TRC Distribution, Inc.

CORK CHEMICAL COMPOSITION

© 2002 by CTCOR
Cork cells have the shape of straight-sided pentagonal or hexagonal prisms.

The average chemical composition of cork is:

Suberin (45%) - the main component of the cell walls; responsible for the resilience of the cork
Lignin (27%) - the binding compound
Polysaccharides (12%) - components of the cell walls which help define the texture of the cork
Tannins (6%) - polyphenolic compounds responsible for color
Ceroids (5%) - hydrophobic compounds that ensure the imperviousness of cork
Mineral water, glycerine, and others make up the remaining 4%.

Cork cells are a minute, straight-sided pentagonal or hexagonal prism. The cell height rarely exceeds 0.045 millimeters but decreases to 0.02 to 0.01 millimeters in the last cork bark formed in the autumn. Following the invention of the optical microscope in the 1660s, the British scientist Robert Hooke was the first to observe the structure of cork, for which he coined the term 'cell'.

50 per cent of cork is gas enclosed in the cells. Suberose sacs make the cork cell membrane impermeable and the cell airtight.

Suberin, a mixture of fatty acids and heavy organic alcohols, is the basic substance of cork. Impermeable to gas or liquid, it is also fire and insect resistant and unaffected by water.

Natural cork is:

Natural, recyclable and biodegradable
Very light
Elastic, compressible and impermeable
An efficient insulator for acoustics, heat and mechanical vibration
Highly resistant to wear and tear