TITLE:
Effect of Melt Mixing Time in Internal Mixer on Mechanical Properties and Crystallization Behavior of Glycidyl Methacrylate Grafted Poly (Lactic Acid)
AUTHORS:
Nguyen Chi Thanh, Chaiwat Ruksakulpiwat, Yupaporn Ruksakulpiwat
KEYWORDS:
PLA, Grafting, PLA-g-GMA, Mixing Time, Crystallization
JOURNAL NAME:
Journal of Materials Science and Chemical Engineering,
Vol.3 No.7,
July
1,
2015
ABSTRACT: Glycidyl methacrylate (GMA) was grafted
onto poly (lactic acid) (PLA) by melt mixing in internal mixer using dicumyl
peroxide (DCP) as an initiator. The results from proton nuclear magnetic resonance
(1H-NMR) and Fourier transform infrared (FTIR) spectroscopy indicated that the
grafting reaction of GMA onto PLA took place successfully. The impact strength
of PLA-g-GMA was significantly higher than that of pure PLA. The crystallinity
of PLA, obtained from differential scanning calorimetry (DSC), decreased after
grafting. In order to obtain the optimal mixing conditions, the mixing time was
varied into 7, 10 and 14 min. The optimum mixing time of 10 min was found to give
the optimum mechanical properties of glycidyl methacrylate grafted poly (lactic
acid) (PLA-g- GMA). However, the mixing time played no important role in impact
behavior of PLA-g-GMA. In addition, the highest crystallinity was obtained with
the PLA-g-GMA prepared with the mixing time of 7 min.