Technologies Involved in the Manufacture of Smart Nonwoven Fabrics

Many methods can be used to protect humans against hazardous chemicals in the environment such as personal protective equipment and protective clothing. However, what matters most is prevention and early detection of threats. Detecting the presence of hazardous chemicals such as organic liquids and the vapours they give off is possible using sensors. Effective chemosensory properties are revealed by conductive polymers and carbon particles, where the electrical resistance of chemicals changes. Still open to debate is finding the optimum means of applying chemical sensors that would provide high sensitivity, durability, reliability, and resistance but at the same time would not be expensive. The authors propose introducing chemical sensors in the form of nonwoven fabrics produced by the melt-blown method and by electrospinning. The analysis takes account of melt-blown nonwoven fabric ​​based on polylactide (PLA)-containing carbon nanotubes, nonwoven fabric made by electrospinning based on polyethylene oxide–containing carbon nanotubes and carbon nonwoven fabric from polyacrylonitrile submicron precursor fibres formed by electrospinning. Assessment of the effectiveness of the sensors to liquid vapours including methanol, acetone, benzene and toluene (concentration 200 ppm) has been carried out. The resulting nonwoven sensors are characterized by good electrical conductivity and altered electrical resistance as a result of the presence of vapours

Bio-Based Composites for Sound Absorption

The acoustic thermoplastic composites and a method for their production with the participation of the bio-components were presented. To form composite matrix polylactide fibres (PLA) were used. Natural fibres (flax (LI) and cotton (CO)), straw and cellulose ultra-short/ultra-fine fibres obtained from biomass were used as a reinforcement. Cellulose ultra-short/ultra-fine fibres were obtained from the flax fibres or straw by enzymatic treatment and optionally modified by silane. The tensile stress at maximum load of composites with the sub-microfibres obtained from waste flax fibres after silane modification is twice higher than that of the composite with the sub-microfibres without the silane modification

Naturalny Jedwab – niezwykłe włókno: pochodzenie, przetwórstwo i produkcja światowa

The article presents the history of the development of sericulture in the world, including Poland. The advantages of natural silk which cause interest in its production and processing in many countries of the world are indicated. A brief description of mulberry silkworm breeding and the technology of silk processing into textile products are presented. The article provides information on the production of natural silk in several countries in 2015-2019. The share of silk in the world global production of fibres is about 0.2%. Over the last few years, the largest amounts of natural silk have been produced by the following countries: China, India and Uzbekistan – the total share of these countries in the world silk production is about 98%.W artykule przedstawiono historię rozwoju jedwabnictwa w świecie, w tym również w Polsce. Wskazano na walory jedwabiu naturalnego, które powodują zainteresowanie jego produkcją i przetwarzaniem w wielu krajach świata. Przedstawiono także hodowlę jedwabnika morwowego oraz technologię przetwarzania jedwabiu na wyroby. W artykule zawarto dane statystyczne produkcji jedwabiu naturalnego dziewiętnastu krajów w ciągu ostatnich pięciu lat (2015-2019). Udział w produkcji jedwabiu na rynku tekstylnym wynosi około 0,2%. Główne kraje produkujące jedwab naturalny to: Chiny (63%), Indie (32,9%) i Uzbekistan (1,6%) – łączny udział tych krajów w światowej produkcji wynosi 97,5%

Multilayer Nonwoven Inserts with Aerogel/PCMs for the Improvement of Thermophysiological Comfort in Protective Clothing against the Cold

This study aimed to assess the developed nonwoven inserts with aerogel/PCM (phase change material) microcapsules for use in protective clothing against cold in terms of properties related to thermophysiological comfort. These inserts were obtained by the thermal bonding of a multilayer system consisting of needled-punched nonwovens and silica aerogel particles and/or PCM microcapsules evenly distributed between them. The influence of aerogel and PCM microcapsules on the basic physical properties of inserts, their microstructure, air permeability, and water vapor resistance was investigated and analyzed. The thermal insulation properties of inserts were assessed based on thermal conductivity results. The inserts with PCMs were also tested for their ability to regulate the temperature in the undergarment microclimate using the differential scanning calorimeter (DSC) and the “skin model” device. The research showed that the use of aerogel allowed for reducing the thermal conductivity of the insert by approximately 13% compared to the insert without additives. The high values obtained of the melting and crystallization enthalpy of inserts with PCMs confirmed their high efficiency in the heat absorption and release. Thus, the use of aerogel and PCMs in protective clothing against cold seems to be an effective solution for improving its protective properties and actively adapting its thermal insulation to the changing temperature conditions and the activity level of employees

3-dimensional computer model of electrospinning multicapillary unit used for electrostatic field analysis

Electrospinning is an experimental method of the polymer super thin fibres formation using the electrostatic field. The distribution of electrostatic field affects the effectiveness of the electrospinning. In order to analyse the electrostatic field for given technological parameters the 3-D computer model of an electrospinning device must be applied