The effects of glycerol and sorbitol as two plasticizers on mechanical properties, water vapor permeability, thermal properties, color and capability of heat sealing of gelatin films (of phytophagous fish, bovine gela...The effects of glycerol and sorbitol as two plasticizers on mechanical properties, water vapor permeability, thermal properties, color and capability of heat sealing of gelatin films (of phytophagous fish, bovine gelatin with high gel-forming ability, and bovine gelatin with low gel-forming ability) containing clay nanoparticles were studied in this research. For this purpose, 6 × 2 × 3 factorial experiments using the completely randomized design and comparison of the means at 95% confidence level (α = 0.05) were performed. Higher concentrations of plasticizers increased percentage elongation to the breaking point. When glycerol concentration was raised to over 20%, flexibility of the layers improved but their water vapor permeability increased. The minimum passage of water vapor was that of fish-skin gelatin films containing clay nanoparticles and 30% sorbitol, and the maximum that of bovine gelatin films with high gel-forming ability which contained nanoparticles but no plasticizers (p 0.05). All samples had heat sealing capability, and fish-skin gelatin films containing clay nanoparticles had better heat sealing capability compared with the other samples so that fish-skin gelatin films containing clay nanoparticles with 25% glycerol and 5% sorbitol had the highest flexibility and tensile strength, and remained attached to where they were heat sealed. Electron microscope images showed that films without plasticizers had uniform surfaces, but that samples containing glycerol at concentrations of over 0.20 g/g gelatin exhibited cavities between gelatin chains and that water vapor permeability in gelatin films containing clay nanoparticles.展开更多
This paper deals with the mechanical properties and permeability of mortar modified with Metakaolin. Comparisons were made to normal mortar without metakaolin in order to determine its influence of addition and replac...This paper deals with the mechanical properties and permeability of mortar modified with Metakaolin. Comparisons were made to normal mortar without metakaolin in order to determine its influence of addition and replacement percentage. Cement was replaced on a mass basis of 5%～20% for metakaolin. The permeability determined by the electric flux and water absorption was investigated as well as mechanical properties. Technique of Scanning electron microscopy (SEM) was employed to characterize the microstructure of the new mortar system. The experimental results obtained reveal that Metakaolin contributed to lower the water absorption rate and the electric flux and yield a good mechanical property. Moreover,there exists an optimal displacement percentage of metakaolin,15%,in the mortar system. SEM pictures illustrate that Metakaolin makes mortar more compacted. Evidence can be given that Metakaolin can be applied to protect the steel reinforcement of concrete from corrosion.展开更多
文摘The effects of glycerol and sorbitol as two plasticizers on mechanical properties, water vapor permeability, thermal properties, color and capability of heat sealing of gelatin films (of phytophagous fish, bovine gelatin with high gel-forming ability, and bovine gelatin with low gel-forming ability) containing clay nanoparticles were studied in this research. For this purpose, 6 × 2 × 3 factorial experiments using the completely randomized design and comparison of the means at 95% confidence level (α = 0.05) were performed. Higher concentrations of plasticizers increased percentage elongation to the breaking point. When glycerol concentration was raised to over 20%, flexibility of the layers improved but their water vapor permeability increased. The minimum passage of water vapor was that of fish-skin gelatin films containing clay nanoparticles and 30% sorbitol, and the maximum that of bovine gelatin films with high gel-forming ability which contained nanoparticles but no plasticizers (p 0.05). All samples had heat sealing capability, and fish-skin gelatin films containing clay nanoparticles had better heat sealing capability compared with the other samples so that fish-skin gelatin films containing clay nanoparticles with 25% glycerol and 5% sorbitol had the highest flexibility and tensile strength, and remained attached to where they were heat sealed. Electron microscope images showed that films without plasticizers had uniform surfaces, but that samples containing glycerol at concentrations of over 0.20 g/g gelatin exhibited cavities between gelatin chains and that water vapor permeability in gelatin films containing clay nanoparticles.
基金supported by"the Fundamental Research Funds for the Central Universities"(No.2010-Ⅳ-057)
文摘This paper deals with the mechanical properties and permeability of mortar modified with Metakaolin. Comparisons were made to normal mortar without metakaolin in order to determine its influence of addition and replacement percentage. Cement was replaced on a mass basis of 5%～20% for metakaolin. The permeability determined by the electric flux and water absorption was investigated as well as mechanical properties. Technique of Scanning electron microscopy (SEM) was employed to characterize the microstructure of the new mortar system. The experimental results obtained reveal that Metakaolin contributed to lower the water absorption rate and the electric flux and yield a good mechanical property. Moreover,there exists an optimal displacement percentage of metakaolin,15%,in the mortar system. SEM pictures illustrate that Metakaolin makes mortar more compacted. Evidence can be given that Metakaolin can be applied to protect the steel reinforcement of concrete from corrosion.
