Molecular simulation of the interaction mechanism between wollastonite and silane and the properties of modified powder filled nylon 6

The physical and chemical properties of wollastonite were optimized through dry modification with silane, and the effects of modification temperature, time, and silane dosage on the modification effect of wollastonite were explored. Infrared spectroscopy was used to characterize the surface functional groups of wollastonite and modified wollastonite. PA6 composite materials were prepared by filling wollastonite and modified wollastonite powder in polyamide 6 (PA 6), and the impact strength, tensile strength, flexural strength, and flexural modulus of the composite materials were tested. The microscopic mechanism of wollastonite modified by SCA1113 (3-Aminopropyltriethoxysilane)was analyzed using molecular simulation. The results show that the optimize modification process conditions of wollastonite are the modification temperature of 80°, the modification time of 20 minutes, and the silane dosage of 0.8%. Unmodified wollastonite filled nylon 6 can improve the rigidity of the composite material but reduce its toughness compared to pure nylon 6 samples, while modified wollastonite filled nylon 6 can simultaneously improve the rigidity and toughness of the material; When silane SCA1113 modifies wollastonite, its reactivity does not come from inside the wollastonite crystal, and the crystal surface (100) is the most reactive, and silane SCA1113 and wollastonite surface are adsorbed to form Si-O-Ca bond.