Lycra, also known as spandex or elastane, is a highly elastic synthetic fabric that can stretch to 5-8 times its usual size. Lycra is a brand name for elastane, and these fabrics are all the same material. Lycra is a fully synthetic fiber, which means that all of its components are created in laboratory settings. It is composed of long chains of monomers that are connected with a special type of acid. Lycra is often blended with other textile types to increase its stretch. For instance, if Lycra is woven in wool, cotton, or polyester, the fabric is much stretchier. The increase in elasticity can be determined once Lycra is combined with another fabric. If 10% Lycra is added to the rigid fabric, it can expand roughly two times its normal size.
There is no technical difference between Lycra and spandex. Both Lycra and spandex are the same. Spandex is the generic name of the fiber, and Lycra is a spandex product of DuPont company. When you are specifically using Lycra® product (spandex fiber) for your clothing products, if you name it Lycra, there is no issue. But when you use spandex fiber manufactured by other companies, it is better to call it spandex rather than Lycra.
There is no difference in fabric properties between cotton/spandex and cotton/Lycra blends. The fabric properties will vary based on what percentages of elastane (spandex) are used.
