Basalt fiber reinforced and elastomer toughened polylactide composites: Mechanical properties, rheology, crystallization, and morphology

Abstract

A series of the reinforced and toughened polylactide (PLA) composites with different content of basalt fibers (BF) were prepared by twin screw extruder. The toughness of BF/PLA composites was improved further by the addition of polyoxyethylene grafted with maleic anhydride (POE-g-MAH), ethylene-propylene-diene rubber grafted with maleic anhydride (EPDM-g-MAH), and ethylene-acrylate-glycidyl methacrylate copolymer (EAGMA), relatively. The mechanical properties, rheology, crystallization, and morphology of BF/PLA composites were studied. The results showed that basalt fiber had significant reinforcing and toughening effect in comparsion with glass fiber. EAGMA was more effective in toughening BF/PLA composites than POE-g-MAH and EPDM-g-MAH. When the content of EAGMA achieved to 20 wt %, the impact strength of BF/PLA/EAGMA composite increased to 33.7 KJ/m 2 , meanwhile the value was improved by 71.1% compared with pure PLA. According to dynamic rheometer testing, the use of the three kinds of elastomers increased the melt dynamic viscosity. Differential scanning calorimetry analysis showed that POE-g-MAH and EPDM-g-MAH can decrease the cold crystallization temperature (T cc ) to approximately 20 C and dramatically improve crystallinity (v c ) of BF/PLA composites.

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

“…These results are again better compared to literature data (Liu et al [28]), where the surface of the basalt fibres were smooth and poorly wetted in spite of the reinforcing effect. Good quality wetting was achieved by Kurniawan et al [29] by using plasma treatment of the basalt fibres, however only basalt fibre reinforced PLA composites were produced with lower mechanical properties compared to our results.…”

“…The coefficients for the regression can be found in Table 2. The mechanical properties of the injection moulded composites are better compared to results from Liu et al [28] by 12, 25 and 53% according to tensile, flexural and Charpy impact strength respectively at same basalt fibre content (40 wt%) and also better compared to result from Kurniawan et al [29] by 24 and 143% according to tensile strength and tensile modulus at same basalt fibre content (25 wt% (note that 25 wt% basalt fibre content composite was not fabricated in this research, but due to the highly linear relationship, the properties were determined by interpolation)). The reason for the better properties can be found in the higher drying tem- perature of PLA prior to processing as it is published in our former research [31].…”

“…It was found that by increasing the plasma polymerisation time the tensile strength of the composites increased compared to PLA when the reaction time was higher than 3 minutes. Although the plasma polymerised fibres seem to be well wetted by the PLA, the tensile strength was lower compared to results from Liu et al [28]. Finally Chen et al [30] successfully produced PLA based scaffolds reinforced with basalt fibres.…”

“…The suitability of that sizing material in a wide temperature range was proven by DMA tests. Basalt fibres seem to be a good alternative to reinforce PLA, however, the number of papers in basalt fibre reinforced PLA is very limited [28][29][30]. Liu et al [28] demonstrated that basalt fibres with the adequate sizing can improve tensile, flexural and impact strength of PLA more significant as plant fibres.…”

“…Basalt fibres seem to be a good alternative to reinforce PLA, however, the number of papers in basalt fibre reinforced PLA is very limited [28][29][30]. Liu et al [28] demonstrated that basalt fibres with the adequate sizing can improve tensile, flexural and impact strength of PLA more significant as plant fibres. It was also found that by using 20 wt% of basalt fibres and 20 wt% of ethylene-acrylate-glycidyl methacrylate copolymer (EAGMA) the impact strength can be further increased up to 34 kJ/m 2 from the original value of PLA of 19 kJ/m 2 (unnotched Charpy test results).…”