Use of additives to improve bonding strength of the adhesive prepared from used polymer: Sustainable management approach

In the present study, value added and environment-friendly adhesive material is prepared from post-consumer (used) expanded polystyrene (PCEPS) for possible applications. The physico-chemical properties of the prepared adhesives, such as, solubility, viscosity, shear strength/bonding strength, moisture content are estimated as per the standard procedures. The study shows that PCEPS is sufficiently soluble in various solvents, such as, m-xylene, n-BA, THF, MEK etc. Various substrate materials, such as, paper, wood, cement and clay bricks, and ceramic tiles are considered to check the suitability of the prepared adhesive to bind them. The study indicated that the prepared adhesive (PCEPS-MEK) is suitable to bind various substrate materials mentioned above. The study further extended to bind the metal (iron) substrates with PCEPS adhesive. From the results, it is noticed that PCEPS adhesive offered lower bonding strength over commercial adhesive Araldite. Therefore, the study furthermore extended to improve the PCEPS adhesive bonding strength using two different additives. The result implied that the bonding strength of the EPS adhesive decreased drastically with the increase of Additive-1 (A1). However, the bonding strength of EPS adhesive increased in presence of Additive-2 (A2) and its loading. Around 69% increment in bonding strength of PCEPS adhesive is obtained when the Additive-2 loading is increased up to 50 wt% under present experimental conditions. Therefore, Additive-2 can be used as one of the suitable additives to improve the PCEPS adhesive properties especially bonding strength.