Title: The effect of plasma treatment of polyethylene powder on the mechanical properties of composites prepared by rotational molding

Abstract

Rotational molding, as well as 3D printing technologies, is based on sintering of raw materials under the ambient conditions. No additive pressure can be added to form a good adhesion between the matrix and the filler. Due to these conditions, the mechanical anchoring of the matrix to the filler that dominates the injection molding is not the case, and the formation of chemical bonding is necessary for good wetting and strong adhesion. Cold plasma surface treatment has been established as an effective and low-cost technology for surface hydrophilization of polymer materials without altering properties of bulk material. In our research untreated polyethylene (PE) and plasma modified polyethylene (PPE) as a matrix for composites produced by rotational molding has been studied as a model for non-pressure technologies Short glass fibers at different percentage were manually mixed with untreated and treated linear low density polyethylene powder and used to prepare a samples using laboratory scale rotational moulding machine. A new approach of using polyethylene waxes as a sizing agent was introduced. The scanning electron microscopic images showed that the addition of plasma treated polyethylene waxes improved the adhesion between the glass fibres and plasma treated polyethylene. Mechanical tests also showed an improvement in tensile and flexural modulus of the composites prepared by treated materials.