Polyester-based biocomposites reinforced with wool fibers

In this work biocomposites based on a biodegradable polyester containing different amounts of wool fibers (up to 60 wt%) were prepared by melt blending in an internal batch mixer. Wool fibers were used as received, oxidized or pre-treated either with ethylene glycol or poly(vinyl alcohol) in order to preserve a high aspect ratio and increase adhesion with polymer matrix. Morphological, thermal, mechanical and dynamic-mechanical properties of the ensuing composites were investigated focusing the attention on fiber length and their distribution, fiber/matrix interaction, and, consequently, polymer reinforcement. Data obtained from mechanical and dynamic-mechanical investigations were also compared with theoretical models in order to obtain more information on arrangement and dimension of fibers, quality of composites as well as degree of adhesion between fiber and polyester matrix.