Synthetics

Synthetics

I have not spent much time on Synthetics as most people have had some exposure to them via Red Heart, Lion Brand, etc.  Companies.

Acrylic
Frequently found in combination with natural fibers, acrylics are synthetics that mimic wool, but without wool's insulating properties. Acrylics tend to be softer and bulkier than the polyamides, and some brands have even been compared to cashmere for softness.





Polyamide (Nylon)

Polyamide fiber is now commonly referred to as nylon, after the original Du Pont brand name for the polyamide produced by that company. Nylon is very strong, durable, lightweight, easy to care for (can be machine washed and dried), and elastic, which makes it perfect for blending with other fibers to produce hard-wearing sock yarns. Tactel is a brand name for a very soft nylon fibre.

Polyester
Polyesters are very easy to care for. They are extraordinarily wrinkle resistant even when wet and hold their shape well. The fibers' strength is useful when combined with other fibres to add strength and stability to the end result.




Other Synthetics
Many yarns are now available which are made from unconventional materials and processes, such as novelty eyelash and pigtail, paper-like yarns, string, ribbon, and shoelace-type yarns.

Elastic fiber is sometimes spun with another yarn to help less resilient yarns keep their shape. Yarns with elastic content are excellent for making fitted garments. Elite is a brand name of a polyester elastic fiber. Elastic thread is used as a carry-along with yarn while knitting or crocheting, or woven into the fabric when the garment is complete, usually along the edges.

Metallic fibers add a special touch in yarns and are often blended with other fibres for strength. The type of metallic fibre commonly used in yarns is a form of polyester treated with vaporized metal and then bonded on both sides with a film. Another type of metallic fiber is made from very thin metallic foil, coated with plastic film, and cut into narrow strips for spinning. Fine metal wire can be used for knitted or crocheted jewelry and other accessories.

Polypropylene, like other synthetics, is spun into yarn to resemble the texture of natural fibers. It is inexpensive to produce, lightweight, and has good insulating properties. It can easily be spun into yarns that mimic wool.

Vinyl yarn is durable, with a glossy appearance. It is ideal for accessories.