Research On The Preparation Of PDAC With High And Serial Molecular Weight

Acryloyloxyethyl trimethyl ammonium chloride?DAC?is a water-soluble cationic monomer with special functions.Its polymerized product can be widely used in petroleum extraction,paper-making,water treatment and other fields.Moreover,the amount demand on this polymer is annually increasing.The research on polymerization process based on DAC is mostly concentrated on the field of copolymerization,while the homopolymer of DAC is still not widely studied.A new polymerization process of poly-acryloyloxyethyl trimethyl ammonium chloride?PDAC?using aqueous solution polymerization was studied in this paper,and the polymerization processes of PDAC using azobis isobutyl amidine hydrochloride?V50?and ammonium persulfate?APS?as initiators were investigated,respectively.The processing conditions of PDAC with high molecular weight were obtained,and a controlled polymerization method of PDAC with high monomer conversion and serial molecular weight was further studied.The research results will lay the foundation for the further research on the processing optimization and industrial application of PDAC.The preparation of PDAC with high molecular weight was studied,using industrial monomer of acryloyloxyethyl trimethyl ammonium chloride?DAC?as the raw material,tetrasodium Na₄EDTA as the chelator,and using the method of adding initiator all at once and two-step increasing of temperature for aqueous polymerization.The polymerization processes of PDAC using azobis isobutyl amidine hydrochloride?V50?and ammonium persulfate?APS?were studied,respectively.The influencing factors such as the mass fraction of monomer w?DAC?,the amount of initiator m?I?:m?DAC?,the amount of additives m?Na₄EDTA?:m?DAC?,the initiation temperature T₁,the curing temperature T₂ and the reaction time were also investigated.The optimal processing conditions of PDAC under two initiator systems were obtained by orthogonal experiment respectively.The influence of each factor on the intrinsic viscosity and monomer conversion of PDAC was also studied.The results showed that the optimal polymerization processing parameters of PDAC using azobis isobutyl amidine hydrochloride?V50?as the initiator were w?DAC?of 53%,w?V50?:m?DAC?and m?Na₄EDTA?:m?DAC?were 0.225%and 0.02%respectively,under the conditions of the polymerization initiation temperature T₁ at 43 ?,then curing temperature T₂ at 60 ?,each step for 3h.Under these conditions,the intrinsic viscosity of the product was 14.16 dL/g and the monomer conversion was 98.56%;the optimal polymerization processing parameters of PDAC using ammonium persulfate?APS?as the initiator were w?DAC?of 53%,m?APS?;m?DAC?and m?Na4EDTA?:m?DAC?were 0.50%and 0.01%respectively,under the condition of the polymerization initiation temperature T₁ at 46 ?,then curing temperature T₂ at 60 ?.each step for 3h.Under these conditions,the intrinsic viscosity of the product was 12.49dL/g and the monomer conversion was 98.66%.Both of the intrinsic viscosity of PDAC product exceeded the maximum value which has been reported in the literature until now.The structures of the products were characterized by FTIR and ¹HNMR.The controlled polymerization process of PDAC with high monomer conversion and serial molecular weight was studied.On the basis of the polymerization process of PDAC with high molecular weight using APS initiator as mentioned above,and according to the method of controlled polymerization of poly-dimethyldiallyl ammonium chloride,without any transferring and inhibiting agents added,the series of PDAC products with intrinsic viscosities range from about 2.00 to 12.00dL/g and monomer conversion more than 98.00%could be obtained by using a method of only controlling the mass fraction of monomer?w?DAC?= 25.0%?53.0%?and the amount of initiator?m?APS?:m?DAC?= 0.5%?15.0%?.The controllable polymerization of PDAC products with serial molecular weight was established and this method has not been reported in the literature yet,until now.The structures of series PDAC products were characterized by FTIR and 'HNMR,and their molecular weights were measured by gel permeation chromatography?GPC?.The method is simple,and stable,and the results will provide a basis for the polymerization and its application of PDAC with serial molecular weights.