Development of waste expanded polystyrene flexible coating material in concrete waterproofing

How to deal with the waste polystyrene and rubber has become a key research topic recently. This research attempted to process the waste rubber and waste polystyrene with chemical additives to produce the flexible coating material for concrete waterproofing. Based on the best guess on the configuration of the coating constituents by the grid-point method, the design experimental levels (3 levels) for different coating constituents could be decided by introducing the golden-section ratio. Then, the orthogonal experimental design method L₂₇(3¹³) was adopted by choosing surface-drying time, viscosity, water permeability, tensile strength, pull-elongation rate as orthogonal indicators. Through orthogonal experiment design method, the most influential coating constituents on different indicators were experimentally investigated. The results of the water permeability test showed that the water permeability of the coating was 0 mL and the water resistance was good. The analysis results of the orthogonal table showed that the material factors and levels affecting the tensile strength of the waste EPS flexible waterproof coating were: plasticizer (10.09%), polystyrene (17%), rubber powder (14%) and curing agent (5.1%), and the material factors and levels affecting the elongation of the waste EPS flexible waterproof coating are: plasticizer (2%), curing agent (5.1%), rubber powder (11.91%) and EPS (17%). This result can be used as a reference for adjusting the proportion of waste EPS flexible waterproof coating in the future.