CN105121610A - Modified hydrogen-based lubricants - Google Patents

Modified hydrogen-based lubricants Download PDF

Info

Publication number
CN105121610A
CN105121610A CN201480021243.1A CN201480021243A CN105121610A CN 105121610 A CN105121610 A CN 105121610A CN 201480021243 A CN201480021243 A CN 201480021243A CN 105121610 A CN105121610 A CN 105121610A
Authority
CN
China
Prior art keywords
compound
lubricant
group
halogen
chain
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
CN201480021243.1A
Other languages
Chinese (zh)
Inventor
M.阿瓦塔内奧
E.德尼索夫
D.维西诺
C.A.P.托内里
G.马奇安尼
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Solvay Specialty Polymers Italy SpA
Original Assignee
Solvay Solexis SpA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Solvay Solexis SpA filed Critical Solvay Solexis SpA
Publication of CN105121610A publication Critical patent/CN105121610A/en
Pending legal-status Critical Current

Links

Classifications

    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10MLUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
    • C10M169/00Lubricating compositions characterised by containing as components a mixture of at least two types of ingredient selected from base-materials, thickeners or additives, covered by the preceding groups, each of these compounds being essential
    • C10M169/04Mixtures of base-materials and additives
    • C10M169/042Mixtures of base-materials and additives the additives being compounds of unknown or incompletely defined constitution only
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10MLUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
    • C10M107/00Lubricating compositions characterised by the base-material being a macromolecular compound
    • C10M107/38Lubricating compositions characterised by the base-material being a macromolecular compound containing halogen
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10MLUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
    • C10M109/00Lubricating compositions characterised by the base-material being a compound of unknown or incompletely defined constitution
    • C10M109/02Reaction products
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10MLUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
    • C10M2211/00Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
    • C10M2211/02Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only
    • C10M2211/0206Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only used as base material
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10MLUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
    • C10M2211/00Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
    • C10M2211/02Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only
    • C10M2211/024Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only aromatic
    • C10M2211/0245Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen and halogen only aromatic used as base material
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10MLUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
    • C10M2211/00Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
    • C10M2211/04Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen, halogen, and oxygen
    • C10M2211/0406Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen, halogen, and oxygen used as base material
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10MLUBRICATING COMPOSITIONS; USE OF CHEMICAL SUBSTANCES EITHER ALONE OR AS LUBRICATING INGREDIENTS IN A LUBRICATING COMPOSITION
    • C10M2211/00Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions
    • C10M2211/04Organic non-macromolecular compounds containing halogen as ingredients in lubricant compositions containing carbon, hydrogen, halogen, and oxygen
    • C10M2211/044Acids; Salts or esters thereof
    • C10M2211/0445Acids; Salts or esters thereof used as base material
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2020/00Specified physical or chemical properties or characteristics, i.e. function, of component of lubricating compositions
    • C10N2020/01Physico-chemical properties
    • C10N2020/02Viscosity; Viscosity index
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2030/00Specified physical or chemical properties which is improved by the additive characterising the lubricating composition, e.g. multifunctional additives
    • C10N2030/06Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2030/00Specified physical or chemical properties which is improved by the additive characterising the lubricating composition, e.g. multifunctional additives
    • C10N2030/08Resistance to extreme temperature
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2030/00Specified physical or chemical properties which is improved by the additive characterising the lubricating composition, e.g. multifunctional additives
    • C10N2030/10Inhibition of oxidation, e.g. anti-oxidants
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2040/00Specified use or application for which the lubricating composition is intended
    • C10N2040/04Oil-bath; Gear-boxes; Automatic transmissions; Traction drives
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2040/00Specified use or application for which the lubricating composition is intended
    • C10N2040/06Instruments or other precision apparatus, e.g. damping fluids
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2040/00Specified use or application for which the lubricating composition is intended
    • C10N2040/135Steam engines or turbines
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2040/00Specified use or application for which the lubricating composition is intended
    • C10N2040/25Internal-combustion engines
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2040/00Specified use or application for which the lubricating composition is intended
    • C10N2040/25Internal-combustion engines
    • C10N2040/252Diesel engines
    • CCHEMISTRY; METALLURGY
    • C10PETROLEUM, GAS OR COKE INDUSTRIES; TECHNICAL GASES CONTAINING CARBON MONOXIDE; FUELS; LUBRICANTS; PEAT
    • C10NINDEXING SCHEME ASSOCIATED WITH SUBCLASS C10M RELATING TO LUBRICATING COMPOSITIONS
    • C10N2040/00Specified use or application for which the lubricating composition is intended
    • C10N2040/30Refrigerators lubricants or compressors lubricants

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Organic Chemistry (AREA)
  • Lubricants (AREA)

Abstract

The invention provides modified hydrogen-based lubricants. The present invention relates to a process for the manufacture of hydrogen-based lubricants modified with per (halo) fluorinated aromatic compounds, to the modified lubricants thereby obtained and to the use of the modified lubricants for the preparation of lubricant compositions.

