title: Vegetable fibres from agricultural residues as thermo-mechanical reinforcement in recycled polypropylene-based green foams.
abstract: Novel lightweight composite foams based on recycled polypropylene reinforced with cellulosic fibres obtained from agricultural residues were prepared and characterized. These composites, initially prepared by melt-mixing recycled polypropylene with variable fibre concentrations (10-25 wt.%), were foamed by high-pressure CO(2) dissolution, a clean process which avoids the use of chemical blowing agents. With the aim of studying the influence of the fibre characteristics on the resultant foams, two chemical treatments were applied to the barley straw in order to increase the α-cellulose content of the fibres. The chemical composition, morphology and thermal stability of the fibres and composites were analyzed. Results indicate that fibre chemical treatment and later foaming of the composites resulted in foams with characteristic closed-cell microcellular structures, their specific storage modulus significantly increasing due to the higher stiffness of the fibres. The addition of the fibres also resulted in an increase in the glass transition temperature of PP in both the solid composites and more significantly in the foams.
authors: Department of Textile and Paper Engineering, Universitat Politècnica de Catalunya, C/Colom 11, E-08222 Terrassa, Barcelona, Spain. Monica.ardanuy@upc.edu
authors: Mònica
authors: M
authors: Ardanuy
authors: Marcelo
authors: M
authors: Antunes
authors: José Ignacio
authors: JI
authors: Velasco
mesh_terms: D002482:Cellulose / Q000737:chemistry*; D005898:Glass / Q000737:chemistry; D001467:Hordeum / Q000737:chemistry; D011126:Polypropylenes / Q000737:chemistry*; D059027:Recycling / Q000379:methods*; D044366:Transition Temperature
chemical_list: D011126:Polypropylenes; D002482:Cellulose