Abstract
The substitution effects of α-alkyl chain on the physical properties of fatty acid and sodium salt were studied.
The introduction of alkyl chain into α-position brought about a depression of melting point of fatty acid, a depression of Krafft point, an expansion of area per molecule and a decrease of c.m.c. of its sodium salt.
These substitution effects of α-alkyl chain increased as the carbon number of α-alkyl chain increased and with decrease of main alkyl chain.
In the case of c.m.c., there existed linearity between the carbon number of α-alkyl chain and logarism of c.m.c., it was therefore found from calculation that one carbon of α-alkyl chain corresponded with 0.3 to 0.4 carbon of main alkyl chain.
