A lubricating oil including a lubricating oil base stock as a major component; and a mixture of (i) one or more protected lubricating oil additives having a first performance function, and (ii) one or more unprotected lubricating oil additives having a second performance function, as a minor component. The first performance function and the second performance function are the same. The one or more protected lubricating oil additives are inactive with respect to their performance function. The one or more protected lubricating oil additives are converted into one or more unprotected lubricating oil additives in the lubricating oil in-service in an engine or other mechanical component. A method for controlled release of one or more lubricating oil additives into a lubricating oil. A method for improving oxidative stability of a lubricating oil and extending performance life of one or more lubricating oil additives.

A lubricating oil including a lubricating oil base stock as a major component; and a mixture of (i) one or more protected lubricating oil additives having a first performance function, and (ii) one or more unprotected lubricating oil additives having a second performance function, as a minor component. The first performance function and the second performance function are the same. The one or more protected lubricating oil additives are inactive with respect to their performance function. The one or more protected lubricating oil additives are converted into one or more unprotected lubricating oil additives in the lubricating oil in-service in an engine or other mechanical component. A method for controlled release of one or more lubricating oil additives into a lubricating oil. A method for improving oxidative stability of a lubricating oil and extending performance life of one or more lubricating oil additives.

A lubricating oil including a lubricating oil base stock as a major component, and one or more lubricating oil additives having at least one protected active group, as a minor component. The one or more lubricating oil additives having at least one protected active group are converted into one or more lubricating oil additives having at least one unprotected active group in the lubricating oil in-service in an engine or other mechanical component. Compositions including one or more lubricating oil additives having at least one protected active group. A method for improving solubility of one or more lubricating oil additives in a lubricating oil. A method for improving oxidative stability of a lubricating oil and extending performance life of one or more lubricating oil additives. A method for improving friction control in an engine or other mechanical component lubricated with a lubricating oil.

A lubricating oil including a lubricating oil base stock as a major component, and one or more lubricating oil additives having at least one protected active group, as a minor component. The one or more lubricating oil additives having at least one protected active group are converted into one or more lubricating oil additives having at least one unprotected active group in the lubricating oil in-service in an engine or other mechanical component. Compositions including one or more lubricating oil additives having at least one protected active group. A method for improving solubility of one or more lubricating oil additives in a lubricating oil. A method for improving oxidative stability of a lubricating oil and extending performance life of one or more lubricating oil additives. A method for improving friction control in an engine or other mechanical component lubricated with a lubricating oil.

The invention relates to a lubricant comprising a polyalkylene glycol basestock, an aromatic amine of the formula (I) as defined hereinafter, and a thioether of the formula (II) as defined hereinafter. The invention further relates to a method for preparing the lubricant comprising the step of contacting the polyalkylene glycol basestock, the aromatic amine of the formula (I), and the thioether of the formula (II); and to a method for reducing the oxidative degradation of the lubricant comprising the step of contacting the polyalkylene glycol basestock, the aromatic amine of the formula (I), and the thioether of the formula (II).

##STR00001##

The invention relates to a lubricant comprising a polyalkylene glycol basestock, an aromatic amine of the formula (I) as defined hereinafter, and a thioether of the formula (II) as defined hereinafter. The invention further relates to a method for preparing the lubricant comprising the step of contacting the polyalkylene glycol basestock, the aromatic amine of the formula (I), and the thioether of the formula (II); and to a method for reducing the oxidative degradation of the lubricant comprising the step of contacting the polyalkylene glycol basestock, the aromatic amine of the formula (I), and the thioether of the formula (II).

##STR00001##

A compound represented by the formula:

##STR00001## wherein each R is independently selected from the group consisting of (i) substituted or unsubstituted alkyl with C=0 to 12 inclusive; wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 are each independently selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each independently selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; and wherein one of R.sup.1 and R.sup.2 and one of R.sup.3 and R.sup.4 may optionally be bridged by a polymethylene group to form a cycloalkyl; wherein when C=0 in R, the combined group R.sup.1 R.sup.2 is the same as the combined group R.sup.3 R.sup.4; and wherein when C=1 in R, each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are hydrogen.

A compound represented by the formula:

##STR00001## wherein each R is independently selected from the group consisting of (i) substituted or unsubstituted alkyl with C=0 to 12 inclusive; wherein X.sup.1, X.sup.2, X.sup.3 and X.sup.4 are each independently selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; wherein R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are each independently selected from the group consisting of alkyl, aryl, alkylaryl groups and hydrogen; and wherein one of R.sup.1 and R.sup.2 and one of R.sup.3 and R.sup.4 may optionally be bridged by a polymethylene group to form a cycloalkyl; wherein when C=0 in R, the combined group R.sup.1 R.sup.2 is the same as the combined group R.sup.3 R.sup.4; and wherein when C=1 in R, each of R.sup.1, R.sup.2, R.sup.3, and R.sup.4 are hydrogen.

A method of making antidegradant compounds is disclosed, in which a p-phenylenediamine is reacted with an alpha-hydroxy carbonyl compound to thereby obtain an enediamine, which is reduced to thereby obtain a mixture comprising the antidegradant compound.

Methods of making antidegradant compounds are disclosed in which a p-phenylenediamine is reacted with a dicarbonyl to thereby obtain a diimine, which is reduced to obtain mixtures comprising the antidegradant compound.