Functionalizing Lignin Matrix Composites

Development of ARBOFORM started in the late 1990s, the material being composed only of the components lignin, reinforcing natural fibres and some natural additives. The material 

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Lignin is synthesised in plants from monomeric molecnles, whose functionality varies from two to four. Thus, both branched chain and the crosslinked structure may be formed. In plant tissue, the polymer chains of lignin are snrronnded by macromolecules of noncellulosic polysaccharides, with which they form an amorphous lignocarbohydrate matrix. The experimental methods that allow the stndy of the complex topology of macromolecules in a multicomponent solid composite are very limited. Therefore, most of the data are interpreted using theoretical methods developed from polymer chemistry. 

The anhydride functionality in the compatibilization research described before may react with the lignocellulosic, but there is no evidence to support that at this time. A higher level of grafted anhydride on the polypropylene would be required for the alloy reactions, and it would be expected that the reaction between grafted thermoplastic and jute or kenaf would take place both on the matrix polymers (lignin and hemicelluloses) and in the cellulose backbone. Some decrystallization of the cellulose may be desired to give more thermoplastic character to the entire composite. 

With cells and tissues in suspension culture, the matrix of deposited materials extracellular to the cell wall often stains for lignin and contains tannins and glycoproteins of yet undefined composition (82). This material binds with synthetic growth regulators introduced into the medium. The chemical nature of these extraneous materials is a strong function of the tissue or cell explant source and of the conditions of culture (40). 

Ago et al. prepared bifibrous mats by electrospinning mixtures of biodegradable polymers lignin and PLA with CNs. Fiber morphology and thermal stability were smd-ied as a function of filler concentration. Strong interaction between the fignin-PLA matrix and the CNs led to improved thermal stability of the membranes. Electrospun nanofibrous composites that use cellulosic fillers have tremendous potential for the development of novel multifunctional materials [67]. 

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