Lubricant compsn. - with improved antioxidant properties, used as turbine, hydraulic and gear oils

摘要

Compsn. (I) contains: (i) cpd. (A), as antioxidant where R1 and R2 = H or alkyl; R3 = H or methyl; R4 = H, alkyl or alkoxy; and R5 = H, phenyl, alkylphenyl or naphthyl. R1 and R2, R2 and R4, and R3 and R4 each can be a cycloaliphatic ring; and cpd. (II): where R = n- and iso-C4H9; and n- and iso-C5H11. Ratio (I):(II) is 5-1:1-5. USE/ADVANTAGE - Lubricant compsn. has improved antioxidant properties and used as turbine, hydraulic and gear oils. In an example, compsn. contg. cpds. (Ia) and (IIb) was tested for its antioxidancy and the concn. of the oxidn. prod. formed determined by IR spectroscopy (E/d value, where E is the max. extinction of the carbonyl band at 170 cm and d is the layer thickness of the sample) after testing at 120-160 deg. C in an air stream of 5l/hr. in the presence of a catalyst. The E/d value was 1.91 after 72 hrs. (0.53 after 8 hrs.). Prod. of methylene-bis-(N,N-dialkyldithiocarbomates) comprises reacting highly concentrated solns. of Na-N,N-dialkyldithiocarbomates (A) with methylene chloride (B). 0.55-0.6 mol. (B) are used per mol (A). (A) is produced from Na salt of N,N-dialkyldithiocarbamide acid and contains an excess of 0.05-0.2 mol. NaOH per mol. carbamate. During the course of the reaction, the temp. increses from room temp. to 80 to 90 deg. c.. USE/ADVANTAGE - The methylene carbomates can be used as additives for elastomers, lubricants or asphalt compsns.. Highly pure prod. is obtd.. In an example, a starting mixt. of (A) and (B) was stirred at room temp., the reaction temp. was raised over 1 hr. to 50-60 deg. C. then the 80 deg. C over 2 hrs., and subsequently heated to 90 deg. C for a short time to complete the reaction. 1-2 wt.% of a filtering auxiliary agent was added to the highly concentrated sol. of (A) before reacton, the soln. was filtered, and then reacted with methylene chloride. 1-2 wt.% Ca(OH)2 was added to the methylene-bis-(N,N-dialkyldithiocarmate) and then filtered.