Modification Of Composite Nano-TiO₂ And Its Application In Antibacterial Self-cleaning Fluorocarbon Coating

Humankind is facing with the third pollution period marked by inner air pollution after they met with fuliginous pollution and photochemistry fog pollution.It is very urgency to increase human health by improving living and working surroundings, removing inner nocuousness gas and limiting pathogenic microorganism.Study and exploitation on efficient and innoxious antimicrobial material is one of the most important tasks.Combined with photic catalysis technique and nanotechnology which were originated from last century,we try to prepare a kind of coating with antibacterial performance as well as self-cleaning capability.Firstly,composited Nano-TiO₂ was prepared so as to broaden light response range.Furthermore,function groups that can polymerized were grafted on its surface through modification.Finally, modified composited Nano-TiO₂ was combined with crylic acid ester containing Fluorin aiming to prepare inner coating.Its antibacterial performance as well as self-cleaning capability was investigated.The thesis is falen into following four parts:In chapter 1,preparation and application of nano fluorin carbon coating were summarized.Modification,factors of catalysing effect and principle of catalysing were generalized.Design ideas and detail processes of experiment were advanced by the recent literatures and the facts that study and developments on new pattern, efficient and innoxious antimicrobial material are urgent.Firstly,composited Nano-TiO₂ impured by Fe-Ag double element was prepared to broaden its light response range and increase sunlight utliztion rate.Then its surface was modified.As a result,nano paticles were dispersed evenly during polymerization of latex. High-powered building inner coating with antibacterial performance as well as self-cleaning capability was prepared successfully finally.The experimental course would provide theory base and preparation method for obtaining safe,.wide range and perdurable nano self-cleaning antibacterial fluorin carbon coating.In chapter 2,Fe/NT composite nano-particles was prepared with Ti(OC4H9) by sol-gel method.Then Fe-Ag/NT was obtained by aggradation of Ag.UV-Vis,XRD, TEM and nano paticle instrument were used to characterize its configuration and appearance.It was observed that the size of nano paticle was about 50-60 nm.As model compound,methylene blue was used to investigate photocatalytic degradation of Fe-Ag/NT.Calcining temperpature,content of Fe-Ag/NT and reaction time were examined.It was proved that its absorbance scope was brodened to about 500 nm and photic absorbance intensity was increased to about 1.4 a.u.because of adding of Fe3 + and Ag.Its photocatalytic activity to MB(10 mg/L) reached 93.2%under the best conditions(calcining temperpature:700 ^C;content of Fe-Ag/NT:50 mg;reaction time:6 h),which was 2.14 times than that of pure TiO2.Composited Nano-TiO2 impured by Fe-Ag double element has much more photocatalytic activity than those impured by single element. In chapter 3,MPS-Fe-Ag/NT was obtained after surface modifacition of Fe-Ag/NT by MPS.Then it was characterized by FT-RI and TEM.Preparation process of nano fluorin carbon latex was studied.It was shown that the surface of Fe-Ag/NT was modified by MPS successfully and MPS-Fe Ag/NT was dispersed evenly in the system.Latex particles with Core(MPS-Fe-Ag/NT)-Shell(polymer) structure was formed in nano fluorin carbon latex under the best conditions(polymerization temperpature:85℃;milling intensity:200 rpm;content of emulsification:2.5%; content of MPS-Fe-Ag/NT:3.0%).General performances of latex were above excellent grade accoding to GB/T 9756-2001.Capability of antibacterial to Staphylococcus and Escherichia coli was above the first class accoding to HG/T 3950-2007.Water contact angle of dry film was 135°.It was fit for coating building inner wall for excellent self-cleaning function.In chapter 4,nano fluorin carbon coating with self-cleaning function and antibacterial capability was prepared by FC/MPS-Fe-Ag/NT which was used as the prime membrane-forming substance as well as other pigments and fillings.General performances and capability of antibacterial to Staphylococcus and Escherichia coli were tested by advanced instruments.The mechanism of antibacterial and self-cleaning function was discussed.As a result,the performances of coating were fit for the standard of synthetic resin latex inner coating according to GB/T 9756-2001. Capability of antibacterial to Staphylococcus and Escherichia coli was above the first class accoding to HG/T 3950-2007.The surface of nano fluorin carbon coating with hydrophobic function had strong water-resistance and smirch-resistance.It has excellent self-cleaning function.Study and development of waterborne nano fluorin carbon coating with self-cleaning function and antibacterial capability broaden the new variety of antibacterial coatings.The thesis broadened the latency application of nano-TiO₂ accoding to configuration and surface modification.The dispersant of nano particles in latex was achieved.The successful prepatation of waterborne nano fluorin carbon coating with self-cleaning function and antibacterial capability provided theory base and preparation method for obtaining safe,.wide range and perdurable nano self-cleaning antibacterial fluorin carbon coating.It displayed new method for solving inner air pollution.Theoretically and realistically,it is very significant for removing inner nocuousness gas,limiting pathogenic microorganism,improving living and working surroundings and increasing human health.