METHOD OF PRODUCING POLYALKYL METHACRYLATE ADDITIVES AND APPARATUS FOR REALISING SAID METHOD Russian patent published in 2012 - IPC C08F120/10 C08F120/18 C08F8/14 C10M145/14 C07C67/03 C07C69/54 

FIELD: chemistry.

SUBSTANCE: group of inventions relates to chemical engineering, particularly to methods of producing polyalkyl methacrylate additives for oil and oil products, paint compositions and adhesives with permanent tackiness. The method of producing polyalkyl methacrylate additives involves continuous production of alkyl methacrylates by re-esterification of methyl methacrylate with higher fatty alcohols in the presence of a catalyst and an inhibitor, followed by polymerisation of the obtained alkyl methacrylates in base oil. To obtain alkyl methacrylates, methyl methacrylate is inhibited and then mixed with a molten fraction of higher fatty alcohols in molar ratio 2-2.5:1 at temperature 65-70°. The obtained mixture is re-esterified in the presence of a heterogeneous catalyst to obtain alkyl methacrylates with simultaneous fractionation of the formed methanol in form of an azeotrope with methyl methacrylate. The obtained alkyl methacrylates are purified from residual methyl methacrylate and methanol by film evaporation. Methanol vapour and methyl methacrylate formed during re-esterification and film evaporation are cooled. The condensate obtained from cooling is mixed with ethylene glycol in order to dissolve methanol in it, with subsequent phase separation of the mixture into methyl methacrylate and ethylene glycol with dissolved methanol, after which methanol is separated from ethylene glycol and used as a ready product. Ethylene glycol is returned to the step for mixing with the condensate and methyl methacrylate is returned to the inhibiting step. To polymerise the purified alkyl methacrylates, a mixture of alkyl methacrylates and base oil is first prepared while stirring continuously at temperature 115-120°C. A suspension of a foaming agent in base oil is separately prepared and then continuously added to the hot reaction mixture for a period of time which enables polymerisation of alkyl methacrylates at temperature 115-120°C. After adding the foaming agent to the base oil, stirring of the reaction mixture continues until complete conversion of alkyl methacrylates to polymer to obtain a polymerisation product which is diluted with base oil to obtain polyalkyl methacrylate additives of given concentration. An apparatus for producing polyalkyl methacrylate additives is also disclosed.

EFFECT: obtained additives have high solubility in petroleum and synthetic oil, low volatility, non-toxicity, do not form ash when burnt and provide a high viscosity index and a low setting point of oil; also provided is a wasteless continuous technique for producing additives by continuous synthesis of alkyl methacrylates with extraction of an additional product - methanol, and polymerisation of alkyl methacrylates in base oil.

10 cl, 1 tbl, 1 dwg, 4 ex