Lignin-based epoxy resins

In a recent addition to the elaboration of lignin-based epoxy resins, calcium LS was treated with epichloridrin to introduce oxirane functions in their structure [59]. Thereafter, these modified lignins were treated with maleic anhydride and the curing reaction leading to these novel epoxy resins was followed by FTIR spectroscopy [60]. More attention was devoted in this work to the kinetics and mechanism of the network formation than to any characterization of the properties of the ensuing materials, but this will probably be followed up. 

Hofmann K, Glasser WG (1993) Engineering plastics from lignin. 22. Cure of Ugnin-based epoxy resins. J Adhes 40 229-241... 

Lignin is a potential substitute for oil-based phenols in phenolic and epoxy resins and adhesives [208, 209]. Incorporation of lignin into polymer matrix (polyolefin) offers certain benefits including improved chemical and/or physical properties, UV stabilization, and enhanced biodegradation capacity [209-212]. 

Glasser and co-workers have contributed most significantly to the formulation of two families of lignin-based materials, namely polyurethanes and epoxy resins, in which lignin was modified in order to enhance its reactivity... 

LS is obtained as a by-product of sulfite pulping process. LS has not been used as a chemical component of common lignin-based polymers such as epoxy resins due to its ionic nature. LS is soluble in water and, at the same time, it is soluble in some kinds of solvent such as ethylene glycol, DEG, TEG, and PEG. [157]. LS-based PU foams can be prepared from LS-based polyols, LSD derived from DEG, LST from TEG, and LSP from PEG. The thermal and mechanical properties of rigid PU foams... 

Hirose S, Kobayashi M, Kimiira H, Hattikeyama H (2001) Synthesis of lignin-based polyester-epoxy resins. In Keimedy JF, Phillips GO, Williams PA, Hatakeyama H (eds) Recent advances in environmentally compatible polymers. Woodhead, Cambridge, pp 73-78... 

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