Preparation Of Reactive Flame-retardant Master (MPNA And MPPB) And Its Modified Flame Retardant Polyamide66

Polyamide 66(PA66)possesses excellent mechanical and processing properties,which was one of the most widely used engineering plastics.However,applications of neat PA66 products were limited seriously by its flammability.Accordingly,it is of great significance to research on flame retardant modification of nylon 66.The traditional methods of flame retardant modification mainly contain additive type and reactive type.The two methods have their own pros and cons respectively.The additive type flame retardant method has poor flame retardancy efficiency,but it used easily.The reactive flame retardant method has high flame retardancy efficiency,but it is currently in the laboratory research stage.Combined with a series of advantages of traditional flame retardant modification methods,this paper created a new flame retardant modification method.Firstly,reactive flame retardant master was prepared reference to the fundamental of reactive flame retardant.Furthermore referring to the added flame retardant modified method,the flame retardant master was added to pure PA66 for modifying its flame retardant.This method can expand the scope of the practical application of reactive flame retardant.And the reference for industrial application of reactive flame retardant modification was provided by this new method.In this paper,the reactive flame retardant master MPNA was prepared by using flame retardant bis-(p-benzoic acid)-phenyl-phosphoramide and PA66 salt as raw materials.The reactive flame retardant master MPPB was prepared by using PA66 salt and the flame retardant poly-N-aniline-phenyl-phosphoramide as raw materials.The flame retardancy of PA66 was modified by the prepared reactive flame retardant master.Finally,flame retardancy,thermal stability and mechanical properties of the flame retardant PA66 were investigated.(1)The flame retardancy of PA66 was modified by the flame retardant master MPNA.When the flame retardant content of the prepared flame retardant PA66 is 7.5wt%,its UL-94 and LOI reached V-0 level and 30.2,respectively.The initial decomposition temperature is increased from 334? to 372?,and the maximum decomposition temperature is raised from 427? to 455?.The tensile strength and elongation at break decreased by 8.3% and 9.8%,and the impact strength decreased by 0.57 MPa.It is indicated that the use of flame retardant master MPNA enhances the flame retardancy and thermal stability of PA66,and has little effect on the mechanical properties.(2)The flame retardancy of PA66 was modified by the flame retardant master MPPB.When the flame retardant content of the prepared flame retardant PA66 is 7.5wt%,its UL-94 and LOI reached V-0 level and 30.4,respectively.The maximum decomposition temperature is raised from 427? to 462?.The tensile strength and elongation at break decreased by 7.6% and 10%,and the impact strength decreased by 0.87 MPa.It is indicated that the use of flame retardant master MPPB enhances the flame retardancy and thermal stability of PA66,and has little effect on the mechanical properties.(3)Two kinds of flame retardant master were used to modify the flame retardancy of PA66.When the flame retardant content of the prepared flame retardant PA66 is 7.5wt%,its UL-94 and LOI reached V-0 level and 31.4,respectively.The initial decomposition temperature is increased from 334? to 375?,and the maximum decomposition temperature is raised from 427? to 467?.The tensile strength and elongation at break decreased by 6.9% and 9.5%,and the impact strength decreased by 0.47 MPa.It shows that the synergistic use of two kinds of flame retardant master is superior to the flame retardant modification of PA66 by using a kind of flame retardant master alone.