Study On Effection Of N-P Intumescent Flame Retardant Systems Of Polypropylene

Flame retardant is a kind of functional agent that could improve the nonflammability and self-extinguishing of the combustible materials. It is one of important fine chemicals which used in composite materials, it is also very important for preventing the fire hazard and protecting the safety of human being. As the development of the society, research and develop high efficient, nontoxie halogen-free flame retardants is the tendency.Therefore, this thesis is to investigate the influence of N-P intumescent flame retardants on PP. To meet the content flame retardancy, humid resistance and transference of the intumescent flame retardants of PP. This thesis is to investigate the effect of the carbon agent of the intumescent flame retardants on the flame retardancy of the products.In the intumescent flame retardant systems, investigate the effect of carbon agents of different intumesent flame retardants on the flame retardancy of PP. The acid agengt-APP, the LOI is 22 with 40 percent of flame retardant. Comparing the flame retardancy of MEL to MCA, LOI improves with increasing the content of MEL. LOI is 22 with 40 percent of MEL. Due to the unmatching decompose temperature, LOI does not change with increasing the content of MCA. The LOI is 20 with 20～40 percent of MCA. Let's APP cooperate with MEL in PP, the flame retardancy is excellent. The LOI is 24 with ratio of which is 3/1. Adding carbon agents to the flame retardant systems such as ZnO, G₂O₃, MMT, PA6 and PBT can effectively improve the flame retardancy of PP. When the content is 2%, 1 %, 1.5 %, 1.5 % and 4.3 %, LOI is 29,26,29,29,28. It is found that the content of carbon agent is important to enhance the flame retardancy of PP, and there is a optimal content. If the content exceeds that, the flame retardancy would decrease.Using the TGA, DTA, FUR and SEM technique to study the course of decompose of PP, structure and appearance of carbon remains. It is considered that the carbon agent can advance decompose and the content of carbon remains during the process of PP flame retardant products. The compact and equality structure decrease the speed of decompose and is a key factor to heighten the flame retardancy of PP.Though the humid experiment, the result shows that the carbon agent can develop the humid performance of PP, but the range is small and can meet the demand of PP in the humidity condition. The humid performance of product of each carbon agent (ZnO,Cr₂O₃,MMT,PA6 and PBT)is 0.50%,0.81%,0.80%,0.93%,1.20%.The data shows that the flame retardant badly worsen the mechanical properties of PP. The effect of carbon agent is small due to the small content. The primary is APP and MEL.