Description

The hydrogen base lubricating agent of modification
This application claims the right of priority of the European Patent Application No. 13163768.8 submitted on April 15th, 2013, for all objects, this full content applied for is combined in this by reference.
Technical field
The present invention relates to the hydrogen base lubricating agent of the lubricant of modification, particularly modification.
Background technology
It is known that natural or synthesis source some hydrogen base lubricating agent, particularly some lubricating oil, there is remarkable lubricant characteristics and be commercially obtainable with rational cost.The example of hydrogen based lubricating oil comprises the mineral oil of hydrocarbon type, animal and plant winterized stearin, the winterized stearin comprising the synthesis of polyalphaolefin (PAO), diester, polyol ester, phosphoric acid ester, polyester, alkylating naphthalene, polyphenylene oxide, polybutene, polyalkylated pentamethylene, silane hydrocarbon, siloxanes and polyalkylene glycol.
This type of oil can be formed uniformly on substrate to be lubricated, the film of cohesively; Cohesiveness be in any lubricant applications, especially in automotive vehicles applications make us wish key characteristic.But, they there is low thermostability and thermo-oxidative stability and low unreactiveness and therefore they be not suitable for wherein reach a high temperature and the reactive species that this lubricant film wherein may be caused to degrade formed lubricant applications.
On the contrary, (entirely) perfluoroalkyl polyether (PFPE) lubricant, namely the lubricant of perfluor alkylene oxide groups chain (namely comprising the chain of the repeating unit with at least one ehter bond and at least one fluothane part) is comprised, have high heat tolerance and chemical resistance, therefore they are useful when being characterized as the application of mal-condition (very high temperature, there is oxygen, use aggressive chemical product and radiation etc.) and the degraded risk of this lubricant film is high.However, with regard to adhesion characteristics and film toughness PFPE lubricant be performance than hydrocarbon ils difference, they be expensive and viewed from thermostability viewpoint condition severe (that is, wherein this lubricant temperature is no more than 150 DEG C) wherein application in or win.
Therefore, the lubricant that the intermediate characteristic had between hydrogen base lubricating agent and PFPE lubricant is desirably provided will be made us.Particularly, by making us desirably providing, there is the heat higher than PFPE lubricant and chemical stability, the high tolerance for wearing and tearing and friction and be simultaneously comparatively cheap hydrogen base lubricating agent.
From KOBRINA, L.S., polyfluoro is for some uniquenesses (Somepeculiaritiesofradicalreactionsofpolyfluoroaromaticc ompounds) of the free radical reaction of aromatics, fluorine chemistry magazine (JournalofFluorineCemistry), 1989, the 142nd volume, the 3rd phase, 301-344 page is it is known that the aromatics in polyfluoro generation stands the addition reaction with (fluorine) organic free radical; This document specifically disclosed the peroxidation penta fluoro benzene formyl of thermolysis in phenyl-hexafluoride to provide dimer and addition complex.The document there was reported, the reaction of octafluoro toluene, octafluoro naphthalene and decafluorobiphenyl under the existence of benzoyl peroxide as radical source, and the reaction of the alkyl diradical that phenyl-hexafluoride is different from polarity and space requirement (namely producing the methyl from tert-butyl peroxide and cyclohexyl free radical).These reactions are at KOBRINA, L.S., and the free radical reaction (Radicalreactionsofpolyfluoroarenes) of polyfluoro aromatic hydrocarbons, fluorine takes down notes (Fluorinenotes) 2012, the 2nd volume, the 81st interim further discussion.
Also at BROOKE, G.M., polyfluoro is for the preparation (Thepreparationofpolyfluoroaromaticandheteroaromaticcompo unds) of aromatic series and heteroaromatic compound, fluorine chemistry magazine (JournalofFluorineChemistry), 1997,86th volume, the 1st phase, discloses some organic group at polyfluoro for the addition reaction on aromatics in 1-76 page.But these two sections of last prior art documents have only been paid close attention to and have been added on some fluoro aromatics by lower molecular weight (entirely) fluoroalkyl or (entirely) fluoroalkanoyl superoxide; In addition, only have studied this addition reaction for mechanism (mechanicistic) object.
