A critical review of characterization and measurement of textile-grade hemp fiber

The legalization of hemp production in the United States (US) in 2018 triggered a boom of research and development to apply the newfound resource. The textile industry, one of the most notable polluters in the world, looked to hemp as a more sustainable alternative to a multitude of fibers, including cotton. After discovering the numerous benefits of hemp, demand for hemp textile production rapidly increased. However, currently, there is little to no guidance in the US for evaluating the properties of hemp to determine its ability to be made into a fiber. Fiber properties are measured for natural and synthetic fibers to ensure that the final product will perform adequately and is a necessary step in the textile production process. Therefore, to aid in the development of a more efficient industrial hemp production in the US, the purpose of this research was to evaluate the current characterization methods used for cotton, flax, wool, hemp (in China), etc. and determine their applicability for hemp textile fibers in the United States. The measurements chosen were based on the necessary information for spinning mills to produce high quality hemp fiber. Test methods of fiber length, width, linear density, tensile strength, cohesion, cleanliness, density, oil content, and color were reviewed and discussed. This review may shed new lights on the hemp fiber characterization and measurement in the textile industry.