PROPERTIES OF POLY(ETHYLENE GLYCOL) METHYL ETHER ACRYLATE- GRAFTED POLYLACTIDE

摘要

Polyethylene glycol (PEG) is known to plasticize PLA but can exhibit migration over time. In order to reduce migration, reactive extrusion was used to chemically graft polylactide (PLA) with low molecular weight poly(ethylene glycol) methyl ether acrylate (APEG). APEG was added in various concentrations (0, 15 and 30 wt%) in the presence of an organic peroxide as a radical initiator. The covalent grafting of APEG on the PLA was evidenced by ATR-FTIR, ~1H NMR. The physical effects of APEG in terms of thermal and flow properties were also investigated. The melt-state viscoelastic properties were characterized by oscillatory shear measurements. The glass transition temperature of the modified PLA was measured using differential scanning calorimetry. As expected, storage modulus decreased with APEG content and the glass transition temperature of the APEG-modified PLA was decreased by approximately 14°C compared to that of pure PLA.