| 摘要 |
A method of preparing an oil-soluble copolymer having a molecular weight of at least 1000 comprises copolymerizing a reaction mixture comprising:-(1) from 1 to 25% by weight based on the weight of the three specified components of an unsaturated heterocyclic nitrogen compound having the formula <FORM:0980393/C3/1> where Z is an oxygen atom or a CR2 group, R is a hydrogen atom or an alkyl group and R1 is an organic group containing a polymerizable ethylenic linkage (except that when R1 is a vinyl group, Z may not be -CR2 and at least one radical R must be an allyl group). (ii) One or more oil-solubilizing monomers being polymerizable unsaturated compounds each containing an allyl group of at least 8 carbon atoms the proportions of components (i) and (ii) being at least 50% by weight based on the weight of the three specified components and (ii) from 0% to 50% by weight of a third component, being one or more other polymerizable unsaturated compounds which contain neither allyl groups of at least 8 carbon atoms nor heterocyclic nitrogen-containing groups. Particularly suitable as monomers are the compounds of the general formula I wherein R1 represents a radical of the formula <FORM:0980393/C3/2> where R11/CO is an acyl radical derived from an unsaturated carboxylic acid, Z is an oxygen atom or a CR2 group and each of X and Y represents a hydrogen atom or a methyl group. The preferred oil solubilizing monomers are esters of unsaturated acids or esters of saturated acids derived from unsaturated alcohols. The monomers may be copolymerized by bulk, solution or emulsion polymerization using conventional free radical catalysts. Other additives such as pour point depressents, viscosity index improvers, blooming agents, corrosion inhibiters, oiliness agents and solubilizers may be added. |
