Preparation of an amphiphilic graft copolymer having poly(phthalazinone ether sulfone ketone)(PPESK) as main chains was carried out by atom transfer radical polymerization(ATRP).The precursor,chloromethylated PPESK (C...Preparation of an amphiphilic graft copolymer having poly(phthalazinone ether sulfone ketone)(PPESK) as main chains was carried out by atom transfer radical polymerization(ATRP).The precursor,chloromethylated PPESK (CMPPESK),was prepared by using chioromethylether as chloromethylation agent.Then,poly(ethylene glycol) methyl ether methacrylate(PEGMA) was used as monomer to synthesize PPESK-g-P(PEGMA) by ATRP method under the catalysis of a cuprous chloride/2,2'-bipyridyl system.PPESK/PPESK-g-P(PEGMA) blend m...展开更多
An efficient route to macrocyclic polymers via “click” cyclization was presented.The α-bromine and ω-alkyne PMMA were prepared using the standard ATRP technique,initiated with propargyl 2-bromoisobutyrate,Cu(Ⅰ)Br...An efficient route to macrocyclic polymers via “click” cyclization was presented.The α-bromine and ω-alkyne PMMA were prepared using the standard ATRP technique,initiated with propargyl 2-bromoisobutyrate,Cu(Ⅰ)Br and N,N,N’,N″,N-pentamethyldiethylenetriamine(PMDETA).Azidation of the terminal bromine was followed in DMF with sodium azide,and α-azide,ω-alkyne PMMA precursor was obtained.Then the “click” cylcization of precursor between terminal azide and alkyne was carried out under the catalysis of CuBr/PMDETA,during the course of the reaction,a pseudo-high dilution technique was utilized to ensure the favored intramolecular cylcization.The nearly complete cylcization has been confirmed by a combination of IR,1H NMR and GPC analysis,and cyclo-PMMA with an Mn of 15000,PDI of 1.38 was obtained.展开更多
A new approach to the synthesis of dendrimer-like star polymer,[(PMMA)2PSt]4,was presented via the combination of atom transfer radical polymerization(ATRP) and ckick chemistry.Firstly four-arm bromine-terminated poly...A new approach to the synthesis of dendrimer-like star polymer,[(PMMA)2PSt]4,was presented via the combination of atom transfer radical polymerization(ATRP) and ckick chemistry.Firstly four-arm bromine-terminated polystyrene(PSt-Br)4 was obtained from ATRP of styrene using pentaerythritol tetra(2-bromoisobutyrate) as an initiator,and the(PSt-Br)4 was efficiently converted to the azido-terminated polymers[(PSt-N3)4] through the bromine substitution reaction with sodium azide.Furthermore,the(PSt-N3)4 reacted with propargyl 2,2-bis[2-(bromomethyl)propionato]propionyrate via a click reaction,1,3-dipolar cycloaddition reaction,and the polymer[(PSt-Br2)4] containing eight end-bromine was obtained.The(PSt-Br2)4 could further serve as a macroinitiator for the ATRP of methyl methacrylate(MMA).Accordingly,the dendrimer-like star polymer,[(PMMA)2PSt]4 was successfully prepared.The structure of [(PMMA)2PSt]4 was characterized via IR,1H NMR,GPC and DSC.展开更多
Ethyl cellulose graft copolymers with block and hetero side chains, ethyl cellulose graft [polystyrene-b-poly- （ethylene glycol）] [EC-g-（PS-b-PEG）] and ethyl cellulose graft polystyrene and polyethylene glycol [EC...Ethyl cellulose graft copolymers with block and hetero side chains, ethyl cellulose graft [polystyrene-b-poly- （ethylene glycol）] [EC-g-（PS-b-PEG）] and ethyl cellulose graft polystyrene and polyethylene glycol [EC-g-（PS-PEG ）] were synthesized by atomic transfer radical polymerization （ATRP） and alkyne-azide ＂click＂ reactions and ＂one-pot＂ ATRP and ＂click＂ reactions, respectively. For the synthesis of EC-g-（PS-b-PEG）, the macroinitiator for ATRP was first synthesized via the esterification of hydroxyl groups of EC with 2-bromoisobutyryl bromide to re- sult ethyl cellulose 2-bromoisobutyryl ester （EC-Br）. The degree of substitution of bromide groups, which deter- mined the graft density, can be tailored by varying the feeding ratios of the hydroxyl groups to 2-bromoisobutyryl bromide. Then ATRP was carried out for preparing EC-g-PS-Br with well-defined length of PS chains. The EC-g-PS-Br copolymers were then converted to EC-g-PS-N3 and then reacted with end alkyne-functionalized PEG via click to result in EC-g-（PS-b-PEG）. The EC-g-（PS-PEG） copolymers were synthesized by converting bromide groups of EC-Br to azide groups （EC-Br-N3） and then by one-pot ATRP and ＂click＂ reactions. The resultant graft copolymers were characterized by FTIR and IH NMR. The results indicate the success of the synthetic procedure of the cellulose grail copolymers with block and hetero side chains.展开更多
基金supported by the"973"program of China(No.2009CB623402)Engineering Research Center of Ministry of Education of China(No.JD09011)
文摘Preparation of an amphiphilic graft copolymer having poly(phthalazinone ether sulfone ketone)(PPESK) as main chains was carried out by atom transfer radical polymerization(ATRP).The precursor,chloromethylated PPESK (CMPPESK),was prepared by using chioromethylether as chloromethylation agent.Then,poly(ethylene glycol) methyl ether methacrylate(PEGMA) was used as monomer to synthesize PPESK-g-P(PEGMA) by ATRP method under the catalysis of a cuprous chloride/2,2'-bipyridyl system.PPESK/PPESK-g-P(PEGMA) blend m...
