Effects of lignin content on the properties of lignocellulose-based biocomposites

• Published in: Carbohydrate polymers Vol. 66; no. 4; pp. 537 - 545
• Main Authors: Le Digabel, F., Avérous, L.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 2006; Elsevier Science; Elsevier
• Subjects: Applied sciences; Biocomposite; Biodegradable; biodegradable products; Chemical Sciences; composite polymers; Composites; equations; Exact sciences and technology; filling materials; Forms of application and semi-finished materials; lignin; Lignin extraction; lignocellulose; Lignocellulose fillers; mechanical properties; Polymer industry, paints, wood; Polymers; Technology of polymers; thermal properties; Wheat straw; Lignocellulose fillers; Biodegradable; Biocomposite; Lignin extraction; Wheat straw; Grain size analysis; Fiber reinforced material; Mechanical properties; Plant fiber; Composition effect; Lignocellulosics; Tensile property; Experimental study; Composite material; Transformation temperature; Ester copolymer; Heat of transformation; Butene terephthalate copolymer; Surface properties; Surface tension; Adipate copolymer; Filler; Surface energy
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2006.04.023

The paper is focused on the analysis of the behaviour of biocomposites (biodegradable composites) which are reinforced with different fillers fractions, with varying lignin contents. These materials have been carried-out by extrusion and injection moulding. The matrix, an aromatic copolyester (polybutylene adipate- co-terephthalate), is biodegradable. The lignocellulose fillers are a by-product of an industrial fractionation process of wheat straw. From the raw agro-material and by lignin extractions, various fillers fractions have been obtained by varying the fractionation conditions, both on the liquid media (aqueous or organic) and on the temperature. The fillers lignin contents vary from 30 to 14 wt% with a resultant increase of the cellulose content. We have analysed the impact of the different extraction conditions on the fillers surface and size distribution, and also on the final thermal and mechanical properties of the biocomposites. These materials present significant differences of behaviour which can fulfil some requirements for applications, such as non-food packaging or other short-lived applications (agriculture, sport …) where long-lasting polymers are not entirely adequate.