Research And Development Of Low Odor Impact-resistant Copolymer Polypropylene For Automobile

With the propose of the concept of automobile lightweight,polypropylene has been one of the most important plastics to replace metals for producing automobiles.Of which,impact copolymer polypropylene has been used to process automobile bumpers,instrument panels,and side door panels owing to good comprehensive performance.However,impact copolymer polypropylene material would produce volatile organic compounds and release pungent odors,which seriously threaten the health of people who drive the automobile.Based on this situation,in this paper,using impact copolymer polypropylene EP508N as the base material,adopting a combination of powder odor pretreatment and melt blending modification method.On the basis of the odor pretreatment of the powder,functional additives such as antioxidants,nucleating agents and deodorants with excellent adsorption properties that have little effect on the odor of the system were used to prepare low-odor,high-performance automotive impact copolymer polypropylene materials,which meet the needs of my country's automotive interiors Materials and other fields have an urgent need for low-odor high-performance polypropylene materials.The main research contents and results are as follows:(1)Using impact-resistant copolymer polypropylene(EP508N)powder as the basic resin,used two treatment methods:hot steam-N₂ treatment and ultrasonic treatment to remove volatile organic compounds from the powder,and compare the smell properties and crystallization properties of the samples that were processed by two treatment methods.The results show that the hot steam-N₂ treatment method can make EP508N powder with lower volatile content,lower odor level and better performance.The VOC(Volatile Organic Compounds)value of sample processed by this method decrease from 812.2?g/g to 495.4?g/g,the FOG value decrease from 495.4?g/g to 320.3?g/g,and the odor level decrease from 5.0 to 3.5.(2)Using two sets of imported and domestic antioxidant systems(1010/168)and three nucleating agents NP-657,EPX-715,HPN-20E to mix with EP508N for research.The results show that the domestic antioxidant system YFK-1010/168 and the nucleating agent HPN-20E,the volatile content,TVOC(Total Volatile Organic Compounds)value,and odor level of the sample are lower.Apart from that,the crystal nucleus density and crystallinity are higher.The domestic antioxidants have favorable odor performance.(3)We determined the optimal dosage of the HPN-20E.The results show that the sample has a lower volatile content,TVOC value,and odor grade when the amount of HPN-20E added is 0.08%.At the moment,the polypropylene possesses the largest crystal nucleus density and the highest crystallinity.The VOC value and FOG value are both relatively lower than the samples without nucleating agent.The nucleating agent can improve the crystalline properties of polypropylene,increase its structural regularity,hinder the movement of volatile small molecules,and increase the difficulty of escaping from the matrix,then improving the odor performance of polypropylene.(4)Using diatomite,nano-Zn O,and porous aluminum silicon deodorant CW-227 to improve the performance of EP508N,and it was found that the EP508N modified with diatomite shows better odor performance.Using HPN-20E and diatomite to improve the performance of EP508N,it is found that when HPN-20E was added at 0.08%and diatomite at0.8%,the VOC value of the sample decrease from 271.2?g/g to 158.8?g/g and the FOG value is decreased from 228.1?g/g to 154.4?g/g;the odor level is reduced from 5.0 to 3.0,and the initial temperature of thermal degradation of the sample is increased from 108?to 216?.The thermal performance of the sample is improved.Maintain satisfied mechanical properties and processing properties.HPN-20E mixed with diatomite could be used to obtain impact-resistant copolymer polypropylene materials for vehicles with low odor and high performance.