The initiation mechanism of methyl methacrylate (MMA) polymerization by organic peroxide and polymerizable aromatic tertiary amine such as N-methacryloyloxyethyl-N-methyl aniline (MEMA) binary system has been studied....The initiation mechanism of methyl methacrylate (MMA) polymerization by organic peroxide and polymerizable aromatic tertiary amine such as N-methacryloyloxyethyl-N-methyl aniline (MEMA) binary system has been studied. The kinetics of polymerization of MMA and the ESR spectra of organic peroxide/MEMA system were determined. Based on the ESR study and the end-group analysis by UV spectra of the polymer formed, the initiation mechanism is proposed.展开更多
Acrylamide polymerization initiated with a redox initiation system consisting of eerie ion and ethyl N,N-diethyldithiocarbamyl acetate (EDCA) has been studied. It was found that the polymerization rate equation is in ...Acrylamide polymerization initiated with a redox initiation system consisting of eerie ion and ethyl N,N-diethyldithiocarbamyl acetate (EDCA) has been studied. It was found that the polymerization rate equation is in good agreement with that of a redox initiated polymerization, and the overall activation energy of the polymerization was determined to be 25.2 kJ.mol(-1). Accordingly, the system belongs to a redox initiator. The initiation mechanism was proposed based on the end group analysis using FT-IR, UV spectroscopies. Analysis results revealed that the N, N-diethyldithiocarbamyl radical produced from the redox reaction of EDCA with eerie ion can initiate acrylonitrile (AN) polymerization and form the end group on PAN. The resulting PAN was photopolymerized with butyl acrylate (BE) to form PAN-b-PBA block copolymer.展开更多
The homopolymerization of 5-methyl-5-hexen-2,4-dione (methacryloylacetone, MAA), a vinyl monomer having beta-diketone group, was carried out in the presence of benzophenone (BP)/N, N-dimenthyl-4-toluidine (DMT) system...The homopolymerization of 5-methyl-5-hexen-2,4-dione (methacryloylacetone, MAA), a vinyl monomer having beta-diketone group, was carried out in the presence of benzophenone (BP)/N, N-dimenthyl-4-toluidine (DMT) system. Graft polymerization of acrylamide initiated by eerie ion onto the homopolymer film was investigated and the mechanism of the grafting reaction was proposed on the basis of ESR study. The grafted copolymer was characterized by means of grafting percentage, water absorption, XPS spectra and scanning electron photomicrographs.展开更多
The redox initiation system for polyacrylate sodium of high molecular mass was designed and its effect with varying component dosage on the degree of polymerization was investigated. The results show that the proper t...The redox initiation system for polyacrylate sodium of high molecular mass was designed and its effect with varying component dosage on the degree of polymerization was investigated. The results show that the proper type and amount of inorganic salt, as well as amine initiator, are conductive to the increase of degree of polymerization. The fine ingredient of the initiation system is as follows:the dosages of amine, persulphate and inorganic salt are 0.75%, 0.10% and 1.00% by mass based on acryl acid respectively, the molar ratio of sulphite to the persulphate is 1:1. Under such conditions the degree of polyacrylate can reach 7.43×107 with a acceptable polymerization time for industrial production.展开更多
The kinetics of acrylamide (AAM) polymerization initiated by diperiodatonickelate(Ⅳ) periodate complex was studied in aqueous alkaline medium.The results indicate that the equation of the polymerization rate is as fo...The kinetics of acrylamide (AAM) polymerization initiated by diperiodatonickelate(Ⅳ) periodate complex was studied in aqueous alkaline medium.The results indicate that the equation of the polymerization rate is as follows:R p=k[Ni(Ⅳ)] 0 72 [AM] 1 41 and the overall activation energy of AAM polymerization is 41 33kJ/mol.The polymer molecular weight decreases with increasing [Ni(Ⅳ)] and increases with increasing [AAM].The effects of various reaction conditions on the polymerization rate were also studied.The initiation mechanism was proposed.展开更多
基金Project supported by the National Natural Science Foundation of China
文摘The initiation mechanism of methyl methacrylate (MMA) polymerization by organic peroxide and polymerizable aromatic tertiary amine such as N-methacryloyloxyethyl-N-methyl aniline (MEMA) binary system has been studied. The kinetics of polymerization of MMA and the ESR spectra of organic peroxide/MEMA system were determined. Based on the ESR study and the end-group analysis by UV spectra of the polymer formed, the initiation mechanism is proposed.
基金The Project 29234093 was supported by the National Natural Science Foundation of China.
文摘Acrylamide polymerization initiated with a redox initiation system consisting of eerie ion and ethyl N,N-diethyldithiocarbamyl acetate (EDCA) has been studied. It was found that the polymerization rate equation is in good agreement with that of a redox initiated polymerization, and the overall activation energy of the polymerization was determined to be 25.2 kJ.mol(-1). Accordingly, the system belongs to a redox initiator. The initiation mechanism was proposed based on the end group analysis using FT-IR, UV spectroscopies. Analysis results revealed that the N, N-diethyldithiocarbamyl radical produced from the redox reaction of EDCA with eerie ion can initiate acrylonitrile (AN) polymerization and form the end group on PAN. The resulting PAN was photopolymerized with butyl acrylate (BE) to form PAN-b-PBA block copolymer.
基金The project was supported by the National Natural Science Foundation of Chna.
文摘The homopolymerization of 5-methyl-5-hexen-2,4-dione (methacryloylacetone, MAA), a vinyl monomer having beta-diketone group, was carried out in the presence of benzophenone (BP)/N, N-dimenthyl-4-toluidine (DMT) system. Graft polymerization of acrylamide initiated by eerie ion onto the homopolymer film was investigated and the mechanism of the grafting reaction was proposed on the basis of ESR study. The grafted copolymer was characterized by means of grafting percentage, water absorption, XPS spectra and scanning electron photomicrographs.
基金Project(G199906490 2) supported by the National Key Fundamental Research and Development Program of China
文摘The redox initiation system for polyacrylate sodium of high molecular mass was designed and its effect with varying component dosage on the degree of polymerization was investigated. The results show that the proper type and amount of inorganic salt, as well as amine initiator, are conductive to the increase of degree of polymerization. The fine ingredient of the initiation system is as follows:the dosages of amine, persulphate and inorganic salt are 0.75%, 0.10% and 1.00% by mass based on acryl acid respectively, the molar ratio of sulphite to the persulphate is 1:1. Under such conditions the degree of polyacrylate can reach 7.43×107 with a acceptable polymerization time for industrial production.
文摘The kinetics of acrylamide (AAM) polymerization initiated by diperiodatonickelate(Ⅳ) periodate complex was studied in aqueous alkaline medium.The results indicate that the equation of the polymerization rate is as follows:R p=k[Ni(Ⅳ)] 0 72 [AM] 1 41 and the overall activation energy of AAM polymerization is 41 33kJ/mol.The polymer molecular weight decreases with increasing [Ni(Ⅳ)] and increases with increasing [AAM].The effects of various reaction conditions on the polymerization rate were also studied.The initiation mechanism was proposed.
