Lignin

Description

An natural aromatic polymer found in the cell walls of grasses and woody plants. Lignin and Hemicellulose cement the fiber cells together. Lignin composes 17-30% of wood and thus Mechanical wood pulp also contains lignin. In the manufacture of paper pulp by chemical processes, lignin is removed by reaction with alkaline or sulfur compounds. The presence of lignin in paper shortens its overall lifetime as lignin can photo-oxidize to form acidic products which can then attack the cellulose. The lignin produced as a waste-product in the manufacture of paper is used in phenolic plastic products as a stabilizer, binder, dye dispersant, and filler. It is also a source of vanillin. In the destructive distillation of wood, lignin decomposes to produce methanol.

Synonyms and Related Terms

lignine (Fr.)

Other Properties

Insoluble in water and most solvents.

Composition	C41H32O6
Melting Point	250-275

Lignin will stain yellow when treated with Graff "C" stain. This stain is often used to determine the presence of lignin in paper samples and for paper fiber identification.

Authority

• Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976

• Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997

• John S. Mills, Raymond White, The Organic Chemistry of Museum Objects, Butterworth Heineman, London, 2nd ed., 1994

• The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998

• G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 450

• Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993

• The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 5510

• Walter C. McCrone, John Gustave Delly, The Particle Atlas, W. McCrone Associates, Chicago, IV, 1972

• Hoechst Celanese Corporation, Dictionary of Fiber & Textile Technology (older version called Man-made Fiber and Textile Dictionary, 1965), Hoechst Celanese Corporation, Charlotte NC, 1990

• Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982

• Mary-Lou Florian, Dale Paul Kronkright, Ruth E. Norton, The Conservation of Artifacts Made from Plant Materials, The Getty Conservation Institute, Los Angeles, 1990

• Rosalie Rosso King, Textile Identification, Conservation, and Preservation, Noyes Publications, Park Ridge, NJ, 1985

• Silvie Turner, Which Paper?, Design Press, New York, 1991

• Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000

• Website address 1 Comment: Archival Suppliers Glossary at http://www.archivalsuppliers.com/glossary.html

• J. H. Graff "Color Atlas for Fiber Identification" The Institute of Paper Chemistry, Appleton, WI, 1940.

• Walter Rantanen. 'Fiber ID Course.' Integrated Paper Services. June 2013. Lecture.

• TAPPI Official Standard T401 om-08. Fiber analysis of paper and paperboard. 2008. http://www.tappi.org/Downloads/Test-Methods/UNTITLED-0104T401pdf.aspx