Controllable preparation of polyamide 12@SiO2 composite powders

Abstract

Polyamide 12 (PA12)‐coated SiO2 composite powders were prepared by a dissolution–precipitation method using a mixture of methanol and ethanol as the solvent. The sizes and morphologies of the as‐obtained composite powders were determined and observed using a laser particle size analyzer and a scanning electron microscope. The effects of SiO2 content on the sizes and the thermal properties of PA12@SiO2 composite powders were studied. The results show that the introduction of SiO2 decreases the size of the composite powders. With increasing content of SiO2 to 9.1 wt%, the d (0.5) of the PA12 powders decreases from 94.2 to 56.2 μm. SiO2 promotes the heterogeneous nucleation of PA12, and the size of the composite powders can be tuned by changing the amount of the SiO2. In addition, SiO2 particles increase the melting and crystallization temperatures and the crystallization rate of PA12. POLYM. COMPOS., 40:1251–1257, 2019. © 2018 Society of Plastics Engineers