The Use of Recycled Polyethylene in Water‐Oil Emulsion for Lightweight Concrete

Abstract

This study was to determine the suitability of recycled waste polyethylene (WPE) processed into water‐oil emulsion for lightweight concrete applications. The processed WPE in the form of polyethylene emulsion (PE‐e) is to promote physical interaction between the polymeric material and the cementitious matrix. The PE‐e used was also to partially replace concrete mix composition by PE‐e_1, PE‐e_2.5, PE‐e_5, and PE‐e_10 percents for reference concrete and to introduce plasticity into the mechanical behaviour of the concrete. The PE was processed into PE‐e to promote affinity for water, and this hydrophilicity was prominent in PE‐e_1 and PE‐e_2.5 percent concretes. Concretes with PE‐e_1 and PE‐e_2.5 percent formed good miscibility with the cementitious matrix. The density of the PE‐e concrete decreased to 13.68% with 10% PE‐e at 28 days. The replacement of mix constituents of PE‐e_1, PE‐e_2.5, and PE‐e_5 percent induced elastic to plastic behaviour in the concrete coupled with low water absorption. The FTIR data showed characteristic peaks of 3378 cm -1 , 1740 cm -1 , and 1148 cm -1 in the PE‐e. Using optical microscopy, it was shown that the PE particles were homogenously dispersed in the concrete matrix. The study shows the feasibility of using PE‐e_1 percent to produce structural lightweight concrete and up to PE‐e_10 percent for nonstructural applications mainly for light non‐load‐bearing partitions.