The Additive Action of Adsorbed Films

In this section we shall start with an examination of lubrication behavior under conditions in which the existence of an adsorbed film and the nature of its properties are known positively. The information so obtained will then be applied to discussions of experiments carried out under less rigorous control. 

There are some complicating factors, notably temperature. Stearic acid vapor reacts with activated aluminum oxide to form an aluminum stearate which is tenaciously retained by the adsorbent. On raising the temperature of the system, the desorbed material is not stearic acid but decarboxylated, cracked olefinic hydrocarbons. 

Frictional behavior during the course of a traverse over a condensed monolayer of n-hexadecylamine hydrochloride was similar to that for the quaternary ammonium bromide except, as expected from Fig. 10-9, the film of primary amine hydrochloride was more durable. 

TABLE 10-7. DURABILITY OF FILMS RETRACTED FROM SOLUTIONS OF n-DOCOSYLAMINE IN n-HEXADECANE 

Load 49.03 N. fivij/ANp changes from 0.0036 to 0.027 after the 12th 

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