Immobilization Of Thermoresponsive Polymers And Laccase On TiO₂ Nanoparticles Via Novel Controlled Radical Polymerization

The nano-TiO2 particles/temperature-sensitive polymers were prepared by grafting step by step and the "one-pot method".Through the temperature control,the effect of nanocomposites dispersed well in water to agglomeration of particles was investigated.On the basis of this,immobilization of laccase and the study on the degradation of pollutants by this dual catalysis material were carried out.The specific research contents are as follows:(1)Monomer di(ethylene glycol)ethyl ether acrylate(DEGEEA)and poly(ethylene glycol)methyl ether acrylate(PEGA480)were prepared for copolymerization from unprotected dopamine functionalized initiators using Cu(0)mediated living radical polymerization(Cu(0)-LRP),and the copolymerization of N-isopropylacrylamide(NIPAM)and glycidyl acrylate(GA)to synthesize temperature-sensitive polymers with different structures and low critical solution temperature(LCST).Through NMR and GPC analyzes,these temperature-sensitive polymers can be completely or nearly completely converted in minutes at room temperature or below.(2)The temperature-sensitive polymers poly(DEGEEA)-r-(PEGA480)and poly(NIPAM)-r-(GA)were grafted onto the surface of nano-TiO2 particles by "grafting to".The structure and composition of the polymerization product and the grafted product were characterized and detected by Fourier transform infrared spectroscopy(FTIR),thermogravimetric analysis(TGA)and transmission electron microscopy(TEM).Laccase immobilization was achieved on the basis of nanometer TiO2@poly(NIPAM)-r-(GA)hybrid material.The FTIR,TGA,TEM,TEM and fluorescence spectroscopy confirmed the structure and composition of the final material TiO2@ poly(NIPAM)-r-(GA)@Laccase.(3)TiO2@poly(DEGEEA)-r-(PEGA480)nanohybrids and Ti02@poly(NIPAM)-r-(GA)@Laccase self-flocculation and photocatalytic degradation experiments in water,through the temperature control switch material to achieve the performance of the photocatalytic performance of the open and close and diastolic dissolution and self-flocculation of the mutual transformation.In the degradation of dyes Rhodamine B and bisphenol A experiments,to achieve more than 90%removal rate,and has a good recycling effect.(4)The preparation of Cu(0)-LRP nanosized TiO2/thermo-sensitive polymer hybrid material by the "one-pot" saves the time of step-by-step preparation.The NMR and GPC analysis show that the conversion rates exceed 90%.