Application Of Waste Bakelite In Epoxy Resin And Nitrile Butadiene Rubber

With the progress of science and technology and the development of economy,the replacement of products is faster and faster.Every year,a large number of household appliances and electrical products are scrapped,resulting in a large number of waste bakelite.At present,it is mainly treated by incineration and landfill,resulting in serious waste of resources and environmental pollution.With the rising price of raw materials and the aggravation of environmental pollution,it is of great significance to realize the recycling of waste bakelite.In this paper,waste bakelite powder(WBP)was added to epoxy resin(EP)and nitrile butadiene rubber(NBR)as filler.The structure and properties of the composites were studied.Waste bakelite collected from the factory was crushed and ball milled to obtain WBP with the required particle size.The basic properties of WBP were studied by various characterization methods.The results showed that WBP was mainly composed of thermosetting phenolic resin,wood powder and glass fiber.There are a lot of hydroxyl groups on the surface of WBP,which provide reaction groups for its modification.The curing kinetics of EP system was studied by non-isothermal DSC,and the curing process of EP was determined.KH550 modified WBP(KH550-WBP)was prepared.The WBP before and after KH550 modification was added to EP.The structure and properties of the composites were studied.The results showed that the mechanical properties of the composites decreased with the addition of unmodified WBP.Comparing the effect of WBP modified by different dosage of KH550,it was found that the best dosage of KH550 is 3%of the quality of WBP.Comparing the mechanical properties of the composites with different KH550-WBP contents,it was found that when the KH550-WBP content is 25 wt%,the mechanical properties of the composites are the best,the tensile strength is 59.2 MPa,the flexural strength is 92.59MPa,the flexural modulus is 3029.7 MPa,and the impact strength is 13.19 k J/m~2,which is9.4%,2.1%,27.2%and 29.4%higher than that of pure EP respectively.At the same time,the thermomechanical properties of the composites are effectively improved.In view of the good oil resistance of bakelite,the study of NBR filled with WBP was carried out.KH550-WBP and Si69 modified WBP(Si69-WBP)were prepared.WBP,KH550-WBP and Si69-WBP were added to NBR respectively.Their effect on the structure and properties of NBR composites were studied.The results show that when the filler content is 40 phr,the tear strength of NBR/Si69-WBP composites is 267.6%higher than that of unfilled NBR composites,the Shore A hardness of NBR/KH550-WBP composites is 36.4%higher than that of unfilled NBR composites.KH550-WBP has good dispersion in rubber and shows good interface bonding.In order to further strengthen NBR/WBP composites,carbon black was introduced to prepare NBR/CB/WBP composites.The results showed that the mechanical properties of NBR composites were effectively improved with the increase of carbon black proportion.But the change of carbon black proportion had little effect on the crosslinking density of NBR composites.With the increase of WBP ratio,the heat and oxygen aging resistance and oil resistance of NBR composites were improved.