A series of degradable polyesters was synthesized via melt polymerization of 3,6-dioxaoctane-1,8-dioic acid and five different diols,catalyzed by antimony trioxide(Sb_(2)O_(3)).The polymers were characterized by FT-IR...A series of degradable polyesters was synthesized via melt polymerization of 3,6-dioxaoctane-1,8-dioic acid and five different diols,catalyzed by antimony trioxide(Sb_(2)O_(3)).The polymers were characterized by FT-IR and ^(1)H NMR spectroscopy,gel permeation chromatography(GPC)and differential scanning calorimetry(DSC)analysis.The polydispersity index(PDI=M_(w)/M_(n))of the polyesters ranged from 1.55 to 1.99,the weight-average molecular weight(M_(w))from 1.8×10^(4) to 3.2×10^(4) Da,the melting point from 63 to 123℃,and the highest decomposition temperature observed was 363℃.The influence of the structure of the polymer chain on hydrolytic degradability was investigated with tests performed at three different values of pH.The findings obtained provide useful insight for the molecular design and the synthesis of degradable polyesters.展开更多
A kind of full biodegradable film material is discussed in this article. The film material is composed of starch, PVA, degradable polyesters(PHB, PHB V, PCL) with built plasticizer, a cross linking reinforcing agen...A kind of full biodegradable film material is discussed in this article. The film material is composed of starch, PVA, degradable polyesters(PHB, PHB V, PCL) with built plasticizer, a cross linking reinforcing agent and a wet strengthening agent. It contains a high percentage of starch, costs cheap and is excellent in weather fastness, temperature resistance and waterproof and it could be completely biodegraded. The present paper deals mainly with a new technical route using a new type of electromagnetic dynamic blow molding extruder and some effects on mechanical properties of the system.展开更多
Three kinds of Keggin-type titanium-based polyoxometalate-ionic liquid catalysts were prepared,and the chemical structure,crystal structure and thermal stability of the three catalysts were analyzed and tested by infr...Three kinds of Keggin-type titanium-based polyoxometalate-ionic liquid catalysts were prepared,and the chemical structure,crystal structure and thermal stability of the three catalysts were analyzed and tested by infrared spectrometer,ultraviolet-visible spectrometer,X-ray diffractometer,and thermogravimetric analyzer,respectively.Afterwards,their performance in catalyzing the coupling reaction of ethylene carbonate(EC)and dimethyl succinate(DMSu)to synthesize polyethylene succinate(PES)was studied,and the effects of different metals on the catalytic performance and the mechanism of action were discussed.The optimal process parameters for the coupling reaction were explored.Finally,the chemical structure of PES was characterized by infrared spectrometer.The results show that under the same process parameters,the polyoxometalate-ionic liquid catalyst Bmim_(5)[Ti(H_(2)O)TiMo_(11)O_(39)]had the best catalytic effect.Under the optimal process parameters,Bmim_(5)[Ti(H_(2)O)TiMo_(11)O_(39)]had obvious inhibitory effect on side reactions,and the yield and selectivity of PES prepolymer were up to 72.23%and 88.64%.展开更多
In this study,a novel porous 3D composite scaffold based on the biodegradable Poly(ε-caprolactone)(PCL),Polylactide Acid(PLA)and Calcium Citrate(CC)was developed via polymer blends and thermal-induced phase separatio...In this study,a novel porous 3D composite scaffold based on the biodegradable Poly(ε-caprolactone)(PCL),Polylactide Acid(PLA)and Calcium Citrate(CC)was developed via polymer blends and thermal-induced phase separation.The chemical structure,crystalline structure and micromorphology as well as mechanical strength of the scaffolds were characterized by Fourier Transform Infrared Spectroscopy(FTIR),X-ray Diffraction(XRD),Scanning Electron Microscope(SEM)and tensile tests.The results show that the obtained composite scaffold present a suitable bone-like porous structure and sufficient mechanical strength.Furthermore,the release of calcium ions in Simulated Body Fluid(SBF)indicates that the composite material can provide a stable calcium-ion environment and maintain a constant pH value during the soaking process.The cell proliferation results from CCK-8 and light microscopy show that MG63 cells exhibit excellent adhesion and proliferation on the stent.At the same time,animal implantation histology confirms that the composite scaffolds have good biocompatibility in vivo.The scaffold material has greatly potential application value in the field of bone tissue engineering.展开更多
基金Funded by the Program(BG20190227001)of High-end Foreign Experts of the State Administration of Foreign Experts Affairs(SAFEA)the Coal Conversion and New Carbon Materials Hubei Key Laboratory in Wuhan University of Science and Technology(WKDM201909)。
文摘A series of degradable polyesters was synthesized via melt polymerization of 3,6-dioxaoctane-1,8-dioic acid and five different diols,catalyzed by antimony trioxide(Sb_(2)O_(3)).The polymers were characterized by FT-IR and ^(1)H NMR spectroscopy,gel permeation chromatography(GPC)and differential scanning calorimetry(DSC)analysis.The polydispersity index(PDI=M_(w)/M_(n))of the polyesters ranged from 1.55 to 1.99,the weight-average molecular weight(M_(w))from 1.8×10^(4) to 3.2×10^(4) Da,the melting point from 63 to 123℃,and the highest decomposition temperature observed was 363℃.The influence of the structure of the polymer chain on hydrolytic degradability was investigated with tests performed at three different values of pH.The findings obtained provide useful insight for the molecular design and the synthesis of degradable polyesters.
