Spandex

The key linking reaction is formation or the urea (aka urethane): The polyurea is usually treated with various diamines, which function as chain extenders.

A benefit of spandex is its significant strength and elasticity and its ability to return to the original shape after stretching and faster drying than ordinary fabrics.

For clothing, spandex is usually mixed with cotton or polyester, and accounts for a small percentage of the final fabric, which therefore retains most of the look and feel of the other fibers.

In the early 1950s chemist Joseph C. Shivers modified Dacron polyester, producing an elastic fiber that could withstand high temperatures.

[12] DuPont launched an extensive publicity campaign for its Lycra brand, taking advertisements and full-page ads in top women's magazines.

[13] By the mid-1970s, with the emergence of the women's liberation movement, girdle sales began to drop as they came to be associated with anti-independence and emblematic of an era that was quickly passing away.

In the 1990s a variety of other items made with spandex proved popular, including a successful line of body-shaping foundation garments sold under the trade name Bodyslimmers.

As the decade progressed, shirts, pants, dresses, and even shoes were being made with spandex blends, and mass-market retailers like Banana Republic were even using it for menswear.