ISSN:
0022-3832
Schlagwort(e):
Chemistry
;
Polymer and Materials Science
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
,
Physik
Notizen:
The influence of water vapor on the rate of diffusion of organic molecules has been studied at 40°C. by the sorption method for the systems water-acetone-polyvinyl acetate, water-carbon tetrachloride-polyvinyl acetate, water-acetone-cellulose acetate (37.9% acetyl) and water-benzene-polystyrene. For the first three systems the rate of diffusion of the organic vapor is markedly faster for the mixture of water and organic vapor than for the pure organic vapor. With polyvinyl acetate, the rate of diffusion of 80 mm. of acetone is increased about 25-fold if 36 mm. of water vapor is mixed with the acetone. Diffusion of the larger carbon tetrachloride molecule is accelerated by water even more than is acetone. Water vapor at a pressure of 36 mm. causes about a 30-fold increase in the rate of diffusion of 80 mm. of acetone into cellulose acetate even though the diffusion of acetone itself into cellulose acetate is anomalous. With polystyrene the presence of water vapor causes no acceleration of the diffusion of benzene which is the expected result since, in contrast to the other two polymers, polystyrene sorbs only very small amounts of water. It is concluded that the marked effect of water vapor on the diffusion of organic vapors into polyvinyl acetate and cellulose acetate involves (a) a rapid diffusion of water into the polymer and (b) more rapid diffusion of the organic vapor into the “water plasticized” polymer than into the dry polymer.
Zusätzliches Material:
3 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/pol.1954.120147601
Permalink
