The effect of steam explosion on the production of sugarcane bagasse/polyester composites

This paper describes a pretreatment option to sugarcane bagasse fibers for their use in composite preparation with unsaturated polyester. Sugarcane bagasse fibers modified by (i) steam explosion and (ii) alkali washing after steam explosion, along with (iii) as-received bagasse fibers were characterized. Steam explosion significantly reduced the amount of hemicelluloses and acid-soluble lignin of bagasse fibers, while acid-insoluble lignin increased proportionally. Alkaline washing of steam-exploded fibers removed nearly 60% of their acid-insoluble lignin. Polyester matrix composites containing 10 wt.% of these fibers were prepared by compression molding. Density, thermal stability, water absorption and thermomechanical analysis of the composites containing steam explosion treated bagasse fibers showed improvement in these properties over those of the untreated fiber containing composite. These are explained in terms of the chemical modifications that occurred due to the steam explosion treatments.