Manufacture of fibrous reinforcements for biodegradable biocomposites from Citysus scoparius

• Published in: Journal of chemical technology and biotechnology (1986) 2011-04, Vol.86 (4), p.575-583
• Main Authors: González, Daniel, Campos, Ana Rita, Cunha, Antonio M, Santos, Valentín, Parajó, Juan Carlos
• Format: Article
• Language: English
• Subjects: Applied sciences; autohydrolysis; biocomposite; broom; Chemical engineering; Citysus scoparius; Cytisus scoparius; Exact sciences and technology; injection molding; PLA
• ISSN: 0268-2575; 1097-4660; 1097-4660
• DOI: 10.1002/jctb.2555

BACKGROUND: Cytisus scoparius samples were processed with hot, compressed water (autohydrolysis treatments) to obtain both fiber-containing solids (suitable as reinforcements for composites) and a liquid phase containing sugar oligomers derived from hemicelluloses. The solid phase from autohydrolysis, mainly made up of cellulose and lignin, was employed for manufacturing polylactic acid (PLA)-based biodegradable composites. The mechanical properties, water uptake and thermal properties of composites were assessed. RESULTS: The hydrolysis of the major hemicellulose polysaccharide components of Cytisus scoparius was interpreted using kinetic models based on sequential pseudo-homogeneous first-order, irreversible reactions. Operating under non-isothermal conditions, the autohydrolysis experiment carried out at up to 215 °C led to the maximum concentration of sugar oligomers (accounting for about 71% of the initial xylan). These compounds can be employed for a variety of purposes, including applications as prebiotics. Composites containing autohydrolyzed fibers presented both improved impact strength and reduced water absorption ability. CONCLUSIONS: Autohydrolysis of Cytisus scoparius led to a liquid phase containing xylooligosacharides with commercial value, and to a solid phase suitable as a reinforcement for PLA-based composites with reduced water retention ability. Copyright