Mechanical and thermal properties of thermotropic liquid crystalline copolyester (tlcp) and its mixtures with poly(ethyleneterephthalate) and denture base poly(methyl methacrylate)

Öztürk, Hale Bahar
In this study, the thermal and mechanical properties of poly(ethylenetheraphthalate) (PET)-thermotropic liquid crystal polyester (TLCP), mixtures and poly(methyl methacrylate) (PMMA)-TLCP mixtures were studied. The curing of PMMA-TLCP mixtures was done by heat, gamma radiation and microwave. The amount of TLCP in mixtures was % 0.5, 2 and 5 TLCP by weight. TLCP was synthesized by melt-acidolysis system, and PET-TLCP mixtures were prepared by using lab scale batch mixer. PMMA samples were prepared according to denture manufacturer̕s procedure. The characterization of polymer samples and mixtures were carried by FT-IR, NMR, DSC, DMA, tensile, impact, three point bending tests and light microscopy. The mixing of TLCP with PMMA yielded heterogeneous dispersions. This was observed from light micrographs. The mechanical and rheological properties of all polymers were not positively affected by inclusion of TLCP. It is also worthwhile to note that weakening of PET-TLCP mixtures were due to the thermal degradation as the thermal age of the mixtures is much higher.


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Citation Formats
H. B. Öztürk, “Mechanical and thermal properties of thermotropic liquid crystalline copolyester (tlcp) and its mixtures with poly(ethyleneterephthalate) and denture base poly(methyl methacrylate),” M.S. - Master of Science, Middle East Technical University, 2004.