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.

Thermally conductive biomass composites were prepared using poly(lactic acid) (PLA)/polyamide 610 (PA 610) blends as the matrix and a hexagonal boron nitride (BN) as the thermally conductive filler via a melt-blending process. The experimental results showed that BN was dispersed in the blends as the flake type morphology. Tg (glass transition temperature) and Tm (melting temperature) of both PLA and PA 610 remained unchanged, but the thermal degradation temperature increased up to 30°C with the addition of 50 phr BN in the blends. The tensile strength and tensile modulus increased with the incorporation of BN in the blends. The thermal conductivity of the blends could be improved with the addition of BN, reaching the highest level of 0.86 W m−1·K−1 for the 50 phr-filled composite. The thermal conductivities of the composites were successfully predicted via a semi-theoretical mathematical model proposed by Lewis and Nielsen.

A melt blending process was used to prepare poly(lactic acid) (PLA)/metallocene catalyzed polyethylene octene copolymer (POE) blends in order to toughen PLA. A commercialized ethylene-glycidyl methacrylate copolymer (EGMA) was applied as a compatibilizer to improve the dispersion and interaction of dispersed POE to the PLA matrix. The results showed that chemical interaction seems to be the driving force for reinforcing the compatibility between PLA and POE, and also the dispersion of POE into the PLA matrix domain. With the incorporation of 10 phr EGMA in the blends, POE was welldispersed at a sub-micrometer scale within the PLA matrix, indicating better interfacial compatibility between PLA and POE. The impact strength test revealed that POE could signifi cantly toughen PLA containing EGMA in the blends, up to no-break level regarding unnotched Izod impact strength at 10 phr EGMA content. With the increase of EGMA content, the blends showed lower tensile strength, but higher elongation at break due to the elastomeric characteristics of EGMA. When 10 phr of the EGMA was incorporated into the blends, its elongation at break reached 54.5 % , 10.7 times that of neat PLA at 5.1 % . The melt viscosity of compatibilized blends containing 10 phr EGMA increased by more than 50 % in comparison with the non-compatibilized blend, which implied a good interfacial interaction between the PLA and POE interface.