文摘A kind of full biodegradable film material is discussed in this article. The film material is composed of starch, PVA, degradable polyesters(PHB, PHB V, PCL) with built plasticizer, a cross linking reinforcing agent and a wet strengthening agent. It contains a high percentage of starch, costs cheap and is excellent in weather fastness, temperature resistance and waterproof and it could be completely biodegraded. The present paper deals mainly with a new technical route using a new type of electromagnetic dynamic blow molding extruder and some effects on mechanical properties of the system.
基金Supported by the Key Project of Education Department of Liaoning Province(LZGD2020005)。
文摘Three kinds of Keggin-type titanium-based polyoxometalate-ionic liquid catalysts were prepared,and the chemical structure,crystal structure and thermal stability of the three catalysts were analyzed and tested by infrared spectrometer,ultraviolet-visible spectrometer,X-ray diffractometer,and thermogravimetric analyzer,respectively.Afterwards,their performance in catalyzing the coupling reaction of ethylene carbonate(EC)and dimethyl succinate(DMSu)to synthesize polyethylene succinate(PES)was studied,and the effects of different metals on the catalytic performance and the mechanism of action were discussed.The optimal process parameters for the coupling reaction were explored.Finally,the chemical structure of PES was characterized by infrared spectrometer.The results show that under the same process parameters,the polyoxometalate-ionic liquid catalyst Bmim_(5)[Ti(H_(2)O)TiMo_(11)O_(39)]had the best catalytic effect.Under the optimal process parameters,Bmim_(5)[Ti(H_(2)O)TiMo_(11)O_(39)]had obvious inhibitory effect on side reactions,and the yield and selectivity of PES prepolymer were up to 72.23%and 88.64%.
基金jointly supported by the National Natural Science Foundation of China(NO.41673109)Sichuan Science and Technology Program(2021YFH0098)Key Project of Sichuan Vanadium and Titanium Industry Development Research Center(2018VTCYZ-01).
文摘In this study,a novel porous 3D composite scaffold based on the biodegradable Poly(ε-caprolactone)(PCL),Polylactide Acid(PLA)and Calcium Citrate(CC)was developed via polymer blends and thermal-induced phase separation.The chemical structure,crystalline structure and micromorphology as well as mechanical strength of the scaffolds were characterized by Fourier Transform Infrared Spectroscopy(FTIR),X-ray Diffraction(XRD),Scanning Electron Microscope(SEM)and tensile tests.The results show that the obtained composite scaffold present a suitable bone-like porous structure and sufficient mechanical strength.Furthermore,the release of calcium ions in Simulated Body Fluid(SBF)indicates that the composite material can provide a stable calcium-ion environment and maintain a constant pH value during the soaking process.The cell proliferation results from CCK-8 and light microscopy show that MG63 cells exhibit excellent adhesion and proliferation on the stent.At the same time,animal implantation histology confirms that the composite scaffolds have good biocompatibility in vivo.The scaffold material has greatly potential application value in the field of bone tissue engineering.
