Diesters, or dibasic acid esters, were developed during World War II and are the reaction product of long-chain alcohols and carboxylic acids. Historically, they have been effective as reciprocating compressor lubricants due to their low coking tendency at temperatures of 400°F or higher. They also provide excellent solvency and detergency. The aggressiveness of diesters toward elastomers, seals and hoses has limited the usefulness of these fluids. Newer fluids, such as polyol esters, meet the needs of many applications formerly filled by diesters. 雙酯或二元酸酯於第二次世界大戰所開發，是種長鏈醇和羧酸的反應產物。在歷史上，由於它們低焦化的溫度傾向400°F以上，因此，它們跟往復式壓縮機潤滑油一樣有效。它們還提供極佳的溶解力和去污力。像這種具攻擊性的雙酯，彈性體、密封件和橡皮管都限制使用這類實用的液體。新型液體，如多元醇酯，就滿足了以往對雙酯的需求。 Polyol esters, or Neopentyl poly esters, have largely replaced diesters in high-temperature applications where oxidative stability is critical. Common applications include their use as lubricants in aircraft engines, high-temperature gas turbines, hydraulic fluids, and as heat exchange fluids. They can also be used as a co-blended basestock with PAOs to enhance additive solubility and reduce the tendency of PAOs to shrink and harden elastomers. 多元醇酯或新戊聚酯已經廣泛地取代雙酯在高溫下的運用，在這種情況下，氧化穩定性是非常重要的。常見的應用包括作為飛機引擎的潤滑油、高溫燃氣渦輪機、液壓油，以及作為熱交換介質。它們也能跟烯烴被用作為混合基礎油，以提高溶解性，並減少烯烴收縮及硬化彈性體的趨勢。------------------------------------------------------------------------------------------- 有機酯類(Organic Esters)（高雄礦油公會提供） 酯類的特性是抗氧化性特強、溶解性佳，因此酯類合成油生成酸性物質的量少，齒輪及軸承磨耗量也最少，同時再高溫下也不容易成膠漆或結碳，至產品劣化時不易形成積垢，但酯類僅與少數物質相容，造成軸封的膨脹率大。酯類又分為單酯類、雙酯類及多元酯類，單酯類可用於透平油、雙酯類則可用於噴射引擎、空壓機、低溫齒輪油、航空機用低溫油脂儀表潤滑及其他用途。目前使用最廣乏（Polyol Ester）多元醇酯，它的高溫穩定及清潔性都很好，潤滑性比（Diester）雙酯要高，蒸發性低，在兩種金屬表上，易吸收極性分子，形成保護膜。