What is the EVA material?

EVA refers to ethylene-vinyl acetate polymer. It is a common material with high crystallinity and good flexibility, and is widely used in many fields such as foamed shoe materials and functional shed films.

The performance of EVA is better than that of PE, mainly in elasticity, flexibility, gloss, air permeability and so on. In addition, its environmental stress cracking resistance is improved, and its tolerance to fillers is increased. Compared with PE, adding more reinforcing fillers can avoid or reduce the decline of EVA mechanical properties. EVA can also have new uses through modification, and its modification can be considered from two aspects: first, EVA is used as the skeleton for grafting other monomers; Secondly, EVA was partially alcoholized.

EVA emulsion can be used as cement modifier, and cement is one of the most widely used materials in construction engineering. However, simple cement products have the disadvantages of easy cracking and poor water resistance, impact resistance and acid resistance, which affect the practical effect of cement to some extent. Since the 1920s, people have been devoted to the study of cement modification. With the deepening of research, it is found that many synthetic emulsions have good effects on cement modification, such as polyvinyl acetate emulsion, acrylic emulsion, styrene-butadiene emulsion, EVA emulsion and so on.

Among them, EVA emulsion is widely used in civil engineering as a new material because of its good water resistance, acid and alkali resistance, weather resistance and lower price than similar products. In recent years, for the sake of environmental protection, EVA redispersible emulsion powder has gradually appeared in the market, and gradually replaced the position of EVA emulsion in cement modifier, becoming the main product of main cement modifier.

References:

EVA plastic raw materials-Baidu Encyclopedia