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

Abstract 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°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. Highlights APTES modifies nano‐SiO₂ to improve its dispersion. The crystallization rate of AMS composite was increased by 135%. The half‐crystallization time of AMS composite was reduced by 24.4%.