Three types of organic compounds--two carboxylic acids and an anhydride, were used as additives for polyketone （PK）. The effect of the additive structure and their feed ratios on the melting temperature, crystalliza...Three types of organic compounds--two carboxylic acids and an anhydride, were used as additives for polyketone （PK）. The effect of the additive structure and their feed ratios on the melting temperature, crystallization temperature, and crystallization rate of PK were studied. We found that the crystallization temperature could be reduced significantly by introducing a small quantity of organic additive, in particular, an anhydride. On addition of 1 phr of anhydride, the crystallization temperature was reduced by 10.7 ℃. Therefore, the non-isothermal crystallization kinetics of aliphatic PKJanhydride blends with various feed ratios was investigated using DSC. The results were analyzed by various theoretical models, such as Avrami, Ozawa and combined Avrami-Ozawa models.展开更多
Among many biomaterials,gelatin methacrylate(GelMA),a photocurable protein,has been widely used in 3D bioprinting process owing to its excellent cellular responses,biocompatibility and biodegradability.However,GelMA s...Among many biomaterials,gelatin methacrylate(GelMA),a photocurable protein,has been widely used in 3D bioprinting process owing to its excellent cellular responses,biocompatibility and biodegradability.However,GelMA still shows a low processability due to the severe temperature dependence of viscosity.To overcome this obstacle,we propose a two-stage temperature control system to effectively control the viscosity of GelMA.To optimize the process conditions,we evaluated the temperature of the cooling system(jacket and stage).Using the established system,three GelMA scaffolds were fabricated in which different concentrations(0,3 and 10 wt%)of silanated silica particles were embedded.To evaluate the performances of the prepared scaffolds suitable for hard tissue regeneration,we analyzed the physical(viscoelasticity,surface roughness,compressive modulus and wettability)and biological(human mesenchymal stem cells growth,western blotting and osteogenic differentiation)properties.Consequently,the composite scaffold with greater silica contents(10 wt%)showed enhanced physical and biological performances including mechanical strength,cell initial attachment,cell proliferation and osteogenic differentiation compared with those of the controls.Our results indicate that the GelMA/silanated silica composite scaffold can be potentially used for hard tissue regeneration.展开更多
文摘Three types of organic compounds--two carboxylic acids and an anhydride, were used as additives for polyketone （PK）. The effect of the additive structure and their feed ratios on the melting temperature, crystallization temperature, and crystallization rate of PK were studied. We found that the crystallization temperature could be reduced significantly by introducing a small quantity of organic additive, in particular, an anhydride. On addition of 1 phr of anhydride, the crystallization temperature was reduced by 10.7 ℃. Therefore, the non-isothermal crystallization kinetics of aliphatic PKJanhydride blends with various feed ratios was investigated using DSC. The results were analyzed by various theoretical models, such as Avrami, Ozawa and combined Avrami-Ozawa models.
基金This research was supported by Priority Research Centers Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2018R1D1A1B07049434)supported by the Technology development Program(S2839376)funded by the Ministry of SMEs and Startups(MSS,Korea)also was supported by Priority Research Centers Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF-2020R1F1A1056503).
文摘Among many biomaterials,gelatin methacrylate(GelMA),a photocurable protein,has been widely used in 3D bioprinting process owing to its excellent cellular responses,biocompatibility and biodegradability.However,GelMA still shows a low processability due to the severe temperature dependence of viscosity.To overcome this obstacle,we propose a two-stage temperature control system to effectively control the viscosity of GelMA.To optimize the process conditions,we evaluated the temperature of the cooling system(jacket and stage).Using the established system,three GelMA scaffolds were fabricated in which different concentrations(0,3 and 10 wt%)of silanated silica particles were embedded.To evaluate the performances of the prepared scaffolds suitable for hard tissue regeneration,we analyzed the physical(viscoelasticity,surface roughness,compressive modulus and wettability)and biological(human mesenchymal stem cells growth,western blotting and osteogenic differentiation)properties.Consequently,the composite scaffold with greater silica contents(10 wt%)showed enhanced physical and biological performances including mechanical strength,cell initial attachment,cell proliferation and osteogenic differentiation compared with those of the controls.Our results indicate that the GelMA/silanated silica composite scaffold can be potentially used for hard tissue regeneration.
