Biocomposites based on plasticized starch: thermal and mechanical behaviours

• Published in: Carbohydrate polymers Vol. 56; no. 2; pp. 111 - 122
• Main Authors: Averous, L., Boquillon, N.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 04.06.2004; Elsevier Science
• Subjects: Applied sciences; biodegradable products; cellulose; Cellulose fibres; Composite; composite polymers; Composites; Exact sciences and technology; Forms of application and semi-finished materials; lignocellulose; Mechanical properties; Plasticized starch; Polymer industry, paints, wood; starch products; Technology of polymers; thermal properties; Mechanical properties; Plasticized starch; Cellulose fibres; Composite; Cellulose; Fiber reinforced material; Lignocellulosics; Experimental study; Composite material; Thermal stability; Ester copolymer; Plasticizer; Dynamic mechanical properties; Natural fiber; Concentration effect; Oside polymer; Caprolactam copolymer; Adipate copolymer; Wheat starch; Polycaprolactone; Aliphatic copolymer
• ISSN: 0144-8617; 1879-1344
• DOI: 10.1016/j.carbpol.2003.11.015

The paper is focusses on the study of the thermal and mechanical behaviour of reinforced agro-materials. Various formulations based on plasticized starch matrix have been carried out, varying matrix formulation, filler content, fibres length and nature. Cellulose and lignocellulose fibres, which show unequal surface tensions, have been tested. After extrusion and injection moulding, the properties of these wheat starch-based biocomposites are analysed. Mechanical properties (tensile tests), thermo-mechanical properties (DMTA) and thermal degradation (TGA) are analysed. DMTA analysis shows important variations of main relaxation temperature, which can be linked both, to interactions resulting in a decrease of starch chain mobility and to a regular reinforcing effect. These results are consistent with the static mechanical behaviour, which vary according to the filler content (up to 30 wt%), fibre nature (cellulose vs. lignocellulose) and fibre length (from 60 μm to 1 mm). Besides, we have shown that the addition of cellulose fillers improves the thermal resistance of these biocomposites. Finally, we have tested the impact of the addition of biodegradable polyesters into these composites without significant effect on the post-processing stability.