Effects of temperature on the compressive properties of extruded recycled unplasticized polyvinylchloride

Abstract

Recycled plastics, over the years, are believed to be inferior to virgin plastics. In this work, compression test was carried out on virgin and recycled uPVC plastics at different temperatures, from 25°C to 130°C at intervals of 15°C, to determine and to compare their compressive properties. The specimens were heat treated in an electric oven for one hour, for the various temperatures of interest, and then tested at room temperature. Prior to heat treating and testing, the specimens were conditioned for over 40 hours at temperatures of 26 1°C. This is to ensure substantial equilibrium under room condition and to make it possible to obtain reproducible results, regardless of previous history of exposure of the specimens. The results show that recycled uPVC exhibits better rigidity for all the temperatures considered except at 40°C where a stress at yield of 0.5919MPa and 0.6131MPa was recorded for recycled and virgin uPVC, respectively. Recycled uPVC shows poor dimensional stability at temperatures between 25°C and 85°C with great improvement at 100°C and 115°C (16.98% and 22. 96%, respectively) as compared to strain at fracture of 37.13% and 42.39%, respectively for virgin uPVC. Recycled uPVC was found to be a reliable, and in some cases, a better alternative to virgin uPVC.

Journal of Applied Science, Engineering and Technology Vol. 5(1&2) 2005: 5-10