Biodegradable poly(epsilon-caprolactone-co-p-dioxanone)(PCDO) random copolymers have been synthesized by ring-opening polymerization of epsilon-caprolactone(CL) and p-dioxanone(PDO) under microwave irradiation.The eff...Biodegradable poly(epsilon-caprolactone-co-p-dioxanone)(PCDO) random copolymers have been synthesized by ring-opening polymerization of epsilon-caprolactone(CL) and p-dioxanone(PDO) under microwave irradiation.The effects of irradiation time and different CL/PDO molar feed ratios on the microwave-assisted ring-opening polymerization(MROP) of PCDO have been discussed.The resultant products were characterized by ~1H NMR,GPC and DSC.It was found that the polymerization was completed within 20 min at 140℃.In th...展开更多
In order to expand the application of poly（p-dioxanone） or PPDO in biomedical area,a series of novel copolymers were synthesized successfully by one-step,melted copolymerization of p-dioxanone（PDO） and L-phenylala...In order to expand the application of poly（p-dioxanone） or PPDO in biomedical area,a series of novel copolymers were synthesized successfully by one-step,melted copolymerization of p-dioxanone（PDO） and L-phenylalanine N-carboxyanhydride（L-Phe-NCA） monomers.With the in-feed molar ratio of L-PheNCA /PDO equal to 1/20,the conversions of the two kinds of monomers were calculated from 1H NMR. The average molecular weight and polydispersity of the copolymer increase with the increasing reaction time and catalyst concentration.However,the conversions of the two kinds of monomers did not change with the reaction conditions.A three-step mechanism is presented and proved by high resolution 1H NMR and IR spectrums.展开更多
A series of novel poly（urethane-urea）（PUU） was synthesized from poly（lactide-co-p-dioxanone） macrodiol（HO-P（LA-co-PDO）-OH）, hexamethylene diisocyanate（HDI） and butanediamine（BDA）.The obtained PUU,which i...A series of novel poly（urethane-urea）（PUU） was synthesized from poly（lactide-co-p-dioxanone） macrodiol（HO-P（LA-co-PDO）-OH）, hexamethylene diisocyanate（HDI） and butanediamine（BDA）.The obtained PUU,which is recorded as P（LA-co-PDO）-PUU here,may demonstrate enhanced phase separation and thus improved shape memory property.FTIR was employed to characterize the copolymers,and the effects of NCO/OH molar ratios on Tg of PUU was investigated by means of differential scanning calorimetry （DSC）.The results revealed the successful synthesis of P（LA-co-PDO）-PUU.In addition,the Tg of P（LA-co-PDO）-PUU increased from 37.9℃to 44.2℃with the increase NCO/OH ratios from 1.1 to 1.2.The P（LA-co-PDO）-PUU with Tg close to body temperature will have potential applications as shape memory polymers in biomedical fields,especially in minimally invasive surgery.展开更多
Integrating poly（lactic acid） （PLA）, glycolic acid （GA） and ethylene glycol （EG） will hopefully result in a novel copolymer that combines such advantages as fastened and controllable release rate and improved ...Integrating poly（lactic acid） （PLA）, glycolic acid （GA） and ethylene glycol （EG） will hopefully result in a novel copolymer that combines such advantages as fastened and controllable release rate and improved flexibility together with good biocompatibility. In this study, p-dioxanone （PDO） was employed to copolymerize with DL-lactide （LA） via ring-opening melt polymerization using Sn（Oct）2 as an initiator and ethylene glycol as a co-initiator. The obtained degradable macrodiols （HO-P（LA-co-PDO）-OH） were just such a copolymer consisting of PLA, GA and EG. 1HNMR was employed to characterize the copolymers, and the effect of PDO/LA molar ratios in the feedstock on the molecular weights of HO-P（LA-co-PDO）-OH was investigated by means of endhydroxyl analysis, 1H NMR or GPC-MALLs. The results confirmed the successful synthesis of HO-P（LA-co-PDO）-OH and revealed that one end-hydroxyl of the micarodiols was donated by LA or PDO and the other one by the co-initiator EG. In addition, the molecular weights of HO-P（LA-co-PDO）-OH increased with decreasing PDO/LA ratios.展开更多
