Lignocellulosic fibers modification

Rowell, R.M., Cleary, B.A., Rowell, J.S., Clemons, C. and Young, R.A. (1993b). Results of chemical modification of lignocellulosic fibers for use in composites. In Wood Fiber/Polymer Composites Fundamental Concepts, Processes, and Material Options, Wolcott, M.P. (Ed.). Eorest Products Society, Madison, Wiseconsin, USA, pp. 121-127. 

Chemical Modification of Lignocellulosic Fibers To Produce High-Performance Composites... 

Hon, D. N.-S. "Modification of Lignocellulosic Fibers." Paper presented at the Second Chemical Congress of the North Americal Continent, San Francisco, CA., Aug., 24-29, 1980, Abstracts of Papers, Part 1, cell-39. 

Zanini S et al (2005) Modifications of lignocellulosic fibers by Ar plasma treatments in comparison with biological treatments. Surf Coat Technol 200(1 ) 556-560... 

The effect of flax fiber modification and the effect on the presence of TCL were also studied by Arbelaiz et al. [17]. In his studies, fibers were subjected to maleic anhydride, vinyltrimetoxy silane, and aUcali with addition of MAPP-grafted polypropylene. All applied modifications produced improvement in the thermal stability of lignocellulosic material. Analysis of the crystalline structure showed the increase of crystallinity as a result of fiUer addition. Nucleation density around unmodified fibers was higher than around fibers modified with maleic anhydride. Surfaces of unmodified fibers had the surface active for initialization of transcrystaUization, which, in the case of modified fibers, did not occur. Son et al. [32] explained this phenomenon as... 

Various treatment methods onto oil palm fibers are already discussed in detail [22, 23, 45-47] including a detailed discussion on various treatments on lignocellulosic fibers in general to improve their properties [48]. Reviews on the developments in chemical modification and characterization of natural fiber-reinforced composites... 

MODIFICATIONS OF LIGNOCELLULOSE FIBERS AND ITS APPLICATION IN ADSORPTION OF HEAVY METALS FROM AQUEOUS SOLUTION... 

From Figures 15.13 and 15.14, it has been observed that fiber surface modification also affects the dielectric loss and dissipation factor of resulted UPE matrix-based biocomposites. Furthermore, the mercerized fibers-reinforced polymer composites have been found to have low dielectric loss and dissipation factor followed by raw fibers-reinforced UPE matrix-based composites. It may be due to the incorporation of—COC Hj onto lignocellulosic fibers and partial removal of cellulose chain and surface impurities from fibers surface after surface modification. However, the exact explanation for the above behavior is somewhat difficult as dielectric loss or dissipation factor also depends on fiber orientation [ 16]. Since fibers were inserted in the composite materials in statistical random orientation manner, there may be... 

Lignocellulosic research today is poised on the threshold of a new era of research breakthroughs. It has enabled the use of a wide variety of lignocellulosic materials, low-quality wood species and sawdust, and low-value lignin products. Lignocellulosic and cellulosic research efforts are under way to produce novel products for construction, transportation, plastics, fiber, packaging, and medical applications. Some of the major activities in chemical modifications of wood, cellulose, and lignins are the main features of this book. 

Chemical modification reactions continue to play a dominant role in improving the overall utilization of lignocellulosic materials [1,2]. The nature of modification may vary from mild pretreatment of wood with alkali or sulfite as used in the production of mechanical pulp fibers [3] to a variety of etherification, esterification, or copolymerization processes applied in the preparation of wood- [4], cellulose- [5] or lignin- [6] based materials. Since the modification of wood polymers is generally conducted in a heterogeneous system, the apparent reactivity would be influenced by both the chemical and the physical nature of the substrate as well as of the reactant molecules involved. 

Young RA (1996) Utilization of natural fibers characterizatiplastics composites. UNESP, Sao Paulo Zuchowska D (2000) Polimery kraistrukcyjne. Wydawnictwo Naukowo - Techniczne. Warszawa... 

Studies on acetylation as one of the methods for modification of lignocellulosic materials are conducted at our research center [7-9, 30, 33, 79-81]. Tables 10.1 and 10.2 show the values of strength of composites based on polypropylene matrix and long flax or hemp fibers. These components were obtained by compression molding according to a procedure described in a patent [82]. The developed method... 

Many factors such as adhesion between components, fiber topography, and kinetic parameters of crystallization of semicrystalline matrix have been reported to influence transciystallinity. The transcrystallinity phenomenon in the natural fibers/polypropylene system is affected by the different type of chemical treatment of lignocellulosic materials. Moreover, the ability of natural filler to induce nucleation in polypropylene matrix is also dependent on the kind of chemical modification of surface fibers. Predominant nucleation ability was found for unmodified fibers. However, chemical modification of fiber surface slightly depressed the nucleation of polypropylene matrixes. 

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