Silk Alternatives

Silk fabric has a very unique look and feel with efforts to duplicate the characteristics dating back centuries. Although the latest man-made efforts are getting closer, we still have a long way to go.

All fabrics are ultimately made from fibers which may be classified into two main categories – synthetic fibers, and natural fibers. Synthetic fibers are man-made by artificially controlled chemical reactions, while natural fibers are made from living organisms.

The list of synthetic man-made fibers is continually growing and currently consists of over 30 different names, some of which are full synthetics while others are classified as semi-synthetics. The list of natural fibers is much shorter and may be divided into two categories - animal fibers, and plant fibers.

Regardless of the fibers used for the construction of your next project, there are several very important questions that you should ask yourself before selecting a fabric which go beyond the immediate, “How does this look?” concern that all too many people have – especially in the world of fast fashion.

Synthetic Fibers

Consider what products are used in the construction of the fabric you decide to use and what will happen to your project at the end of its usable life when you decide to throw it away.

The most common synthetic man-made fiber, referred to as polyester, is derived from polymers made of purified terephthalic acid (PTA) or its dimethyl ester dimethyl terephthalate (DMT) mixed with monoethylene glycol (MEG) derived from petroleum. The resulting carbon intense mixture utilizing non-renewable resources is plastic.

Not only is this bad for the environment in the short term since the harmful chemicals and carcinogens can cause significant environmental damage if released untreated, but it is also bad in the long term since the majority of polyesters are not biodegradable. This means that the polyester item that you throw away today will remain at the landfill almost indefinitely.

Semi-Synthetic Fibers

Another important consideration, especially for apparel, is how your body will deal with the chemicals used to produce the fabric. Remember that your skin is the largest organ of the human body by surface area and the chemicals used for the construction of various fabrics will be in direct contact with you. Any chemical residue will be easily absorbed through the skin while other chemicals may be absorbed through the respiratory system as a result of chemical off-gassing.

In an effort to escape from the long list of chemicals commonly used for the construction of fully synthetic man-made fibers - which are essentially a form of plastic such as acrylic, nylon, olefin, polyester, and spandex - many people are choosing fabrics that are considered to be semi-synthetic.

Semi-synthetic fibers are produced from chemically treated natural products and are composed of regenerated cellulose, with rayon – a form of viscose – being the very first semi-synthetic fiber invented in 1846 and called artificial silk until 1924. Other examples of semi-synthetic fabrics include cupro, modal, and seacell.

Regenerated cellulose used to produce semi-synthetic viscose fibers are most commonly based on dissolved wood pulp from trees, bamboo, sugar cane, soy, and many other plants. The dissolved natural fibers are treated with:

  • sodium hydroxide,
  • carbon disulfide,
  • sulfuric acid.

The sulfur is then removed with sodium sulfide, and the impurities are bleached with sodium hypochlorite or hydrogen peroxide.

Looking at the OSHA (Occupational Safety and Health Administration) safety data sheet of only the carbon disulfide – a critical component in the manufacture of viscose – reveals an alarming list of hazards, including:

  • skin irritation,
  • eye irritation,
  • organ toxicity,
  • toxicity to reproduction, both in terms of fertility and to the unborn child.

The manufacture of viscose is a very chemical intense process and has been found to cause health issues in textile workers as well as the people living near viscose plants - particularly in countries which lack strictly enforced environmental legislation such as China, India, and Indonesia.

To add to the problem, countries which allow the market to be flooded with unethically produced inexpensive viscose make it substantially more challenging for environmentally responsible companies to compete.

Efforts to reduce the toxicity of manufacturing semi-synthetic fibers using regenerated cellulose have come a long way since the process was first invented. Through the continued development of newer manufacturing processes which use fewer toxic chemicals, and through better recovery of the toxic chemicals that must be used, the process is much cleaner now than it once was; however, it is by no means perfect.

The greatest issue now is how to supply the incredible amount of natural fibers that are required to start the manufacturing process of regenerated cellulose used to make semi-synthetic fabrics. Each year over 150 million trees are cut down for the production of cellulose-based fabric with no significant decrease in the foreseeable future.

The use of chemicals in processing the natural components of a semi-synthetic fiber along with other environmental issues such as massive global deforestation and countries which fail to have and enforce environmental legislation ensure that semi-synthetic fibers are not the best choice for fabrics. However, they will continue to be the most popular since they are best able to meet the ever-increasing global demand for fabric.

Natural Fibers

Natural fibers may be divided into two categories – animal fibers, and plant fibers. The most common natural fibers from plants include:

  • cotton,
  • flax,
  • hemp,
  • jute,

while the most common animal fibers include:

  • angora,
  • alpaca,
  • camel hair,
  • mohair,
  • silk,
  • wool.

There is much confusion as to when a fabric may be marketed as being made of natural fibers and when it becomes necessary to market it as being made of semi-synthetic fibers despite its source. Everything is dependent upon the process used to create the filaments used to make the threads which are woven together to make the fabric.

Even natural fibers such as bamboo that are broken down and re-assembled as a cellulose to form filaments cannot truly be classified as a natural fiber and must be marketed as a manufactured fiber. This is why when you shop for bamboo bed sheets, for example, they cannot be sold as made of bamboo, but instead must be labelled as rayon (or viscose) with the optional notation of made from bamboo.

The important thing to remember is that rayon from all cellulose sources is identical and that the characteristics of bamboo or whatever other natural fibers are used for the construction of the cellulose completely destroys the characteristics of the natural fiber.

This was an expensive lesson for numerous American companies that sold items as made of bamboo when they were actually made of rayon and resulted in the Federal Trade Commission (FTC) charging the companies with violations of the Textile Products Identification Act (Textile Act) and the FTC’s Textile Rules.

Of all the natural fibers, only silk is in a continuous filament form making it ideal for being spun into threads without having to undergo any process to form a filament.

To learn how silk is made be sure to read our page titled Silk, and to learn how silk fabric is made be sure to read our page titled Silk Fabric.

Although there are many natural fibers and man-made synthetic fibers available, the identical characteristics of silk have not been duplicated.