Performance Properties of Irradiated Recycled Polypropylene as a Compatibilizer in Recycled Polypropylene/Microcrystalline Cellulose Composites

Abstract

Effects of irradiated rPP compatibilizer, on the mechanical and thermal properties of recycled polypropylene/microcrystalline cellulose composites (rPP/MCC), are investigated. rPP is irradiated with an electron beam at dosages ranging from 10, 20, 30 to 50kGy. A matrix, containing of unirradiated and irradiated rPP (50:50 by ratio), is then added to 5, 20 and 40wt% MCC fibres. The composites are prepared using a twin screw extruder, followed by injection moulding. The properties are then characterized using tensile and thermal degradation tests. The improvement of Young’s modulus by up to about 45% suggests a compatibilising effect of the irradiated rPP. Fracture surface observations reveal an adhesion between rPP matrix and MCC fibres. However, the thermal stability deteriorated with the addition of MCC and irradiated rPP.

Dynamic Mechanical And Water Absorption Properties Of Microcrystalline Cellulose Reinforced Polypropylene Composites: The Effect Of Unconventional Irradiation Route

“…Upon further analysis, it was observed that there had been a greater increase of the E' of the rPP:i-rPP/MCC composites as compared to the neat rPP. This implies that the addition of MCC fibers had enhanced the stiffness by restricting the flow of rPP matrix, which is in line with the results obtained from Young's modulus [3][4]. The storage moduli at specific temperatures; -50 °C (glassy region), +27 °C (room temperature) and +100 °C (possible use temperature) were selected as a means of comparing the effect of rPP:i-rPP ratio and irradiation dose.…”

“…Therefore, the present work aims to further investigate the effects of irradiated recycled PP on dynamic mechanical analysis (DMA) and water absorption properties from the developed composites. The results derived from this analysis is a supplementary research on an earlier study conducted by Lazim et al [2][3] and Samat et al [4].…”

“…During the irradiation process, the energy is transferred from the irradiating source to the atoms of irradiated materials. This will result in a few chemical reactions taking place, such as chain scission, branching, and crosslinking [1][2] that subsequently alter the mechanical and thermal properties of the materials [2][3][4][5][6][7]. Generally, the formation of crosslinking will lead to improvements of properties.…”

“…Tensile tests were performed in both cases to evaluate the function of irradiated PPs as a compatibilizer. This unconventional irradiation route had also been further explored in our previous works [2][3][4][5] in recycled polypropylene (rPP) that was reinforced with microcrystalline cellulose (MCC). Here, the possibility of irradiated recycled PP being a compatibilizer was assessed based on the tensile, impact strength and thermal properties.…”

“…Here, the possibility of irradiated recycled PP being a compatibilizer was assessed based on the tensile, impact strength and thermal properties. In all of these cases [2][3][4][5][15][16], the properties of composites had been better than the controlled polymer, thereby proving the compatibility effect of the virgin PP or recycled PP through the use of IR.…”