Study On Miscibility Of PLA And PMMA

Polylactic acid (PLA)/poly (methyl methacrylate) (PMMA) were prepared by melting blending. PLA and PMMA with different characteristics were selected and series of PLA/PMMA blends were obtained.Then the miscibility of PLA/PMMA blends was studied.(1) Amorphous polylactic acid (DL-PLA) and poly methyl methacrylate (PMMA) with different Mw were blended by melting mixing. And then the misciblity of DL-PLA and PMMA was investigated. Dynamic mechanics analysis test results and the data of DSC showed that only one glass transition temperature (Tg) appeared in the melting blends, which suggested that DL-PLA and PMMA have good miscibility. The Tg of the DL-PLA/PMMA blends obeyed the Gordon-Taylor equation. It was found that the Tg of DL-PLA/PMMA move to higher temperature with the increase of PMMA molecular weight. Meanwhile, the transparency and mechanical properties of DL-PLA/PMMA melting blends were also investigated.(2) PLLA with different crystallinity and PMMA with different Mw were blended by melting mixing. And then the misciblity of PLLA and PMMA was investigated. Dynamic mechanics analysis test results and the data of DSC showed that only one Tg appeared in the melting blends, which suggested that PLLA and PMMA have good miscibility. The Tg of the PLLA/PMMA blends obeyed the Fox equation. That is to say, PLLA can form miscibility system with PMMA when PLLA is non-crystalline state. It was found that the Tg of PLLA/PMMA move to higher temperature with the increase of PMMA molecular weight.Meanwhile, the transparency and mechanical properties of PLLA/PMMA melting blends were also investigated.(3) PMMA with different functional group were blended with DL-PLA and PLLA by melting mixing. Then the miscibility of the blends was studied.The data of DSC showed that only one Tg appeared in the melting blends, which suggested that DL-PLA/PMMA and PLLA/PMMA with different functional group have good miscibility.