Composite nanofiber membranes based on biodegradable poly(lactic acid)(PLA) and cellulose nanofibrils(CNF) were produced via electrospinning. The influence of CNF content on the morphology, thermal properties, and mec...Composite nanofiber membranes based on biodegradable poly(lactic acid)(PLA) and cellulose nanofibrils(CNF) were produced via electrospinning. The influence of CNF content on the morphology, thermal properties, and mechanical properties of PLA/CNF composite nanofiber membranes were characterized by field scanning electron microscopy(FE-SEM), differential scanning calorimetry(DSC), thermogravimetric analysis(TGA), and dynamic mechanical analysis(DMA), respectively. The results show that the PLA/CNF composite nanofibers with smooth, free-bead surface can be successfully fabricated with various CNF contents. The introduction of CNF is an effective approach to improve the crystalline ability, thermal stability and mechanical properties for PLA/CNF composite fibers. The Young's moduli and tensile strength of the PLA/CNF composite nanofiber reach 106.6 MPa and 2.7 MPa when the CNF content is 3%, respectively, which are one times higher and 1.5 times than those of pure PLA nanofiber. Additionally, the water contact angle of PLA/CNF composite nanofiber membranes decreases with the increase of the CNF loading, resulting in the enhancement of their hydrophilicity.展开更多
Graded porous scaffold can be applied to study the interactions between cells and scaffold with different pore sizes. Polydimethylsiloxane（PDMS） scaffold with an axial pore size grade was successfully manufactured v...Graded porous scaffold can be applied to study the interactions between cells and scaffold with different pore sizes. Polydimethylsiloxane（PDMS） scaffold with an axial pore size grade was successfully manufactured via vacuum-assisted resin transfer moulding（VARTM） and particle leaching technologies. The properties of graded PDMS scaffolds, including porosity, water absorption, interconnectivity, compression modulus, as well as compression strength were investigated. The results showed that the smaller the size of the NaCl particles is, the higher the porosity and water absorption of graded PDMS scaffolds would be. The graded PDMS scaffold fabricated had a compressive modulus and a compressive strength of 19.69±1.42 kPa and 4.76±0.22 kPa, respectively. Moreover, the graded chitosan（CS）-coated PDMS scaffolds were prepared by using dip-coating technique under low vacuum and their hydrophilicity was examined. It is found that the water contact angle（WCA） will decrease with an increase in the CS solution concentration and the coating time, which indicates that CS-coated PDMS scaffolds exhibit noticeable hydrophilicity compared with graded PDMS scaffold.展开更多
基金Funded by the Outstanding Young Scientific Research Personnel Training Plan in Colleges and Universities of Fujian Province(No.GY-Z160146)the Research Fund of Fujian University of Technology(Nos.GY-Z15091,GY-Z160121)+2 种基金the External Cooperative Projects of Fujian Province(No.2018I0001)the Young Teachers Education Research Project(No.JAT170377)Fujian Province Undergraduate Training Program for Innovation and Entrepreneurship(No.201810388048)
文摘Composite nanofiber membranes based on biodegradable poly(lactic acid)(PLA) and cellulose nanofibrils(CNF) were produced via electrospinning. The influence of CNF content on the morphology, thermal properties, and mechanical properties of PLA/CNF composite nanofiber membranes were characterized by field scanning electron microscopy(FE-SEM), differential scanning calorimetry(DSC), thermogravimetric analysis(TGA), and dynamic mechanical analysis(DMA), respectively. The results show that the PLA/CNF composite nanofibers with smooth, free-bead surface can be successfully fabricated with various CNF contents. The introduction of CNF is an effective approach to improve the crystalline ability, thermal stability and mechanical properties for PLA/CNF composite fibers. The Young's moduli and tensile strength of the PLA/CNF composite nanofiber reach 106.6 MPa and 2.7 MPa when the CNF content is 3%, respectively, which are one times higher and 1.5 times than those of pure PLA nanofiber. Additionally, the water contact angle of PLA/CNF composite nanofiber membranes decreases with the increase of the CNF loading, resulting in the enhancement of their hydrophilicity.
基金Supported by the Research Fund of Fujian University of Technology(Nos.GY-Z15091,GY-Z160121)the External Cooperative Projects of Fujian Province(No.2018I0001)+2 种基金the Young Teachers Education Research Project(No.JAT170377)the Outstanding Young Scientific Research Personnel Training Plan in Colleges and Universities of Fujian Province(No.GY-Z160146)Fujian Province Undergraduate Training Program for Innovation and Entrepreneurship(No.201710388055)
文摘Graded porous scaffold can be applied to study the interactions between cells and scaffold with different pore sizes. Polydimethylsiloxane（PDMS） scaffold with an axial pore size grade was successfully manufactured via vacuum-assisted resin transfer moulding（VARTM） and particle leaching technologies. The properties of graded PDMS scaffolds, including porosity, water absorption, interconnectivity, compression modulus, as well as compression strength were investigated. The results showed that the smaller the size of the NaCl particles is, the higher the porosity and water absorption of graded PDMS scaffolds would be. The graded PDMS scaffold fabricated had a compressive modulus and a compressive strength of 19.69±1.42 kPa and 4.76±0.22 kPa, respectively. Moreover, the graded chitosan（CS）-coated PDMS scaffolds were prepared by using dip-coating technique under low vacuum and their hydrophilicity was examined. It is found that the water contact angle（WCA） will decrease with an increase in the CS solution concentration and the coating time, which indicates that CS-coated PDMS scaffolds exhibit noticeable hydrophilicity compared with graded PDMS scaffold.
