| Today's world, Expanded Polystyrene plastics (abbreviated as EPS) are used widely day by day. They bring great convenience to people, but at the same time because of their refractory in the nature they have become everyone's talking issues. They do create serious environmental problems. So the people at home and abroad are concerned about their recycling issues. People have reseached these problems thoroughly and extensively. The adhesives and coatings which made by waste formed polystyrene have developed with low energy consumption, simple process, small investment, etc. In this way, we can turn waste into treasure. This will not only bring economic benefits but also bring social benefits.The experiment is divided into three parts. The first part is PS grafting trials. The second part is the preparation of the water-emulsion adhesive. The third part is the preparation of solvent-based wall coatings.The polystyrene is one of non-polar polymer resin materials. Its polar matrix adhesion is poor, So we can graft polar monomer in its main chain to play a modified role. In the experiment we explored that the maleic anhydride (MAH) grafted polystyrene process conditions in toluene-ethyl acetate-chloroform-acetone medium, and optimized by orthogonal test the optimal reaction conditions:BPO1%, MAH3%, the reaction time 3h, temperature 100℃, the adding way of BPO 2:1.Unter the best conditions, the grafting yield is 1.96%,and the grafting efficiency is up to 98.4%; With the poor orthogonal test we analysed influence factors of various reaction conditions.The results showed that size of the order:the amount of initiator-BPO is the first factor,the second is the monomer,the third is the reaction time,last is the temperature;The grafting products were characterized by infrared spectroscopy. Analysis showed that maleic anhydride is a saturated monocyclic form of receipt for PS main chain. This proved that MAH-g-PS copolymer is generated indeed.In the preparation of the water-emulsion adhesives by the waste polystyrene, we systematicly explored the factors such as graft fluid, modifiers, plasticizers, emulsifiers, pigment, filler, water and oil phase ratio how to impact the experiment. As a non-polar polystyrene polymer material, its molecular structure contains rigid, unflexible, brittle benzene. Its adhesion is poor in wood, metal, paper and other polar surface. We must change the polarity of the resin so as to enhance its adhesion.. Through a large number of exploratory experiments, We selected the inexpensive rosin as a modifier. By orthogonal test we determined the optimum ratio of adhesives:the graft fluid 70-75%, plasticizer 1.5-2%, rosin 20-25%, zinc oxide 3-3.5%, emulsifier 2.5-3%. the reaction suitable temperature 80℃, time 2h, the ratio of water-oil appearance 3:1. We compared the PS-modified adhesive with the marketable white latex marketable, and concluded that a lot of indicators of the modified gum is better than commercially available white latex. Finally accounted for the economic cost of the PS-modified adhesive. The adhesives are suitable for wood, tile, metal, paper and other products.In the preparation of the solvent-based paint by the waste polystyrene, we systematicly explored the PS-based materials, modifiers, plasticizers, emulsifiers, pigments how to impact the experiment. According to use requirements, we selected toluene, ethyl acetate,200# gasoline as solvents. Through numerous experiments, we obtained the recipe for the coatings: mixed solvents 60-70%, rosin 20-25%, emulsifier 2-4%, plasticizer 0.5-1.5%, Titanium Dioxide 6-8% and the oxidation Zinc 3-4%, activated calcium carbonate 10-15%. And we measured the performance of the modified coatings, the indicators have reached the country's SO1-3 standard. And their cost accounting were also lower than the commercially available products.
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