Effect of graft copolymerization on mechanical, thermal, and chemical properties of grewia optiva/unsaturated polyester biocomposites

Abstract

Present manuscript deals with surface modification of Grewia optiva fiber through graft copolymerization with acrylonitrile (AN). These surface modified cellulosic fibers were then used as reinforcement to prepare natural fiber reinforced unsaturated polyester matrix based biocomposites. Different reaction parameters for graft copolymerization were optimized to get the maximum graft yield (10.42%). The graft copolymers formed were characterized by FTIR, SEM, XRD, and TGA techniques. On grafting, thermal stability of fibers increased, which has been also supported by energy of activation (Ea) data obtained for both raw and grafted fiber. The grafted fibers were also subjected to evaluation of physicochemical properties. Subsequently, composites of unsaturated polyester matrix reinforced with different fiber loadings (0, 10, 20, 30, and 40% in terms of weight) of both raw and grafted fiber have been fabricated by hand lay up method. Mechanical properties of composites were studied and have been found to be higher when compared with polymer matrix. However, maximum enhancement in mechanical properties has been observed in case of grafted particle reinforced UPE composites in comparison to raw particulate reinforced composites. Further these composites were also subjected to SEM, DSC, and chemical resistance studies. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers

Studies on the Performance of Polyester Composites Reinforced with Functionalized Grewia optiva Short Fibers

“…Benzoyl chloride treatment of G. optiva fiber was carried out by using a 5 vol% benzoyl chloride in 10% alkali solution for 10–15 min as per the procedure reported earlier . Furthermore, graft copolymerization of G. optiva fibers with AN/AAc was carried out in a reaction flask at optimized time, temperature, initiator, nitric acid, and monomer concentration as per methods discussed earlier . The optimized parameters for graft copolymerization of fibers with AN and AAc were [CAN]: 1.82 × 10 −2 mol L −1 ; [HNO 3 ]: 2.88 × 10 −2 mol L −2 ; [AN]: 3.05 × 10 −1 mol L −1 ; time 150 min; temperature: 35°C and [CAN]: 1.82 × 10 −2 mol L −1 ; [HNO 3 ]: 2.88 × 10 −2 mol L −2 ; [AAc]: 3.50 × 10 −1 mol L −1 ; time: 120 min: temperature: 45°C, respectively.…”

Removal of Methylene Blue Dye from Wastewater Using Polydopamine Agave Americana Fibres-co-Poly(AAc)/Ag Nanocomposites

“…Further, upon grafting poly (AAc) onto AAFs-g-PDA, a large amount of AAc has been observed to be deposited on the fibre backbone, causing many morphological alterations in the fibre (Figure 4c). Also, after grafting with AAc, the fibre surface became more rough and uneven [41]. The roughness of fibres was further noticed to be enhanced after the deposition of spherical-polydisperse silver nanoparticles onto AAFs-g-PDA-poly (AAc) (Figure 4(d)).…”

The bright side of cellulosic hibiscus sabdariffa fibres: towards sustainable materials from the macro- to nano-scale

“…The inherent drawbacks of PFs, such as high moisture absorption, water swelling, degradation, poor chemical and fire resistance, high dispersion of mechanical properties and poor adhesion with thermosetting/thermoplastic or cementitious matrices, have limited their role in composite industries. [130][131][132] For this reason, efforts have been made by researchers to tailor the surface of PFs utilizing various techniques such as mercerization, silylation, benzoylation, cyano-ethylation, etherification, esterification and graft co-polymerization to meet the requirements for current challenging applications in the water treatment and polymer industries. 115,[133][134][135] Furthermore, researchers have also tried to control the surface characteristics of the different macro-HSFs; the results are summarized in Table 7 (Fig.…”