Carbon fibers, lignin based

Griffith, W.L., Compere, A.L. and Leuten Jr., C.F. 2004. Lignin-Based Carbon Fiber for Transportation Applications. 2004 International SAMPE Technical Conference, pp. 227-235. 

In those days, the mechanisms of carbonization of polyvinyl chloride (PVC) were also under study in our laboratory. We found that PVC transformed to a beautiful lustrous pitch upon heating to 400°C under nitrogen. This PVC pitch could be spun quite easily, by comparison with molten lignin, and thus the pitch-based carbon fiber was first prepared in essentially the same way as the lignin-based carbon fiber. We recognize now that we were fortunate in first using PVC pitch. We later tried many other pitches as raw materials for carbon fiber, but PVC pitch was the only one that could be spun without any pretreatment. This was in 1963. We immediately applied for a patent (2 ), and the fundamentals of pitch preparation and spinning as well as the structure of the finished fibers were published in 1965 (3 ). 

In this entry, the effect of blending recyclable poly-(propylene) (PP) and poly(ethylene terephthalate) (PET) with lignin on carbon fiber production is presented. We discuss the effects of lignin structure and specific intermolecular interactions on lignin thermal properties as well as the effect of blend composition on surface morphology, mechanical properties, and the manufacturing process of lignin/recyclable plastic-based carbon fibers. 

Johnson, D.J. Tomizuka, I. Watanabe, O. Fine-structure of lignin-based carbon-fibers. Carbon 1975, 13 (4), 321-325. 

Braun, J. Holtman, K. Kadla, J.F. Lignin-based carbon fibers oxidative thermostabilization of kraft lignin. Carbon 2005, 43, 385-394. 

Methods for the isolation of lignin polymers, and for use of the isolated lignin polymers have been described (39). Lignin containing compositions can be used in carbon fiber composites, resins, adhesive binders and coatings, PLf-based foams, rubbers and elastomers, plastics, films, paints, nutritional supplements, food and beverage additives. Lignin polymers may be produced at low cost, and may... 

Kadla,)., Kubo, S., Venditti, R, Gilbert, R., Compere, A., and Griffith, W. (2002) Lignin-based carbon fibers for composite fiber applications. Carbon, 40 (15), 2913-2920. 

Lignin is part of the composition of natural polymers in variable proportions. The aromatic structure of the lignin can be used as source of several phenolic products, which may substitute petroleum-based compounds. Bio-based composites have gained prominence over the past two decades owing to both environmental concerns and waste disposal problems. Lignin-based biomaterials include carbon fibers, polymer modifiers, resin/adhesives/binders and others. 

Figure 7.6 Lignin-based carbon fibers prepared by electrospinning.

The porous structure and specific surface of activated carbons are determined by precursor type [13] and pyrolysis parameters, i.e. temperature [14] and heating rate jl5.16]. M y papers are dedicated to the synthesis of active carbons based on lignin-cellulose materials of various types [17]. There are empirical dependencies of texture on thermal treatment parameters for caibon materials from various precursors of plant nature [13,14,18]. Models for cellulose fibers pyrolysis are suggested [15). 

Panthapulakkal and Sain [10] reported better interfacial bonding between wheat straw fibers to HOPE compared to corncob and corn stalk fibers. They attributed this to more-lignin type and carbon rich hydrophobic surface of wheat straws compared to the other agro-based fillers. They observed higher percentage of silica on the wheat straw fiber surface than the other fibers. 

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