Study on toughening modification and foaming behavior of biobased polyamide 56/polyamide 66 blends by polyamide elastomer
Biobased polyamide 56(PA56)/polyamide 66(PA66)blends were toughened by using polyamide elastomer(MH2030),and then a series of bio-based polyamide blend foams were prepared through a supercritical CO2 intermittent foaming technology.The effect of MH2030 content on the crystallization,rheological,mechanical properties,and foam-ing behaviors of the PA56/PA66/MH2030 blends was investigated.The results indicated that the introduction of MH2030 improved the viscoelasticity and foaming performance of the blends,leading to a shift of the crystallization peak toward a high temperature.This may be due to the nucleating effect of MH2030 on the crystallization of the blending sys-tem.The addition of MH2030 also increased the toughness of the blends but reduced their rigidity.The blend containing 20 wt%MH2030 exhibits the highest impact strength,which is 30.4%higher than that without MH2030.The foaming behavior and compression performance of the blend foams were investigated.The blend form containing 10 wt%MH2030 exhibits a higher cell density and better matrix mechanical properties.In this case,the blend foam obtained mi-cro-size pores with a smaller cell size of 19.24 μm and higher compressive strength of 0.71 MPa,which was 29.1%higher than that of the non-toughened PA56/PA66 blend foam.