Abstract: A process for preparing a grafted polymer in which a substrate polymer is graft reacted with a nitrogen-containing grafting monomer in the presence of a free radical initiator and an amide coupling inhibitor that reduces polymer crosslinking during the graft reaction.

Abstract: The present invention includes star polymers which can be used as viscosity index improvers in oil compositions formulated for high performance engines. The star polymers have triblock copolymer arms of hydrogenated polyisoprene-polybutadiene-polyisoprene, which provide excellent low temperature performance in lubricating oils, and can be used in the presence of low pour point depressant concentrations.

Abstract: The present invention includes asymmetric triblock copolymers which are used as viscosity index improvers in oil compositions formulated for high performance engines. The triblock copolymers have the block structure hydrogenated polyisoprene-polystyrene-hydrogenated polyisoprene wherein the ratio of the number average molecular weights of the first and second hydrogenated polyisoprene blocks is at least 4.

Abstract: The present invention includes star polymers which can be used as viscosity index improvers in oil compositions formulated for high performance engines. The star polymers have triblock copolymer arms of hydrogenated polyisoprene and polystyrene wherein the polystyrene is placed near the core of the star polymer to provide excellent low temperature performance and finishability as a polymer crumb.

Abstract: An engine oil formulation comprising of a pour point depressant, a dispersant inhibitor package containing a reduced amount of ashless dispersant, a synthetic or mineral based oil or mixtures thereof, and a modified hydrogenated star polymer of a conjugated diolefin and a modified hydrogenated copolymer of conjugated diolefins and monoalkenyl arenes is disclosed. The engine oil has and exhibits improved dispersancy and rheological properties which is attributable to the presence therein of the modified hydrogenated star polymer of a conjugated diolefin and a modified hydrogenated copolymer of conjugated diolefins and monoalkenyl arenes. A process of producing the inventive engine oil composition is also disclosed.

Abstract: An improved VI improver and a fluid composition comprising the VI improver. The VI improver is an asymmetric radial polymer comprising a plurality of arms having at least two distinctly different peak molecular weights, which arms are chemically the same. The weight ratio of a longest set of arms and a first set of shorter arms will vary within the range from about 1.2:1 to about 8.0:1. If more than one set of shorter arms is used the ratio of adjacent arms molecular weights will vary within the same range. While the arm might be essentially any polymer, polymers of conjugated diolefins and copolymers of at least one monoalkenyl aromatic hydrocarbon and at least one conjugated diolefin are preferred. Conjugated diolefin homopolymers are preferred and polyisoprene is most preferred.

Abstract: A solid, cyclone-finishable polymer which does not exhibit cold flow and provides an unexpected balance of viscosity improving properties for oil compositions is produced by hydrogenating a copolymer comprising a homopolymer block of isoprene connected to a copolymer block of isoprene and a monoalkenyl aromatic hydrocarbon. The amount of the monoalkenyl aromatic hydrocarbon is sufficient to allow cyclone finishing although sufficiently distributed to provide oil compositions having good low temperature viscosity. Prior to hydrogenation, the copolymers have a number average molecular weight between 125,000 and 275,000, preferably 150,000 to 240,000, and a total monoalkenyl aromatic content between 10 and 2 percent by weight, preferably between 7 and 3 percent. The copolymer is hydrogenated to substantially saturate the isoprene and to reduce the size of monoalkenyl aromatic segments in the copolymer block.

Abstract: A solid, cyclone-finishable polymer which does not exhibit cold flow and provides an unexpected balance of viscosity improving properties for oil compositions is produced by hydrogenating a copolymer comprising a homopolymer block of isoprene connected to a copolymer block of isoprene and a monoalkenyl aromatic hydrocarbon. The amount of the monoalkenyl aromatic hydrocarbon is sufficient to allow cyclone finishing although sufficiently distributed to provide oil compositions having good low temperature viscosity. Prior to hydrogenation, the copolymers have a number average molecular weight between 125,000 and 275,000, preferably 150,000 to 240,000, and a total monoalkenyl aromatic content between 10 and 2 percent by weight, preferably between 7 and 3 percent. The copolymer is hydrogenated to substantially saturate the isoprene and to reduce the size of monoalkenyl aromatic segments in the copolymer block.

Abstract: A gear oil composition is provided, the composition comprising a hydrogenated star conjugated diolefin polymer having arms with weight average molecular weights between about 3,000 and about 15,000. Such star polymers are effective as viscosity index improvers, and yet are sufficiently shear stable for service in gear oil lubricants.

