Properties of Polyethylene Foam Incorporated with Extracted Lignin from Pulping Black Liquor

Abstract

This research was a study of physical and mechanical properties of polyethylene foam incorporated with various amount of lignin from 5 to 20 phr.The lignin was isolated from black liquor from Kraft pulping using a sulfuric acid at pH 3 and washed with hot water. A Fourier Transform Infrared Spectroscopy (FTIR), Thermo Gravimetric Analyzer (TGA), and Laser Light Scattering were used to characterize the extracted lignin.The preparation of polyethylene foam was carried out using two-roll mill and compression moulding.Visual inspection, density measurement, and Scanning Electron Microscope (SEM) were used to investigate physical properties while compression test and compression set were used to investigate mechanical properties.The average lignin particle size diameter appears to be 31.733 m. The foam density increased slightly with amount of lignin.From SEM micrographs, it exhibited that all PE foams had a closed-cell structure where the cell sizes varied with amount of lignin.Foam incorporated with 10 phr of extracted lignin showed the finest cell distribution with an average cell diameter of 0.51 millimeters.