Water absorption and thickness swelling properties of silica aerogel infused sugar palm fiber/polyester composites

Abstract

Using natural fibres as reinforcements in composites provides an inexpensive green alternate to its synthetic counterpart. In a similar scope, to enhance the usability of sugar palm fibres (SPF) in composites, various weight percentages (1% to 5%) of silica aerogel (SA) were infused in SPF reinforced unsaturated polyester composites. The samples were prepared using hand layup procedure followed by hot pressing at 80°C for 30 minutes. The physical properties such as water absorption and thickness swelling characteristics of the composites were investigated. The specimen of water absorption and thickness swelling were exposed to water absorption for a total of 90 days and measured on alternate days in first week. Later, the readings were taken on a weekly basis until the 3rd week and bi-weekly for the rest of immersion time. Pure SPF composites showed lowest water absorption and thickness swelling and it increased with addition of SA. The highest water absorption was recorded up to 12 % and thickness swelling was 7% in 5% SA composites. SA showed its hydrophilicity character, but the percentage of water absorption and thickness swelling is very less.