Southern pine chemical treatment

Other possibilities are a) surface tension, b) molecular size, c) chemical activity, d) solvency, and e) ability to swell wood. Some of these factors may be operative in treatments with propylene oxide which have been carried out by Rowell (33). In this study, he used a mixture of 95% propylene oxide and 5% triethyl-amine (v/v). He was able to completely treat southern pine and red pine heartwood, both of which were classified as being refractory. This work clearly shows that with the proper treating medium, heartwood can be fully penetrated. 

Southern pine with a dual treatment of chemical modification with butylene oxide or butyl isocyanate followed by lumen-fill treatment with methyl methacrylate, or southern pine impregnated with methyl methacrylate and polymerized in situ, resulted in modified woods that were resistant to accelerated weathering and to ultraviolet light alone. Physical, chemical, and microscopic changes occurring as a result of ultraviolet light irradiation are described. 

Table V. Changes in Volume of Southern Pine upon Drying and Chemical Treatment...

Table VI. Volume Changes in Southern Pine upon Chemical Treatment...

Sulfate turpentine is obtained as a by-product during the kraft pulping of pine woods. Vapors periodically released from the top of the digesters are condensed, and the oily turpentine layer is separated and purified by fractional distillation and treatment with chemicals to remove traces of sulfur compounds. Sulfate turpentine is very similar to gum turpentine obtained from the oleoresin of the tree and contains 60 to 70 percent a-pinene, 20 to 25 percent j8-pinene, and 6 to 12 percent other pinenes. Sulfate turpentine from western North America woods contains appreciable amounts of A -carene, which is used as a solvent. In the United States, about 80 percent of the annual production of turpentine is from the kraft pulping of southern pines (approximately 125 million liters). 

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