ISSN:0022-3832    

DOI:10.1002/pol.1948.120030111

出版商:Interscience Publishers, Inc.    

年代:1948

数据来源: WILEY

摘要:

AbstractA study has been made of the swelling characteristics of Styrene‐divinylbenzene gels containing from 0.02 to 0.12% of the cross‐linking agent. Variation in swelling of samples containing the same amount of divinylbenzene was shown to increase with decreasing divinylbenzene concentration. The influence of amount of cross‐linking agent, type of solvent, and temperature, on equilibrium swelling is reported. By assuming that μgis 0.44 for polymer‐toluene, values of μgfor over 50 different solvents have been obtained. No values of μgbelow 0.42 were found. A correlation of swelling values and of μgvalues with cohesive energy densities of the solvents is presented. The polymer appears to have a cohesive energy density of 82 cal. per cc. Equilibrium swelling decreases slightly in toluene and methyl ethyl ketone but increases markedly in cyclohexane with rising temperature. Efforts to calculate gel constants from the temperature coefficient of swelling failed completely in the case of cyclohexane, and were only moderately successful with toluene. These temperature studies, and the cohesive energy density correlations both appear to indicate a lack of complete understanding about the physical significance of μ, and why it depends so markedly on c

ISSN:0022-3832    

DOI:10.1002/pol.1948.120030112

出版商:Interscience Publishers, Inc.    

年代:1948

数据来源: WILEY

摘要:

AbstractThe German redox system of emulsion polymerization of butadiene and styrene has been found to be very sensitive to exact details of experimental procedure. Soap may be substituted for the alkanesulfonate used by the Germans; it is then unnecessary to add ferric laurate to the system.Careful investigation of the soap‐emulsified mixture leads to the conclusion that 0.25 parts of benzoyl peroxide, 0.50 parts of ferrous sulfate heptahydrate, and 3.0 parts of sodium pyrophosphate decahydrate were the optimum concentrations of the essential ingredients for polymerization of an emulsion of 75 parts of butadiene and 25 parts of styrene in 200 parts of water and 5 parts of Procter and Gamble soap Flakes (S.F.) at 30°. At very low iron concentration the addition of a reducing agent as “booster” was beneficial; for this purpose sorbose can be replaced by fructose or, less satisfactorily, by a number of other reducing

ISSN:0022-3832    

DOI:10.1002/pol.1948.120030113

出版商:Interscience Publishers, Inc.    

年代:1948

数据来源: WILEY

摘要:

AbstractCrystalline soybean trypsin inhibitor has been inactivated by ultraviolet light (λ2537 Å.) with a quantum yield of 0.0088 based upton loss of ability to inhibit the action of trypsin on casein. Inactivation involves a “one‐hit”

ISSN:0022-3832    

DOI:10.1002/pol.1948.120030114

出版商:Interscience Publishers, Inc.    

年代:1948

数据来源: WILEY

ISSN:0022-3832    

DOI:10.1002/pol.1948.120030115

出版商:Interscience Publishers, Inc.    

年代:1948

数据来源: WILEY

ISSN:0022-3832    

DOI:10.1002/pol.1948.120030117

出版商:Interscience Publishers, Inc.    

年代:1948

数据来源: WILEY

ISSN:0022-3832    

DOI:10.1002/pol.1948.120030118

出版商:Interscience Publishers, Inc.    

年代:1948

数据来源: WILEY