Novel amphiphilic triblock copolymer poly（p-dioxanone-co-5-benzyloxytrimethylene carbonate）-block-poly（ethylene glycol）-block-poly（p-dioxanone-co-5-benzyloxytrimethylene carbonate） （p（PDO-co-BTMC）-b-PEG-b-p（...Novel amphiphilic triblock copolymer poly（p-dioxanone-co-5-benzyloxytrimethylene carbonate）-block-poly（ethylene glycol）-block-poly（p-dioxanone-co-5-benzyloxytrimethylene carbonate） （p（PDO-co-BTMC）-b-PEG-b-p（PDO-co-BTMC）） was successfully synthesized using immobilized porcine pancreas lipase on porous silica particles （IPPL） as the catalyst for the fLrSt time. 1H NMR, 13C NMR and GPC analysis were used to confirm the structures of resulting copolymers. The molecular weight （Mn） of the copolymer with feed ratio of 69：20：11 （BTMC： PDO： PEG ） was 31300 g/mol and the polydispersity was 1.85, while the Mn decreased to 25000 g/mol and polydispersity of 1.93 with the feed ratio of 50：40：10.展开更多
By using the corresponding L-amino acid sodium as initiator,ε-caprolactone-depsipeptides CL-Ala and CL-Leu were prepared by the reactions ofε-caprolactone(CL)with L-alanine and L-leucine,respec-tively,and p-dioxanon...By using the corresponding L-amino acid sodium as initiator,ε-caprolactone-depsipeptides CL-Ala and CL-Leu were prepared by the reactions ofε-caprolactone(CL)with L-alanine and L-leucine,respec-tively,and p-dioxanone-depsipeptide(PDO-Leu)was prepared by the reaction of p-dioxanone(PDO)with L-leucine.Two poly(ε-caprolactone)oligomers(PCL-Ala and PCL-Leu)of different molecular weights with depsipeptide unit were synthesized by controlling the feed ratio of L-amino acid sodium and CL.The presence of the depsipeptide structure in these obtained products was confirmed by 1H NMR spectra and the molecular weight of the poly(ε-caprolactone)oligomers was measured by gel permeation chromatography(GPC).These products con-tain a hydroxyl group and a carboxyl group in one molecule,which means they could act as bifunctional monomers for further polymerization to prepare high molecular weight polymers.By this way,the depsipeptide unit could be introduced into the polymers and the biodegradation rates of the novel polymers could be well controlled in vivo by the tailored molecular structures.展开更多
文摘Biodegradable poly(epsilon-caprolactone-co-p-dioxanone)(PCDO) random copolymers have been synthesized by ring-opening polymerization of epsilon-caprolactone(CL) and p-dioxanone(PDO) under microwave irradiation.The effects of irradiation time and different CL/PDO molar feed ratios on the microwave-assisted ring-opening polymerization(MROP) of PCDO have been discussed.The resultant products were characterized by ~1H NMR,GPC and DSC.It was found that the polymerization was completed within 20 min at 140℃.In th...
基金supported financially by the "Western Light" joint researcher program of Chinese Academy of Science
文摘In order to expand the application of poly（p-dioxanone） or PPDO in biomedical area,a series of novel copolymers were synthesized successfully by one-step,melted copolymerization of p-dioxanone（PDO） and L-phenylalanine N-carboxyanhydride（L-Phe-NCA） monomers.With the in-feed molar ratio of L-PheNCA /PDO equal to 1/20,the conversions of the two kinds of monomers were calculated from 1H NMR. The average molecular weight and polydispersity of the copolymer increase with the increasing reaction time and catalyst concentration.However,the conversions of the two kinds of monomers did not change with the reaction conditions.A three-step mechanism is presented and proved by high resolution 1H NMR and IR spectrums.
