and Miss Jean Thomas of the University of Wisconsin for further details concerning construction and manipulation of their optical system and diffusion cell. Our thanks are also due to Mr. Stanley Cassid, instrument maker, for many helpful suggestions and for his careful construction of our diffusion cell. SummaryThe diffusion coefficient of sucrose in highly concentrated and supersaturated solutions has been measured at 25 and 35' by two optical methods, the usual schlieren method and the new Gouy interference-fringe method. The latter 1. method gave more accurate results from the standpoint of internal consistency and on an absolute basis also, we believe.2. 3.A new diffusion cell is described. The diffusion coefficients decrease linearly with increase in weight per cent. of sucrose extrapolating to zero a t 81% sugar a t both temperatures, but they are all higher by 5-10 fold than diffusion coefficients calculated from Gordon's equation. We believe this to be due to a possible difference in mechanism between the viscous flow and diffusion processes as the solution becomes highly concentrated.The hydrolysis of lactones to give hydroxy acids is usually considered to be a typical case of ester hydrolysis. This appears to be valid for y-lactones which give the expected hydroxide ion and acid catalyzed reactions. However with plactones an added reaction with water enters2 With @-butyrolactone Olson and co-workers3~ have shown that the hydrolysis in basic and in strongly acid solutions results in the expected acyl-oxygen fission and retention of configuration of the @-carbon. However, in the pH range of from 1 to 7 the only observable reaetion is a pH independent hydrolysis which splits the alkyloxygen bond and inverts the configuration of the @-carbon.Since Olson and co-workers were primarily interested in the mechanisms of the hydrolysis of 6-butyrolactone they did not investigate the kinetics very fully. This is particularly true of the acid catalyzed reaction. Consequently we have investigated the hydrolysis of the related ppropiolactone in acid, basic and neutral solutions with emphasis on the temperature coefficients of the reactions and on the kinetics of the acid catalyzed reaction. The reactions of /3-propiolactone with hydroxide ion and water have been studied at 25' by Johansson2; the acid catalyzed hydrolysis has not been previously investigated.Materials and Procedures.-The p-propiolactone used in these studies was obtained from the B. F. Goodrich Chemical Cqmpany. I t was stored at 5" and from 30 to 50 ml. were redistilled a t reduced pressure from time to time. Its freezing point was found to be -33.4'.Its equivalent weight was determined by addition of excess base (1) Presented in part a t the 116th meeting of t h e American Chemi-(:' ) Johansson, Chein.and back titration with acid and was found to be 71.93, indicating a purity of 99.8% or better.Since the @-propiolactone has a marked tendency to p~lymerize,~ preliminary tests were made to see if this would complicate the hydrolysis experiments. It wa...
The retention of individual fatty soils, in both the presence and absence of clay soil, on repeatedly soiled, aged, and washed unfinished Dacron/cotton blend was studied by means of a double-label radioactive tracer analysis. Fatty soil retention was influenced by unsaturation, polarity and chain length, but the presence of clay soil was not a significant factor under the experimental conditions employed. Fabric yellowing was measured on samples soiled with clay and pairs of fatty soils and on appropriate controls. None of the organic soils caused observable yellowing in the absence of clay. While clay soil alone contributed significantly to residual yellowness, additional yellowing occurred on samples soiled with clay, oleic acid, and triolein. It was hy pothesized that the yellowing behavior observed when clay, oleic acid and triolein were present was due primarily to the embedding of pigmented particulate soil in a polymerized fatty film during the second clay soiling process.
A double-label radioactive tracer analysis was developed to determine the comparative retention of representative sebum components on cotton fabric after repeated soiling and laundering and to determine whether the presence or absence of clay significantly affected the retention of the fats. Retention was related to chain length, polarity, unsaturation, and presence of clay.The yellowness of cotton soiled with pairs of fats was measured in the presence and absence of clay. Clay contributed significantly to the yellow color. When fat alone was present, there was no significant increase in yellowing until after the fifth wash for oleic acid and triolein. An interaction between the fats and clay caused additional yellowing which was possibly due to greater uptake of clay by entrapment in a fatty matrix and/or to catalysis of oxidation reactions of unsaturated fats by metal ions present in kaolinite clay. ' I ABSTRACT Tumble-drying techniques similar to those which might be encountered in home laundering are investigated. The effects of fabric dimensions and aesthetic softness and limpness are studied, and a tentative explanation of the aesthetic changes in terms of observed physical differences is offered.
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