An Experimental Study on the Properties of Recycled High-Density Polyethylene

Abstract Recycling of plastic materials has become more environmentally important than recycling of other materials. The most important problem during recycling is the presence of oil, dirt, dust and metal particles that are mixed with plastic materials. These mixtures can change their its mechanical and physical properties and it is quite costly to remove them completely. Removing iron alloy particles from plastic is possible by using the magnetic method. However, removing non-metallic materials requires extra processing. In this study, the use of recycled High-Density Polyethylene (rHDPE) without an expensive cleaning processes has been investigated. Different amounts of aluminium oxide (Al2O3) were added to High Density Polyethylene (HDPE) to simulate the effect of non-metallic material involved. The effect of these contamination rates on the mechanical and physical properties of HDPE was examined in detail. For this purpose, recyclable materials were produced by mixing rHDPE with 1%, to 7% Al2O3 . The results show that up to 7% of the mixture has acceptable effects on the properties of HDPE. When the results of the experiments are examined, it is observed that there is a 3.74% change in the elastic modulus of the material. This means, that up to 7% non-metal contaminated rHDPE material can be used without any costly recycling process.

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High Density Polyethylene (HDPE) composite mixed with Azadirachta excelsa (Sentang) tree waste flour: Mechanical and physical properties

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/951/1/012045 ◽

2022 ◽

Vol 951 (1) ◽

pp. 012045

Author(s):

A M Zakaria ◽

M A Jamaludin ◽

M N Zakaria ◽

R Hassan ◽

S A Bahari

Keyword(s):

Physical Properties ◽

High Density Polyethylene ◽

Flexural Modulus ◽

Filler Loading ◽

High Density ◽

Injection Molding Process ◽

Molding Process ◽

Significant Difference ◽

Mechanical And Physical Properties ◽

Composite Samples

Abstract This article presents the application of plantation waste materials (leaves, branches and trunks) of Azadirachta excelsa (Sentang) tree in order to evaluate and compare their suitability as reinforcement and filler for high density polyethylene (HDPE) thermoplastics. The aim of the study was to investigate the effect of different types of Azadirachta excelsa (Sentang) trunks flour, branches flour and leaves flour fillers on the mechanical and physical properties of HDPE composite. The composite samples were produced using 25%, 35% and 45% by weight of flour filler loading and 2% coupling agent (maleic anhydride) using a twin-screw extruder, followed by injection molding process. The flexural modulus and tensile strength of the composite filled with trunk flour were not significantly different with the composite-filled branch flour. However, there is a significant difference between composite-filled leaf flour when compared to both composite-filled trunk flour and composite-filled branch flours. Overall, composite samples with trunk flour show better mechanical properties, while composite samples with lower filler loadings of 25% exhibit better dimensional stability compared to the other such as 35% and 45% filler loadings. The study also indicated that composite filled with leaf, branch and trunk flours had better mechanical strength than virgin HDPE.

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