Polyamide

Synthetic material that has the ability to dry quickly and absorb little moisture, that is polyamide. Therefore, it is great for sportswear, functional and underwear, or swimsuits. You can also find it in coats, sweaters, or t-shirts. Polyamide is smooth and pleasant to the touch. It is also one of the most durable types of fabrics; tearing it takes some effort.

Polyamide fiber was invented by American Carothers in 1928, and commercial production was launched in 1938 (under the name nylon 66 at DuPont). Around the same time, experimental production of polyamide 6 began in Germany. Beyond these most well-known types, at least 30 variants of polyamide fibers were developed in the second half of the 20th century. The base material for all types is petroleum, which is transformed through chemical processes. In 2014, the global production reached approximately 3.7 million tons. In the Czech Republic, production of 700 tons was reported in 1989; from later periods, no manufacturer of polyamide fibers is known here.

And what are the characteristic properties of polyamide fibers? Most often mentioned is high strength both when dry and wet, high resistance to abrasion, along with high elasticity. Furthermore, the possibility of permanent pleating and stability against chemical agents, mainly alkalis. Other advantages also include very easy maintenance (washing, drying) and low specific weight, large specific volume.

Each wash increases the durability of polyamide fabrics or knits. Frequent washing is recommended, especially for polyamide 6 (silon, perlon, grilon). Many products are treated with anti-yellowing agents. A precise dose of special chemicals must be added to the washing bath, which does not react with this agent. Otherwise, the fabric or knit will turn gray after repeated washing. The iron temperature must not exceed 120 °C for pure polyamide products. Any symptoms of human skin hypersensitivity when wearing polyamide products are not caused by the fiber properties but by dyes, residues of detergents, and the like.

Then there are also aramid fibers. Aramid is a short form for the phrase aromatic polyamides. The compound is formed by connecting aromatic structures to the polyamide chain, where at least 85% of aramid groups must be directly linked to two aromatic rings. Aramid was primarily developed as a fiber resistant to high temperatures. The so-called meta-aramids (m-aramids) have a melting point above 400°C, are resistant to many chemicals, flexible, and easy to process in textile production. The most famous brand is Nomex. Another level of development is para-aramids (p-aramids) produced since the 1970s for example under the brand names Kevlar or Twaron. These fibers achieve extraordinarily high tensile strength at a low specific weight, comparable only to carbon fibers. Disadvantage is low resistance to light effects and easy charging with static electricity.