What are the properties of cuprammonium rayon?

Among the other types of man-made fibers, cuprammonium rayon is known to be the closest resemblance to silk fiber. Hence, this fiber is often used as a replacement for the traditional clothing items which are made from silk.
Let’s see what are the properties of this material:

• Cross-section: Cuprammonium rayon has usually round and smooth cross-section appearance but sometimes it is also oval in shape.
• Surface appearance: The surface texture and appearance of cuprammonium rayon filaments have a uniform appearance with no markings in the longitudinal view.
• Durability: When compared to other rayon derivatives this fiber is not much durable.
• Breathability: This fabric has good breathability that controls moisture and keeps the wearer cool, fresh and comfortable.
• Fineness: Fineness of cuprammonium rayon is one of its most important properties as these fibers can be made with extreme fineness. This material can be made into very fine filaments due to the stretch which is applied to filaments during the spinning process. When compared to viscose rayon which has a fineness of around 2.5 denier, cuprammonium rayon filaments can be produced as fine as 1.33 deniers which gives it a soft feel of silk fiber.
• Sheerness: Due to fine filaments, sheer and lightweight textiles can be made from cuprammonium rayon fibers with desirable draping properties
• Tensile strength: Cuprammonium rayon has an average tensile strength of 1.7-2.3P in dry state and 0.9-2.5P in the wet state.
• Density: Since a larger portion of the cuprammonium rayon fiber has amorphous regions hence the average density is lower than that of cotton fiber. This is why rayon reacts very easily to chemicals in comparison to cotton.
• Absorbency: Among all other cellulosic fibers, cuprammonium rayon has the best absorbency property. It is even better than cotton and linen. This allows the textile made from this fiber to absorb moisture and release it in the outside environment keeping the wearer cool and comfortable.
• Easily blendable: Cuprammonium rayon can be easily blended with other fabrics.
• Elongation at break: In dry state cuprammonium rayon has an elongation at break of 10-17%.
• Moisture Regain: At 70°F and 65% relative humidity, cuprammonium rayon has a moisture regain of around 11%.
• Dye absorption: Direct dyes are the most suitable dyes for cuprammonium rayon. When compared to viscose rayon, deeper shades can be obtained in cuprammonium rayon with direct dyes.
• Reaction with flame: Similar to viscose rayon, cuprammonium rayon also burns rapidly and chars at 180° C. The leftover ash and residue contain significant concentrations of copper.
• Sunlight Exposure: In the presence of oxygen and moisture the strength of cuprammonium rayon degrades when exposed to sunlight.

Unlike other natural fibers, hot water cannot be used for laundering cuprammonium rayon otherwise, its quality will be degraded.