POLYMER TESTING Polymer Testing 27 (2008) 93–99 Material Properties Processing and properties of polypropylene-latex modified waste tyre dust blends (PP/WTD ML ) M. Awang, H. Ismail à , M.A. Hazizan School of Materials and Mineral Resources Engineering, Universiti Sains Malaysia, Nibong Tebal, 14300 Penang, Malaysia Received 30 July 2007; accepted 12 September 2007 Abstract Attention has been focused on the preparation of latex modified waste tyre dust (WTD ML ) and its effect on tensile properties, swelling resistance and morphology as well as thermal properties of polypropylene (PP)-based blends. It is apparent that tensile properties of polypropylene-latex modified waste tyre dust (PP/WTD ML ) blends were better than those of polypropylene-unmodified waste tyre dust (PP/WTD UM ) blends. The presence of WTD ML enhanced the swelling resistance of the PP/WTD ML blends, indicating an improvement in PP-WTD ML interfacial adhesion. An improved dispersion as well as a size reduction of WTD ML was observed in the micrographs of tensile fracture surfaces. The embedded and encapsulated WTD ML elucidates the improved PP-WTD ML interaction. Moreover, the use of WTD ML did not show any diminution of the blend’s thermal properties. r 2007 Elsevier Ltd. All rights reserved. Keywords: Polypropylene; Modified waste tyre dust; Latex; Blend; Properties 1. Introduction Tyres have not only rendered some comfort to our daily undertakings but also represent a huge challenge to the sustainability of the environment. As their scrap constitutes the largest volume of waste rubber and does not degrade easily, their continuing accumulation all over the world has attracted a serious concern over the danger or damage incurred to public health as well as to the environment. Considering the economic and environmental advantages, recycling is one of the best options to choose. A number of possible applications of various forms of waste rubber in broad disciplines have been studied and reported [1–3]. Reuse of rubber from scrap tyres in formulating new reusable materials as well as attempts to improve waste rubber have been studied [4–6]. One of the most investigated thermoplastics for the use of scrap tyre rubber in polymer blends is polypropylene (PP) [7–9]. This is mainly due to its low cost, processa- bility and good balance of properties [10]. The authors have also recently investigated the effects of waste tyre dust (WTD) size and partial replacement of PP by WTD on the properties of PP/WTD blends [11] as well as the influence of trans-polyoctylene rubber (TOR) and dynamic vulcanization on the PP/WTD blend properties [12]. However, so far hardly any work is reported involving the modifica- tion of WTD using natural rubber latex, vulcanizing agent and blending with thermoplastics. ARTICLE IN PRESS www.elsevier.com/locate/polytest 0142-9418/$ - see front matter r 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.polymertesting.2007.09.008 à Corresponding author. Fax: +60 604 594 1011. E-mail address: hanafi@eng.usm.my (H. Ismail).