配方类型: |
LUBRICANTS AND OILS |
配方说明: |
Raw Materials for Hydraulic-Brake Fluids |
配制方法: |
LUBRICANTS There has been a very positive and rapid trend in the direction of the use of polyglycols to replace the old standby, castor oil, as the lubricant in hydraulic-brake fluid formulations. The major driving forces for this development have been the superior viscosity-temperature characteristics and the lack of sludge formation on oxidation of the polyglycols. Sludge formation is eliminated because the oxidation products are either volatile or soluble. The Dow Chemical Company is producing polyglycol 15-200 (a water-soluble polyalkylene glycol derivative with a viscosity of 200 centistokes at 100'F.), and polyglycol P400, polyglycol P750, polyglycol P1200 and polyglycol P2000 (polypropylene glycols of the indicated molecular weights). Both polyglycol 15-200 and the polypropylene glycols have been used extensively in the manufacture of hydraulic fluids. Polyglycol 15-200, a relatively new compound, is completely water soluble and the water tolerance requirements of the S.A.E. specificatio |
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