Properties of Viscose Rayon

Rayon as a fabric is soft and comfortable. It drapes well which is why it is highly sought after as an apparel fabric. Most characteristics are variable depending on processing, additives and other finishing treatments and fabric construction.

Physical Properties

Moisture Absorption

It absorbs more moisture than cotton. Moisture Content of Cotton is 6% at 70F whereas for Viscose Rayon, it is 13% under the same conditions.

Tensile Strength

The Tensile Strength of the fiber is greater when the fiber is dry as compared to its wet state. Because of this, it stretches and shrinks more than cotton. It is 1.5-2.4 gpd in the dry state and 0.7-1.2 gpd in the wet state. For high tenacity variety the values are 3-4.6 gpd and 1.9 to 3.0 gpd respectively.

Elasticity

The elasticity of Viscose Rayon is less than 2-3%. This is very important in handling viscose yarns during weaving, stentering etc. when sudden tensions are applied.

Elongation at Break

Ordinary Viscose rayon has 15-30% elongation at break, while high tenacity rayon has only 9-17% elongation at break.

Density

The density of Viscose rayon is 1.53 g/cm3. Rayon filaments are available in three densities: 1.5, 3.0 and 4.5.

Action of Heat and Light

At 300^o F or more, Viscose Rayon loses its strength and begins to decompose at 350-400^o F. Prolonged exposure to sunlight also weakens the fiber due to moisture and ultraviolet light of the sunlight.

Absorbency

Rayon is the most absorbent of all cellulosic fibers, even more so than cotton or linen. Rayon absorbs perspiration and allows it to evaporate away from skin which makes it an excellent summer fabric. Its high absorbency equally applies to dyes as well giving them deep and thick colors.

Abrasion Resistance

Its abrasion resistance is very low thanks to the inelasticity of rayon. It is easily damaged by scraping.

Tenacity

Tenacity of viscose rayon is 2.4-3.2 gpd.

Moisture Regain

Moisture regain is 11-13%.

Chemical Properties

Action of Acids

The resistance of regenerated cellulose rayon's to acids is generally less than that of cotton. Organic acids can be safely used in 1 to 2 percent concentration without injury to the fiber. Inorganic acids such as hydrochloric & nitric can be used in surprisingly strong concentrations provided the temperatures are not too high and the treatment is brief. At high temperatures and concentrations all acid will destroy or carbonize regenerated rayon's. Inshort, it is damaged by strong acids but it is moderate with weak acids.

Action of Bases

Viscose rayon has a good resistance to weak alkalis but strong alkalis can harm theses fibers thoroughly.

Action of Dry Heat

Viscose Rayon, under the influence of heat as well as light, shows rapid loss in strength. Degradation of cellulose is lower in the absence of oxygen. Continued heating in the absence of oxygen leads to deterioration of the cellulose.

Action of Solvents

Textile solvents can be used on Viscose rayon without any deteriorating effect. For example, Viscose rayon dissolves in cuprammonium hydroxide solution.

Effect of Iron

Contact with iron in the form of ferrous hydroxide weakens viscose rayon yarns. Therefore, staining, marking or touching of rayon to iron or iron surface should be avoided.

Action of Microorganisms

Microorganisms (molds, mildew, fungus, bacteria) affect the color, strength, dyeing properties and luster of rayon. Clean and dry viscose rayon is rarely attacked by mildew.

Follow me on Facebook