ISSN:0022-3832    

DOI:10.1002/pol.1954.120120152

出版商:Interscience Publishers, Inc.    

年代:1954

数据来源: WILEY

摘要:

AbstractA method is described for determining the distribution of molecular weights of polyvinylpyrrolidone (P.V.P.) by measurement of the turbidity produced in aqueous solution by varying concentrations of sodium sulfate. Using this method, the acetone‐water method of fractionation is shown to be unsound due to inhomogeneity of the fractions obtained. This latter method is, however, of value in the preparation of P.V.P. of narrow molecular weight ranges by repeated fractionation. The distributions of molecular weights of typical samples of P.V.P. used in the plasma substitute, Plasmosan, are given. Less than 5% by weight of the molecules possess a molecular weight greater than 100,000. The reproducibility and stability to autoclaving of this polymer are shown to be satisfactor

ISSN:0022-3832    

DOI:10.1002/pol.1954.120120153

出版商:Interscience Publishers, Inc.    

年代:1954

数据来源: WILEY

摘要:

AbstractA radial distribution method for interpreting diffuse x‐ray diagrams of liquids has been utilized and further developed for an approach to the solution of structural problems of unoriented specimens of chain polymer substances. The principles of the technique have been given. Experimental distribution curves, indicating the atomic distance distributions have been calculated for the following chain polymers: polyvinyl acetate, polyvinyl alcohol, polystyrene, polyhexamethylene adipamide, polymethyl methacrylate, regenerated cellulose, and alginic acid. For the structure interpretation some of the experimental distribution curves are directly compared with theoretical distribution curves calculated from the atomic distances in measured out structure models, which have been built up on a scale of 1 A. equal to 10 cm. by means of a molecular model building set. From the results obtained, the technique seems to be well suited for structure investigations of unoriented samples of polymer substance

ISSN:0022-3832    

DOI:10.1002/pol.1954.120120154

出版商:Interscience Publishers, Inc.    

年代:1954

数据来源: WILEY

ISSN:0022-3832    

DOI:10.1002/pol.1954.120120155

出版商:Interscience Publishers, Inc.    

年代:1954

数据来源: WILEY

ISSN:0022-3832    

DOI:10.1002/pol.1954.120120101

出版商:Interscience Publishers, Inc.    

年代:1954

数据来源: WILEY