Results 211 to 220 of about 88,197 (238)

Water-vapor permeability of polyvinyl alcohol films

Desalination, 1987
Abstract The water-vapor permeability ( P v ) and the rate of water-vapor transmission ( Q v ) for PVA films were determined at three temperatures (20, 38 and 60°C) and three relative humidities (50, 70 and 90%) by the cup method using a controlled humidity test cabinet.
Yu Xianda, Wang Anlai, Cao Suqin
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Water vapor permeability of biodegradable polymers

Journal of environmental polymer degradation, 1997
The water vapor transmission rates (WVTR) of several biodegradable polymers were evaluated to determine their suitability as water-resistant coatings and to understand WVTR better in terms of polymer structure. Values of WVTR at 25‡C ranged from 13 to 2900 g/m2 /day and increased in the order PHBV PLA (cryst.) PLA (amorph.) PCL Bionolle BAK 1095 CAP CA.
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Water vapor permeability of ultrathin polyurethan films

Journal of Macromolecular Science, Part B, 1969
Abstract Measurements were made on the flux of water through unsupported polyurethan thin films ranging jn thickness from 0.7 to 275 μ (11 mils), using cup cells under the conditions of water in contact on the inside film surface and 45% or 35% relative humidity outside.
Nathaniel S. Schneider, Alfred L. Allen, Louise V. Dusablon   +2 more
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Water Vapor Permeability

1999
Materials which are able to take in or let out moisture either need to be porous or selectively permeable. Membranes are products which are permeable to low molecular weight products or ions. In this work we will discuss mainly microporous or hydrophilic films, coatings and impregnations, i.e. materials permeable to water vapor.
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Water Vapor Permeability of Edible Bilayer Films

Journal of Food Science, 1984
ABSTRACT Edible films composed of a water soluble, carbohydrate layer (hydroxypropyl methylcellulose) and various kinds of lipid layers were tested for resistance to water vapor permeability. Films were tested at 25°C and a relative humidity differential of 85%.
S. L. KAMPER, O. FENNEMA
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The permeability of membranes to water vapor

Desalination, 1967
Abstract The aim is to establish, for a given membrane, a curve showing the permeability to water vapor in relation to the temperature. Evaporation is effected in a thermostatized cell. The membrane to be tested lies on distilled water. Air having the same temperature as the distilled water, but entirely dried, circulates above the membrane at a ...
A. Van Haute, Y. Henderyckx
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Permeability of water and water vapor through cellulosic membranes

Journal of Applied Polymer Science, 1975
To elucidate the water transport mechanism through homogeneous membranes, water and water vapor permeation through crosslinked cellulose membranes, cellulose diacetate, and cellulose triacetate membranes are studied. It is found that the water flux increases with the degree of hydration; and as for cellulose membranes, the degree of hydration is an ...
M. Kawaguchi, T. Taniguchi, K. Tochigi, A. Takizawa   +3 more
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A New High Water Vapor Permeable Polyetherurethane Film Dressing

Journal of Biomaterials Applications, 1990
This study summarizes the Ph.D.-research project concerning the development of a new high water vapor permeable wound dressing. The dressing is composed of a 15 μm thin polyetherurethane (PEU) film, which has many non-interconnected cavities to enable a high water vapor permeability up to 20.1 g · m−2 · h−1 · kPa−1.
M F, Jonkman, P, Bruin
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Conversion of Water Vapor Permeable Products

1999
There are processing techniques specific for leather substitutes. In contrast to leather, man-made leather can be processed in a continuous manner. Thermoplastic conditions are often used to form the surface to a grain pattern or gloss in a continuous process [14].
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The Permeability of Rubber to Water Vapor

Rubber Chemistry and Technology, 1943
Abstract In connection with a study of various kinds of vulcanized rubber, including rubber films from vulcanized latex and latex films vulcanized in the dry state, it seemed desirable to investigate the packing of the latex particles. To what extent, for example, are these still present or are they coalesced?
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