Friction properties of chemically modified starch

Abstract

Starches of varying chemical structures were esterifi ed with anhydrides, formulated into dry fi lm lubricants with the addition of canola oil, and its friction properties investigated. In the absence of canola, chemically modifi ed starch displayed a very high coeffi cient 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 the further increase in [canola]. This observation was attributed to the adsorption of the canola oil onto starch due to H-bonding between the ester groups of the canola triglycerides and the free hydroxyl groups of starch. Analysis of the [canola] vs COF data using the Langmuir adsorption model showed stronger adsorption of canola to modifi ed starch with a lower degree of substitution (DS). This was attributed to the availability of more free hydroxyl group adsorption sites on starches with lower DS than those with higher DS.

A review of recent advances and applications of machine learning in tribology

“…Chemically modified starch contains free hydroxyl groups which increases the polarity of the surface and thereby its CoF. 366 Addition of canola oil to chemically modified starch interacts with the free hydroxyl groups of starch and thereby decreases the CoF. 366,367 Overall applications of glycomaterials are yet to be fully explored and glycomaterials, in general, show a lot of promise of becoming the lubricants of the next generation due to their abundant availability and bio-degradability.…”

“…366 Addition of canola oil to chemically modified starch interacts with the free hydroxyl groups of starch and thereby decreases the CoF. 366,367 Overall applications of glycomaterials are yet to be fully explored and glycomaterials, in general, show a lot of promise of becoming the lubricants of the next generation due to their abundant availability and bio-degradability. Thus, it is necessary to focus in this direction as heavy use of environmentally hazardous materials is a threat to nature.…”

Chemical transformations of renewable lubricant feedstocks

“…6.53) to improve their water solubility [362]. The chemically modifi ed starches were then dissolved in water and formulated into dry-fi lm lubricants by incorporation of canola oil.…”

Usage of Starch in Leather Making

“…The degree of polymerization of starch is about 160 to 6000, and its relative molecular weight is about 25000 to 1000000 (Lu et al, 2005). It should be noted that the molecular structure (linear or branched) and molecular weight of starch molecules in a crop have a significant influence on its processability for various applications (Biresaw and Shogren, 2008).…”