Xylan

Xylan (CAS number: 9014-63-5) is a group of hemicelluloses that are found in plant cell walls and some algae. Xylans are polysaccharides made from units of xylose (a pentose sugar). Xylans are almost as ubiquitous as cellulose in plant cell walls and contain predominantly β-D-xylose units linked as in cellulose.

Typically the content of xylans in hardwoods are 10 - 35 % of the hemicelluloses and in softwoods they are 10 - 15 % of the hemicelluloses. The main xylan component in hardwoods is O-acetyl-4-O-methylglucuronoxylan and in softwoods the main xylan components are arabino-4-O-methylglucuronoxylans. In general softwood xylans differ from hardwood xylans by the lack of acetyl groups and the presence of arabinose units linked by α-(1,3)-glycosidic bonds to the xylan backbone.

Some green algae contain xylan, especially macrophytic siphonous genera, where it replaces cellulose. Similarly, it replaces the inner fibrillar cell-wall layer of cellulose in some red algae.

Xylan is one of the foremost anti-nutritional factors in common use feedstuff raw materials.

Xylan (coating)

Xylan is a fluoropolymer-based industrial coating. Generally, it is applied in a thin film to the target material.

Applications

Xylan is generally used to reduce friction, improve wear resistance, and for non-stick applications. Additionally, it can be used to protect a metal from corrosion. The most commonly known application is in non-stick cookware but Xylan coatings have also been used extensively in the automotive industry and for corrosion protection in the oil and gas industry.

Xylan is the umbrella trademark for most of the Whitford Corporation fluoropolymer coatings line. Xylan is made of low friction, wear resistant composites of fluoropolymers and reinforcing binder resins. Xylan® coatings can be one-, two- (primer and top-coat), and three- (primer, mid-coat, top-coat) coat conventional and reinforced (filled) coating systems. The fluoropolymers utilized in Xylan coatings consist of PTFE, PFA, and FEP. The properties listed below may not apply to all Xylan coatings as the fluoropolymer and resin content and type can have significant effects on each property.