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WATER VAPOUR TRANSMISSION

Water resistance. Coatings must show a negligible absorption of water and must be highly impermeable to water or water-vapour transmission. [Pg.658]

Laminated tapes In more general use now than pressure sensitive tapes are tapes consisting of polyvinyl chloride or polyethylene films in conjunction with butyl rubber. These tapes are applied with an adhesive butyl rubber primer. Thicknesses of up to 0-75 mm are in use and loose protective outer wraps of p.v.c. or polyethylene sheet are commonly applied. Tape quality control is exercised with reference to ASTM standard test methods and may include water vapour transmission rate and elongation. [Pg.666]

ISO 2528, Sheet materials - Determination of water vapour transmission rate -Gravimetric (dish) method, 1995. [Pg.94]

ISO 1663 1999 Rigid cellular plastics - Determination of water vapour transmission properties ISO 2556 1974 Plastics - Determination of the gas transmission rate of films and thin sheets under atmospheric pressure - Manometric method ISO 6179 1998 Rubber, vulcanized or thermoplastic - Rubber sheets and rubber-coated fabrics - Determination of transmission rate of volatile liquids (gravimetric technique)... [Pg.178]

ISO 15106-1 2003 Plastics - Film and sheeting - Determination of water vapour transmission rate - Part 1 Humidity detection sensor method ISO 15106-2 2003 Plastics - Film and sheeting - Determination of water vapour transmission rate - Part 2 Infrared detection sensor method ISO 15106-3 2003 Plastics - Film and sheeting - Determination of water vapour transmission rate - Part 3 Electrolytic detection sensor method... [Pg.178]

A considerable number of alternative techniques have been suggested for measuring vapour permeability of plastics, generally with the aim of making the measurement more convenient and increasing sensitivity. For water vapour transmission, carrier gas type commercial apparatus using an infrared sensor is now commonly used. This procedure is standardised in ASTM... [Pg.359]

Note. For gas permeability the partial gas pressure gradient across the film is 1 atm. For water vapour transmission the humidity gradient is 90%. a Increases with ethylene content. b Decreases with ethylene content. [Pg.214]

Fromder, A. and Lippold, B.C., Water vapour transmission and occlusivity in vivo of lipophilic excipients used in ointments, Int. J. Cosmet. Sci., 15, 113, 1993. [Pg.295]

For flexible film applications such as carrier and trash bags PLA has the potential to replace LDPE and HDPE bags when a compostable solution is desired. Furthermore, the high water vapour transmission rate of PLA is beneficial for fresh food applications where it is important that the water vapour escapes quickly from the packaging. PLA also reduces fogging on the lid of the packaging. [Pg.72]

Several studies reviewed formulations, barrier properties and possible application of edible protein-based films (Table 23.3) (Gennadios et al. 1994 Krochta and Me Hugh 1997 Torres 1994). Overall, similarly to polysaccharide films, proteins exhibit relatively low moisture barrier properties, two to four times lower than conventional polymeric packaging materials (McHugh and Krochta 1994d). The limited resistance of protein films to water vapour transmission is attributed to their substantial hydro-philicity and to the amounts of plasticizers, such as glycerol and sorbitol, incorpo-... [Pg.551]

As compared with their low water absorption, silicone elastomers show an extremely high rate of water vapour transmission. The positive aspect of this property permits one to apply sihcone systems over concrete masonry and other substrates upon which other polymeric coatings blister, crack and peel (Cash, 1970). The negative aspect is that silicone rubber cannot be used as a vapour barrier. The permeabihty to liquids is less compared with that to vapours. [Pg.128]

Banker, G.S. Gore, A.Y. Swarbrick, J. Water vapour transmission properties of applied polymer films. J. Pharm. Pharmacol. 1966,18, 205S-211S. [Pg.1744]

Udeala, O.K. Aly, S.A.S. Degradation kinetics of thiamine hydrochloride in directly compressed tablets. III. Water vapour transmission through free and applied eudragit films. Drug Dev. Ind. Pharm. 1989, 15 (11), 1797-1825. [Pg.1746]

Lindberg NO. Water vapour transmission through free films of hydroxypropyl cellulose. Acta Pharm Suec 1971 8 541-548. Banker G, Peck G, Williams E, et al. Evaluation of hydroxypro-pylcellulose and hydroxypropylmethylcellulose as aqueous based film coatings. Drug Dev Ind Pharm 1981 7 693-716. [Pg.340]

ISO 1663-81 Cellular Plastics — Determination of Water Vapour Transmission Rate of Rigid Materials, 4 pp... [Pg.448]

Moreover, transport phenomena for the sweat case are much more complicated than the water vapour case because wetting of the surface by liquid water precedes water wetting of the surface by liquid water precedes water vapour transmission. Note that there is an important difference in water absorbing characterizing of wool and cotton, although both fibers have relatively high water vapour absorption rates. Because of the hydrophobic surface... [Pg.249]

J. Wehner, B. Miller and L. Rebenfeld, Dynamics of water vapour transmission through fabric barrier, Tex. Res. J., 58(1988) 581. [Pg.268]

Wehner, J. A., Miller, B., and Rebenfeld, L., Dynamics of water vapour transmission through fabric barriers, Textile Res. J. 58, 581-592, 1988. [Pg.270]

Water vapour transmission ASTM C355, BS3177... [Pg.48]

Rate of water vapour transmission E96 ASTM, BS2782-820A/822, DIN 5312L, BS 3177... [Pg.48]

ISO 2528. 1974. Sheet Materials—Determination of Water Vapour Transmission Rate—Dish Method. [Pg.174]

ISO R1195. 1970. Determination of the Water Vapour Transmission Rate of Plastics Film and Thin Sheets. [Pg.174]

Polymer Film thickness (mm) Oxygen transmission rate (cm m day ) Water vapour transmission rate (gm day )... [Pg.453]

The oxygen transmission rates are high since these low crystallinity polymers are above Tg. The water vapour transmission rates are lowest for the metallocene PE of density 905 kg m. BS EN ISO 3826-1 2003 requires the water loss, when a full bag is stored for 42 days at 4 2 °C at 55% relative humidity, must be less than 2%. [Pg.454]

The permeability of the geomembrane samples was calculated using an equation shown below. WVTR(Water Vapour Transmission Rate) measurements were conducted following a procedure detailed in ASTM E 96. [Pg.413]

The permeability measured by water vapour transmission rate is given in Table 4. It is seen that HOPE showed a superiority among other materials, PVC geomembrane was the worst in permeability among the samples tested. Bitumen contents adversely affect the permeability of ECB. [Pg.417]

Queen, D., Gaylor, J.D.S., Evans, J.H., Courtney, J.M., Reid, W.H. The precltntcal evaluation of the water vapour transmission rate through birm woimd dressings. Biomaterials 8, 367-371 (1987)... [Pg.251]

See other pages where WATER VAPOUR TRANSMISSION is mentioned: [Pg.369]    [Pg.469]    [Pg.770]    [Pg.165]    [Pg.299]    [Pg.214]    [Pg.2038]    [Pg.305]    [Pg.149]    [Pg.369]    [Pg.469]    [Pg.41]    [Pg.240]    [Pg.143]    [Pg.194]    [Pg.308]    [Pg.5]    [Pg.411]    [Pg.5]    [Pg.262]   
See also in sourсe #XX -- [ Pg.38 ]

See also in sourсe #XX -- [ Pg.46 , Pg.47 , Pg.50 ]

See also in sourсe #XX -- [ Pg.102 ]



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