润滑科技信息平台

Refrigeration oil and compositions with carbon dioxide refrigerant

专利摘要

Lubricant compositions comprising certain mixtures of esters of pentaerythritol, di-pentaerythritol, tri-pentaerythritol and higher pentaerythritol oligomers are ideally suited for use with CO2 as refrigerant in heat transfer devices provided that at least 30% by weight of the esters are esters of pentaerythritol oligomers containing 4 or more pentaerythritol monomer units and wherein a majority of the alkylcarboxylate groups are straight chain C3-6 alkanoyl groups, such as n-pentanoyl. Said mixture of alkylcarboxylate esters are shown to not only have higher than expected viscosity and exceptional CO2 miscibility, but also possess excellent lubricity, film building properties and load bearing properties even as part of a lubricant/CO2 solution. ......

基本信息

专利类型:
发明专利
申请/专利号:
US13/080739
申请日期:
2011-04-06
专利申请人:
科聚亚公司
分类号:
["C09K5/04","C10M171/00","C10M177/00"]
发明/设计人:
CARR, DALE ， HUTTER, JEFFREY ， KELLEY, RICHARD ， URREGO, ROBERT ， HESSELL, EDWARD T.
权利要求: 1. A working fluid for a heat transfer device comprisingi) CO2 as a refrigerant, andii) a polyol ester lubricant composition having a viscosity index of 130 or higher comprising a mixture of esters of formula Iwherein n is an integer of from 1 to 20,each R is independently an alkyl carbonyl of from 5 to 10 carbon atoms,each R1 is independently selected and is either a group R or a substituent of formula II:and wherein from 70% to 100% of all R groups in the mixture of compounds of formula I are selected from isomers of alkyl carbonyl groups of 5 carbon atoms, at least 50% of all groups R in the compounds of formula I present in the working fluid are n-pentanoyl, and wherein the polyol ester lubricant composition ii) comprises:a) from 20 to 45 wt % compounds of formula I wherein n is 1 and each R1 is independently selected and is a group R,b) from 15 to 20 wt % compounds of formula I wherein n is 2 and each R1 is independently selected and is a group R,c) from 10 to 15 wt % compounds of formula I wherein n is 3 and each R1 is independently selected and is a group R, andd) from 30 to 55 wt % compounds of formula I which are pentaerythritol oligomers of 4 or more pentaerythritol monomer groups.2. The working fluid according to claim 1 wherein at least 70% of all R groups in the mixture of compounds of formula I are n-pentanoyl.3. The working fluid according to claim 1 further comprising in addition to components i) and ii), a hydrocarbon refrigerant, halocarbon refrigerant, ammonia, mineral oil, poly-α-olefin, alkylbenzenes, carboxylic acid ester other than a compound of formula I, polyether, polyvinyl ether, perfluoropolyether, phosphoric acid ester or mixture thereof.4. The working fluid according to claim 1 comprising a halocarbon refrigerant selected from the group consisting of carbon tetrafluoride (R-14), difluoromethane (R-32), 1,1,1,2-tetrafluoroethane (R-134A), 1,1,2,2-tetrafluoroethane (R-134), pentafluoroethane (R-125), 1,1,1-trifluoroethane (R-143A) and tetrafluoropropene (R-1234YF).5. The working fluid according to claim 1 further comprising one or more antioxidant, extreme-pressure additive, antiwear additive, friction reducing additive, defoaming agent, profoaming agent, metal deactivator, acid scavenger or mixture thereof.