After removal of the caries or diseased teeth,the alveolar ridge will undergo absorption and atrophy.When the amount of alveolar bone is insufficient,it will cause an inability to perform effective dental implant rest...After removal of the caries or diseased teeth,the alveolar ridge will undergo absorption and atrophy.When the amount of alveolar bone is insufficient,it will cause an inability to perform effective dental implant restoration.In order to control the absorption and promote the repair and regeneration of alveolar ridge,a method of implanting guided bone regeneration(GBR)membranes at the extraction site is often used.In this study,silk fibroin(SF)and poly-L-lactide lactone(PLCL)were used to prepare bilayered guided bone regeneration membranes,and its morphology,hydrophilicity,surface roughness and mechanical properties were studied.At the same time,the drug release behaviors and cell compatibility of the bilayered membranes were studied.The results showed that SF/PLCL bi-layered membranes had good mechanical properties and surface hydrophilicity,and the drug-loaded bi-layered membranes had good cell compatibility.The bilayered membranes fabricated in this study are of potential for applying in the oral health field to promote bone regeneration.展开更多
Poly（N-trityl serine lactone）（PTSL） and mPEG-block-poly（N-trityl serine lactone）（mPEG-b-PTSL, PEG= polyethylene glycol） were synthesized via the ring-opening polymerization of N-trityl serine lactone（TSL） wi...Poly（N-trityl serine lactone）（PTSL） and mPEG-block-poly（N-trityl serine lactone）（mPEG-b-PTSL, PEG= polyethylene glycol） were synthesized via the ring-opening polymerization of N-trityl serine lactone（TSL） with diethyl zinc（ZnEt2） as catalyst. The structures of these polymers were confirmed with hydrogen nuclear magnetic resonance（IH NMR） spectroscopy, carbon nuclear magnetic resonance（13C NMR） spectroscopy and infrared（IR） spectrometer. The thermal decomposition temperature and glass transition temperature of PTSL were 241 and 161 ℃, respectively. A series of mPEG-b-PTSL with different molecular weights（Mn＇s from 7000 to 32000） was obtained by tuning the TSL/mPEG feed ratio. After the removal of the trityl groups, mPEG-block-poly（serine lactone）（mPEG- b-PSL） was obtained as a new kind of cationic block copolymer. Low cytotoxicity of these polymers to L929 cells was confirmed via 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay.展开更多
Copolymerization is a commonly employed method for optimizing the properties of polymer materials.Incorporating ether segments into polyesters main chain to obtain polyether-polyester copolymers is an effective strate...Copolymerization is a commonly employed method for optimizing the properties of polymer materials.Incorporating ether segments into polyesters main chain to obtain polyether-polyester copolymers is an effective strategy to realize the integration of multiple properties of polyester and polyether,and to develop more high-performance,multi-purpose polymer materials.Herein,the synthesis of poly(ether-ester)s is accessible by employing the biphenyl-linked heterodinuclear salen Cr-AI complex in the presence of PPNCI for the copolymerization of epoxides and£-caprolactone(CL).Monitoring the copolymerization process reveals that catalyst 1 exhibited good performance for the copolymerization of epoxides and CL,affording copolymers with a gradient sequence structure.The dynamic thermomechanical analysis(DMA)study indicates the obtained poly(ether-ester)s possess enhanced flexibility compared with the block copolymers or blend of PPO and PCL homopolymers with the same ratio.This study provides a theoretical basis for the preparation of high-performance polymer materials.展开更多
基金Natural Science Foundation for Key Program of the Jiangsu Higher Education Institutions,China(No.19KJA610004)Natural Science Foundation of Jiangsu Province,China(No.BK20161254)+1 种基金China Postdoctoral Science Foundation(No.2019M651947)Mandatory Projects of Nantong Municipal Science and Technology Plan,China(No.JC2018004)
文摘After removal of the caries or diseased teeth,the alveolar ridge will undergo absorption and atrophy.When the amount of alveolar bone is insufficient,it will cause an inability to perform effective dental implant restoration.In order to control the absorption and promote the repair and regeneration of alveolar ridge,a method of implanting guided bone regeneration(GBR)membranes at the extraction site is often used.In this study,silk fibroin(SF)and poly-L-lactide lactone(PLCL)were used to prepare bilayered guided bone regeneration membranes,and its morphology,hydrophilicity,surface roughness and mechanical properties were studied.At the same time,the drug release behaviors and cell compatibility of the bilayered membranes were studied.The results showed that SF/PLCL bi-layered membranes had good mechanical properties and surface hydrophilicity,and the drug-loaded bi-layered membranes had good cell compatibility.The bilayered membranes fabricated in this study are of potential for applying in the oral health field to promote bone regeneration.
基金Supported by the National Natural Science Foundation of China（No s.51021003, 21174143）.
文摘Poly（N-trityl serine lactone）（PTSL） and mPEG-block-poly（N-trityl serine lactone）（mPEG-b-PTSL, PEG= polyethylene glycol） were synthesized via the ring-opening polymerization of N-trityl serine lactone（TSL） with diethyl zinc（ZnEt2） as catalyst. The structures of these polymers were confirmed with hydrogen nuclear magnetic resonance（IH NMR） spectroscopy, carbon nuclear magnetic resonance（13C NMR） spectroscopy and infrared（IR） spectrometer. The thermal decomposition temperature and glass transition temperature of PTSL were 241 and 161 ℃, respectively. A series of mPEG-b-PTSL with different molecular weights（Mn＇s from 7000 to 32000） was obtained by tuning the TSL/mPEG feed ratio. After the removal of the trityl groups, mPEG-block-poly（serine lactone）（mPEG- b-PSL） was obtained as a new kind of cationic block copolymer. Low cytotoxicity of these polymers to L929 cells was confirmed via 3-（4,5-dimethylthiazol-2-yl）-2,5-diphenyltetrazolium bromide（MTT） assay.
基金the National Natural Science Foundation of China(Nos.21722402 and 21674015).
文摘Copolymerization is a commonly employed method for optimizing the properties of polymer materials.Incorporating ether segments into polyesters main chain to obtain polyether-polyester copolymers is an effective strategy to realize the integration of multiple properties of polyester and polyether,and to develop more high-performance,multi-purpose polymer materials.Herein,the synthesis of poly(ether-ester)s is accessible by employing the biphenyl-linked heterodinuclear salen Cr-AI complex in the presence of PPNCI for the copolymerization of epoxides and£-caprolactone(CL).Monitoring the copolymerization process reveals that catalyst 1 exhibited good performance for the copolymerization of epoxides and CL,affording copolymers with a gradient sequence structure.The dynamic thermomechanical analysis(DMA)study indicates the obtained poly(ether-ester)s possess enhanced flexibility compared with the block copolymers or blend of PPO and PCL homopolymers with the same ratio.This study provides a theoretical basis for the preparation of high-performance polymer materials.
