A study on suitability of general purpose polystyrene as a binding material in mortar

With large quantities of waste produced on earth, innovative practices to utilize wastes are constantly evolving. Plastic is a major pollutant and its expensive decomposing methods have further encouraged development of alternate solutions. A major form of plastic, Polystyrene, in expanded form is used in an extensive manner to produce lighter weight and environment friendly materials. The study focuses on assessing the suitability of General Purpose Polystyrene (GPPS) as a binding material in mortars with Crushed stone aggregates called Manufactured Sand (M-Sand) instead of cement, so that it satisfies the characteristics of conventional cement mortar used to develop building products. The objective of the study is to obtain a suitable dosage of GPPS as binding material with M-Sand and explore its usability by assessing its compressive strength and durability properties. The trial dosages of GPPS of 10%, 15% and 20% is assumed initially by weight in the mix. A dosage of 15% is chosen as this dosage enables proper mixing to cast test cubes. Tests on compressive strength shows that it varies from 11.16 MPa to 15.82 MPa. It is found that when then the test samples of composite mix of GPPS and M-Sand is heated up to 100±50C, there was a very slight decrease in its compressive strength. The mean water absorption of the test samples was between 0.1% to 5%. The composite mix thus adopted proves as a strong potential binding agent for producing building products. No usage of cement also proves a novelty considering the environmental concerns.