Methyl isocyanate-treated Southern

Figure 3. Infrared spectra of methyl isocyanate-modified southern pine. Key A, unreacted wood (control) B, 17.7 WPG C, 47.2 WPG D, holocellulose from sample treated to 17.7 WPG E, lignin from sample treated to 47.2 WPG.

Additional evidence that bonding has occurred in the cell wall of methyl isocyanate-modified southern pine can be seen by considering the volume increase in the treated wood and comparing that to the theoretical volume of chemical added after thorough leaching of the treated wood. If the chemical has entered the wood cell wall, the increase in wood volume as a result of modification should be proportional to the volume of chemical added. 

Figure 5. Scanning electron micrographs of radially-split southern pine showing swelling of wood treated with methyl isocyanate. Key A, untreated control (245)0 B, 16.0 WPG (224X) C, 32.2 WPG (224X) D, 36.9 WPG (224x) E, 47.4 WPG (224X) F, 72.3 WPG (196X)-...

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