Influence of Cu2+-organic montmorillonites on thermal decomposition and smoke emission of Poly (vinyl chloride) by Cone calorimetric study

摘要

Cu2+-organic montmorillonites were prepared by modifying Na+ montmorillonite with silane coupling agents and cupric chloride. The efects of Cu2+ -organic montmorillonites on decomposition and smoke emission of poly (vinyl chloride) (PVC) in the flaming mode were investigated out using a cone calorimeter (CONE) at an incident heat flux of 25kW m-2. The experimental data demonstrated that Cu2+ -organic montmorillonites prepared are new effective smoke suppressants. They clearly promoted an early HCl-elimination, cross-linking reactions and char residue based upon decomposition parameters of mass loss(ML), mass loss rate (MLR) and time of initial decomposition (tinitial). Cu2+-organic montmorillonites decreased peak- heat release rate (pk-HRR), total heat release (THR), peak-smoke production rate (pk-SPR), total smoke production (TSP) and smoke extinction area (SEA) of flaming process obviously. And the reducing smoke efficiency of Cu2+-organic montmorillonites is the best. However, the content of cupric ion is only 0.6～0.8% in Cu2+-OMMTs, and 0.03～0.04% in PVC composites, they can make the reducing smoke efficiency reach 45～50%. This further demonstrates that Cu2+ ion is an effective smoke suppressant element of PVC.