Abstract: Lubricating oil compositions which contain hydrogenated diene star polymers grafted with N-vinylimidazole exhibit improved engine performance when prepared by grafting the polymer in an oil mixture containing at least 6% by weight of the star polymer. The grafting is accomplished by contacting the polymer with from about 3.0 to about 5.5 wt % N-vinylimidazole when N-vinylimidazole is the sole reactant and from about 1.0 to about 5.0 wt % N-vinylimidazole when N-vinylimidazole is used in combination with N-vinylpyrrolidone.

Abstract: A star-shaped polymer useful as a polymeric VI improver comprising at least one arm which is a block copolymer containing a cunjugated diolefin block and a monoalkenyl aromatic hydrocarbon block and a plurality of arms which are either a homopolymer of a conjugated diolefin or a copolymer of two or more conjugated diolefin or a copolymer of two or more conjugated diolefins. Oil compositions comprising star-shaped VI improvers of this type exhibit relativelylow HTHSR viscosities, and hence, improved fuel efficients when used in automotive applications. Oil compositions comprising star-shaped VI improvers of this type also exhibit improved low temperature pumpability.

Abstract: A polymeric blend particularly useful as a VI improver, which polymeric blend comprises a selectively hydrogenated asymmetric radial polymer comprising a plurality of polymeric arms containing hydrogenated conjugated diolefin monomer units and at least one block copolymer arm comprising a single polymeric block containing predominantly monoalkenyl aromatic hydrocarbon monomer units and a single polymeric block containing predominantly hydrogenated conjugated diolefin monomer units and a selectively hydrogenated linear diblock copolymer containing a single polymeric block containing principally monoalkenyl aromatic hydrocarbon monomer units and a single polymeric block containing predominantly hydrogenated conjugated diolefin monomer units. Both polymers in the blend will be selectively hydrogenated so as to convert (saturate) at least 95% of the ethylenic unsaturation initially contained therein.

Abstract: A star-shaped polymer useful as a polymeric VI improver comprising at least one arm which is a block copolymer containing a conjugated diolefin block and a monoalkenyl aromatic hydrocarbon block and a plurality of arms which are either a homopolymer of a conjugated diolefin or a copolymer of tow or more conjugated diolefin or a copolymer of two or more conjugated diolefins. Oil compositions comprising star-shaped VI improvers of this type exhibit relatively low HTHSR viscosities, and hence, improved fuel efficiencies when used in automotive applications. Oil compositions comprising star-shaped VI improvers of this type also exhibit improved low temperature pumpability.

Abstract: An input/output processing module utilized for processing of signaling information and arranged in a central control unit of a local central office of a digital telecommunications system. Each central office further includes a central switching network and a plurality of trunks dedicated to common channel signaling each locally associated with a signaling link controller unit. Within the processing module, a microprocessor system is provided for initiating, starting and controlled resetting of transfers of signaling information under supervision of the central control unit. The signaling link controllers utilized for common channel signaling are residing on a separate signaling link bus. A signaling link bus control arrangement is connected to both the microprocessor system and the signaling link bus and includes programmable control means for sequentially executing transfer operations of signaling information.

Abstract: A lubricating oil composition for internal combustion engines having superior rust and corrosion inhibition is disclosed. The composition comprises a major amount of a hydrocarbon oil of lubricating viscosity and a minor amount of conventional additives, including an overbased detergent (such as calcium carbonate or calcium hydroxide) for rust protection and an ashless dispersant (such as the reaction product of substituted succinic acid or anhydrides with amines). The composition also includes a supplemental rust inhibitor (SRI) additive which is a combination of an effective amount of a supplemental rust inhibitor (SRI) additive comprising a combination of (A) R.sub.1 O[C.sub.2 H.sub.4 O].sub.x H and/or R.sub.2 O[C.sub.3 H.sub.6 O].sub.y H with (B) R.sub.3 O[C.sub.2 H.sub.4 O].sub.x [C.sub.3 H.sub.6 O].sub.y H and/or R.sub.4 O[C.sub.3 H.sub.6 O].sub.y [C.sub.2 H.sub.4 O].sub.x H, wherein R.sub.1, R.sub.2, R.sub.3 and R.sub.

Abstract: A lubricating composition having much improved high temperature performance characteristics comprises a major amount of a lubricating oil and a viscosity-index improving amount of a selectively sulfonated and selectively hydrogenated monoalkenyl arene-conjugated diene two block copolymer.