EP2100909A (Su Weisu Simon Rex company (SOLVAYSOLEXISS.P.A.)) 9/16/2009 discloses following methods, the method is with the addition compound of providing package containing at least one fluoridized non-aromatic cyclic group on aromatics PFPE superoxide being added to (halogen) entirely and fluoridize, and this non-aromatic cyclic group has at least two substituting groups (comprising PFPE chain) and optionally conjugation or unconjugated double bond.These addition compound be suitable as fluid that additive fluoridizes for (entirely) and the lubricant that (entirely) fluoridizes or based on material for the manufacture of colloid and/or graft polymerization compositions.
The reaction of fluoridized aromatics and hydrogen base lubricating agent all do not taught by above prior art document.
WO2012/007374 (Su Weisu Simon Rex company) 1/19/2012 discloses segmented copolymer, this segmented copolymer comprises one or more PFPE section, one or more polyalkylene section and optionally at least one complete (halogen) non-aromatic cyclic part of fluoridizing, and this non-aromatic cyclic part has carbon atom and optionally conjugation or the unconjugated double bond of at least two sp3 hydridization of the PFPE section be chemically bonded on it.This document does not disclose the addition compound that the ring compound by hydrocarbon ils free radical addition being fluoridized to complete (halogen) obtains.
US3720646 (Montedisons SPA (MONTEDISONS.P.A.)) 3/13/1973 discloses the reaction product of PFPE and the optionally naphtoquinone compounds of halogenation; This document same does not disclose the addition compound that the ring compound by hydrocarbon ils (as polyalphaolefin or mineral oil) free radical addition being fluoridized to (halogen) entirely obtains.
Have been found that now that the hydrogen base lubricating agent of improvement can by they obtain with the modification of perfluor aromatics.
Summary of the invention
Therefore, the present invention relates to a kind of method for being added to by hydrogen base lubricating agent on the aromatics that (halogen) entirely fluoridize, described method comprises hydrogen base lubricating agent [lubricant (R h)] compound [compound (A)] of cyclic group [group (F ')] fluoridized containing at least one complete (halogen) with providing package of the free radical reaction of aromatics [compound (F)] of fluoridizing with complete (halogen), and this group (F ') there is at least one the lubricant chain [chain (R be bonded thereto hC)], described group (F ') optionally containing conjugation or unconjugated double bond.
Separately will be called at this " lubricant of modification " according to the obtainable compound of the present invention [A].
For purposes of the present invention, statement " hydrogen base lubricating agent " is intended to refer to one or more lubricants (or natural or synthesis or semisynthetic), and its range of viscosities is from 2cSt to 1,000,000cSt, preferably from 2cSt to 3,000cSt, and containing straight or branched hydrocarbon part.Therefore, hydrogen base lubricating agent under being included in room temperature (25 DEG C) be in liquid form those (i.e. lubricating oil) and be at room temperature those (as lubricating wax or lubricating grease) of being in semi-solid form.The hydrogen base lubricating agent being applicable to object of the present invention is the lubricating oil comprising the following: the mineral oil of hydrocarbon type, animal or plant oil, synthetic oil (as polyalphaolefin (PAO)), diester, polyol ester, phosphoric acid ester, polyester, alkylating naphthalene, polyphenylene oxide, polybutene, polyalkylated pentamethylene, silane hydrocarbon, siloxanes and polyalkylene glycol.Preferably, this hydrogen base lubricating agent is mineral oil or the polyalphaolefin of hydrocarbon type.
For the sake of clarity, " one or more lubricants (R is stated h) " be intended to refer to " one or more hydrogen base lubricating agents (R h) ".
Be not wishing to be bound by theory, the method is typically via from lubricant (R h) extract hydrogen out and form free radical lubricant chain (R hC) carry out, this free radical lubricant chain (R hC) add on compound (F) to form free radical species (R hC– F '), these free radical species and another free radical (R hC) reaction, generate type R hC-F '-R hCdisubstituted addition compound (A), wherein by lubricant chain (R cH) be linked to the sp of group (F ') 3on the carbon of hydridization.Free radical (R hC-F) can also one to react with internus R hC-F '-F '-R hCaddition compound; Some free radicals (R hC-F) can also combine with hydrogen atom, internus R thus hCthe mono-substituted addition compound (A) of-F '-H, this addition compound (A) can experience again aromizing to form compound (A), wherein (F ') be aromatic cyclic groups and its medium chain (R cH) be linked to the sp of group (F ') 2on the carbon of hydridization.
