ДОСЛІДЖЕННЯ СОРБЦІЙНИХ ВЛАСТИВОСТЕЙ ВОЛОКНИСТИХ МАТЕРІАЛІВ, МОДИФІКОВАНИХ ГЛИНИСТИМИ МІНЕРАЛАМИ

The paper presents the results of determining the sorption properties of nonwoven materials modified with clay minerals, obtained on the basis of fibrous waste, in relation to the methylene blue indicator to determine the possibility of using the created materials in the purification of light industry wastewater from dyes and heavy metal ions.Purpose. Determination of kinetic regularities of sorption (by methylene blue) of fibrous nonwoven materials modified with different types and amounts of clay adsorbents.Methodology. Nonwovens obtained from elastic fibrous waste of the textile industry were used as a basis in the work. They consisted of Lycra 162 C (PU) complex fibers and Nylon 6.6 f20 / 1 (PA-6.6) fibers in a ratio of 70/30 wt. %. For bonding the nonwoven material, adhesive bicomponent fibers Acebon 4/51 black (4 den) (BVCh) (20 wt%) were added to the initial composition. To enhance the sorption capacity of the PU / PA / BV 80/20 fabric, powders of montmorillonite clay (clay grade PBA-18) and palygorskite (clay grade PP-5) type were introduced in an amount of up to 40% by weight of the nonwoven material. Evaluation of the sorption properties of modified fibrous materials with different clay adsorbents was performed by determining the change in the optical density of MS solutions of a given concentration.Scientific novelty. It was found that fibrous materials modified by the studied samples of montmorillonite and paligorskite clays show high absorption capacity relative to the methylene blue dye due to its multilayer sorption. After 24 hours of processing, the degree of absorption is 70% when using clay brand PBA-18 in the amount of 40% by weight of the fibrous material, which is higher than when using clay brand PP-5 (45%) under the same conditions.Practical value. Sorption materials modified with clay minerals can be further used to treat wastewater from light and chemical industries from heavy metal ions.

Waterborne and Airborne Microfibers Shed from Non-Woven Materials in Water and Air Environments

Nonwoven products are widely used in various fields, including many disposable products, such as wipes, diapers, and masks. However, microfibers shed from these products in the aquatic and air environment have not been fully described. In the present study, several commercial single-use nonwoven products and a series of meltblown nonwoven materials produced in a pilot plant were investigated regarding their microfiber generation during their use in aquatic and air environments. Microfibers shed in water were studied using a Launder Ometer equipment (1- 65 mg of microfibers per gram material), and microfibers shed in air were evaluated using a dusting testing machine that shakes a piece of the nonwoven back and forth (~0 to 6000 microfibers (4 mg of microfibers) per gram material). The raw materials and bonding technologies applied to the commercial nonwovens affected the microfiber generation both in water and air conditions. Meltblown nonwoven fabrics generated fewer microfibers compared to the other commercial nonwovens studied here, and the manufacturing factors, such as DCD (Die to collector distance) and air flow rate, affected the tendency of microfiber generation. Microfibers of nonwovens shed in water and air environment were compared to selected textile materials and paper tissue materials. The results herein suggest that it is possible to control the tendency of microfiber shedding through the choice of operating parameters during nonwoven manufacturing processes.

Preparation and properties of fluffy high-shrinkage polyester/polyamide 6 hollow segmented pie microfiber nonwovens

Bicomponent spunbond hydroentanglement technology can break the interface between the two components by physical extrusion and shearing, thereby realizing the green and efficient production of high-strength microfiber nonwoven materials. Herein, we report a soft and fluffy bicomponent spunbond hydroentanglement nonwoven material using high-shrinkage polyester/polyamide 6 (HSPET/PA6) as the bicomponent. HSPET/PA6 hollow segmented pie composite fibers with different volume ratios were prepared by spunbond technology, the HSPET and PA6 segments were alternately arranged, and the interface was flat. The composite fibers were split by heat treatment. The dry heat shrinkage rates of the composite fibers were 8.45% (50/50) and 10.57% (70/30), and the boiling water shrinkage rates were 10.02% (50/50) and 12.27% (70/30). HSPET/PA6 hollow segmented pie microfiber nonwovens were prepared by hydroentanglement technology. After heat treatment, the fibers of nonwovens were further split and the HSPET fibers curled, giving the nonwovens a fluffy characteristic. By comparing the properties of HSPET/PA6 after heat treatment, the shrinkage effect of the water bath was obviously better than that of dry heat, and the split degree of fibers reached 81.97% (50/50) and 84.65% (70/30). Compared with polyester/PA6 nonwovens, the softness of HSPET/PA6 nonwovens increased by 45.1% (50/50) and 49.3% (70/30) after boiling water shrinkage. At the same time, the mechanical properties of HSPET/PA6 nonwovens were also improved. The successful fabrication of HSPET/PA6 microfiber nonwovens provides a new method for enhancing the softness of bicomponent spunbond hydroentanglement nonwovens.

