Preparation And Properties Of Silicone Quaternary Ammonium Salt Polymer/Modified Zinc Oxide Hybrid Antibacterial Material

Cotton textiles were widely used and studied in the textile industry because they were quick drying,sweat absorbing and comfortable to wear.However,their porous structure and absorbed sweat provided environment and nutrient sources for the growthing and mutiplying of microorganisms,and consequently increased the possibility of cross-infection caused by microbial transmission.Therefore,it is very necessary to apply antibacterial treatment on.In this study,carbon-based materials and noble metals were used to modify nano ZnO respectively,then the modified nano ZnO was introduced into silicone quaternary ammonium salt-based polymer system by free radical copolymerization to obtain a silicone quaternary ammonium salt/modified ZnO hybrid material.In addition,the application properties of the cotton textile finished by the hybrid materials were also investigated.The synergistic antimicrobial effect of photocatalytic antimicrobial mechanism from modified nano ZnO and contact antimicrobial mechanism from quaternary ammonium salt rendered cotton textiles broad-spectrum and long-term antimicrobial activity,and the silicone chain in polymer could improve the softness of cotton textiles.The research details were described as following:Nano ZnO modified by carbon quantum dots(ZnO@CQDs)was prepared by hydrothermal method.The effect of CQDs amount on the absorbance of nano ZnO was investigated.The results of UV-vis showed that the best absorption capacity of ZnO@CQDs in the UV-vis region was achieved when the ratio of nano ZnO to CQDs was 1:2.PL result showed that the modification of CQDs can significantly separate photo electron-hole pairs in nano ZnO.XRD and FT-IR results showed that the modification of CQDs does not affect the crystal and chemical structure of nano ZnO.The size of the prepared ZnO@CQDs nanoparticle was about 25 nm.The application results showed that the cotton textiles treated with ZnO@CQDs have improved antimicrobial activity than those treated with nano ZnO.When the ratio of ZnO to CQD was 1:2,the antimicrobial rate of the finished cotton textiles to E.coli and S.aureus were 87% and 85%,respectively.However,compared with untreated cotton textiles,the air permeability finished with ZnO@CQDs decreased by 25.8% and the softness decreased by 13.8%.OQAS/(ZnO@CQDs)hybrid material were prepared by introducing ZnO@CQDs into silicone quaternary ammonium salt copolymer system via free radical copolymerization.The results showed that the good stability of OQAS/(ZnO@CQDs)polymer matrix composites was achieved when the dosage of ZnO@CQDs was 0.8% and the pH value of the system was 6.0.TEM and XRD results showed that the OQAS/(ZnO@CQDs)hybrid materials was prepared successfully.The application results showed that when the concentration of finishing solution was 25 g/L,the antimicrobial rate of finished cotton textiles to E.coli and S.aureus can reach 99% and this can still be maintained at more than 90% after 10 washing cycles(equivalent to 50 household washing cycles).Compared with untreated cotton textile,the air permeability finished with OQAS/(ZnO@CQDs)was improved by 49.0% and the softness improved by 4.9%.Noble metal silver modified nano ZnO(Ag-ZnO)was prepared by chemical reduction method.The effect of silver amount on the absorbance of nano ZnO was investigated.The result of UV-vis indicated that the absorbability of Ag-ZnO in the UV-vis region reached optimum condition when the amount of silver source was 2%.XRD result showed that the noble metal silver did not affect the crystal structure of nano ZnO.The size of Ag-ZnO nanoparticles was about 23 nm.The application results showed that the cotton textiles treated by Ag-ZnO with 25 g/L concentration can resist more than 99% of E.coli and S.aureus,and had good mildew resistance.Wheraes,compared with untreated cotton textile,the whitness finished with Ag-ZnO decreased by 69.5% and the softness decreased by 68.8%.OQAS/(Ag-ZnO)hybrid material were prepared by introducing Ag-ZnO into silicone quaternary ammonium salt copolymer system via free radical copolymerization.The results showed that when the dosage of Ag-ZnO was 0.8% and the pH value of the system was 3.0,OQAS/(Ag-ZnO)polymer matrix composites with good stability could be obtained.TEM and XRD results demonstrated that the OQAS/(Ag-ZnO)hybrid materials was obtained successfully.The application results showed that when the concentration of finishing solution was 25 g/L,the antimicrobial rate of finished cotton textiles to E.coli and S.aureus can reach over 99%.After 10 standard washing cycles(equivalent to 50 household washing cycles),the antimicrobial rate of finished cotton textiles can still be maintained above 90% and the whiteness and air permeability of cotton textiles were basically unaffected,and they had a soft handle.By compared the antibacterial activities of ZnO@CQDs,Ag-ZnO,OQAS/(ZnO@CQDs)and OQAS/(Ag-ZnO),it was found that the photocatalytic antimicrobial activity of nano ZnO modified by nano-silver was better than that of CQDs;the introduction of organosilicon segments was conducive to improving the softness of cotton textiles,and the softness of OQAS/(ZnO@CQDs)was the best.