Do not limit the selection of the aromatics [compound (F)] that this complete (halogen) is fluoridized particularly, as long as this compound is aromatic and be that complete (halogen) is fluoridized, i.e. its not hydrogen atoms and comprise at least one fluorine atom.
For avoiding doubt, term " aromatics " is intended to refer to the ring texture with delocalization conjugated pi system at this, this delocalization conjugated pi system has the multiple π delocalized electrons meeting Huckel's rule (H ü ckel ' srule) (number of π-electron equals (4n+2), and wherein n is integer).
The aromatics (F) that (halogen) is fluoridized entirely can be monocycle or many rings and can comprise one or more than one aromatic ring.If it comprises more than one aromatic ring, these aromatic rings can be condensation or non-condensation.Compound (F) can be heteroaromatic compound, comprises one or more heteroatoms (such as O, S, N) and can be substituted or not be substituted in ring.
Preferably, compound (F) is fluoridized, and namely its all free valencys are all saturated by fluorine atom.
The limiting examples being applicable to the compound (F) of object of the present invention is notably perfluor benzene, perfluorinated biphenyl, perfluor naphthalene, perfluor anthracene, perfluor pyridine, perfluorotoluene and its comprise the derivative of one or more perfluorinated substituent.The preferred embodiment of compound (F) is perfluor benzene (phenyl-hexafluoride) and perfluorinated biphenyl (decafluorobiphenyl).
Can by making lubricant (R according to free radical reaction of the present invention h) to contact with organic or inorganic superoxide, redox system, ozone or hydrogen peroxide with compound (F) and cause; It can also by heat or photochemical breakdown lubricant (R h) cause.
Organo-peroxide comprises such as diacyl peroxide, peroxyester (peroxyester), peroxy dicarbonate (peroxidicarbonate), dialkyl peroxide, ketone peroxide, ketal peroxide (peroxyketal), hydroperoxide, they are solvable in above-mentioned hydrogen base oil; More preferably, this organo-peroxide is selected from benzoyl peroxide and ditertiary butyl peroxide (DTBP).
Inorganic peroxide comprises such as ammonium peroxydisulfate, Potassium Persulfate, Sodium persulfate and Potassium peroxysulfate.
The example of redox system comprises based on those of Fe (II) ion be combined with following item: hydrogen peroxide, organo-peroxide (comprising alkyl peroxide, hydroxyl peroxide, acyl peroxide), peroxydisulfate, peroxide diphosphate; Can also many middle employing Cr (II) in these systems, V (II), Ti (III), Co (II) and Cu (I) ion substitution Fe (II) ion.Can also adopt based on Organic Alcohol and the redox system of transition metal being selected from Ce (IV), V (V), Cr (VI) and Mn (III).
Lubricant (R h) thermolysis can by generation free radical (R hC) such temperature under heat lubricant (R h) and the mixture of compound (F) realize; This temperature depends on concrete lubricant (R to be modified h), and one by one can be determined according to known method by those of ordinary skill in the art.Under any circumstance, this temperature normally higher than 150 DEG C, typically higher than 200 DEG C.
Lubricant (R h) photochemical breakdown can by making lubricant (R h) and the mixture of compound (F) stand source of radiation (comprising UV ray, X-ray and gamma-radiation source) and come.Typically carried out in the presence of photoinitiators by the photochemical breakdown being exposed to UV ray; this light trigger comprises such as, benzoin ether, phenmethyl ketal, α-dialkoxy-methyl phenyl ketone, Alpha-hydroxy-alkyl-benzophenone, alpha-amino group-alkyl-benzophenone, acylphosphine oxide, benzophenone, benzo amine (benzoamine), sulfo--xanthone, sulfo--amine, two luxuriant titaniums.But, if hydrocarbon ils contains the functional group that can produce free radical when being exposed to UV ray, can avoid using light trigger; The example of this type of functional group is carbonyl.
Preferably do not having to carry out method of the present invention under solvent; But, also can use solvent, if especially lubricant (R h) be highly viscous, if particularly viscosity is higher than 3,000cSt, to make lubricant (R h) and compound (F) close contact.Solvent by by those of ordinary skill in the art one by one according to concrete lubricant (R h) and compound (F) selection, its selection mode may disturb at lubricant (R for it does not produce h) and compound (F) between the free radical of reaction.The example of suitable solvent is organic solvent (as alkane, ketone, ester and aromatic solvent), optionally chlorination or fluoridize.
