Study On Recycling Of Waste Produced In Rubber-Plastics Foaming Process

With the rise of China's comprehensive national strength,people's demand for thermal insulation materials also increases remarkably,which produces more pollutants during the foam formed process.The main pollutants produced in the foaming process of rubber-plastic complex materials are formamide,urea,chlorinated paraffin,DOP,liquid paraffin and other small molecular substances.If these substances are discharged into the water body without any treatment,they will destroy the photosynthesis of aquatic plants and dynamic balance of microorganisms in the water,which ean eause extreme harm to the environment.However,it is troublesome to treat these toxic wastes since their complex composition,high viscosity,heterogeneity and difficult quantification methods.Hence,in the research,the different polarity and water solubility of each component were utilized to classify and separate the toxic substances.In these substances,the water soluble ones have high content of amide groups,which contain strongly activated hydrogen,can react with aldehydes and be used for the modification of phenolic resin as negative groups.Meanwhile,the chlorinated paraffin,liquid paraffin,DOP and other poorly polar substances in pollutants,have good chemical stability and can be used as flexible materials for plasticizers and lubricants of epoxy resin.In the research,the pollutants produced in the rubber-plastic foaming process separated and treated were used in two thermosetting resins.The reuse of industrial waste was realized,during which the secondary pollution in the separation process was avoided.First,oily substances in the rubber-plastic condensate produced in the foaming process of the were removed by activated carbon adsorption,then the amides in the condensate were washed with water to modify the phenolic resin in the next stage.The functional groups of rubber-plastic condensates before and after treatment were analyzed by FI-IR spectra,and the quality of the separated amides was controlled.LPF adhesive,synthesized by phenolic resin which was modified by the water solution of rubber-plastic condensate treated with activated carbon,was compared with PUF adhesive modified by pure urea.When the amount of amide is 0.7 in LPF,the mechanical properties of the adhesive reach the maximum of 30.85 MPa,and the initial decomposition temperature of LPF is 20? higher than that of PUF.Second,the rubber-plastic electric tarching oil produced by the rubber-plastic foaming material process is used as a raw material and treated by activated carbon to adsorb the oily substance.The activated carbon is washed with tap water until the N content in the aqueous solution is reduced to a certain extent.Finally,the oily substance adsorbed in the activated carbon is desorbed with 1,2-dichloroethane,and the organic phase is separated to obtain an ECT plasticizer.The FI-IR infrared spectrum shows that the rubber-plastic electric tar after the activated carbon treatment is basically free of amides.A sample of epoxy resin was prepared using ECT as a plasticizer and compared with epoxy resin which was separately plasticized with DOP and chlorinated paraffin.When the ECT is added at a mass of 10%,the mechanical strength reaches the maximum and the initial decomposition temperature reaches 310?.In summary,the water solution of rubber-plastic condensate and the ECT plasticizer,which were obtained from chemical waste,were applied to two kinds of thermosetting resins after the preliminary treatment by activated earbon.This research not only maintains good mechanical and thermal properties of the original resins,but also reduces the cost of matching use of phenolic resin and epoxy resin respectively.Moreover,it also provides a new method for pollutant treatment and reuse in foaming industry.