Study On Super Low Density Class A Fireproof And High Performance Composite Insulation Material

A composite insulation material with ultra-low density and class a fire resistance is prepared by compounding cement and polystyrene foam.It is applied to the external thermal insulation system,and has dual characteristics of energy saving and fire prevention.In this paper,the composite technology of modified cement-based materials and modified EPS foam is systematically studied in three aspects:the preparation of matrix materials,the modification of interface and the flame-retardant modification of composite insulation board.In this paper,orthogonal design method was used to optimize the matrix material formula from three factors:polymer type,expansion component and polymer content.The optimal scheme of medium content polyacrylate and U-type expansion agent was determined.Composite insulation board with tensile strength?0.10MPa and compressive strength?0.15MPa was prepared.The result of Mercury intrusion analysis shows that although polyacrylate improves the total porosity of matrix materials,the improvement of mechanical properties of matrix materials is due to the refinement of pore structure of cement-based materials.In order to improve the problems of high density,high thermal conductivity and poor waterproof performance of composite insulation board,the performance of composite insulation board matrix material was optimized by adding polyvinyl acetate instead of polyacrylate and adding glass beads.Although the mechanical properties of the composite insulation board were sacrificed,the density and thermal conductivity of the composite insulation board were reduced by 28%and 14%respectively by combining the optimized particle size,density and interface pretreatment technology of EPS.In view of the problem that the thermal conductivity of composite insulation board is still on the high side,the interfacial bonding modifier was optimized by mixture design method.Through the nonlinear regression analysis of tensile strength of composite insulation board,the interfacial bonding modifier with polyvinyl acetate:polyacrylate=1:9 was finally determined.The optimal modifier was used to treat the composite insulation board,which effectively improved the interfacial adhesion between EPS particles and matrix.The thermal conductivity of composite insulation board is?0.050w/(m·K)due to the reduction of the amount of matrix material.In order to improve the fire retardant performance of composite insulation board,the effects of EPS foams,particle size and flame retardants on fire retardant performance of composite insulation board were studied.Through the optimization of particle size and type of EPS,combined with flame retardant modification technology,the composite insulation board with apparent density?180kg/m~3,thermal conductivity?0.050w/(m·K),and with A-class fire resistance performance was successfully prepared.