At lubricant (R h) and compound (F) between weight ratio typically scope from 0.01 to 1.000, more preferably between 0.05 and 100 and even more preferably between 0.1 and 10.
This reaction usually under magnetic force or mechanical stirring and under an inert atmosphere (such as in a nitrogen atmosphere) carry out.
If this free radical reaction is by making lubricant (R h) to contact with organic or inorganic superoxide with compound (F) and cause, then typically with scope from 20 DEG C to 250 DEG C, preferably from the mode set temperature of 50 DEG C to 200 DEG C.Temperature of reaction is determined by those of ordinary skill in the art on the decomposition kinetics basis of superoxide.Optionally, in order to keep lubricant free radical (R in whole process hC) concentration in defined scope, this temperature can be improved linearly over time or progressively.
If this free radical reaction is by making lubricant (R h) to contact with redox system with compound (F) and cause, then this free radical reaction is typically carried out from-40 DEG C to 250 DEG C, preferably in scope from the temperature of 20 DEG C to 100 DEG C.
If this free radical reaction is by lubricant (R h) use light trigger photochemical breakdown or by lubricant (R h) radiation-induced decomposition to cause, then this free radical reaction is typically carried out from-100 DEG C to 200 DEG C, preferably in scope from the temperature of-40 DEG C to 120 DEG C.
If this free radical reaction is by lubricant (R h) thermolysis cause, then this free radical reaction is typically carried out from 100 DEG C to 350 DEG C, preferably in scope from the temperature of 150 DEG C to 300 DEG C.
This reaction can or carry out in batches or in the groove type reactor of semi-batch or continuously stirring.
At the end of this reaction, the resistates of excessive compound (F), any organic initiators and any undesirable byproduct are removed by using technology as known in the art (such as by distillation or solvent extraction).Can also carry out subsequently filtering to remove any solid impurity.Typically under reduced pressure distill at the temperature of temperature starting thermolysis lower than this lubricant.As an alternative, water-vapor phase distillation can be used.Typically use dissolve excessive compound (F) but the halogenated solvent of dissolved compound (A) do not extract; Among halogenated solvent, (entirely) perfluoroalkyl polyether (PFPE) solvent is preferred.
Typically, method of the present invention allows to obtain compound (A), wherein relative to the weight of compound (A), the weight percentage ranges of cyclic group [group (F ')], preferably fluoridized cyclic group that complete (halogen) is fluoridized is from 1% to 15%, preferably from 2% to 12%.
Another object of the present invention is compound [compound (A)], this compound (A) comprises cyclic group that at least one complete (halogen) fluoridize [group (F ')], and this group (F ') there is at least one lubricant (R be bonded thereto h) chain [chain R hC], described group (F ') optionally containing conjugation or unconjugated double bond.Compound (A) is obtainable by method of the present invention.
For clarity sake, at statement " lubricant (R h) chain [chain R hC] " in, " lubricant (R h) " refer to " hydrogen base lubricating agent (R as defined above h) ".
In compound (A), this at least one lubricant chain can be incorporated into the sp of group (F ') 2on the carbon of hydridization (when aromizing occurs in this process again) or be attached to the sp of group (F ') 3on the carbon of hydridization.Typically, compound (A) comprises at least two lubricant chains, and each link is incorporated at least one sp of group (F ') 3on the carbon atom of hydridization.
Typically, in compound (A), relative to the weight of this compound (A), the weight percentage ranges of cyclic group [group (F ')], preferably fluoridized cyclic group that complete (halogen) is fluoridized is from 1% to 15%, preferably from 2% to 12%.
According to preferred embodiment of the present invention, compound (A) meets following formula (I):
Wherein:
-R hCand R ' hC, be same to each other or different to each other, representative is attached to sp separately 3lubricant chain (R on the carbon atom of hydridization hC);
-X fand X f ', be same to each other or different to each other, be selected from halogen and C 1-C 12(halogen) fluothane substituting group, is preferably selected from-F and C entirely 1-C 12perfluoroalkyl or perfiuoroaryl;
The non-aromatic cyclic part [partly (NA)] that-NA representative complete (halogen) is fluoridized, this circular part (NA) optionally with the cyclic condensation of other aromatic series or non-aromatic, optionally there is one or more conjugation or unconjugated double bond, optionally there is one or more complete (halogen) fluoro substituents, and wherein said circular part comprises with R hCand R ' hCtwo sp of chain 3the carbon of hydridization.
