Investigation of the effect of nano-SiO2 modified by 3-aminopropyltriethoxysilane on biobased polyamide 56 crystallization behavior

Bio-based polyamide 56 (PA56), a sustainable alternative to petroleum-based polyamide 66 (PA66), exhibits a slow crystallization rate that poses a significant challenge to its broader application. The modification of SiO2 using 3-aminopropyltriethoxysilane (APTES) can markedly enhance its dispersion and interfacial compatibility, thereby improving the mechanical interlocking effect of the material. In this study, unmodified nano-SiO2 (UMS)/PA56 and APTES modified nano-SiO2 (AMS)/PA56 composite materials were synthesized through melt blending technology. The non-isothermal and isothermal crystallization kinetics of PA56 composites were analyzed by x-ray diffraction and differential scanning calorimetry, and the effects of different SiO2 addition ratios on the crystalline properties were investigated. Experimental results indicate that as the proportion of UMS increases, the crystallization behavior of the composite material gradually weaks; conversely, the addition of AMS results in an enhanced crystallization behavior. Notably, at a cooling rate of 10 degrees C/min, the crystallization rate (Z(t)) of AMS and UMS composites increased by 135% and 122%, respectively, compared to pure PA56, while the semi-crystallization time (t(1/2)) decreased by 24.4% and 23.6%, respectively.