Nano-PET Biocatalytic Decomposition Research

At present,PET biocatalytic degradation has been extended from the traditional small molecule as substrate to the biodegradation of polymer as substrate.Biocatalysis decomposition is more thorough,and the degradation of PET can be achieved through biocatalysis,which can degrade the product of harmful organics into small molecules,such as CO2 and H2O,which are harmless to human body.However,the fragmentation of polymer from the surface of the polymer is the lowest efficiency step in the process and the bottleneck of the whole process.Based on the laboratory breeding to PET as the sole carbon source of PET decomposition microbes for starting strain,with the evolution of engineering method,the breeding of alkali resistance of PET decomposition microbes,as whole-cell biocatalyst,investigation under the combined chemical and biological PET micron particle treatment effect,build the difficult to deal with the combination of high polymer processing technology.HPLC was used to analyze the changes of the decomposition products,monitored the changes of biomass,tested the changes of the substrate size,and characterized the changes of the PET morphological structure of the substrate by SEM,DSC and FTIR.Found the whole cell biology catalytic decomposition of PET product changes over time and the characteristics of the product quantity decrease,under the condition of alkaline cell biology catalytic decomposition of PET products is not the product of the neutral condition also have obvious diference.Monitoring biomass compared with single biological treatment,the biochcemical composition when the PET as the sole carbon source under the condition of the growth of strains,delay shortened obviously,after the transfer of the early growth speed faster,the OD value of the biggest biomass logarithmic phase can be up to 0.35;'The particle size distribution of PET micron particles in the neutral condition was concentrated under the condition of alkaline whole cell biocatalysis,and the mean particle size was reduced from 7.3?m to 1.58?m.Preparation of the nanometer level using ultrasonic chemical precipitation PET nanoparticles,using polyethylene terephthalate as raw materials,six fluorine isopropyl alcohol as solvent,and using laser scattering particle size analyzer,SEM and DSC experiment means such as the raw materials and the preparation of the samples were characterized by analysis.A stable PET suspension solution with an average particle size of 90nm was prepared.The thermal properties of polyester nanoparticles were analyzed by DSC,and the crystallinity decreased by 7.92%.Prepared PET nanoparticles as the substrate,used to PET as the sole carbon source for growth of bacteria culture,studying the effect of nanometer structure substrates on bacteria growth,monitoring of substrates in biocatalysis product in the process of change,and detect the substrate itself structure and performance in the change of the biological catalysis process,this research nano substrate interact with biological catalysis system,study the process of PET biocatalysis nano effect.The study found that the biomass of nanometer PET substrate was higher than that of the micron PET.The biological decomposition products of nano-pet particles and micron PET particles are the same,but the same products are produced with nanometersubstrate and the production of substrate is higher than that of the substrate.Nanometer PET and micron PET as substrate,due to the influence of biological factors will show different particle size performance.The DSC test showed that the crystallinity of the treatment was improved after treatment.