High viscosity lubricating oils without V I improvers - made by treating oil fractions, opt contg 6-20C monolefins, with org peroxides

摘要

A mineral oil fraction, opt. contg. = one 6-20C monoolefins, is reacted at elevated temp. with an org. peroxide of formula R-O-O-R' (in which R and R' are alkyl, aryl or acyl). The original oil has initial b.pt. of 360 degrees C min., with wax content of 10 wt.%, and is a thiourea extract from a mineral oil fraction or a fraction from hydrocracking a mineral oil with wax content of =40 wt.%. The monoolefin pref. has 8-18C atoms and the peroxide is a 8-20C di-tert. alkyl peroxide, esp. di-tert. butyl peroxide, in amt. of 2.5-50 (2.5-40)wt.% based on the total hydrocarbon. Reaction is for 5 mins. to 10 h. at 100-225 degrees C such that at least 90 (95)% of the peroxide is decomposed. Multi-range engine oils are obtd. without the need to add polymeric V.I. improvers which are susceptible to shear and oxidn.