Preparation And Properties Of High Impact Polystyrene With Synergistic Flame Retardant

High impact polystyrene(HIPS)has the advantages of easy processing and good dimensional stability,etc.It is widely used in housing packaging for household appliances,electronic products and military supplies.Its flame retardant performance is poor,which greatly limits its application.Synergistic flame retardant can improve the comprehensive performance of flame retardant HIPS.In this paper,three new flame retardant systems were designed and prepared,which were applied to the flame retardant modification of HIPS.The mechanical,rheological and flame retardant properties of flame retarded HIPS composites were measured.The related mechanisms were discussed in detail.This paper mainly includes the following parts.Based on the principle of synergistic flame retardant effect between P-N-Si multiple elements,silicone powder(GM)and intumescent flame retardant(IFR)were used in synergistic flame retardant HIPS.The effects of GM and IFR on the mechanical,rheological and flame retardant properties of the prepared HIPS composites were studied.The experimental results showed that there was a synergistic effect between GM and IFR.GM could act as a compatibilizer in the matrix,which promoted the dispersion of GM and IFR in the HIPS matrix.Compared with the HIPS/IFR composite in which only IFR was added,the mechanical and flame-retardant properties of HIPS/IFR/GM composites were significantly improved.When 2wt%GM and 33wt%IFR were added,the oxygen index value(LOI)of the composite material reached 31%(Meeting the flame retardant requirements of General Specification GJB4853-2003 for Naval Gun Ammunition Packaging(LOI=30%))and vertical combustion(UL-94)was V-0 level.When 4wt%GM and26wt%IFR were added,the tensile strength of the composite material was 26.36MPa and the UL-94 level reached V-0,which met the requirements of GB/T 24150-2009special flame retardant HIPS material(FR 40,UL-94 V-0 level,the tensile strength?25MPa).The composites had practical application value.According to the barrier and catalytic char formation effects of the layered double metal hydroxide(LDH),CoAl-LDH was synthesized and used as a synergist with IFR in the flame retardant HIPS.The results found that the introduced CoAl-LDH could effectively catalyze the cross-linking of polymers to char,indicating the synergistic flame retardancy with IFR.When 0.1wt%CoAl-LDH and 29.9wt%IFR were added,the mechanical properties of the composites were improved.The tensile strength reached 24.30MPa and the impact strength was 3.04 k J/m~2.When0.3wt%CoAl-LDH and 29.7wt%IFR were added,the LOI of the composite material reached 28.5%and UL-94 reached V-0 level.Based on the characteristics of organic-inorganic hybridization and catalytic action of organic metal framework materials MOFs,Co Zn-ZIF synthesized and used as a synergist with IFR in the flame retardant HIPS.Its effects on the perfirmances of HIPS were studied.The results showed that the addition of Co Zn-ZIF improved the mechanical and flame retardant properties of the HIPS composites.When 0.5wt%Co Zn-ZIF and 29.5wt%IFR were added,the tensile strength of the composite material was 23.18MPa and the impact strength was 4.83k J/m~2.The LOI was 30.5%and UL-94 reached the V-0 level for the composite material.The composite materials met the flame retardant requirements of General Specification GJB4853-2003 for Naval Gun Ammunition Packaging(LOI=30%).