Refine
Document Type
- Journal article (13)
Has full text
- no (13) (remove)
Is part of the Bibliography
- yes (13)
Institute
- Texoversum (13)
Publisher
Abreinigbare Schlauchfilter kommen zur Abscheidung von Stäuben sowie staubförmigen Substanzen zum Einsatz. Aufgrund typischer Prozessbedingungen unterliegen sie während ihres Einsatzes thermischer, chemischer und mechanischer Beanspruchung. Das IGF-Projekt Nr. 18307 "Untersuchung der chemischen und thermischen Degradation von abreinigbaren Filtermedien und Verbesserung deren Beständigkeit durch Oberflächenmodifikation" hat mehrere Prüfmethoden verglichen.
The pH value of the human skin is not in the neutral range but is slightly acidic with values of – depending on the body part – 3.5 to 6. This provides a suitable habitat for the commensal skin floral but has a killing effect on some pathogenic micro-organisms and an inactivating effect on some viruses. This protective acid mantle of the skin thus represents a first external protective layer against infestation by pathogens. An appropriate surface pH on textiles can help to minimize the transmission of pathogens through the clothing of healthcare workers while at the same time not exerting a negative influence on the skin’s own flora. In addition, the colonization of e.g. bed linen by pathogenic microorganisms can be reduced. This can also have a positive influence on bacteria-associated odor formation on functional clothing.
The pH value of the human skin is not in the neutral range but is slightly acidic with values of – depending on the body part – 3.5 to 6. This provides a suitable habitat for the commensal skin floral but has a killing effect on some pathogenic micro-organisms and an inactivating effect on some viruses. This protective acid mantle of the skin thus represents a first external protective layer against infestation by pathogens. An appropriate surface pH on textiles can help to minimize the transmission of pathogens through the clothing of healthcare workers while at the same time not exerting a negative influence on the skin’s own flora. In addition, the colonization of e.g. bed linen by pathogenic microorganisms can be reduced. This can also have a positive influence on bacteria-associated odor formation on functional clothing.
Cleanable bag filter : comparisons of different testing methods of ageing of filter materials
(2019)
Cleanable bag filters are used to separate dust and other airborne particulate systems. Due to typical process conditions, they are subject to thermal, chemical and mechanical stress during use. The main objective of the IGF project no. 18307 "Investigation of the chemical and thermal degradation of cleanable filter media and improvement of their resistance by surface modification", was the development of a valid test method which can reproduce degradation caused by high temperatures and aggressive chemical atmospheres in a practice-oriented but time-saving manner. Within the IGF project, 2 accelerated ageing methods were applied, both of which have the decisive advantage of investigating damage in the gas phase. Many resistances of filter materials are otherwise carried out by immersing the materials in a mostly liquid damage medium at a defined temperature. These resistances are difficult to transfer ageing in the gas phase.
Protective welding clothing must meet various requirements. Among other things, it must be flame-resistant, protect against splashes of metal or sparks and also ensure protection against radiant heat and UV light caused by exposure to the welding arc. The protection against molten metal splashes is directly related to the fabric weight per unit area of the protective welding clothing and the level of protection is normally determined by the number of molten metal droplets that fall on the fabric. The higher the weight per unit area, the greater the protection against welding spatter. However, increasing the fabric weight per unit area also leads to psychologically uncomfortable wearing and thus increasing the physical strain on the wearer. The required basis weight per unit area of protective welding clothing can be reduced by applying nanoparticles as a protective layer while preserving other indispensable properties.
Schweißerschutzkleidung muss unterschiedlichen Anforderungen genügen. Sie muss u.a. flammfest sein, den Schweißer vor Metallspritzern schützen, die beim Schweißen entstehen, und auch einen Schutz vor UV-Licht sicherstellen, das im Schweißbogen entsteht. Besonders der Schutz vor Metallspritzern wird durch das Flächengewicht der Textilien bestimmt. Der entsprechende Schutzfaktor wird durch Tropfen flüssigen Eisens bestimmt, die auf ein Gewebe fallen. Dabei gilt: je höher das Flächengewicht, desto höher der Schutz vor Schweißspritzern. Jedoch gilt auch: je höher das Flächengewicht, desto schlechter ist der Tragekomfort und desto wärmender ist die Kleidung und damit die körperliche Belastung des Trägers. Durch die Applikation von Nanopartikeln ist es möglich, das benötigte Flächengewicht der Kleidung zu reduzieren.
Im Zuge von REACH wurden gängige hocheffektive halogenierte Flammschutzmittel verboten, da diese unter dem Verdach stehen, kanzerogen, mutagen und teratogen zu sein. Zur Zeit fehlen entsprechende Alternativen. Daher werden am DTNW neue umweltfreundliche und halogenfreie Flammschutzmittel auf der Basis von Phosphor- und Stickstoffverbindungen entwickelt, um einen entsprechenden Flammschutz zu gewährleisten. Neue Möglichkeiten werden im Rahmen dieses Artikels vorgestellt.
Es wird eine Möglichkeit zur Quantifizierung der Schädigung von Geweben bei der Martindale-Flachscheuerung vorgestellt, die eine interessante Möglichkeit darstellt, vergleichende Untersuchungen durchzuführen, auch wenn die Gewebe nicht bis zu einem Fadenbruch gescheuert werden. Die Untersuchungen deuten außerdem eine Skalierbarkeit der Scheuerversuche bei unterschiedlichen Anpressdrücken an. Sollte sich diese Beobachtung in weiteren Untersuchungen bestätigen, würde dies eine grundlegende Vereinfachung der Scheuerprüfung für verschiedene Anwendungen bedeuten.
Using the damage area as a quantification method for the Martindale test is a promising method to compare textile finishes without the need to test to full destruction. In addition, it could be shown that the results of Martindale tests performed with different pressure loads can be scaled to identical functional shape. If these results can be verified, this method would be a simplification of abrasive testing for different application areas.
In the IGF project No. 19617 N, nitrogen and phosphorous substituted alkoxysilanes were prepared and their ability to inhibit fire growth and spread for fabrics was explored. To this end, a series of flame retardants were synthesized using different strategies including click chemistry and nucleophilic substitution of commercial organophosphorus compounds with amino-based trialkoxysilanes and/or cyanuric chloride. The new halogen-free and aldehyde-free flame retardants were applied to different fabrics such as cotton (CO), polyethylene terephthalate (PET), polyamide (PA) and their blends using the well-known pad-dry-cure technique and sol-gel method. The flame-retarding efficiencies were evaluated by EN ISO 15025 test methods (protective clothing-protection against heat and flame method of test for limited flame spread). Good flame retardancy of the hybrid organic-inorganic materials was achieved with the addition of as small amount as 3-5 wt.% for cotton fabrics. Moreover, the water solubility and the washing resistance could be controlled through the functional groups attached to the phosphor atom or through the optimization of the curing temperature. Overall, the research project demonstrated that N-P-silanes are very good permanent flame retardants for textiles.