Technical Abstract: Starch is a high molecular weight polyglucose biopolymer that, in its native state, is insoluble in water at room temperature. One way of improving its water solubility is by esterification of its free hydroxyl groups. Waxy maize, normal corn, and high amylose corn starches were esterified with acetic anhydride (AA). Waxy maize starch was also esterified by a mixture of AA and either octylsuccinic anhydride or dodecylsuccinic anhydride. The resulting chemically modified starches, with varying degrees of substitution (DS) of the hydroxyl groups, were dissolved in water, formulated into dry film lubricants with the addition of canola oil, spray applied onto clean sheet metals, and its friction properties investigated. The results showed that, in the absence of canola, chemically modified starch displayed very high coefficient of friction (COF). Addition of canola resulted in a sharp decrease in COF, which decreased with increasing canola until it attained a minimum and constant value that was independent of further increase in canola. This observation was attributed to adsorption of the canola onto starch due to H-bonding between the ester groups of the canola triglycerides and free hydroxyl groups of starch. Analysis of the canola vs. COF data using the Langmuir adsorption model showed stronger adsorption of canola to modified starch with lower DS, which was attributed to the availability of more free hydroxyl group adsorption sites on starches with lower DS than those with higher DS.