JEC COMPOSITES MAGAZINE - Issue #39 - March/April 2008 - 42

FEATURE “Environment” Environment-friendly protein-/starch-based biodegradable polymers and composites Global warming, growing awareness of environmental and waste-management issues, dwindling fossil resources, and rising oil prices are some of the reasons why “bio” products are being promoted more and more for sustainable development. There are a number of applications (packaging, agriculture, household use, and more) where biodegradable polymers and composites are particularly suitable as sustainable alternatives. students) working on advanced polymer materials. The Centre’s objectives are: - meeting the needs of the polymer market and proposing innovative solutions that take into account all stages of a material’s life cycle; - formulating fibre-reinforced composites through the development of innovative fibre surface treatments and a new approach to interfacial mechanisms; - improving the ageing resistance of polymers and composites for temperature, UV exposure, moisture, etc. by developing specific in situ ageing tests and innovative approaches covering mechanical, chemical and physicochemical aspects. For about ten years now, the Centre has been involved in several different research programmes to develop innovative biodegradable polymers and composites from renewable resources and the corresponding characterisation systems. Its main investigations, for which the results are presented here, concern the development of biodegradable polymers from biomass, such as starch and proteins. In recent years, its research activities have focused more specifically on biopolymers derived from micro-organisms or biotechnologies, such as PLA and PHA. The Centre’s resources include polymer processing equipment for single- and twin-screw extrusion, 95T and 60T injection moulding, calendering, compression moulding, and more; grinding and sieving equipment; and methods to develop specific surface treatments for fibres and fillers. The Centre uses methods like FTIR analysis and calorimetric or thermo-gravimetric measurements to study, among others, the mechanical (static and dynamic tests), physico-chemical, and thermal properties of materials. It also uses accelerated ageing tests or a recently developed in situ ageing test called environmental stress cracking (ESC) to study the ageing resistance of polymers and composites, ANNE BERGERET, PROFESSOR ECOLES DES MINES D’ALÈS e now generate huge amounts of plastic waste, especially in the packaging industry and agriculture. Oil-based polymers are becoming more and more expensive, due to rising oil prices that are due in part to dwindling fossil resources. All this has sparked renewed interest in natural materials produced from renewable resources. The development of new materials now focuses on things like biodegradability properties and environmental safety aspects. W Biodegradable polymers obtained from renewable resources can be classified into three families: 1) agro-polymers like polysaccharides that are obtained by biomass fragmentation processes; 2) polymers like polylactic acid (PLA), that are produced by biomass fermentation processes; and 3) polymers obtained from conventional polymerisation of monomers extracted from biomass, like polyhydroxyalkanoate or PHA. There is also a fourth family of biodegradable polymers like polycaprolactones (PCL) or aliphatic and aromatic copolyesters, but these are obtained from non-renewable fossil resources. A wide range of such biopolymers is now commercially available, offering all sorts of properties that enable them to compete with nonbiodegradable polymers in several industrial sectors. Research activities at the Ales School of Mines The Ales School of Mines (Alès, France) is an engineering school under the tutelage of the Ministry of Industry. It includes three research centres, including the Materials Research Centre with about 20 people (excluding PhD JEC Composites Magazine / No39 March - April 2008
JEC COMPOSITES MAGAZINE - Issue #39 - March/April 2008

Table of Contents for the Digital Edition of JEC COMPOSITES MAGAZINE - Issue #39 - March/April 2008
