AbstractsEngineering

The overall goal of this research is to apply the principle of green engineering to produce bio-sourced polycarbonate (PC) based composites with properties similar to BPA-PC. To synthesize PC in a more sustainable way, transesterification polymerization with diphenyl carbonate (DPC) was chosen as the production method. The bio-derived monomer, isosorbide, was chosen as the alternative monomer to the traditional petroleum monomer biphenyl-A (BPA). Alumina-polycarbonate (AL-PC) nanocomposites were produced through melt phase in-situ polymerization to improve mechanical and thermal properties. The first focus of this study was to produce nanocomposites of BPA-PC and ALNW using in-situ melt phase polymerization. The result will be compared to those from an earlier study using solution based polymerizationAlumina nanowhiskers (ALNW) were used to synthesize AL-PC nanocomposites using melt phase polymerization, because the hydroxyl groups on the ALNW surface can react with DPC during polymerization. The presence of bonded BPA-PC on the ALNW surface was confirmed following in-situ polymerization. Molecular weight of PC produced are calculated using NMR end group analysis. The effect of solid state polymerization at gradually increased temperature is reported. Heat resistance and mechanical properties of BPA-PC and AL-BPA nanocomposites were compared and evaluated.Copolymer of isosorbide and BPA with a ratio of isosorbide/BPA= 95/5 was observed to have the highest molecular weight among all the isosorbide-based polymers. AL-isosorbide-BPA-PC nanocomposites were synthesized and structurally confirmed by FTIR.In order to optimize the isosorbide-based PC synthesis, kinetics study was done on the transesterification of BPA and isosorbide. The dependence of reaction temperature and monomer composition on the transesterification rate constant of BPA and isosorbide is studied. The unexpected equilibrium behavior of isosorbide transesterification was revealed. A model was built up for isosorbide and BPA copolymerization, and the reliability of the model was proved. The understanding of the reaction kinetics is applied to adjust reaction conditions of the copolymerization, a design of random sequenced or large block copolymer of BPA and isosorbide can be achieved.