The effect of physical factors on the process of physical-mechanical degumming of flax fibers

Abstract

This paper presents results of studies on a new physical-mechanical method of degumming of flax fibers in order to determine optimal parameters of the process for obtaining high-quality fiber.The study was carried out on an experimental device where lengthwise and crosswise flow of the liquid through a straw batch was applied and where the following process parameters were controlled: temperature, flow velocity, and time of the process. The pH was maintained at a stable neutral level. The degumming process was evaluated by measurement of the mass loss of the straw during the process, by physical-chemical tests of the process liquid, by metrological and chemical tests of the obtained fiber, and by statistical analysis of the results. The results of the study, compared with the results of traditional warm water retting, indicate that by proper selection of physical factors of the process, it can be intensified resulting in obtaining high-quality fiber, superior to the fiber obtained in the traditional retting technique.Keywords physical-mechanical degumming of fibrous plants, physical factors, flax fiber, diffusion, lengthwise and crosswise liquid flow, process optimization Bast fibers are enjoying a renaissance because of the development of new applications, which are in accordance with the principles of sustainable growth. The European Technology Platform for the Future of Textiles and Clothing regards bast fibers of flax and hemp as raw materials of special importance for Europe, the so-called ''Textile Flagship for Europe'', that is, a factor that has a strong effect on the attractiveness of the market, with potential to cope with societal and economic challenges of European industry. However, in order to meet the objectives of European Flagship, flax fibers must be characterized with a completely new quality and become an alternative for the fiber obtained in the traditional way. The application of flax fiber in the clothing sector, which makes use of its beneficial effect on physiological parameters of human body, 1,2 and in technical applications as reinforcement for structural composites 3-7 requires high quality that will guarantee obtaining final products with new desired competitive properties. Therefore, it is important to carry out studies on development of a method of obtaining high-quality bast fiber, the quality of which depends on the extraction method, the number of elementary fibers in the stem, distribution structure, and binding of fibers within bundles. Extraction of fibers from the plant relies on degumming of fibrous straw in an aqueous environment where biological, chemical, and physical processes occur. [8][9][10][11] Currently, a method commonly used in central Europe of separating ligneous parts of stems from fibers, extracting them and removing the non-cellulosic Downloaded from residues is the so-called dew retting, that is, retting of the fibrous plants on the fields. The retting process involves spreading the straw on the ground, where it is subjected to moisture and later to microbi...

Antioxidant Potential of Hemp and Flax Fibers Depending on Their Chemical Composition

“…The osmotic degumming method is based on natural physical laws: water diffusion, osmosis and osmotic pressure to obtain the higher quality of fibers. The process was supported by ultrasound treatment [ 26 , 27 ].…”

Evaluation of Antibacterial Activity of Flax Fibres Against the [i]Staphylococcus aureus[/i] Bacteria Strain

“…n Hemicellulose content in % was determined according to the Polish Standard BN-77/7529-02. The percentage of hemicellulose content was determine by dissolving hemicellulose contained in fiber with 1% sodium hydroxide, draining, drying and calculation of hemicellulose content based on weight loss [26].…”

Cottonisation of Decorticated Flax Fibres

“…It is known that each extraction process, such as decortication, water retting, dew retting as well as enzymatic, chemical, physical or any other treatment of fibre affects, to varying degrees, the degumming of fibre from the woody part, which is caused by the reduction in pectins, lignin, hemicellulose, waxes and fats in the fibre itself, leading to the removal of impurities and the division of fibre slivers into smaller thinner complexes. Therefore fibre parameters such as: length, linear mass, tenacity, homogeneity and efficiency depend on the extraction technique [12]. The results of chemical analyses of the fibre composition after each stage of the processing are presented in Figures 8-12.…”