Composites grafted cellulose reinforcement

In order to develop composites with better mechanical properties and environmental performance, it becomes necessary to increase the hydrophobicity of the biofibers and to improve the interface between matrix and biofibers. Graft copolymerization of biofibers is one of the best methods to attain these improvements. As of now, only few studies have reported the use of biofiber graft copolymers as reinforcing material in the preparation of composites [33], Mechanical properties of thermoplastic composites reinforced with acrylate-gro/led henequen cellulose fibers were studied. It has been found that best results could be obtained with poly(methyl methacrylate) (PMMA)-grafted cellulose fibers because of better fiber-matrix adhesion. The modulus of poly(vinyl chloride) (PVC) composites is increased when grafted or ungrafted cellulose are used as reinforcement but the composites with... 

S. Kalia, "Development of polymer matrix based composites using grafted Flax cellulose as reinforcing agent and evaluation of some mechanical and chemical properties" Ph.D. Thesis, Punjab Technical University, Jalandhar, Punjab, 2008. 

The thermal behavior of the composites based on raw and surface modified Grewia optiva particle fibres reinforced unsaturated polyester matrix was studied [47]. The fibres were modified by mercerization, silanation, benzoylation and graft copolymerization. The thermal stability of the composites containing modified fibres was improved compared to the unsaturated polyester matrix and to the composites containing untreated fibres. This was a consequence of the additional intermolecular bonding between fibres and matrix induced by the surface modification. The highest thermal stability was obtained by the composites based on silanated fibres due to the formation of strong covalent bonds between silanes and cellulose. 

The most recent significant development in the market place has been the very strong growth in the use of cellulose fiber reinforced composites, especially those based on wood fiber and powder. Coupling agents are often used in these formulations, especially to reduce water absorption and accompanying loss of properties. Maleic anhydride grafted polyolefins have been found to be very suitable additives for this purpose, and this has led to a marked increase in their use. 

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