Copolymerization of styrene (St) with N-phenylmaleimide (NPMI) was studied with rare earth coordination catalyst Nd(naph)3-AlEt3 in toluene. Characterization of the copolymers showed that the copolymers possess an al...Copolymerization of styrene (St) with N-phenylmaleimide (NPMI) was studied with rare earth coordination catalyst Nd(naph)3-AlEt3 in toluene. Characterization of the copolymers showed that the copolymers possess an alternating structure.展开更多
A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-g...A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-glutamate(SLG) NCA using neodymium acetylacetonate (Nd(acac)_3)- or neodymium tris(2-ethylhexylphosphonate) (Nd(P_(204))_3)-triethylaluminum-water as catalysts were compared with those using conventional catalysts. It was found that the helicalpoly(γ-stearyl-L-glutamate) with high molecular weight as well as narrow molecular weight distribution can be obtained inthe presence of Nd(acac)_3/AlEt_3-1/2H_2O. The polymer obtained was characterized by IR and NMR spectroscopy.展开更多
The polymerization of 1-octene with Nd(P_(204))_3-AlEt_3 catalyst has been successfully carried out for the first time.Some features of polymerization of 1-octene are described.The 1-octene oligomer prepared has an av...The polymerization of 1-octene with Nd(P_(204))_3-AlEt_3 catalyst has been successfully carried out for the first time.Some features of polymerization of 1-octene are described.The 1-octene oligomer prepared has an average molecular weight of about 10~3 with molecular weight distribution of about 2.It has a terminal double bond,which can be transferred into terminal carboxy group by direct oxidation with KMnO_4 in acidic solution, and then can be esterified with polyglycol.展开更多
Polymerization of 4-vinylpyridine was carried out with the lanthanide coordination catalyst. The influence of the component in catalytic system and solvents had been examined. The molecular weight of poly(4-vinylpyr...Polymerization of 4-vinylpyridine was carried out with the lanthanide coordination catalyst. The influence of the component in catalytic system and solvents had been examined. The molecular weight of poly(4-vinylpyridine) obtained in CH2Cl2 with Ln(P204)3 /Al(i-Bu)3 is more than 20104.展开更多
Copolymerization of carbon dioxide with epichlorohydrin was successfully carried out by usingNd(P_(204))_3-Al(i-Bu)_3 as catalyst (P_(204))=(RO)_2 POO--,R=CH_3 (CH_2),CH(C_2H_5) CH_2--). Addi-tion of carbonyl compound...Copolymerization of carbon dioxide with epichlorohydrin was successfully carried out by usingNd(P_(204))_3-Al(i-Bu)_3 as catalyst (P_(204))=(RO)_2 POO--,R=CH_3 (CH_2),CH(C_2H_5) CH_2--). Addi-tion of carbonyl compounds into the catalyst decreased the carbon dioxide content of the copoly-mer to some extent. Compared to nonpolar solvents, ethereal and moderate polar solvents werefavourable to obtaining higher carbon dioxide content copolymer. The coincidence of these resultswith the assumed copolymerization scheme clearly indicated that the copolymerization proceeds via coordinate anionic mechanism.展开更多
基金This project was supported by the National Natural Science Foundation of China. (No.29974024,20254001)
文摘Copolymerization of styrene (St) with N-phenylmaleimide (NPMI) was studied with rare earth coordination catalyst Nd(naph)3-AlEt3 in toluene. Characterization of the copolymers showed that the copolymers possess an alternating structure.
基金This work was supported by National Natural Science Foundation of China (No. 29504029).
文摘A rare earth coordination system was first investigated as a new type of catalyst for the ring-openingpolymerization of α-amino acid N-carboxyanhydrides (NCAs). The results for the polymerization of γ-stearyl-α,L-glutamate(SLG) NCA using neodymium acetylacetonate (Nd(acac)_3)- or neodymium tris(2-ethylhexylphosphonate) (Nd(P_(204))_3)-triethylaluminum-water as catalysts were compared with those using conventional catalysts. It was found that the helicalpoly(γ-stearyl-L-glutamate) with high molecular weight as well as narrow molecular weight distribution can be obtained inthe presence of Nd(acac)_3/AlEt_3-1/2H_2O. The polymer obtained was characterized by IR and NMR spectroscopy.
文摘The polymerization of 1-octene with Nd(P_(204))_3-AlEt_3 catalyst has been successfully carried out for the first time.Some features of polymerization of 1-octene are described.The 1-octene oligomer prepared has an average molecular weight of about 10~3 with molecular weight distribution of about 2.It has a terminal double bond,which can be transferred into terminal carboxy group by direct oxidation with KMnO_4 in acidic solution, and then can be esterified with polyglycol.
文摘Polymerization of 4-vinylpyridine was carried out with the lanthanide coordination catalyst. The influence of the component in catalytic system and solvents had been examined. The molecular weight of poly(4-vinylpyridine) obtained in CH2Cl2 with Ln(P204)3 /Al(i-Bu)3 is more than 20104.
文摘Copolymerization of carbon dioxide with epichlorohydrin was successfully carried out by usingNd(P_(204))_3-Al(i-Bu)_3 as catalyst (P_(204))=(RO)_2 POO--,R=CH_3 (CH_2),CH(C_2H_5) CH_2--). Addi-tion of carbonyl compounds into the catalyst decreased the carbon dioxide content of the copoly-mer to some extent. Compared to nonpolar solvents, ethereal and moderate polar solvents werefavourable to obtaining higher carbon dioxide content copolymer. The coincidence of these resultswith the assumed copolymerization scheme clearly indicated that the copolymerization proceeds via coordinate anionic mechanism.
