Toughness of Polyolefins Composites with Micro-fillers
Co-investigator: prof. RNDr. Zdeněk Knésl, CSc.
Number of Project: GA ČR 106/07/1284
Agency: Czech Science Foundation
Duration: 01. 01. 2007 - 31. 12. 2009
Purpose of adding fillers to polymers is primarily to increase the stiffness and to improve the dimension stability. Generally, the addition of mineral fillers has an embrittling effect and decreases fracture toughness. Most studies on modification of semi-crystalline polymers with rigid particles report a significant loss of toughness compared to the neat polymer. Principle of the project is to use the rigid particles of sub-micron size as toughening agent and to mimic the rubber toughening mechanism. The rigid particles can act in this way only under certain requirements concerning its size, aspect ratio, dispersity and the type of its deformation in
matrix. Toughening effect is studied on the various model structures including the influence of particles parameters, type of polymer matrix and the adhesion. These structures are examined from the structural as well as fracture point of view. Mathematical model based on finite element calculations is faced with experiments.
Publications:
Knésl, Z., Hutař, P., Náhlík, L., Nezbedová, E., Vlach, B., Role of particle size and filler matrix on stress state in thermoplastic composites, Computational modeling and experiment of composite materials, Liptovský Mikuláš, 2007