Preparation And Properties Of ABS/Nano-ZnO/CCA Composites For Refrigerator Antibacterial Under Visible Light

The refrigerator is a commonly used household appliance.It brings convenience to people’s lives,however,it is also very easy to nourish bacteria,resulting in food spoilage and nutrient loss.At present,the common refrigerator sterilization device on the market uses the principle of ultraviolet and ozone sterilization to sterilize.Both two sterilization methods have an adverse effect on people’s health and accelerate the aging of plastic parts of the refrigerator.Therefore,it is of great practical significance to develop a healthy refrigerator sterilization method under visible light.In this work,ABS/Nano-ZnO composite antibacterial materials were prepared by melt blending.The contact antibacterial properties were explored by filming method.Secondly,using the principle of absorption-transmission of visible light by chlorophyll copper acid(CCA)to improve the photocatalytic antibacterial efficiency of Nano-ZnO,ABS/Nano-ZnO/CCA composite antibacterial materials were prepared,and non-contact refrigerator antibacterial performance of the materials were explored under visible lights with air circulation system.Finally,the modified Nano-ZnO was characterized by fourier transform infrared spectroscopy(FTIR)and activation index.The effects of Nano-ZnO content,CCA and coupling agent on the properties of composites were investigated by characterizing the antibacterial properties,mechanical properties,thermal properties,rheological properties,micromorphology and EDS of the above composites.Main contents and conclusions as follows:(1)ABS/Nano-ZnO composite antibacterial materials with Nano-ZnO content of 0.2～1.0 wt%were prepared by melt blending method.The effect of Nano-ZnO content on the properties of composites was studied.The results show that when the content of Nano-ZnO is 0.2 wt%,the antibacterial rate of ABS/Nano-ZnO composites is only 87.1%,indicating no clear antibacterial effect;when the content of Nano-ZnO is 0.4 wt%～0.6 wt%,the antibacterial rate of the composite is more than 90%but less than 99%,that is,the composites have antibacterial effect but does not have strong antibacterial effect;when the content of Nano-ZnO is 0.8 wt%,the antibacterial rate of the composite material reaches 99.2%,indicating a strong antibacterial effect.The results of mechanical properties test show that the Nano-ZnO content of 0.2～1.0 wt%have little effect on the tensile strength and bending properties of ABS/Nano-ZnO composite materials.Thermogravimetric analysis(TGA)showed that the thermal decomposition temperature of the material was slightly increased.(2)On the basis of ABS/Nano-ZnO research,the ABS/Nano-ZnO/CCA composite antibacterial materials were prepared with the Nano-ZnO content of 0.2-1,0 wt%and 2.5～10.0wt%and CCA was added in a mass ratio of m(Nano-ZnO):m(CCA)=3:1.The interaction between Nano-ZnO and CCA was proved by UV and IR spectra.The antibacterial properties of the composites with Nano-ZnO content of 0.2-1.0 wt%were measured by contact antibacterial method.The antibacterial properties of the composites with the Nano-ZnO content of 2.5-10.0 wt%were measured by non-contact antibacterial method under visible light in the refrigerator.The results show that the antibacterial property of the composite material is greatly improved after the addition of CCA.When the content of Nano-ZnO is 0.2 wt%,the material has reached a strong antibacterial effect of more than 99%;the non-contact antibacterial experiment of the materials show that the wind circulation system,antibacterial grid area and Nano-ZnO content will affect the antibacterial effect of the material.When the volume of cold storage space is 115 L,the wind circulation is relatively uniform,the antibacterial plate area is 576 cm2，the Nano-ZnO content is 5 wt%or more,the non-contact antibacterial rate can reach 99%.The mechanical properties show that tensile strength does not change much,and the bending properties are improved,when the content of Nano-ZnO is 2.5～10.0 wt%.The TGA analysis showed that the initial decomposition temperature of the composite increased to 402 ℃.(3)Nano-ZnO was modified with 1～5%silane coupling agent KH550，obtaining ABS/GNano-ZnO/CCA composite antibacterial materials with different modifier dosages.When the dosage of KH550 is 2%,the comprehensive performance of the composite antibacterial material is the best.The ABS/GNano-ZnO/CCA composite antibacterial material with graft modified Nano-ZnO content of 2.5～10.0 wt%was prepared by modifying the Nano-ZnO with 2%coupling agent.The results show that when the content of Nano-ZnO is 2.5 wt%，the non-contact antibacterial rate is improved,and the tensile strength,flexural modulus and flexural strength are improved.The Zn element distribution shows that the surface modification of Nano-ZnO can improve its dispersion in the matrix.The rheological behavior shows that with the increase of GNano-ZnO content,the storage modulus,loss modulus and complex viscosity.of composite antibacterial materials increase.