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Lignin, obtained through steam explosion\ud from straw, was completely characterized via elemental\ud analysis, gel permeation chromatography, ultraviolet and\ud infrared spectroscopy, and 13C and 1H nuclear magnetic\ud resonance spectrometry. Polyurethanes were obtained by\ud treating steam-exploded lignin from straw with 4,4-methylenebis(\ud phenylisocyanate), 4,4-methylenebis(phenylisocyanate)\ud –ethandiol, and poly(1,4-butandiol)tolylene-2,4-diisocyanate\ud terminated. The obtained materials were characterized\ud by using gel permeation chromatography, infrared\ud spectroscopy, and scanning electron microscopy. Differential\ud scanning calorimetry analysis showed a Tg at 6°C,\ud assigned to the glass transition of the poly(1,4-butandiol) chains. The presence of ethylene glycol reduced the yields of\ud the polyurethanes. The use of the prepolymer gave the best\ud results in polyurethane formation. Steam-exploded lignin\ud was used as the starting material in the synthesis of polyesters.\ud Lignin was treated with dodecanoyl dichloride. The\ud products were characterized by using gel permeation chromatography,\ud infrared spectroscopy, 13C and 1H nuclear\ud magnetic resonance spectrometry, and scanning electron microscopy

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