Preparation And Properties Of PP/(LLDPE/EVA)-g-AN/NBR Dynamically Vulcanized Oil-resistant Cable Material

Polyolefin(PO)materials have good electrical properties,mechanical properties,and processability,and are rich in sources,so they are widely used in the field of wire and cable.However,PO has poor oil resistance,which limits its application in the field of oil-resistant environmental cables.The research on PO oil-resistant cable materials has become a hot topic of research.Based on this,this paper studies the process and graftingkineticsof(LLDPE/EVA)-g-AN,andthenprepares PP/(LLDPE/EVA)-g-AN/NBR through dynamic vulcanization,and studies the oil resistance of the cable material,Electrical properties,mechanical properties and micro-morphological characteristics,and lay a solid foundation for the preparation of high-performance and oil-resistant cable materials.In this paper,(LLDPE/EVA)-g-AN was prepared by melt grafting,and the e xperimental process was optimized by a uniformly designed experimental method,and the infrared spectroscopy was used to characterize the grafting kinetics.The results show that:(1)The initiator dilauroyl peroxide(LPO)has a better initiati on effect than bi-tert-butyl dicumyl peroxide(BIPB);the effect of trimethylolprop ane trimethacrylate(TMPTMA)The promotion effect is the best;(2)Grafting pr ocess:temperature is 160?,initiator LPO content is 0.4wt%,AN monomer cont ent is 6wt%,catalyst content is 2wt%,and the mass ratio of LLDPE/EVA is 60/40;In the infrared spectrum of the grafted product,there is a cyano peak at 2240 cm^-1,indicating that AN was successfully grafted onto EVA.(3)The graftin g reaction rate is 0.87 power to the monomer content,0.36 power to the initiato r content,and the temperature obeys the Arrhenius equation.The activation energ y of the grafting reaction Ea=23.78k J/mol.PP/(LLDPE/EVA)-g-AN/NBR was prepared by dynamic vulcanization,and the effect of dynamic vulcanization process(temperature,speed,BIPB content and NBR content in PP/NBR)on the oil resistance and mechanical properties of the vulcanized product was studied.,And then determine the vulcanization process.The microstructure and morphology of the dynamic vulcanization product were analyzed by infrared spectroscopy and scanning electron microscopy,and the influence of the amount of grafting and grafting rate on the oil resistance,mechanical properties and electrical properties of the product was studied.The results show that:(1)The influence of temperature,rotation speed,BIPB content and NBR content on oil resistance and mechanical properties first increases and then decreases.The best vulcanization process:temperature is 190?,rotation speed is 50r/min,and BIPB content is 6wt%The NBR content is 20%;(2)The C=C characteristic stretching vibration peak(1620 cm^-1)of NBR in the dynamic vulcanization product is obviously weakened,which proves that the dynamic vulcanization is basically completed;(3)As the grafting rate and With the increase of the dosage,the oil resistance of the dynamic vulcanization products(resistant to IRM903 fuel oil and IRM902 mineral oil)is gradually increased and first increased and then decreased.(4)As the grafting rate increases,the tensile strength,elongation at break,volume resistivity,breakdown field strength,dielectric constant and loss of the product all increase first and then decrease,while the elastic modulus gradually decreases..(5)With the increase in the amount of grafts,the tensile strength,elongation at break,volume resistivity,breakdown field strength,dielectric constant and loss of the dynamic vulcanization product first increase and then decrease,but the elastic modulus Gradually decrease;(6)When the amount of graft is 5wt%and the grafting rate is 1.91%,the overall performance of the material is the best:the material is resistant to the mass,volume,tensile strength and elongation at break of IRM903 fuel and IRM902 mineral oil The rate of change is as follows:mass change rate:19.85%,15.37%;volume change rate:23.22%,21.56%,tensile strength change rate:17.92%,14.63%;change rate of elongation at break:24.52%,19.64%.Other properties such as the maximum volume resistance of 3.98×10¹³?·m,the maximum dielectric constant of2.04,the maximum breakdown field strength of 23.39kv/mm,the maximum tensile strength of 20.79MPa,and the maximum elongation at break of 99.75%.