Preparation And Properties Of Flame Retardant Rubber Materials

The flame retardant modification methods of rubber are mainly divided into chemical modification and physical blend modification.Among them,the physical blending modification is physically blended with a rubber material excellent in flame retardancy,and on the other hand,an additive flame retardant is added during kneading.In this paper,a new flame retardant rubber material with good physical and mechanical properties,excellent flame retardancy and environmental friendliness is prepared by physical blending modification.Firstly,CR/NR and CSM/NR blend materials were prepared respectively.The blending ratio of rubber compound,the type of flame retardant,the processing property of compatibilizer,comprehensive mechanical properties,aging resistance,medium resistance,low temperature performance,The effect of flame retardant performance was obtained.Finally,EPDM/EVM halogen-free flame retardant blending materials were prepared.The effects of EVM dosage,type and ultrafine magnesium hydroxide addition on the processing properties,mechanical properties and flame retardancy of the blended materials were studied.The thermal stability and combustion properties of the materials are analyzed by means of a cone calorimeter,an oxygen index meter,a thermogravimetric analyzer,and the like.Research indicates:In CR/NR blending materials,the content of neoprene increases,the tensile strength and elongation at break of the material decrease,the tensile stress and hardness increase,the elasticity and low temperature resistance decrease,but the aging resistance and flame retardancy improve..The addition of epoxidized natural rubber(ENR)as a compatibilizer can significantly improve the compatibility of neoprene and natural rubber and improve the mechanical properties of the material.Aluminium Hydroxide/Zinc Borate/Red Phosphorus: The 50/20/10 flame retardant system can best improve the flame retardant properties of CR/NR blends.In CSM/NR blends,CSM content increases,material processing fluidity deteriorates,hardness and tear strength increase,tensile strength and elongation at break decrease first and then rise,oil resistance,heat-resistant air Aging performance and ozone aging resistance are improved.At the same time,increasing the blending ratio of CSM can improve the oxygen index of CSM/NR blending materials,improve the flame retardant performance,and comprehensively consider the mechanical properties and flame retardant properties.When the CSM content is 65 parts,it can achieve better flame retardant performance at the same time.Mechanical properties.The use of epoxidized natural rubber as a compatibilizer can significantly improve the compatibility of CSM/NR blends.By studying the effect of flame retardant on the mechanical properties and flame retardancy of CSM/NR blends,we found that the flame retardant efficiency of single flame retardant is lower than that of various flame retardants;the smaller the particle size of flame retardant,The better the dispersion,the higher the flame retardant efficiency,and the smaller the influence on the mechanical properties of the blended materials;The relationship between the mechanical properties of EPDM/EVM blends and the blending ratio of EVM: the blending ratio of EVM increased,the tensile strength first increased and then decreased,the elongation at break decreased,and the hardness of blended materials increased.% set tensile stress increases.For the tearing performance,when the amount of 06 B added is less than 60 parts,the tear strength increases with the increase of the EVM blending ratio.When the amount of 06 B added is more than 60 parts,the tear strength decreases with the EVM blending ratio;The relationship between the mechanical properties of EPDM/EVM blends and the amount of 06 B added: As the amount of 06 B increases,the hardness of the material increases and the elongation at break decreases.For tensile strength: when the EVM content is less than 25 parts,the amount of 06 B increases,and the tensile strength of the blended material increases;when the EVM content is higher than 25 parts,the amount of 06 B increases,and the tensile strength of the blended material decreases.For tearing performance: when the EVM content is less than 47 parts,the addition amount of 06 B increases the tearing property of the blending material firstly and then decreases;when the EVM content is higher than 47 parts,the addition amount of 06 B increases the tearing property of the blending material;The relationship between the flame retardancy of EPDM/EVM blends and the blending ratio of EVM: the EVM blending ratio increases,the maximum smoke generation rate of the material decreases,the heat release rate and the total heat release rate decrease,but the effect is small,and the oxygen index rises slowly.high.The relationship between the flame retardant properties of EPDM/EVM blends and the amount of 06 B added: the amount of 06 B added increases,the heat release rate of the material,the total heat release rate and the maximum smoke release rate decrease,the luminous flux per unit area increases,the hardness increases,and the oxygen index increases.For each additional 10 parts of 06 B,the oxygen index of the blended material is increased by about 1.5.06 B can delay the thermal decomposition of the blended material and improve the thermal stability of the EPDM/EVM blend.