Polyglycols as base fluids for environmentally-friendly lubricants

Polyglycols are used in a wide range of applications, including lubrication. Many advantageous properties can be obtained for lubricant applications by manipulating the four variables in polyglycol preparation: the initiator, the alkylene oxides, the molecular build-up, and the mole weight. However, it has long been believed that it would not be possible to combine these properties with a good environmental profile of high biodegradability and low aqueous toxicity. Development work at the authors' laboratory has resulted in polyglycol-chemistry-based products that fulfil the application requirements and are also environmentally friendly. Assessment by the Umwelt Bundes Amt has led to a statement of suitability for Blue Angel formulations for two water-soluble polyglycol grades (ISO 22 and IS0 46). Environmentally-friendly watersoluble polyglycol base stocks currently includes the range ISO 10 to ISO 100. The development of environmentally friendly water-insoluble and oil-soluble polyglycols is under way.