文摘An efficient route to macrocyclic polymers via “click” cyclization was presented.The α-bromine and ω-alkyne PMMA were prepared using the standard ATRP technique,initiated with propargyl 2-bromoisobutyrate,Cu(Ⅰ)Br and N,N,N’,N″,N-pentamethyldiethylenetriamine(PMDETA).Azidation of the terminal bromine was followed in DMF with sodium azide,and α-azide,ω-alkyne PMMA precursor was obtained.Then the “click” cylcization of precursor between terminal azide and alkyne was carried out under the catalysis of CuBr/PMDETA,during the course of the reaction,a pseudo-high dilution technique was utilized to ensure the favored intramolecular cylcization.The nearly complete cylcization has been confirmed by a combination of IR,1H NMR and GPC analysis,and cyclo-PMMA with an Mn of 15000,PDI of 1.38 was obtained.
文摘A new approach to the synthesis of dendrimer-like star polymer,[(PMMA)2PSt]4,was presented via the combination of atom transfer radical polymerization(ATRP) and ckick chemistry.Firstly four-arm bromine-terminated polystyrene(PSt-Br)4 was obtained from ATRP of styrene using pentaerythritol tetra(2-bromoisobutyrate) as an initiator,and the(PSt-Br)4 was efficiently converted to the azido-terminated polymers[(PSt-N3)4] through the bromine substitution reaction with sodium azide.Furthermore,the(PSt-N3)4 reacted with propargyl 2,2-bis[2-(bromomethyl)propionato]propionyrate via a click reaction,1,3-dipolar cycloaddition reaction,and the polymer[(PSt-Br2)4] containing eight end-bromine was obtained.The(PSt-Br2)4 could further serve as a macroinitiator for the ATRP of methyl methacrylate(MMA).Accordingly,the dendrimer-like star polymer,[(PMMA)2PSt]4 was successfully prepared.The structure of [(PMMA)2PSt]4 was characterized via IR,1H NMR,GPC and DSC.
文摘Ethyl cellulose graft copolymers with block and hetero side chains, ethyl cellulose graft [polystyrene-b-poly- （ethylene glycol）] [EC-g-（PS-b-PEG）] and ethyl cellulose graft polystyrene and polyethylene glycol [EC-g-（PS-PEG ）] were synthesized by atomic transfer radical polymerization （ATRP） and alkyne-azide ＂click＂ reactions and ＂one-pot＂ ATRP and ＂click＂ reactions, respectively. For the synthesis of EC-g-（PS-b-PEG）, the macroinitiator for ATRP was first synthesized via the esterification of hydroxyl groups of EC with 2-bromoisobutyryl bromide to re- sult ethyl cellulose 2-bromoisobutyryl ester （EC-Br）. The degree of substitution of bromide groups, which deter- mined the graft density, can be tailored by varying the feeding ratios of the hydroxyl groups to 2-bromoisobutyryl bromide. Then ATRP was carried out for preparing EC-g-PS-Br with well-defined length of PS chains. The EC-g-PS-Br copolymers were then converted to EC-g-PS-N3 and then reacted with end alkyne-functionalized PEG via click to result in EC-g-（PS-b-PEG）. The EC-g-（PS-PEG） copolymers were synthesized by converting bromide groups of EC-Br to azide groups （EC-Br-N3） and then by one-pot ATRP and ＂click＂ reactions. The resultant graft copolymers were characterized by FTIR and IH NMR. The results indicate the success of the synthetic procedure of the cellulose grail copolymers with block and hetero side chains.
