ISSN:
0360-6376
Keywords:
Physics
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
N,N′-Dicaproyl (-)1,2-diaminopropane (I) was used as a convenient model for the study of the optical activity of a nylon type polyamide: polysebacamide (-)1,2-diaminopropane (II). ORD of I was measured in different solvents. A peculiar behavior is observed in methanol in the presence of mineral salts. The influence of 0.1M potassium salts (Cl-, Br-, SCN-, NO3-, SO4-2) and 0.1M alkaline chlorides and alkaline earth chloride hexahydrates on the optical activity of I in methanol are described. Alkaline salts and MgCl2 give approximately the same effect: there is a decrease of the rotations without change of sign. SrCl2 and CaCl2 shift ORD curves towards the negative rotations, the last one giving complete inversion. This inversion is directly related to the CaCl2 concentration and is attributed to adduct formation between amide groups and salt. Assuming that the different species are at equilibrium, an apparent equilibrium constant is obtained from the optical rotations for a complex of one mole of CaCl2 with one mole of I. Results are used to discuss the complex ORD of poly(-) 1,2-diaminopropane sebacamide in methanol saturated with CaCl2.
Additional Material:
8 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pol.1974.170120415
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