (PMMA)/copper hydroxy methacrylate (CHM) composites were prepared via solution blending and bulk polymerization. Addition of 3% by weight of the CHM additive using solution blending resulted in a significant increment (~45°C) in thermogravimetric analysis (TGA) T50, the temperature at which 50% of the original polymeric mass is lost. The value T50 increased by 30°C for a PMMA composite with 4% CHM, synthesized via bulk polymerization. Activation energies, Ea, were calculated as a function of conversion fractions (TGA decomposition profile) for the polymeric materials. Analysis of multiple heating rate data using the Flynn–Wall– Ozawa method resulted in Ea values that were 50 kJ mol-1 higher for conversions above 0.5 in the solution blended composite compared to a reference sample of pure PMMA recrystallized from the same solvent. Similar results were obtained for bulk polymerization process with differences in Ea values>30 kJ mol-1 relative to pure PMMA. However, in contrast to previous studies of bulk polymerized samples, the solution-blended composite exhibited no improvement in cone calorimetry determination of total heat release as compared with the reference PMMA sample.