Other

Rauma Repola Oy

Jarl Johan Lindberg

Johannes Turunen

Matti Dolk

Vaino Era

Bo Hortling

Method for manufacturing polyurethane films and surface coatings from tall oil pitch. Tall oil pitch with an acid number of about 30-60 and a hydroxyl number of about 60-90 is esterified by adding about 5-15 weight fractions of an aliphatic alcohol comprising at least three OH-groups and about 0.1-0.5 weight fractions preferably p-toluenesulphonic acid per 100 weight fractions tall oil pitch, and by heat treatment at a lowered pressure until the acid number of the mixture is about 5-35 and the hydroxyl number is about 200-350. Aliphatic triisocyanate preferably dissolved in an inert organic solvent is added to the tall oil pitch ester thus attained in an amount such that the amount of isocyanate groups is 10-35 weight fractions per 100 weight fractions tall oil pitch ester. To the mixture thus attained is added known dilution agents and additives; the mixture is spread on a base material in a known way and the film or surface coating is finally polymerized at room temperature or at higher temperatures.

Method for manufacturing polyurethane films and surface coatings from

This invention relates to a three-dimensional, aromatic, sulfur-containing polymer based on lignin. The polymer is characterized in that it is amorphous, practically insoluble in water and conventional organic solvents; it contains thioether bonds and possibly sulfoxide and/or sulfone groups formed by oxidizing of thioether bonds, and possibly carbon-carbon bonds between aromatic rings and/or side chains and possibly other bonds typical to lignin, depending on reaction conditions. Its thermostability is at least 200.degree. C.; and it has been obtained from lignin which is dissolved or undissolved, chlorinated or unchlorinated, purified or containing other components of spent pulp liquor, by heating at about 160.degree.-350.degree. C., preferably in an atmosphere substantially of nitrogen and/or water vapor, for a time sufficient to form the polymer, with sulfur and/or inorganic or organic sulfur compounds so that degradation products of lignin, containing aromatic rings, or corresponding aromatic compounds, with an activating substituent have possibly been added.

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Helsinki, Finland

Jarl Johan Lindberg