Preparation, physicochemical and preservation properties of Ti/ZnO/in situ SiOx chitosan composite coatings.

Abstract

Among nanomaterials, Ti and ZnO nanoparticles are often chosen as preservation materials because of their antibacterial properties. Chitosan, as a natural biopolymer, has potential because of its abundance, compatibility and antibacterial properties. To improve the physicochemical and preservation properties of in situ SiOx chitosan (CS) composite coating, Ti/ZnO/SiOx CS composite coatings were prepared with Ti-doped ZnO (Ti/ZnO) nanorods and nanoballs. The composite coating structures were characterized by Fourier transform infrared, X-ray diffraction and scanning electron microscopy, and their physicochemical and preservation properties were determined simultaneously. The results show that the Ti/ZnO nanoparticles are beneficial to homogeneous dispersion of in situ synthesized nano SiOx in the CS coating, and that Ti/ZnO nanoballs have better dispersion than Ti/ZnO nanorods. Moreover, strong hydrogen bonds are formed among Ti/ZnO nanoparticles and in situ synthesized nano SiOx and CS molecules, and the primary structure of CS is disorganized. Thereby, the gas permeabilities and mechanical properties of the CS coatings are improved due to modification of Ti/ZnO nanoparticles, and the Ti/ZnO nanoballs/SiOx CS composite coating is optimal. The preservation properties of the CS coatings on Sciaenops ocellatus are significantly improved, and those of Ti/ZnO/in situ SiOx CS composite coatings are superior. The preservation properties of the CS composite coatings on S. ocellatus are significant, and the Ti/ZnO nanoballs/SiOx CS composite coating is even better. Therefore, the co-modification method of in situ nanoparticles and antibacterial nanoparticles may be a promising method to improve the preservation properties of CS coatings. © 2019 Society of Chemical Industry.