The polymerization of acrylonitrile (AN) in aqueous nitric acid initiated by metavanadate-containing anion exchange resin (PV)-thiourea (TU) redox system at 20—40℃. has been investigated. The overall rate of polymer...The polymerization of acrylonitrile (AN) in aqueous nitric acid initiated by metavanadate-containing anion exchange resin (PV)-thiourea (TU) redox system at 20—40℃. has been investigated. The overall rate of polymerization (R_p) is given byR_p=1.92×10~4e^(-6.860/RT) [AN]^(1.2) [PV]^(0.44) [TU]^(1.0)[HNO_3]^(1.0)The kinetic parameters differed from those of V^(5+)-TU system indicated that the generation of the primary radicals is mainly a difffusion-controlled reaction. The effect of macromolecular field arisen from the polymer matrix exerts a great influence on the polymerization process.展开更多
The effects of N-2-hydroxyethyl-N-methyl-p-toluidine (HMT) on MMA polymerization using organic peroxide as an initiator and on AN photoinduced polymerization have been investigated respectively. The kinetics of polyme...The effects of N-2-hydroxyethyl-N-methyl-p-toluidine (HMT) on MMA polymerization using organic peroxide as an initiator and on AN photoinduced polymerization have been investigated respectively. The kinetics of polymerization and the overall activation energy of polymerization were determined. Based on kinetics study and the end group analysis of the polymer obtained by UV spectrum method, the initiation mechanism is proposed.展开更多
The emulsion polymerization of N-phenylmaleimide, Styrene and acrylonitrile was studied. The thermal property of this copolymer was measures by dynamic thermomechanical analysis(DMA). The mechanical properties, such a...The emulsion polymerization of N-phenylmaleimide, Styrene and acrylonitrile was studied. The thermal property of this copolymer was measures by dynamic thermomechanical analysis(DMA). The mechanical properties, such as tensile strength, hardness and fie-cural Strength were StUdied experimentally. The results indicated that not only the monomer component but also the polymerization technologies have effect on the properties of the copolymer. The optimum monomer content and suitable polymerization method were obtained.展开更多
The initiation mechanism of acrylamide (AAM)polymerization using ceric ion/acetylacetone system as an initiator has been studied. The redox polymerization was revealed by the low value of overall activation energy of ...The initiation mechanism of acrylamide (AAM)polymerization using ceric ion/acetylacetone system as an initiator has been studied. The redox polymerization was revealed by the low value of overall activation energy of AAm polymerization. The structure of free radicals formed from above-mentioned initiation sytem were detected by radical trapping and ESR spectra techniques and the end groups of polymers obtained were determined by FT-IR spectra analysis method. Based on these results the initiation mechanism is proposed.展开更多
The polymerization of acrylamide (AAM)in H_2O/DMF or in H_2O/CH_3CN mixed solvent initiated with ceric ion (Ce^(4+) )/N-(substituted phenyl)-acetamide systems have been studied. The redox polymerization was revealed b...The polymerization of acrylamide (AAM)in H_2O/DMF or in H_2O/CH_3CN mixed solvent initiated with ceric ion (Ce^(4+) )/N-(substituted phenyl)-acetamide systems have been studied. The redox polymerization was revealed by the low value of overall activation energy (E_α) of AAM polymerization using ceric ion/N-(substituted phenyl) acetamide system as an initiator. The end group of polymer formed was detected by IR spectrum analysis method, it revealed the presence of N-(m-acetoxy-methylphenyl) acetamide (m-AAe) moiety end group in the polymer obtained with ceric ion/m-AAe initiation system.展开更多
The reaction between K(1 C 5H 9C 9H 6) and anhydrous LnCl 3 (Ln=Sm, Yb) in the molar ratio of 2∶1 in THF with subsequent treatment by Na K alloy afforded (1 C 5H 9C 9H 6) 2Ln (THF) n (Ln=Sm, n =...The reaction between K(1 C 5H 9C 9H 6) and anhydrous LnCl 3 (Ln=Sm, Yb) in the molar ratio of 2∶1 in THF with subsequent treatment by Na K alloy afforded (1 C 5H 9C 9H 6) 2Ln (THF) n (Ln=Sm, n =1; Ln=Yb, n =2), while the reaction of SmI 2 with K(1 C 5H 9C 9H 6) in the molar ratio of 1∶2 in THF gave the anionic complex K(1 C 5H 9C 9H 6) 3Sm(THF) 3. The X ray structure of (1 C 5H 9C 9H 6) 2Yb(THF) 2 showed that central metal Yb is coordinated by two cyclopentadienyl rings of 1 cyclopentylindenyls and two oxygen atoms from two tetrahydrofuran molecules to form pseudo tetrahedral coordinate geometry. All these complexes are active for the polymerization of acrylonitrile.展开更多
The photopolymerization of acrylonitrile (AN) initited by aromatic tertiary amine, phenothiazine, diphenylsulfide triphenylphosphine, etc. are known to proceed by a charge transfer process with the formation of an exc...The photopolymerization of acrylonitrile (AN) initited by aromatic tertiary amine, phenothiazine, diphenylsulfide triphenylphosphine, etc. are known to proceed by a charge transfer process with the formation of an exciplex. Recently we have briefly reported that the N-vinylcarbazole (VCZ) is an excellent photoinitiator for AN polymeriza-展开更多
文摘The polymerization of acrylonitrile (AN) in aqueous nitric acid initiated by metavanadate-containing anion exchange resin (PV)-thiourea (TU) redox system at 20—40℃. has been investigated. The overall rate of polymerization (R_p) is given byR_p=1.92×10~4e^(-6.860/RT) [AN]^(1.2) [PV]^(0.44) [TU]^(1.0)[HNO_3]^(1.0)The kinetic parameters differed from those of V^(5+)-TU system indicated that the generation of the primary radicals is mainly a difffusion-controlled reaction. The effect of macromolecular field arisen from the polymer matrix exerts a great influence on the polymerization process.
