Breathable structures

Hydrophilic PEBAX resins with polyethylene glycol (PEG) ether structural units allow water vapor to go through compact films at a high rate while being water-proof. These films are permeable to other gases, such as CO2, O2, N2, and C2H4. 

---

Figure 16.15 Superhydrophobic surfaces in biology the lichen Lecanora conizaeoides showing high roughness with inset showing water drop 155 4°. (Reprinted with permission from Journal of Plant Physiology, A lichen protected by a super-hydrophobic and breathable structure by N.J. Shirtcliffe, F. B. Pyatt, M.l. Newton and C. McHale, 163, 1193-1197. Copyright (2006) Elsevier Ltd)...

The benefits of using TDDS include the improvement of systemic bioavait-ability, as a result of bypassing the first pass metabolism. Variables due to oral administration, such as pH, the presence of food or enzymes and transit times can all be eliminated. TDDSs also allow for fast interruption of the treatment in the case of any adverse effects. Textile materials are often permeable, comfortable, aesthetic, breathable structures, which are also easy to use, and can usually be treated to improve their absorptive capacity. 

The concept of looking across specific laws and regulations to the underlying operations of the business is the preferable way to structure a compliance system. Because TSCA is not specific to any one environmental medium, a thorough and well-designed TSCA audit should look at all the environmental media. For example, the EPA can use TSCA to regulate the release to water of a specific chemical, or its presence as breathable particles in the workplace, or its method of disposal. In those circumstances an audit should investigate all of the pertinent media. 

Elimination of seams from the shoe upper and ability to seamlessly incorporate various knitted structures into the upper piece offer added flexibility, reduced weight, foot conformity and mapping of the upper part of the foot, according to the required support and flexibility, as well as to the thermo-physiological requirements of the foot such as ventilation, thermal transfer and breathability. It is also possible, similarly to the garment circular machines described above, to vary the stitch length of the knitted... 

The main property of the outer shell is to provide a protection against the outside weather conditions, mainly rain, snow and wind. In order to avoid excessive sweat accumulation, the outer layer should allow moisture transfer from the body to the environment. Such waterproof, windproof and breathable fabrics (WBF—mainly membranes and coatings) have been on the market for more than 30 years. The waterproof properties and, at the same time, the water vapour transfer are either achieved with a micro-porous or a hydrophilic structure, or a combination of both technologies (bi-component WBF). Waterproofness and breathability are contradictory requirements and, therefore, a compromise has to be found between protection and comfort properties. This compromise is usually achieved by adapting the porosity and thickness of such WBF layers. 

Of great significance when technical textiles are used in contact with the human body are aspects such as moisture transport and breathability, as described in Chapters 2 (waterproof breathable fabrics), 5 (medical textiles), 9 (personal thermal protection) and 10 (survival). Medical textiles (Chapter 5), which has been a particular growth area in recent years, demonstrates the need for novel fibres, fabric structures and treatments that are revolutionising chnical science. 

Finally, the question remains whether the stability, especially shear stability, suffers from the significantly improved breathability and dimensional stability provided with these new additives. Examination of cellular structures of the machine mixed free rise chicken bucket... 

Development of a wearable, self-powered early warning system for breast cancer will require the production of textile structures that are flexible, comfortable, breathable, ligbt, and suitable for integration with the materials developed to perform various functions to operate the cancer detecting devices produced. 

This coextrusion techniqne has been applied to the fabrication of breathable films, using polyethylene oxide and polyolefin fiUed with CaC03. As the layer thickness decreased, the water vapor transmission rate changed dramatically due to changes from a continuous to discontinuous layer structure. Microlayer extrusion of a number of polymers has been accomphshed, including combinations of high-density polyethylene (HDPE) and linear low-density polyethylene (LLDPE), ethylene-styrene copolymers and low-den-... 

The fiber is composed of about 90% cellulose and about 6% moisture and the rest as natural impurities. Each fiber is a single elongated cell that is generally fiat, twisted, and has a ribbon-like structure. The fiber has a wide inner hollow. The outer surface of the fiber is covered with a protective wax like coating, giving the fiber an adhesive like quality. Cotton fiber can be easily spinned into a yam. The biodegradability, softness, absorbency, and breathability make them useful in fabrics. 

Moreover, SRG is breathable, can be used as a hydraulic binder-based matrix, and features a high permeability. The application of these materials does not alter the original behavior of the structure in any way and allows to preserve the water content in the wall within the natural Umit of variability of the structure. These advantages make the structures strengthened this way particularly compatible with masonry structures, thus they become more compliant and are welcomed by the Superintendence for the Architectural and Landscape Heritage. 

Reinforced masonry breathability Increase of the structure ductility Easy modeling of materials Lack of oxidation phenomena Higher durability of the structure No increase in weight of the structure Rapidity of application... 

The microfiber structure of the melt-blown web provides excellent barrier and breathability properties, which are required in this market segment. It is dominated by composite fabrics (mainly S/M/S), because, for example, surgical gowns need to be strong, breathable and barrier resistent. 

---