Analysis of the effect of ionizing radiation on the properties of bulk nonwoven material

At the moment, there is a wide range of bulky nonwovens for various purposes on the market. One of the important areas of using such materials is healthcare. In particular, bulky nonwoven materials are intended for the manufacture of wound dressings, evacuation kits for newborns. Disposable medical devices of this kind are usually subjected to radiation sterilization. As is known from earlier studies, radiation sterilization significantly affects the performance of nonwovens. In this regard, for nonwoven materials for medical use, an important characteristic is the stability of indicators after exposure to radiation sterilization. As a result of the study of bulk nonwovens Holofiber ® after radiation radiation in the dose range from 20-60 kGy, there were no significant changes in operational performance. The stiffness increased by an average of 3-10%. The stiffness indicators after ionizing radiation according to GOST 24684 also meet the requirements. The value of electrification increased due to an increase in the static field under the action of ionizing radiation. It is worth noting that the values of electrification are within the norm established by GOST 32995. The breaking load varies from 1-5%. Thus, non-woven materials Holofiber ® PROFI, article P 35191, Holofiber ® SOFT, article P 5197, Holofiber ® SOFT, article P 5200 are recommended for the production of medical devices.

Dry vs. wet testing: quasi-static tensile experiment setup for polymer based biomaterials

Polymer materials can be manufactured with high reproducibility and do offer the potential for chemical modification. This enables matrix property modification and fine-tuning of several material characteristics, such as tissue-implant interaction, inflammatory potential or susceptibility to biofilm formation. Whereas manufacturing protocols are crucial for the resulting material properties, also the evaluation in terms of performance and safety has to be considered. Regarding this, both, temperature and composition of test medium may affect the physicochemical properties of implant materials. The present study addresses the influence of test medium compared to dry test conditions, each at two different temperatures, on the mechanical properties of elastomeric film and nonwoven materials.

Fiber statistics of nonwoven materials by SEM images - influence of number of images

Electrospun nonwovens are widely applied in biomedicine and various other fields. For control of the manufacturing process and quality assurance Scanning electron microscopy (SEM) imaging is one standard practice. In this study, statistical datasets of 60 SEM images of three nonwoven samples were evaluated using Gaussian fit to obtain numerical results of their fiber diameter distributions. The question of how much effort is required for acceptable imaging and processing is being discussed. As determined here, for reliable statistics, a minimum surface area of the nonwoven has to be evaluated. The fiber diameter should be in a range of approximately 2 - 3% of the edge length of the square equivalent of the evaluated image area, using sufficiently magnified SEM images, in which the fiber diameter is imaged over at least 30 pixels.

Features of Thermomechanical Stability of Anionic–Cation Exchange Matrix “Polikon AC” on Viscose Non-Woven Materials

The thermomechanical stability of the anion–cation exchange matrix “Polikon AC” on viscose nonwoven materials is investigated. In this work, a molecular model of a solvation environment for experimentally obtained “Polikon AC” mosaic membranes is refined. Mosaic membranes on a viscose fiber base were fabricated by the method of polycondensation filling. The temperature dependence of deformation was investigated for dry and wet anion and cation exchange membrane components at a constant tensile load of 1.5 N and a heating rate of 8 °C/min. The effect of moisture content on the deformation of anionite and cationite fragments under a constant external tensile load of 1.5 and 3 N in a temperature range up to 100 °C was studied.

Influence of Gamma and Electron Radiation on the Strength Characteristics of Nonwoven SMS Materials Based on Polypropylene

Radiation sterilization is widely used to sterilize nonwoven SMS medical products. SMS materials have improved filtering and barrier properties, low bacteriopermeability and, due to these properties, are indispensable for medicine. They are used to make such important health care products as disposable surgical clothing and underwear. As a result of the research carried out, the effect of gamma and electron radiation, in the range of absorbed doses from 15 to 25 kGy, on the strength characteristics of nonwoven SMS materials based on polypropylene with a surface density of 35, 40, 50 g/cm2 was studied. It has been established that the strength characteristics (tensile strength, tensile strength, and tear strength) of nonwoven materials decrease after exposure to ionizing radiation. The higher the density of the material, the more its characteristics decrease after radiation sterilization. It was also found that gamma radiation, due to its nature, has a stronger effect on nonwoven materials based on polypropylene, and leads to a stronger decrease in strength characteristics. In general, for products sterilized by ionizing radiation and made from SMS materials, it is important to control the strength characteristics, primarily, the tensile strength in the transverse direction of the web stuff.