Submitted to: American Chemical Society National Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 8/26/1999
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: Rapid depletion of the world's crude reserve has posed a serious concern among developed and developing countries alike. An increasing concern for environmental safety due to the non-biodegradable nature of mineral basestocks has resulted in a search for alternative sources of fuel. Being a tangible and reliable source of basestock, vegetable oil and other vegetable-based functional fluids have seen a quite promising increase in use as biodegradable lubricants over the last decade. Due to various techno-economical disadvantages, vegetable oils are not in widespread usage. In terms of chemical structure, vegetable oils are different from mineral base oils and in several areas have distinct disadvantages in performance, the most serious being poor oxidative stability and low temp. behavior. This results in increased acidity, corrosion, and viscosity of the base fluid. The advantages are mainly biodegradable, low volatility, good lubricity, and additive miscibility. Current research endeavors are directed towards improving the oxidative and low temp. properties of vegetable oils. A combination of thin film micro oxidation, PDSC, NMR, SEM, and low temp. studies were carried out on a series of vegetable oils and their oxidation products, including nature and type of insoluble deposits and low temp. behavior. Important structural parameters of the triglyceride molecule were identified that influenced oxidative and low temp. behavior. Chemical modification of the fatty acid chain structure was thought of as an alternative approach to affect the main functional properties (i.e. oxidative and low temp. behavior) without affecting the triglyceride backbone structure, thereby retaining excellent biodegradability.