Barrier textiles

Wehner, J. A., Miller, B., and Rebenfeld, L., Dynamics of water vapour transmission through fabric barriers, Textile Res. J. 58, 581-592, 1988. 

Finally, PCMs [20] are becoming increasingly popular in improving comfort properties in barrier textiles such as protective or medical textiles against particles and liquids (e.g., blood) that can carry infection. Microencapsulated fibers or coat-... 

Some cast (unoriented) polypropylene film is produced. Its clarity and heat sealabiUty make it ideal for textile packaging and overwrap. The use of copolymers with ethylene improves low temperature impact, which is the primary problem with unoriented PP film. Orientation improves the clarity and stiffness of polypropylene film, and dramatically increases low temperature impact strength. BOPP film, however, is not readily heat-sealed and so is coextmded or coated with resins with lower melting points than the polypropylene shrinkage temperature. These layers may also provide improved barrier properties. 

In fine wool such as that obtained from merino sheep, the cuticle is normally one cell thick (20 x 30 x 0.5 mm, approximate dimensions) and usually constitutes about 10% by weight of the total fiber. Sections of cuticle cells show an internal series of laminations (Figs. 1 and 2) comprising outer sulfur-rich bands known as the exocuticle and inner regions of lower sulfur content called the endocuticle (13). On the exposed surface of cuticle cells, a membrane-like proteinaceous band (epicuticle) and a unique hpid component form a hydrophobic resistant barrier (14). These hpid and protein components are the functional moieties of the fiber surface and are important in fiber protection and textile processing (15). 

Poly(trimethylene terephthalate) (PTT) is a polymer with very useful properties. As a textile fibre it has excellent softness, stretch and recovery. As a resin it has excellent barrier properties. Developed over 60 years ago, PTT has not been very widely used compared to poly(ethylene terephthalate) (PET) as one of the key monomers 1,3-propanediol (PDO) has been expensive. 

Crowse, J.L., Dejonge, J.O., and Calogero, F. (1990) Pesticide barrier performance of selected nonwoven fabrics in laboratory capillary and pressure penetration testing, Textile Research., 60 137-142. 

Bags, textile bags, mattress bags, boiling bags. Good moisture barriers... 

Dr. A. Shaw at the University of Maryland Eastern Shore in Princess Anne, Maryland, is evaluating textile substrate for pesticide barrier effectiveness and comfort. Tests will be conducted to assess effectiveness of decontamination processes for these personal protection devices. Diazinon emulsifiable concentrates will be used to contaminate fabrics. Simulated wear studies will be conducted in the laboratory to assess the efficacy of these fabrics in protecting human health. 

Jickins R.S., Leonas K.K., Influence of a polyethylene glycol treatment on surface, hquid barrier and antibacterial properties Textile Chemist Colorist, 26 (12) (1994) 25-29. 

Van Hees P, Axelsson J. Modelling of euroclass test results by means of the cone calorimeter. In Multifunctional Barriers for Flexible Structure Textile, Leather, and Paper. Duquesne S, Magniez C, Camino G, Eds. Springer Berlin, 2007. 

ASTM D 7140 Standard Test Method to Measure Heat Transfer through Textile Thermal Barrier... 

If the textile is not to hang freely, it is then mounted on a strainer which has a washed cotton fabric stretched very tightly over it. The textile is sewn and mended down to this mounting fabric and then enclosed in a 3-sided Plexiglas box, making sure the Plexiglas does not touch the textile. The back of the strainer is covered with a washed cotton flannel, which allows the textile to breathe but still acts as a dust and moisture barrier. 

Synthetic polymers are also a major contributor in the textile industry. Synthetic fibers show excellent strength properties, chemical resistance, wrinkle resistance, and abrasion resistance. These fibers also show some undesired properties such as hydrophobicity due to which they show wearing discomfort as perspiration cannot penetrate the fabric and lower the reactivity with chemical agents, which normally act as barrier to other finishing agents. These problems are due to the presence of hydrophobic groups on the surface of synthetic polymers. Therefore, surface modification of synthetic polymers is very necessary. 

Biological methylation of antimony has not been demonstrated directly by use of experimental organisms. However, methylstibonic acid and dimethylstibinic add were found in fact in marine and estuarine environment . There is no obvious thermodynamic barrier to biomethylation. The chemical similarity between Sb and Sn, Pb, As, Se and Te, which surround Sb in the periodic table, and all of which have been shown to be subject to biomethylation, would suggest the existence of a biomethylation pathway also for antimony. This possibility assumes importance when the current extensive use ca 2 X lO kgy" in United State and ca lO kgy in Japan) of inorganic and organic antimony compounds in conjunction with halocarbons in fire retardant systems is considered. Products containing antimony-hased fire retardant systems include textiles, plastics, elastomers, paper, wood, paints and coatings. ... 

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