Chopped basalt fibres: A new perspective in reinforcing poly(lactic acid) to produce injection moulded engineering composites from renewable and natural resources

Abstract

Abstract. This paper focuses on the reinforcing of Poly(lactic acid) with chopped basalt fibres by using silane treated and untreated basalt fibres. Composite materials with 5-10-15-20-30-40 wt% basalt fibre contents were prepared from silane sized basalt fibres using extrusion, and injection moulding, while composites with 5-10-15 wt% basalt fibre contents were also prepared by using untreated basalt fibres as control. The properties of the injection moulded composites were extensively examined by using quasi-static (tensile, three-point bending) and dynamic mechanical tests (notched and unnotched Charpy impact tests), dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), heat deflection temperature (HDT) analysis, dimensional stability test, as well as melt flow index (MFI) analysis and scanning electron microscopic (SEM) observations. It was found that silane treated chopped basalt fibres are much more effective in reinforcing Poly(lactic acid) than natural fibres; although basalt fibres are not biodegradable but they are still considered as natural (can be found in nature in the form of volcanic rocks) and biologically inert. It is demonstrated in this paper that by using basalt fibre reinforcement, a renewable and natural resource based composite can be produced by injection moulding with excellent mechanical properties suitable even for engineering applications. Finally it was shown that by using adequate drying of the materials, composites with higher mechanical properties can be achieved compared to literature data.

Thermal and mechanical analysis of injection moulded poly(lactic acid) filled with poly(ethylene glycol) and talc

“…Much research has been made to reinforce PLA with typically natural plant fibres [4][5][6][7][8][9][10][11][12][13] or even with glass [26] or basalt [27] fibres to make PLA based biocomposites suitable for high temperature engineering applications. By incorporating natural plant fibres to PLA in order to increase HDT it is critical to form strong connection between the fibres and the matrix.…”

Characterisation of natural fibre reinforced PLA foams prepared by supercritical CO2 assisted extrusion

“…The high degree of crystallinity is, however, crucial to obtain improved thermo-mechanical properties [24,25]. The prominent nucleating ability of basalt fibres has been utilized recently by Tábi et al [26] to obtain crystalline PLA composites of high heat deflection temperatures.…”

Injection molding of ceramic filled polypropylene: The effect of thermal conductivity and cooling rate on crystallinity

“…The degree of crystallinity (X) was determined from the exothermic and the endothermic peaks with Eq. (2), which takes into account the filler fraction of the compound [8,17].…”