Organic epoxy matrices have been widely used in the FRP reinforcing technique, but they have serious disadvantages of poor high-temperature resistance. An inorganic adhesive is invented to replace the organic adhesive...Organic epoxy matrices have been widely used in the FRP reinforcing technique, but they have serious disadvantages of poor high-temperature resistance. An inorganic adhesive is invented to replace the organic adhesive. For the inorganic adhesive at normal temperature and different high temperatures, the microstructure and phase composition are investigated by means of X-ray diffraction （XRD） and SEM respectively. Results show that inorganic adhesive can resist at least 600 ℃ high temperature. Fire-resistance performance of inorganic adhesive can meet the requirements of fiber reinforced polymer （FRP） strengthened RC structures.展开更多
Geopolymers are inorganic adhesive synthesized from industrial waste such as fly ash thus the development of wood geopolymer composite would be a low carbon footprint material.Geopolymers,being a non-formaldehyde adhe...Geopolymers are inorganic adhesive synthesized from industrial waste such as fly ash thus the development of wood geopolymer composite would be a low carbon footprint material.Geopolymers,being a non-formaldehyde adhesive can be used as an alternative binder for wood based composites where environmentally friendly and sustainability of product is important.In this study flyash as precursor is been used in the development of wood geopolymer composite product.Flyash is activated with a combination of sodium hydroxide and sodium silicate solutions at a weight ratio of 1:2.5 for geopolymer formation.The study investigated the properties of wood geopolymer composite made with ratios of wood particle to flyash percentage(23/77),(37/62),(44/55),(50/50)and(57/43).Geopolymer formation was observed by X-ray Diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR).Influence of wood particles in wood geopolymer composite were observed by Scanning electron microscope.The study shows that the water absorption and thickness selling properties of all the formulations of wood geopolymer composites are comparable with the medium density particle board and cement-bonded particleboard according to the IS:3087-2005 standard and IS:12406:respectively.Highest mechanical properties and good bond strength was obtained by the composite containing 23%wood particle ratio with 77%percent flyash.However,still improvement in mechanical properties is needed to achieve the mechanical properties comparable to cement bonded particle board.展开更多
Over the past decades, the urgent need for high strength conductive hydrogels in diverse applications has motivated an unremitting effort to combine the improved mechanical properties of hydrogels with conductive perf...Over the past decades, the urgent need for high strength conductive hydrogels in diverse applications has motivated an unremitting effort to combine the improved mechanical properties of hydrogels with conductive performances. In this work, high strength conductive hydrogels intensified with intermolecular hydrogen bonding are fabricated by in situ mixing poly（2-vinyl-4,6-diamino-1,3,5-triazine-co-polyethylene glycol diacrylates）（PVDT-PEGDA） hydrogels with poly（3,4-ethylenedioxythiophene）-poly（styrenesulfonate）（PEDOT/PSS）. The conductive hydrogels in deionized water exhibit high mechanical performances with compressive strength and tensile strength in the range of 7.58-9.52 MPa and 0.48-1.20 MPa respectively, which are ascribed to the intermolecular hydrogen bonding interactions of diaminotriazinediaminotriazine（DAT-DAT） in the network. Meanwhile, adding PEDOT/PSS can significantly increase both the specific conductivities and equilibrium water contents of the hydrogels. These cytocompatible conductive hydrogels may have a great potential to be used as electrical stimuli responsive soft biomaterials.展开更多
基金Funded by the National Natural Science Foundation of China(No.50678050)
文摘Organic epoxy matrices have been widely used in the FRP reinforcing technique, but they have serious disadvantages of poor high-temperature resistance. An inorganic adhesive is invented to replace the organic adhesive. For the inorganic adhesive at normal temperature and different high temperatures, the microstructure and phase composition are investigated by means of X-ray diffraction （XRD） and SEM respectively. Results show that inorganic adhesive can resist at least 600 ℃ high temperature. Fire-resistance performance of inorganic adhesive can meet the requirements of fiber reinforced polymer （FRP） strengthened RC structures.
基金We thank Indian plywood Industries research and training Institute,an autonomous body of Ministry of environment forest and climate change funded this research project.I thank my co-authors for helping me in the study,analysis,and interpretation of data and in writing the manuscript should be declared.
文摘Geopolymers are inorganic adhesive synthesized from industrial waste such as fly ash thus the development of wood geopolymer composite would be a low carbon footprint material.Geopolymers,being a non-formaldehyde adhesive can be used as an alternative binder for wood based composites where environmentally friendly and sustainability of product is important.In this study flyash as precursor is been used in the development of wood geopolymer composite product.Flyash is activated with a combination of sodium hydroxide and sodium silicate solutions at a weight ratio of 1:2.5 for geopolymer formation.The study investigated the properties of wood geopolymer composite made with ratios of wood particle to flyash percentage(23/77),(37/62),(44/55),(50/50)and(57/43).Geopolymer formation was observed by X-ray Diffraction(XRD)and Fourier transform infrared spectroscopy(FTIR).Influence of wood particles in wood geopolymer composite were observed by Scanning electron microscope.The study shows that the water absorption and thickness selling properties of all the formulations of wood geopolymer composites are comparable with the medium density particle board and cement-bonded particleboard according to the IS:3087-2005 standard and IS:12406:respectively.Highest mechanical properties and good bond strength was obtained by the composite containing 23%wood particle ratio with 77%percent flyash.However,still improvement in mechanical properties is needed to achieve the mechanical properties comparable to cement bonded particle board.
基金financially supported by the National Natural Science Foundation of China(Nos.51325305,51473117 and 21274105)National Key Research and Development Program(No.2016YFC1101301)
文摘Over the past decades, the urgent need for high strength conductive hydrogels in diverse applications has motivated an unremitting effort to combine the improved mechanical properties of hydrogels with conductive performances. In this work, high strength conductive hydrogels intensified with intermolecular hydrogen bonding are fabricated by in situ mixing poly（2-vinyl-4,6-diamino-1,3,5-triazine-co-polyethylene glycol diacrylates）（PVDT-PEGDA） hydrogels with poly（3,4-ethylenedioxythiophene）-poly（styrenesulfonate）（PEDOT/PSS）. The conductive hydrogels in deionized water exhibit high mechanical performances with compressive strength and tensile strength in the range of 7.58-9.52 MPa and 0.48-1.20 MPa respectively, which are ascribed to the intermolecular hydrogen bonding interactions of diaminotriazinediaminotriazine（DAT-DAT） in the network. Meanwhile, adding PEDOT/PSS can significantly increase both the specific conductivities and equilibrium water contents of the hydrogels. These cytocompatible conductive hydrogels may have a great potential to be used as electrical stimuli responsive soft biomaterials.
