Preparation And Research Of Microcapsules Flame Retardant And Its Applications In PVC Membrane Structure Material

PVC membrane structure material is taking high strength fabric such as polyester fabric,etc,as the skeleton,then polyvinyl chloride coating material on both sides.It is widely used in architecture,sports,leisure and other fields as the advantage of low cost,excellent toughness,easy processing.Commonly Flexible PVC coated membrane material need to adding plasticizer to improve its softness and processing property,but plasticizer is generally flammable,this is not only greatly reduce the flame retardancy properties of PVC film materials,but also limiting the widespread use of such materials,flexible PVC membrane material in the process of burning will emit a lot of toxic and harmful black smoke,threaten the safety of human life,so It is important to study Flame retardant and the elimination of smoke performance of PVC membrane structure material.In order to reduce the potential fire hazard of PVC membrane structure material,we need to develop a kind of flame retardant and smoke suppression agent which is green environmental protection and high efficiency.Studies have found that tin compounds such as zinc stannate(ZnSnO3)can be used as a highly effective flame retardant and smoke suppression agent for halogen containing polymer materials.Which added amount is 5%~10%,but because of its poor dispersion in the matrix and high-cost,so the application is limited.In order to improve the flame retardant efficiency of ZnSnO3 and its dispersion in polymer matrix,at the same time reduce the cost of the use of flame retardant,we find a practical and feasible method that the magnesium hydroxide(MTH)coated with ZnSnO3 and melamine formaldehyde resin(MF)and MTH double coated ZnSnO3,synergistic flame retardant system of Mg-Zn-Sn,N-Mg-Zn-Sn.In this paper,the microcapsule flame retardant was prepared the environmental protection flame retardant zinc stearate(ZS)was used as the core material,and the magnesium hydroxide and melamine formaldehyde resin was used as wall material.Using Fourier transform infrared spectroscopy,X-ray powder diffraction(XRD),transmission electron microscope(TEM),field emission scanning electron microscope(SEM),thermal gravimetric analysis(TGA)and other methods to carry out a series of characterization.Results show that the particle size of the single layer and double layers coated zinc stannate microcapsule is 50nm~250nm.It has Layered structure with core-shell structure,and its thermal stability has also changed.The microcapsule flame retardant was added into PVC slurry by mechanical mixing method,and then use it toprepare flame retardant PVC film,Using vertical horizontal combustion method,the limit oxygen index method(LOI),smoke density test(SDR),thermal gravimetric analysis(TGA),scanning electron microscope(SEM)and other methods to test the performance of flame retardant and smoke suppression.Results show that the LOI value of the PVC membrane material increase to 27% when the content of microcapsule flame retardant is about 8%.At the same time,the remaining length of combustion is increased significantly in the vertical horizontal burning test,the Smoke density decreased to 50%,which is show excellent flame retardant and smoke suppression performance.Finally according to scanning the scanning electron microscopy,tensile test and rotary rheometer,the distribution of flame retardant in the matrix and its effect on the mechanical properties of the matrix were studied.Research results show that double layers coated zinc stannate microcapsule flame retardant in PVC membrane material dispersion is better than the pure magnesium hydroxide and zinc stannate,which has less aggregation and distribution more uniform.Meanwhile double layers coated zinc stannate microcapsule on the mechanical properties of PVC matrix effect is smaller than pure magnesium hydroxide and zinc stannate,it shows better compatibility with the matrix.The effect of double layer microcapsule on the viscosity of PVC slurry is the least,it will not greatly increase the viscosity of PVC slurry,which less influence on the production and processing technology and increase the practical application range...