基金The project supported by the National Natural Science Foundation of China
文摘The effects of N-2-hydroxyethyl-N-methyl-p-toluidine (HMT) on MMA polymerization using organic peroxide as an initiator and on AN photoinduced polymerization have been investigated respectively. The kinetics of polymerization and the overall activation energy of polymerization were determined. Based on kinetics study and the end group analysis of the polymer obtained by UV spectrum method, the initiation mechanism is proposed.
文摘The emulsion polymerization of N-phenylmaleimide, Styrene and acrylonitrile was studied. The thermal property of this copolymer was measures by dynamic thermomechanical analysis(DMA). The mechanical properties, such as tensile strength, hardness and fie-cural Strength were StUdied experimentally. The results indicated that not only the monomer component but also the polymerization technologies have effect on the properties of the copolymer. The optimum monomer content and suitable polymerization method were obtained.
基金The project was supported by the National Natural Science Foundation of China
文摘The initiation mechanism of acrylamide (AAM)polymerization using ceric ion/acetylacetone system as an initiator has been studied. The redox polymerization was revealed by the low value of overall activation energy of AAm polymerization. The structure of free radicals formed from above-mentioned initiation sytem were detected by radical trapping and ESR spectra techniques and the end groups of polymers obtained were determined by FT-IR spectra analysis method. Based on these results the initiation mechanism is proposed.
基金The project supported by the National Natural Science Foundation of China
文摘The polymerization of acrylamide (AAM)in H_2O/DMF or in H_2O/CH_3CN mixed solvent initiated with ceric ion (Ce^(4+) )/N-(substituted phenyl)-acetamide systems have been studied. The redox polymerization was revealed by the low value of overall activation energy (E_α) of AAM polymerization using ceric ion/N-(substituted phenyl) acetamide system as an initiator. The end group of polymer formed was detected by IR spectrum analysis method, it revealed the presence of N-(m-acetoxy-methylphenyl) acetamide (m-AAe) moiety end group in the polymer obtained with ceric ion/m-AAe initiation system.
文摘The reaction between K(1 C 5H 9C 9H 6) and anhydrous LnCl 3 (Ln=Sm, Yb) in the molar ratio of 2∶1 in THF with subsequent treatment by Na K alloy afforded (1 C 5H 9C 9H 6) 2Ln (THF) n (Ln=Sm, n =1; Ln=Yb, n =2), while the reaction of SmI 2 with K(1 C 5H 9C 9H 6) in the molar ratio of 1∶2 in THF gave the anionic complex K(1 C 5H 9C 9H 6) 3Sm(THF) 3. The X ray structure of (1 C 5H 9C 9H 6) 2Yb(THF) 2 showed that central metal Yb is coordinated by two cyclopentadienyl rings of 1 cyclopentylindenyls and two oxygen atoms from two tetrahydrofuran molecules to form pseudo tetrahedral coordinate geometry. All these complexes are active for the polymerization of acrylonitrile.
文摘The photopolymerization of acrylonitrile (AN) initited by aromatic tertiary amine, phenothiazine, diphenylsulfide triphenylphosphine, etc. are known to proceed by a charge transfer process with the formation of an exciplex. Recently we have briefly reported that the N-vinylcarbazole (VCZ) is an excellent photoinitiator for AN polymeriza-
