Carbohydrate Polymers 117 (2015) 11–18 Contents lists available at ScienceDirect Carbohydrate Polymers j ourna l ho me page: www.elsevier.com/locate/carbpol Graft copolymerization of ethyl acrylate onto tamarind kernel powder, and evaluation of its biodegradability Alicia del Real a , Daniela Wallander b , Alfredo Maciel b,∗ , Gerardo Cedillo b , Herminia Loza c a Departamento de Nanotecnología, Centro de Física Aplica y Tecnología Avanzada, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro C.P. 76230, Qro., Mexico b Instituto de Investigaciones en Materiales, Universidad Nacional Autónoma de México, 04510 Mexico DF, Mexico c Departamento de Bioquímica, Facultad de Química, Universidad Nacional Autónoma de México, Cd. Universitaria, 04510 México DF, Mexico a r t i c l e i n f o Article history: Received 24 June 2014 Received in revised form 27 August 2014 Accepted 8 September 2014 Available online 28 September 2014 Keywords: Biodegradable polymer Tamarind seed polysaccharide Poly(ethyl acrylate) Graft polymer a b s t r a c t In the present study, tamarind kernel powder and ethyl acrylate were reacted by free radical polymeriza- tion to synthesize a grafted copolymer soluble in water. The grafted copolymer was analyzed by Fourier transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR); FTIR showed a shift of the vibration of R CO OR ′ from 1258 cm -1 to 1253 cm -1 . This shift appeared because of the grafting copolymerization. Films were prepared to study the mechanical properties and the biodegradation of this material. The mechanical properties of the grafted copolymer were found to lie between those of the parent polymers, suitable for disposable products. The new grafted copolymer manifested a steady pro- cess of biodegradation under incubation with the bacterial strain Alicycliphilus sp. BQ1; this was proved by scanning electron microscopy (SEM) and near infrared spectroscopy (NIR). © 2014 Elsevier Ltd. All rights reserved. 1. Introduction The greater durability of synthetic polymeric materials com- pared to traditional, naturally-occurring materials causes serious environmental pollution due to discarded, undegraded polymers (Okada, 2002). In spite of recycling programs, most plastics still end up in municipal landfills, creating the problem of finding suitable landfill sites (Wu, 2012; Fang et al., 2005). Considerable effort has gone into developing biodegradable polymers that degrade more rapidly in the environment when discarded (Rutot, Duquese, Ydens, Degeé, & Dubois, 2001). One technique used is graft copolymeriza- tion of synthetic monomers to natural polymers. Copolymerization, as a modifying chemical reaction, has been used to transform the properties of natural raw materials (Princia et al., 2005; Mishra & Bajpai, 2005; Nishioka, Minami, & Kosai, 1983; Ghosh, Sen, Jha, & Pal, 2010). Indeed, graft copolymerization has become an important resource for developing advanced materi- als, as it can improve the functional properties of polysaccharides (Chang, Hao, & Duan, 2008; Da Silva, De Paula, & Feitosa, 2007; Geresha et al., 2004), and has generated a new industry interested ∗ Corresponding author. Tel.: +52 55 56224590; fax: +52 55 56161201. E-mail addresses: adelreal@unam.mx (A. del Real), anywallander@gmail.com (D. Wallander), macielal@unam.mx, macielalfredo@yahoo.co.uk (A. Maciel), gcedillo@iim.unam.mx (G. Cedillo), hlozat@gmail.com (H. Loza). in vanguard research in biopolymers to increase the use of agricul- tural materials and their by-products and so reduce consumption of unsustainable synthetic materials. Many agricultural products can be used in copolymers through blending with one or more additional materials. The main components of these biopolymers are storage and structural polysaccharides. Storage polysaccharides include starch and glyco- gen, whereas structural polysaccharides include cellulose, chitin and glucan (these polysaccharides differ in the types of linkages between the monomers; Flieger, Kantorova, Prell, & Rezanka, 2003). Natural polymers that are currently being investigated are cel- lulose, chitin, and agricultural products like starch, wheat and soybean proteins, and milk, among others. Starch and cellulosic fibers are the most commonly-used polysaccharides from renew- able resources (Kochumalayil, Sehaqui, Zhou, & Berglund, 2010). Polysaccharides are unique raw materials since they are the most abundant natural polymers, inexpensive, widely available in many countries, renewable, stable, hydrophilic, and modifiable (Abo-Shosha, Ibrahim, Allam, & El-Zairy, 2008). Because starch is produced by plants it is susceptible to biodegradation (Bogaert & Coszach, 2000). Lignin is another polymer that has been explored in the search to prepare a novel polymer blended with starch (Vengal & Srikumar, 2000). However, by using materials like starch, the polymer industry might come into competition with food indus- tries and cause problems in the future. Therefore, an alternative source of polysaccharides is required. http://dx.doi.org/10.1016/j.carbpol.2014.09.044 0144-8617/© 2014 Elsevier Ltd. All rights reserved.