We have determined the critical micellar concentration (c.m.c) of the derivates type piperidinoethyl esters 3-alkoxy phenylcarbamic in the medium 0.05 moUl and 0.2/moUl NaCI for using spectrophotometry methods in the UV region of the spectrum at temperature T=25 °C and pH=4.5-5.0. We found the parabolic dependence of the -ln(c.m.c.) on the (n) number of the carbon in the alkoxy substituent chain. Further, we have observed the facility formation of the micelle at the solution of 0.2 moUl than 0.05 moUl NaCI.

        Key words: piperidinoethyl esters 3-alkoxysubstituented of phenylcarbamic acid - critical micellar concentration (c.m.c.)