| 摘要 |
<p>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 DEG 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 DEG -350 DEG 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.</p> |
