Abstract: A lubricating composition comprises at least 50 percent by mass, based on the mass of the composition of an oil of lubricating viscosity and 0.01 to 25 percent by mass, based on the mass of the composition of an oil-soluble poly(2-oxazine) polymer. The polymer has the repeat unit: where the number (n) of repeat units is an integer between 4 and 500, such as between 4 and 400. The polymer carries an inorganic or organic nucleophilic polymerisation terminating group (t), and an initiator group (i) connected to the N atom of a repeat unit, the initiator group (i) being effective to initiate the polymerisation of linear, branched or cyclic hydrocarbyl moieties. R1 comprises a single or a mixture of linear, branched or cyclic hydrocarbyl groups having 1-50 carbon atoms, some or all having 12-50 carbon atoms, or of at least one macro-monomeric hydrocarbyl group with more than 50 carbon atoms.

Abstract: A lubricating composition comprises a major amount of an oil of lubricating viscosity and 0.01 to 25 percent by mass, based on the mass of the composition of an oil-soluble copolymer. The copolymer comprises units (a) and units (b): —N(COR1)CH2CH2—??(a) —N(COR2)CH2CH2CH2—??(b) wherein the polymer carries an inorganic or organic nucleophilic polymerisation terminating group (t), and an initiator group (i) connected to the N atom of a repeat unit (a) or (b), the initiator group (i) being effective to initiate the polymerisation of linear, branched or cyclic hydrocarbyl moieties. R1 and R2 are the same or different and comprise a single or a mixture of linear, branched or cyclic hydrocarbyl groups having 1-50 carbon atoms, some or all having 12-50 carbon atoms, or of at least one macro-monomeric hydrocarbyl group with more than 50 carbon atoms.

Abstract: A lubricating composition comprises a major amount of an oil of lubricating viscosity and 0.01 to 25 percent by weight, based on the weight of the composition, of a poly(2-oxazoline) polymer. The polymer has the repeat unit: —N(COR1)CH2CH2— wherein the number of repeat units (n) in the polymer is an integer between 4 and 1000, such as between 4 and 500. The polymer carries an inorganic or organic nucleophilic polymerisation terminating group (t), and an initiator group (i) connected to the N atom of a repeat unit, the initiator group (i) being effective to initiate the polymerisation of linear, branched or cyclic hydrocarbyl moieties. At least 5% of the total number of the groups R1 in the polymer comprise alkenyl groups having between 15 and 20 carbon atoms.

Abstract: A lubricating composition comprises at least 50 percent by mass, based on the mass of the composition of an oil of lubricating viscosity and 0.01 to 25 percent by mass, based on the mass of the composition of an oil-soluble poly(2-oxazine) polymer. The polymer has the repeat unit: where the number (n) of repeat units is an integer between 4 and 500, such as between 4 and 400. The polymer carries an inorganic or organic nucleophilic polymerisation terminating group (t), and an initiator group (i) connected to the N atom of a repeat unit, the initiator group (i) being effective to initiate the polymerisation of linear, branched or cyclic hydrocarbyl moieties. R1 comprises a single or a mixture of linear, branched or cyclic hydrocarbyl groups having 1-50 carbon atoms, some or all having 12-50 carbon atoms, or of at least one macro-monomeric hydrocarbyl group with more than 50 carbon atoms.

Abstract: A lubricating composition comprises a major amount of an oil of lubricating viscosity and 0.01 to 25 percent by mass, based on the mass of the composition of an oil-soluble copolymer, The copolymer comprises units (a) and units (b): —N(COR1)CH2CH2—??(a) —N(COR2)CH2CH2CH2—??(b) wherein the polymer carries an inorganic or organic nucleophilic polymerisation terminating group (t), and an initiator group (i) connected to the N atom of a repeat unit (a) or (b), the initiator group (i) being effective to initiate the polymerisation of linear branched or cyclic hydrocarbyl moieties. R1 and R2 are the same or different and comprise a single or a mixture of linear, branched or cyclic hydrocarbyl groups having 1-50 carbon atoms, some or all having 12-50 carbon atoms, or of at least one macro-monomeric hydrocarbyl group with more than 50 carbon atoms.

Abstract: A lubricating composition comprises a major amount of an oil of lubricating viscosity and 0.01 to 25 percent by weight based on the weight of the composition, of a poly(2-oxazoline) polymer. The polymer has the repeat unit: —N(COR1)CH2CH2— wherein the number of repeat units (n) in the polymer is an integer between 4 and 1000, such as between 4 and 500. The polymer carries an inorganic or organic nucleophilic polymerisation terminating group (t), and an initiator group (i) connected to the N atom of a repeat unit, the initiator group (i) being effective to initiate the polymerisation of linear, branched or cyclic hydrocarbyl moieties. At least 5% of the total number of the groups R1 in the polymer comprise alkenyl groups having between 15 and 20 carbon atoms.