Study On Preparation Of Expandable Flame Retardant Polystyrene/Silica Aerogel Core-shell Particles And Composite Thermal Insulation Board

Expandable polystyrene is a very common polymer materials. because of its low waterabsorption, light weight, excellent excellent insulation and dielectric properties, goodmechanical strength and toughness,corrosion resistance, obtained in the external wallinsulation system a wide range of applications, but its high thermal conductivity anddrawback flammable relative organic foam phenolic resin and polyurethane thermal insulationmaterial, has become the bottleneck of the development of polystyrene. To improve theadiabatic performance of polystyrene foam board and solve the flame retardant performanceIn this paper,have studied twe kinds of flame retardant modified polystyrene foam insulationmaterials. Firstly, Using super thermal insulation material of SiO2aerogel and polystyrene fororganic and inorganic composite, have prepared flame-retardant polystyrene granule bysuspension polymerization method. Secondly, Through the distribution of organic andinorganic compound flame-retardants and flame-retardant polystyrene beads common foammolding, preparation of a coated type of foam.The first step this paper researched the suspension polymerization process offlame-retardant polystyrene composite particles and the subsequent dipping process. And theinfluence of polymerization reaction by oil and water、dispersant system、initiating agent andmixing speed were discussed, the influence of impregnation technology by vesicant wasanalysied, the influence of grain comprehensive performance by SiO2aerogel adding amount,HBCD/Sb2O3content were studied. The results show that: complex particle have smallaverage particle size, and concentrate particle size distribution,When styrene is100parts,deionized water is100~450parts, PVA solution (5%) is5parts, tricalcium phosphate is2~2.5parts, BPO is1.5~2parts and two to join, stirring speed is350~400r/min. Compositeparticles in conformity with the requirements,when the amount of foaming agent added to12~16%; the time of thermal conductivity coefficient can reach0.0248w/（m k）, when theSiO2aerogel add adding amount of1.6~2.0%; the bead self-extinguishing time is less than1second, when HBCD adding amount was2.4~3.6%, Sb2O3content of0.8~1.2%.The second step this paper researched two footwork preparation flame-retardantcomposite particles of pretest bubble technique and molding process of a coated type of foam. And the influence of beads performance by the prefoam pressure and flux of vapor time; theinfluence of the comprehensive performance of composite foam plate by distribution of flameretardant. The results show that: When the prefoam pressure is0.4MPa, flux of vapor time is45s, beads density is0.02~0.025g/cm3, ratio is about25times, organic flame retardants Acontent is17.5%, inorganic flame retardants B adding amount is8%, inorganic flameretardants C adding amount ias2%, the inorganic flame retardants D adding amount is2%,the comprehensive performance of composite foam plate is as follows: Limit oxygen index(LOI) for33.1, the bulk density for40.88kg/m3, the tensile strength for0.2237MPa,bibulous rate for3.19%.