Mastering Hemp Fiber Markets

Posted 09/08/22

Fibers are currently used in a multitude of industries. And fibers made from hemp have the potential to be integrated into numerous, diverse enterprises. As companies move away from petrochemicals and fiberglass, hemp is poised to supplant synthetics as a renewable and sustainable solution to environmental concerns.

The modern use of fibers is vast and includes industries such as electronics, telecommunications, textiles, aerospace, defense, construction, automotive, and sporting goods. The added benefit of eco-friendly natural fibers makes them a growing commodity. Whether it's due to new ecological construction concepts, regulations, certifications, health issues, or the environmental impact of product manufacturing, use, and disposal – industries are increasingly relying on environmentally friendly filling and insulating materials made of pulp or fibers.

While natural fiber products are conquering more and more industrial and consumer fields, it's not just for environmental reasons. In the food and beverage industry, natural fibers can replace plastic wrapping, increasing food safety with improved properties for food preservation. The automotive industry has started using plant fibers for manufacturing lightweight car bodies. And the construction industry is always looking for ways to improve efficacy. The performance of natural insulating materials is equivalent to that of many mineral and synthetics. But natural insulating materials are less risky for the installer. Furthermore, natural fibers are usually harmless and easier to handle for disposal.

Industries that utilize fibers all have their unique set of requirements. These specifications are numerous and can include length, thickness, strength, absorbency, bonding, weight, color, stretch, conductivity, heat capacity, risk to health, and biodegradability.

“Industries which utilize fibers all have their unique set of requirements”

In its raw form, hemp bast fibers exist bound together in the bark of the hemp stalk. The first step to make them available is to separate the bark fibers from the hurd in a process known as decortication. But this process needs to be specific to the market for the fibers.

Bast fibers destined for textiles require the hemp to be grown for fiber and harvested prior to flowering to keep lignin levels low. The bast fibers need to be at least 36” long and clean of any hurd. This is similar to flax fibers used to make linen. They should not be bent or tangled, and aligned in the same direction. This requires a specific method of decortication to achieve these qualities. These bast fibers do not need to be combed or separated from one another at this stage since that process will be done at the textile factory.

Hemp fibers obtained from a grain crop require a different type of decortication since they will be shorter, drier, and have higher levels of lignin. Different methods of decortication are going to result in different qualities of fiber. They may be shorter, less uniform in length, tangled, and have bits of hurd attached. Marketing these fibers will require further refinement and selection to increase their range of uses.

Both hemp grown for fiber or grain contains bast fibers which are held together by lignin. They frequently need to be separated from one another by either physically combing them or chemically removing the lignin in a process known as degumming. Both processes can thin the fibers as well as shorten their length. Once the fibers are separated from one another, they may be further sorted based on length and thickness. Other machinery exists to reduce the fibers even further in a process known as reduction. Every application for fibers is unique and requires its own set of parameters.

Hemp core fibers do not undergo the process of combing and degumming, but they still need to be standardized in length and thickness to be useful in specific applications. Hammer mills and screens are used to achieve this uniformity.

Not only do fibers need to be a certain length or thickness, they frequently need to be uniform. The average difference in length and/or thickness between the fibers is referred to as standard deviation. Some applications can accept a greater tolerance of variation than others depending on their use.

Cleanliness is also an issue. Fibers need to be free of small particles or contamination. Applications such as pulp for paper and composites may require a purity of greater than 99.9%. Other products do not require such a degree of cleanliness.

Color may also play a factor in the hemp fiber. The natural color of hemp can vary from yellowish-white to green to brown to dark gray. The color depends upon the strain of hemp grown, the length of the grow, the method of harvesting and retting, as well as the processing technique. To get a consistent color, fibers may need to be bleached or dyed.

“The successful entrepreneur will need to consider all these parameters and understand the needs of their target customers”

How does all this information relate to the hemp industry as a whole? The successful entrepreneur will need to consider all these parameters and understand the needs of their target customers. Once the hemp fiber is harvested, processing facilities will be required to modify their fibers to fit their client’s expectations. Having the ability to adjust the fibers for length, width, and color opens the door to multiple industries and clientele. Uniformity of the fibers is part of the quality control. The companies that can master the manipulation of hemp fibers and provide consistent quality will expand their markets and be the most successful.