Ternary Polymerization Of Cationic Polyacrylamide Initiated By Ultraviolet Light And Photosencitizer And Dertermine Of Reaction Mechanism

With the development of society and growing public environmental awareness,wast water treatment is attracting a great amount of attention.Among the different dealing methods,flocculation is widely used both in China and other areas because of its characteristics of low cost and broad usage.Organic and inorganic high-polymer flocculating agent are the main choices among all the flocculating agent products.Cationic flocculating agent is a kind of organic flocculating agent,it has the function of charge neutralization,absorption and bridge,which make it easier to remove the colloidal particles and pollutants.As a result Cationic flocculants is a hot destination of water treatment chemicals researches.Cationic polyacrylamide is a kind of ramification of polyacrylamide.It has the advantage of high molecular weight,soft molecular chain,high density of positive charge and good solubility etc.Modification and copolymerization are 2 main method to produce Cationic polyacrylamide.Modification includes Hofinann degradation,amino methylation and Mancini reaction,products prepared by these ways has the disadvantage of low molecular weight and difficult to manufacture.Traditional copolymerization is heat-initiated binary-copolymerization of acrylamide and canonic monomer,which has shortcoming of high starting temperature,less energy efficient.Photo-initiated copolymerization is a new technology,which is environmental friendly,well-producted and easily operated,meanwhile ternary copolymerization solve the problem of high cost and uncontrollability.In this paper V-50 and ultraviolet ray were used to initiated the reaction in aqueous solution to manufacture the ternary copolymer product of canonic polyacrylamide P(DMC-AM-DAC).During the experiment,best reaction condition was determined,in which light strength is 0.656mw·cm-2,photo initiator concentration is 0.175g/L,monomer concentration is 350g/L,n(DMC):n(DAC):n(AM)=6:14:80,starting temperature is 21 ℃,concentration of additive I is 0.5g/L,concentration of additive II is 255mg/L and pH=6.Under the best condition,products of high quality was manufactured.The product has the molecular of over 13 million,its dissolve time is than 30 minutes,canonic degree is more than 16%,solid content is over 95%,monomer remain is less than 0.08%.Its excellent performance was proved by the comparison experiment.Each of the 2 canonic monomer was copolymerized with acrylamide,under the low conversion state,reactivity ratio and kinetics were studied respectively.By comparing the data of the study,performance of the 3 monomer in ternary polymerization was analyzed,which provided the theoretical and practical basis to the future industrial production.Based on the technique of photo-initiated polymerization,a new type of CPAM producing equipment was designed.The material of equipment is stainless steel.Inside the equipment there are reacting container and ultraviolet racecourse,whose height can be controlled.Viewing port and-sealing device is also on the equipment,make it safe and easily controlled.The new type of CPAM producing equipment is beautifully presented and also has the advantage of large output,low energy cost and easily operated.It is suitable for the industrial production.