Characterization and Properties of Reactive Poly(lactic acid)/Polyamide 610 Biomass Blends

A low molecular weight bisphenol-A type epoxy resin was used as a reactive compatibilizer for poly(lactic acid) (PLA)/polyamide 610 (PA 610) biomass blends. To the best of our knowledge, this blend is the first biomass PA 610 blend in the literature. The epoxy functional groups could react with the terminal groups of both PLA and PA 610. An ester-amide interchange reaction led to a polyester-polyamide copolymer formation, and improved the compatibility of PLA and PA 610. The blends with epoxy resin showed an enhancement in the phase dispersion and interfacial adhesion compared with the blend without epoxy resin. The differential scanning calorimetry (DSC) analysis showed that the crystallization peak temperatures decreased with increasing epoxy content. The melting temperature of PA 610 decreased with the addition of PLA, but remained unchanged with increased compatibilizer dosages. The dynamic mechanical analysis (DMA) showed that the glass transition temperature (T-g) of the blend, with the addition of 0.5 phr epoxy resin, slightly increased compared with that of neat PLA. However, the T-g of the blends remained unchanged with increasing epoxy resin content, and the higher content of epoxy resin in the blends resulted in improved mechanical properties and higher melt viscosity. The unnotched impact test showed that PA 610 could toughen PLA with the addition of epoxy resin. Moreover, the no-break unnotched impact behavior was observed with the medium content of the compatibilizer, improving the notch sensitivity of PLA. (c) 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 2563-2571, 2013