Abstract: A block copolymer is disclosed, which comprises a first block comprising polymerized units of an alkylene oxide and a second block comprising polymerized units of an alkylene oxide and a lactone, said copolymer being obtainable by polymerizing an alkylene oxide in the presence of an organic initiator to form said first block, and reacting the first block with a mixture of an alkylene oxide and a lactone. Such copolymers are found to have improved foam inhibition characteristics while maintaining their biodegradable properties.

Abstract: A composition is disclosed which comprises a lubricating oil and a refrigerant, wherein the lubricating oil comprises a polyalkyleneglycol derivative of the formula (I): RX(RaO)x(RbO)y(RcO)zRd, wherein: X?O or S, R is a C3 to C15 substituent comprising a heterocyclic ring, in which the heteroatom(s) in said ring is (are) oxygen and/or sulphur, Ra is a C2 alkylene group, Rb is a C3 alkylene group, Rc is a C4 alkylene group, Rd is the same as R, or is H, a C1-C20 alkyl or a C1-C20 acyl, x, y, z are each independently 0 or an integer of 100 or less, and x+y+z=4 to 100, but excluding compositions where the refrigerant is halogen-free and R contains a carbonate group. The use of borate esters as dehydrogenating agents in conjunction with the above lubricating oils is also disclosed.

Abstract: A block copolymer is disclosed, which comprises a first block comprising polymerised units of an alkylene oxide and a second block comprising polymerised units of an alkylene oxide and a lactone, said copolymer being obtainable by polymerising an alkylene oxide in the presence of an organic initiator to form said first block and reacting the first block with a mixture of an alkylene oxide and a lactone. Such copolymers are found to have improved foam inhibition characteristics whilst maintaining their biodegradable properties.

Abstract: A composition is disclosed which comprises a lubricating oil and a refrigerant, wherein the lubricating oil comprises a polyalkyleneglycol derivative of the formula (I): RX(RaO)x(RbO)y(RcO)zRd, wherein: X=O or S, R is a C3 to C15 substituent comprising a heterocyclic ring, in which the heteroatom(s) in said ring is (are) oxygen and/or sulphur, Ra is a C2 alkylene group, Rb is a C3 alkylene group, Rc is a C4 alkylene group, Rd is the same as R, or is H, a C1-C20 alkyl or a C1-C20 acyl, x, y, z are each independently 0 or an integer of 100 or less, and x+y+z=4 to 100, but excluding compositions where the refrigerant is halogen-free and R contains a carbonate group. The use of borate esters as dehydrogenating agents in conjunction with the above lubricating oils is also disclosed.

Abstract: A polyether having the formulaRX[(C.sub.x H.sub.2x O).sub.n (C.sub.y H.sub.2y O).sub.p Z].sub.m(I)wherein:R is either an alkyl or alkyl phenyl group having from 7 to 30 carbon atoms,X is selected from O, S or N;x is an integer from 2 to 4;y is an integer from 6 to 30;Z is a hydrocarbyl group containing from 1 to 30 carbon atoms;m is 1 when X is O or S or m is 2 when X is N;n and p are such that the polyether contains between 1 and 40% by weight of (C.sub.y H.sub.2y O) units and between 40 and 80% by weight of (C.sub.x H.sub.2x O) units; and the molecular weight of the polyether is between 500 and 3,500. Lubricating oil compositions comprising such polyethers are disclosed. A method of preparing the polyethers is disclosed and comprises preparing a H-capped polyether, preparing an alkali-metal salt thereof and reacting said salt with an alkylating agent.