A hydrophilic copolymer that can form a surface lubricious layer exhibiting superior lubricating property and durability (lubrication retaining property), is provided. A hydrophilic copolymer having a good solvent solubility is provided. A hydrophilic copolymer is provided containing: structural units derived from a polymerizable monomer (A) having a sulfobetaine structure; structural units derived from a polymerizable monomer (B) having at least one group selected from the group consisting of a sulfonic acid group (SO.sub.3H), a sulfuric acid group (OSO.sub.3H), a sulfurous acid group (OSO.sub.2H), and groups of salts thereof; and structural units derived from a polymerizable monomer (C) having a photoreactive group.

The present invention relates to the field of lubricant, and specifically provides a lubricant composition and its preparation method and use. The lubricant composition comprises a base oil and rubber particles having radiation crosslinked structure dispersed therein, wherein the base oil is continuous phase and the rubber particles are dispersed phase. The viscosity of the lubricant composition of the present invention can be effectively adjusted as temperature changes. As compared with the lubricant composition comprising chemically crosslinked rubber particles, it has a lower viscosity at low temperatures and a higher viscosity at high temperatures, and has a relatively high viscosity index, which can meet the application requirements at the temperature above 200? C. In addition, the lubricant composition of the present invention also has excellent antiwear and friction-reducing properties.

The invention relates to a copolymer and a substrate having a surface, at least one part of which is coated with an epilame agent comprising at least one compound in the form of a copolymer comprising V units, N units, optionally at least one M unit, and optionally at least one P unit, linked by covalent bonds by their main chains, wherein

##STR00001## wherein W, X, Y, Z are spacer arms, T is a tracer group arranged to determine the concentration of epilame agent in an epilame-coating bath, L is a halogenated, preferably fluorinated, C.sub.1-C.sub.20 carbon moiety, A is a substrate anchoring moiety, Q is H, CH.sub.3, or a hydrocarbon chain different from T.

The invention also concerns a method for coating such a substrate with epilame, said method comprising a step of checking the concentration of epilame agent in the epilame-coating bath by means of the tracer group and if necessary, a step of readjusting the concentration of epilame agent in the epilame-coating bath.

A lubricious coating for a medical device is formed including first and second coated layers. The first coated layer is between the second coated layer and the device surface and includes a vinyl pyrrolidone polymer and a photo reactive group. The second coated layer is in direct contact with the first coated layer and is a top coating that includes an acrylic acid polymer. The second coated layer can optionally include photoreactive groups. The coating was found to have a very low number of particulates (e.g., 10 m or greater) which is very desirable for in vivo use.

A lubricious coating for a medical device is formed including first and second coated layers. The first coated layer is between the second coated layer and the device surface and includes a vinyl pyrrolidone polymer and a photo reactive group. The second coated layer is in direct contact with the first coated layer and is a top coating that includes an acrylic acid polymer. The second coated layer can optionally include photoreactive groups. The coating was found to have a very low number of particulates (e.g., 10 m or greater) which is very desirable for in vivo use.

The present invention relates to a method for preparing a polyisobutyl benzene sulfonate comprising the steps of alkylation of benzene with a terminal unsaturated polyisobutene to produce a polyisobutyl benzene, sulfonation of the polyisobutyl benzene to produce a polyisobutyl benzene sulfonic acid, and neutralizing the polyisobutyl benzene sulfonic acid to produce a polyisobutyl benzene sulfonate. The invention also relates to the polyisobutyl benzene sulfonate, the polyisobutyl benzene sulfonic acid, the polyisobutyl benzene, and to a lubricant comprising the polyisobutyl benzene sulfonate, to a fuel comprising the polyisobutyl benzene sulfonate, and to a use of the polyisobutyl benzene sulfonate as lubricant additive or fuel additive.

Embodiments of the disclosure include lubricious coatings. In an embodiment the disclosure includes a lubricious coating for a medical device including first and second coated layers. The first coated layer is between the second coated layer and the device surface and includes a vinyl pyrrolidone polymer and a photo reactive group. The second coated layer is in direct contact with the first coated layer and is a top coating that includes an acrylic acid polymer. The second coated layer can optionally include photoreactive groups. The coating was found to have a very low number of particulates (e.g., 10 m or greater) which is very desirable for in vivo use.

Embodiments of the disclosure include lubricious coatings. In an embodiment the disclosure includes a lubricious coating for a medical device including first and second coated layers. The first coated layer is between the second coated layer and the device surface and includes a vinyl pyrrolidone polymer and a photo reactive group. The second coated layer is in direct contact with the first coated layer and is a top coating that includes an acrylic acid polymer. The second coated layer can optionally include photoreactive groups. The coating was found to have a very low number of particulates (e.g., 10 m or greater) which is very desirable for in vivo use.