Fibrous brucite,a kind of brucite with unique structure and physical properties,was modified with stearic acid as a surface modifier.In order to investigate the mechanism of surface modification,the fixation of steari...Fibrous brucite,a kind of brucite with unique structure and physical properties,was modified with stearic acid as a surface modifier.In order to investigate the mechanism of surface modification,the fixation of stearic acid on fibrous brucite and the induced changes in surface properties were studied by using X-ray diffraction(XRD),scanning electron microscopy(SEM),infrared spectroscopy(IR),Raman spectroscopy and thermo-gravimetric analysis(TGA).XRD analysis indicates that the modification of fibrous brucite with stearic acid does not cause any changes in the structure of fibrous brucite mineral.Spectroscopy and thermal analysis show that the surfactant molecules are not only directly adsorbed on the surface of the mineral,but also chemisorbed on mineral surface by forming chemical bonds between the modifier and magnesium hydroxide.展开更多
A calcium sulfate whisker (CSW) coated with glutaraldehyde crosslinked chitosan (GACS) was prepared to reinforce polyvinyl chloride (PVC) in this study. The results show that the optimum concentration of both ch...A calcium sulfate whisker (CSW) coated with glutaraldehyde crosslinked chitosan (GACS) was prepared to reinforce polyvinyl chloride (PVC) in this study. The results show that the optimum concentration of both chitosan (CS) and glutaraldehyde (GA) is 0.05 wt%. The tensile strength, impact strength, flexural modulus and vicat softening temperature of the PVC composite with 12 wt% of modified CSW are in- creased by 1 Z5%, 40.4%, 0.8% and 3.8% compared with those of the PVC composite with 12 wt~ of unmodified CSW, and by 2.9%, 42.4%, 2Z1% and 6.8% compared with those of pure PVC, respectively. The dynamic mechanical analysis results indicate that the modified CSW/PVC composite exhibits much higher storage modulus and glass transition temperature than those of unmodified CSW/PVC composite and pure PVC. In addition, the modified CSW/PVC composite also demonstrates good thermal properties with a high rapidest decomposition temperature (Trvd) and char residue. The scanning electron microscopy images of tensile-fractured surfaces show that the modified CSW has a strong interfacial adhesion with PVC matrix.展开更多
基金Funded by National Natural Science Foundation of China(No.51274015)
文摘Fibrous brucite,a kind of brucite with unique structure and physical properties,was modified with stearic acid as a surface modifier.In order to investigate the mechanism of surface modification,the fixation of stearic acid on fibrous brucite and the induced changes in surface properties were studied by using X-ray diffraction(XRD),scanning electron microscopy(SEM),infrared spectroscopy(IR),Raman spectroscopy and thermo-gravimetric analysis(TGA).XRD analysis indicates that the modification of fibrous brucite with stearic acid does not cause any changes in the structure of fibrous brucite mineral.Spectroscopy and thermal analysis show that the surfactant molecules are not only directly adsorbed on the surface of the mineral,but also chemisorbed on mineral surface by forming chemical bonds between the modifier and magnesium hydroxide.
基金supported by the National Natural Science Foundation of China (No. U 1507123)the Foundation from Qinghai Science and Technology Department (No. 2014-HZ-817)
文摘A calcium sulfate whisker (CSW) coated with glutaraldehyde crosslinked chitosan (GACS) was prepared to reinforce polyvinyl chloride (PVC) in this study. The results show that the optimum concentration of both chitosan (CS) and glutaraldehyde (GA) is 0.05 wt%. The tensile strength, impact strength, flexural modulus and vicat softening temperature of the PVC composite with 12 wt% of modified CSW are in- creased by 1 Z5%, 40.4%, 0.8% and 3.8% compared with those of the PVC composite with 12 wt~ of unmodified CSW, and by 2.9%, 42.4%, 2Z1% and 6.8% compared with those of pure PVC, respectively. The dynamic mechanical analysis results indicate that the modified CSW/PVC composite exhibits much higher storage modulus and glass transition temperature than those of unmodified CSW/PVC composite and pure PVC. In addition, the modified CSW/PVC composite also demonstrates good thermal properties with a high rapidest decomposition temperature (Trvd) and char residue. The scanning electron microscopy images of tensile-fractured surfaces show that the modified CSW has a strong interfacial adhesion with PVC matrix.