基金supported by the National Key Technologies R&D Program of China(No.2006BA103B04)the Natural Key Scientific and Technological Project of Chongqing(No.CSTC 2008AB0027)
文摘A series of novel poly（urethane-urea）（PUU） was synthesized from poly（lactide-co-p-dioxanone） macrodiol（HO-P（LA-co-PDO）-OH）, hexamethylene diisocyanate（HDI） and butanediamine（BDA）.The obtained PUU,which is recorded as P（LA-co-PDO）-PUU here,may demonstrate enhanced phase separation and thus improved shape memory property.FTIR was employed to characterize the copolymers,and the effects of NCO/OH molar ratios on Tg of PUU was investigated by means of differential scanning calorimetry （DSC）.The results revealed the successful synthesis of P（LA-co-PDO）-PUU.In addition,the Tg of P（LA-co-PDO）-PUU increased from 37.9℃to 44.2℃with the increase NCO/OH ratios from 1.1 to 1.2.The P（LA-co-PDO）-PUU with Tg close to body temperature will have potential applications as shape memory polymers in biomedical fields,especially in minimally invasive surgery.
基金supported by the National Key Technologies R&D Program of China(No.2006BA103B04)the Natural Key Scientific and Technological Project of Chongqing(No.CSTC 2008AB0027)
文摘Integrating poly（lactic acid） （PLA）, glycolic acid （GA） and ethylene glycol （EG） will hopefully result in a novel copolymer that combines such advantages as fastened and controllable release rate and improved flexibility together with good biocompatibility. In this study, p-dioxanone （PDO） was employed to copolymerize with DL-lactide （LA） via ring-opening melt polymerization using Sn（Oct）2 as an initiator and ethylene glycol as a co-initiator. The obtained degradable macrodiols （HO-P（LA-co-PDO）-OH） were just such a copolymer consisting of PLA, GA and EG. 1HNMR was employed to characterize the copolymers, and the effect of PDO/LA molar ratios in the feedstock on the molecular weights of HO-P（LA-co-PDO）-OH was investigated by means of endhydroxyl analysis, 1H NMR or GPC-MALLs. The results confirmed the successful synthesis of HO-P（LA-co-PDO）-OH and revealed that one end-hydroxyl of the micarodiols was donated by LA or PDO and the other one by the co-initiator EG. In addition, the molecular weights of HO-P（LA-co-PDO）-OH increased with decreasing PDO/LA ratios.
基金the financial support of the National Natural Science Foundation of China(No.20104005).
文摘Novel amphiphilic triblock copolymer poly（p-dioxanone-co-5-benzyloxytrimethylene carbonate）-block-poly（ethylene glycol）-block-poly（p-dioxanone-co-5-benzyloxytrimethylene carbonate） （p（PDO-co-BTMC）-b-PEG-b-p（PDO-co-BTMC）） was successfully synthesized using immobilized porcine pancreas lipase on porous silica particles （IPPL） as the catalyst for the fLrSt time. 1H NMR, 13C NMR and GPC analysis were used to confirm the structures of resulting copolymers. The molecular weight （Mn） of the copolymer with feed ratio of 69：20：11 （BTMC： PDO： PEG ） was 31300 g/mol and the polydispersity was 1.85, while the Mn decreased to 25000 g/mol and polydispersity of 1.93 with the feed ratio of 50：40：10.
基金financially supported by Program for the New Century Excellent Talents in University“NCET”,Ministry of Education of China,and by the International Cooperation from Ministry of Science and Technology of China(Grant No.2008DFA51170)sponsored by the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education of China.
文摘By using the corresponding L-amino acid sodium as initiator,ε-caprolactone-depsipeptides CL-Ala and CL-Leu were prepared by the reactions ofε-caprolactone(CL)with L-alanine and L-leucine,respec-tively,and p-dioxanone-depsipeptide(PDO-Leu)was prepared by the reaction of p-dioxanone(PDO)with L-leucine.Two poly(ε-caprolactone)oligomers(PCL-Ala and PCL-Leu)of different molecular weights with depsipeptide unit were synthesized by controlling the feed ratio of L-amino acid sodium and CL.The presence of the depsipeptide structure in these obtained products was confirmed by 1H NMR spectra and the molecular weight of the poly(ε-caprolactone)oligomers was measured by gel permeation chromatography(GPC).These products con-tain a hydroxyl group and a carboxyl group in one molecule,which means they could act as bifunctional monomers for further polymerization to prepare high molecular weight polymers.By this way,the depsipeptide unit could be introduced into the polymers and the biodegradation rates of the novel polymers could be well controlled in vivo by the tailored molecular structures.
