RESUMO
The article presents the results of research on the impact of the use of an original, innovative method of deposition of Parylene C on the functional properties of fabrics with various potential applications (e.g., thermal and chemical protective clothing, packaging, covers and others). Verification of the effects of the method used was based on interdisciplinary research taking into account the impact of coating fabrics on changes in their structure (micro-CT), surface properties (contact angle), barrier properties (water and chemical liquid wetting), electrostatic properties (charge decay), biophysical properties describing heat and mass transfer (by the Alambeta system and thermal imaging) and flammable properties. Four fabrics made of synthetic organic fibres (meta-aramid, para-aramid) and natural inorganic fibres (basalt) were selected for testing. Given the complex structure of textile substrates, the results confirmed that the two assumed thicknesses of the Parylene C coating were consistent with the actual measurements. The findings indicated that the coatings significantly reduced water and acid absorption in the fabrics compared to unmodified ones. Thermal insulation property tests revealed that coated fabrics exhibited higher thermal conductivity than unmodified fabrics. Additionally, the presence of Parylene C on aramid fabrics resulted in a modest increase in their ignition resistance.
RESUMO
The electric vehicle (EV) market, together with photovoltaic (PV) installations continues to develop at a pace. However, there are concerns that EV and PV installation fires may create more harmful substances than other types of fire. PV modules and car battery fires emit a range of carcinogenic and highly toxic compounds that are not yet fully understood and may pose a threat to firefighters' health. This also raises the question of the impact on firefighters' clothing and the safe handling and cleaning after such fires. This article presents a literature and standards review of the firefighters' protective clothing maintenance and cleaning. It also contains test results showing that firefighters' clothes accumulate harmful substances after fighting these types of fires. Pilot tests for the presence of polycyclic aromatic hydrocarbons (PAHs) and formaldehyde showed that levels exceeded limits in all clothing samples. For example, the cobalt level was 24 times higher than that considered safe in the test carried out with car battery fire. Although it is recognized that liquid carbon dioxide (LCO2) methods of cleaning may be more effective than traditional water washing, further research on cleaning efficiency for clothing containing substances emitted from car battery and PV modules fires is required.
Assuntos
Poluentes Ocupacionais do Ar , Bombeiros , Incêndios , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Ocupacionais do Ar/análise , Dióxido de Carbono , Cobalto , Formaldeído , Humanos , Exposição Ocupacional/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Roupa de Proteção , ÁguaRESUMO
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.
RESUMO
In this work, beeswax was used for the first time for finishing polyester/Cotton/Viscose blend fabric and polyester fabric. The aims of the study were: (1) to characterize the composition of beeswax (using Gas Chromatography Mass Spectrometry, GC-MS and 109AgNPET laser desorption/ionization mass spectrometry (LDI MS); (2) to develop a laboratory method for applying beeswax; (3) to assess the antimicrobial activity of beeswax fabrics against bacteria and fungi (AATCC 100-2004 test); and (4) to assess the properties of textiles modified by beeswax. Beeswax was composed of fatty acids, monoacyl esters, glyceride esters and more complex lipids. The bioactivity of modified fabrics was from -0.09 to 1.55. The highest biocidal activity (>1) was obtained for both fabrics against A. niger mold. The beeswax modification process neither affected the morphological structure of the fibers (the wax evenly covered the surface of the fibers) nor their color. The only statistically significant changes observed were in the mechanical properties of the fabrics. The results obtained indicate that modification of fabrics with beeswax may endow them with biocidal properties against molds, which has practical applications, for example, for the prevention of skin mycoses in health and social care facilities.