Surface modification of wood flour and its effect on the properties of PP/wood composites

Wood polypropylene composites prepared by thermally modified fibers at two extrusion speeds: mechanical and viscoelastic properties

“…It has good mechanical and thermal properties, and low density and low melting temperature (Son et al 2001;Premalal et al 2002;Yang et al 2004;Bledzki and Faruk 2005;Arbelaiz et al 2006;Ashori and Nourbakhsh 2010;Lee et al 2012). However, there is a phase incompatibility between the hydrophobic PP matrix (low surface energy) and the hydrophilic wood flour (high surface energy) (Maldas and Kokta 1993;Kazayawoko et al 1999;Dominkovics et al 2007), with weak interfacial adhesion between them. The strong fiber-fiber interactions, which are leading to agglomeration, limit the dispersion of the fibers in the matrix.…”

Thermally initiated solvent-free radical modification of beech (Fagus sylvatica) wood

“…There are three general approaches to wood modification: (1) lumen filling, (2) bulking treatments, and (3) grafting with covalent bond formation (Homan and Jorissen 2004). The chemical grafting of wood usually requires a solvent environment and numerous types of reagents and processes such as (1) urethanes using isocyanatealcohol monoadducts (Engonga et al 2000), (2) alkylation using alkyl chlorides (Prakash and Mahadevan 2008;Dominkovics et al 2007;McDonald and Ma 2010), and (3) esterification using vinyl esters (Jebrane and Sébe 2008). Unfortunately, there are some limitations to these procedures notably cost, energy demand from solvent evaporation, and environmental impacts that can impede their industrial applications.…”

Benzylation and Characterization of Cold Naoh/Urea Pre-Swelled Bamboo

“…Benzylation reactions occur between benzyl chloride and the hydroxyl groups of lignocelluloses, forming ether linkages attached to benzene rings, which makes lignocelluloses more compatible with non-polar matrices. Benzylation of lignocelluloses such as wood (Mohammadi-Rovshandeh 2003;Dominkovics et al 2007), sisal fiber (Ferreira et al 2003), bamboo fiber (Kushwaha and Kumar 2011), ramie fiber , oil palm empty fruit bunch , and olive residue (Djidjelli et al 2008), has been successfully performed. It was reported that the benzylated lignocellulosic product is a good resource for the preparation of composites as compared to the native lignocelluloses, which had poor interfacial interaction with hydrophobic polymer matrices and hence decreased the mechanical properties of the composites .…”