Maleic anhydride grafted linear low density polyethylene/waste paper powder composites with superior mechanical behavior Arun Saini, Chandravati Yadav, Madhab Bera, Pragya Gupta, Pradip K. Maji Department of Polymer and Process Engineering, Indian Institute of Technology Roorkee, Saharanpur Campus, Saharanpur, Uttar Pradesh 247001, India Correspondence to: P. K. Maji (E - mail: pradip.fpt@iitr.ac.in) ABSTRACT: The present work aims to study the perspectives of an efficient utilization of waste products as fillers for the thermoplastic polymer. Maleic anhydride grafted linear low-density polyethylene (LLDPE-g-MA), without any compatibilizers, has been used as polymer matrix to prepare composites with different contents (0–50 phr) of waste paper powder (WPP). Mechanical properties assessment has shown up to 88% improvement in tensile strength and a huge increment of 409% in Young’s modulus for the compo- sites prepared at 30 phr WPP. The reinforcement effect of WPP in the polymer matrix was also assessed by Guth-Gold and modified Guth-Gold equations. Microstructural analysis of the fractured surfaces revealed good interfacial adhesion with fewer voids and fiber pull out up to 30 phr WPP loading. Interfacial interaction between maleic anhydride group of LLDPE-g-MA and AOH groups pre- sent dominantly in the cellulosic component of WPP was established through Fourier transform infrared spectroscopy (FTIR). The thermal properties of prepared composites were analyzed by DSC (differential scanning calorimetry). V C 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45167. KEYWORDS: composites; mechanical properties; polyolefins; structure-property relationships; thermal properties Received 9 January 2017; accepted 29 March 2017 DOI: 10.1002/app.45167 INTRODUCTION The active utilization of waste materials for producing economic and efficient products is one of the supreme research areas worldwide. 1 In the quest of regulating the waste management and sustainability, production of polymer composites with the inclusion of various waste materials as filler is conceptually a modest and often cost-effective tactics. The strategic usage of waste materials for preparing new polymeric composite materi- als can reduce the amount of actual polymer usage and hence can be a logical step towards the reduction of plastic waste. 2–5 Importantly, the use of greener waste feedstock such as cellulose rich materials has engrossed much awareness due to social development factors and new government policies. 5 The paper is one such waste material that is most widely used, abundant, biodegradable and ecofriendly. Every year, a huge amount of around 2.75 million tons postconsumer waste paper is collected in India from various industries and households sources. 6 These waste papers are environmental-friendly, practi- cally sustainable and low-cost post-consumer products. They largely contain organic lignocellulosic fibres (mostly cellulose- rich fibres, 70–100%), little amount of inorganic fillers such as calcium carbonate, clay, titanium oxide etc. (0–30%) and print- ing inks. 7,8 Cellulose is a classical example of most copious biogenic materials that offers a great perspective for the devel- opment of high-end application products with remarkable properties of being eco-friendly, renewable, biodegradable and biocompatible. 9 It is a long chain, linear homopolymer with a syndiotactic configuration. Its chemical structure is composed of anhydro-b-D-glucopyranose units linked together with b- (1!4) glycosidic linkage where oxygen is covalently linked to C1 of one glucose ring and C4 of the adjoining ring. The molecular chains of cellulose are laterally stabilized through strong inter- and intramolecular hydrogen bonds as well as van der Waals forces. 9,10 The b configuration in cellulose, with all functional groups in equatorial positions, make it a good fibre- forming polymer where the molecular chain of cellulose extends in a more or less straight line. The –OH groups protrude later- ally along the extended cellulose molecule and are readily avail- able for H-bonding due to the equatorial positions of the hydroxyls in the cellulose chain. These extensive H-bonds cause the cellulose chains to assemble together in a highly ordered/ crystalline structure. 11 The promise behind cellulose-derived composites lies in the superior axial Young’s modulus of basic Additional Supporting Information may be found in the online version of this article. V C 2017 Wiley Periodicals, Inc. WWW.MATERIALSVIEWS.COM J. APPL. POLYM. SCI. 2017, DOI: 10.1002/APP.45167 45167 (1 of 9)