Word: lignin
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Dates: during 1960-1969
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Pulp & Chlorine. To brominate wood pulp, Dr. Lewin simply adds sodium bromide, which is as stable as table salt, to the solution in a standard bleaching apparatus, then bubbles chlorine through it. The combination of chemicals releases active bromine in a form that attaches itself to the lignin in the pulp. Treating solid wood is a more complicated process, but the results are spectacular. When a piece of brominated wood is put in a hot fire, it does not burn. After a while, a layer of carbon forms on its surface, but carbonization stops as soon as the wood...
Bromine has long been known for its fireproofing qualities, but if it combines with wood's cellulose fibers, it weakens them seriously. Dr. Lewin's process gets around this disadvantage by forcing the bromine to attach itself to the wood's lignin, the cement that causes the fibers to stick to each other. The best grades of paper have no lignin, but the types of wood pulp used to make paperboard and wallboard retain enough of it to make Dr. Lewin's process useful...
...studies, Dr. Lewin does not yet know in detail how bromine fireproofing works, but in general the action is connected with the way that wood burns. When heat is applied to natural lignin and cellulose, they give off combustible gases that form flames and spread the fire by heating more wood. Somehow, bromine seems to make those gases nonflammable. And with no flames to spread it, combustion stops as soon as the external heat source, such as a lighted match, is removed...
...Free Traders. Still another potential profit area lies in silvichemicals, i.e., chemicals derived from wood. One big hope: turning lignin -the noncellulose element that constitutes 25% of a tree -into derivatives ranging from ersatz foam rubber to a substitute for carbon black in tires. Says West Virginia's research-minded Chairman David Luke: "The paper industry today generates some $12 billion in sales a year. If we took advantage of wood chemicals, we could double that- and the materials would be free." Because it forced them to seek new markets, the slump from which they are now emerging...