Experimental Study On The Synthesis Of Polycaprolactones By Lipase Catalysis

As a new type of material,polycaprolactone has received wide attention from all walks of life because it has many properties that other materials cannot match.The synthesis of polycaprolactone has become a research hotspot of researchers in recent years.Many synthetic methods have been reported,but chemical synthesis has metal toxicity and causes environmental pollution and waste of resources.However,the enzyme-catalyzed method is compared with it.The conditions are much milder,and the catalyst can be recycled for multiple uses,and the operability is strong.This paper mainly explores the influence of various factors on the system from the perspective of biocatalysis,and finally determines the best experimental scheme.In this paper,the reaction system was explored from the aspects of catalyst type,amount of catalyst,type of solvent,form of oxidant,ratio of cyclohexanone to hydrogen peroxide,reaction temperature and reaction time.The main conversion rate of cyclohexanone was tested.The yield of polycaprolactone and the molecular weight of polycaprolactone vary with factors.Finally,the single factor test and response surface optimization are used to determine the catalysis of 50.1mg Novozym435 with toluene as solvent and anhydrous urea hydrogen peroxide as oxidant.The ratio of cyclohexanone to hydrogen peroxide is 1:2,the reaction temperature is 49.6 ?,and the reaction is 20.1 h to achieve the best experimental results: cyclohexanone conversion rate is 86.5%,polycaprolactone yield is 66.1%,the molecular weight of polycaprolactone(Mn) is 2912.