| 摘要 |
Cyclic ethers are polymerized or copolymerized in homogeneous liquid phase using very low concentrations of heteropolyacid catalyst to produce essentially linear polyoxyalkylene polymers. The product of the polymerization contains less than 2 weight percent cyclic oligomer by-product and has a molecular weight distribution (Mw/Mn) between 1 and 2. Alcohols, acyl-containing compounds and alkalies can be used as end-caps to terminate polymerization or modify the properties of the polymer produced. The process produces polyoxyalkylene copolymers and block copolymers that are useful as lubricants. The copolymers have a high viscosity index and are compatible with mineral oil and synthetic hydrocarbon lubricants. Preferred comonomers are tetrahydrofuran, C2-C20 monoepoxides and oxetan.
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