The unrestricted example of the structure contained by the above-mentioned general formula of compound (A) is as described in detail above notably the following:
Wherein R hC, R ' hCas lubricant chain defined above and W ffluorine atom or C 1-C 6perfluoroparaffin group.
According to preferred embodiment of the present invention, in compound (A), (R cH) represent the lubricant chain of mineral oil or polyalphaolefin.According to another preferred embodiment, compound (A) comprises at least one lubricant chain of being selected from mineral oil and polyalphaolefin and at least one the fluoridized cyclohexyl optionally containing conjugation or unconjugated double bond or dicyclohexyl (F ').
According to compound of the present invention (A) as lubricant, be especially used as the lubricant of following item: I. C. engine oil (comprising motor car engine, tractor engine, gas engine, marine diesel), gear, ballistic systems, compressor (such as spiral-lobe compressor, roots compressor (rootscompressor), turbo-driven compressor, for generating compressed-air actuated compressor), refrigerator, turbine, power station and windmill.Therefore, the invention still further relates to the lubricating method comprising and use compound (A).
Although preferably former state uses compound (A), they can also mix to form lubricant compositions with other composition and additive.Therefore, the present invention comprises the method (comprise and use compound (A)) manufacturing lubricant compositions further, and lubricant compositions (one or more compounds (A) containing mixing with other composition and additive).The example of other composition is unmodified hydrocarbon ils; But, also can use (entirely) perfluoroalkyl polyether oil (PFPE oil).The example of suitable PFPE oil is in European patent application EP 2100909 cited above, be appointed as those of compound (1)-(8).Metal detergent, ashless dispersant, antioxidant, rust inhibitor (being separately called rust-preventive agent), emulsifying agent, extreme-pressure additive, friction modifier, viscosity index improver, pour point depressant and suds suppressor also can as having to be added to the other composition/additive in modified lubricant of the present invention to prepare lubricant compositions.Select by technician according to the certain expected purposes in view of common practise according to compound (A) to be prepared for the manufacture of the other composition be applicable to of lubricant compositions and additive and method, such as basis is by MANG, the lubricant that the people such as Theo edit and lubrication (Lubricantsandlubrication), 2nd edition, Wei Yin Haimu: Willie limited-liability company of-VCH press (Weinheim:Wiley-VCHVerlagGmbH) 2007.
Lubricant compositions containing compound (A) can be the form such as in emulsion oil-in-water, oily oil-in emulsion, lubricating grease, paste, suspension or powder; The form of said composition will be selected according to specific desired use by technician.
The present invention is favourable in some.The toxicological risks of the inventive method is relatively low, because unlike the aromatics of nonfluorinated, fluoridized aromatics is normally harmless.In addition, they are solvable usually in hydrocarbon ils, therefore can avoid using solvent; This allows not only to reduce toxicological risks, also reduces production cost.Due to the superior oxidative stability of compound (A), reduce compared with those of C&M cost and corresponding unmodified lubricant.
Be illustrated in more detail in the present invention's experimental section below.
Be combined in this patent, patent application and the disclosure content of publication and the afoul degree of the description of the application by reference if any to term may be caused unclear, then this explanation should be preferential.
Experimental section
materials and methods
From FOX lubricant company (FuchsLubricants) buy mineral oil ( iV), from the vigorous lubricant company of Crewe ( lubrication) polyalphaolefin 400/40 (PAO400/40), polyalphaolefin 65/40 (PAO65/40) is buied.
From Sigma-Aldrich company buy decafluorobiphenyl (perfluorinated biphenyl) and phenyl-hexafluoride (perfluor benzene).
Benzoyl peroxide (water 70%wt) and ditertiary butyl peroxide (DTBP) is buied from Sigma-Aldrich company.
All reagent all uses with the former state received.
At Varian record on 300MHz spectrograph 19f-NMR spectrum; Sample: the 10%wt solution in normal hexane.
Use Perkin pYRIS1TGA instrument carries out Dynamic Thermal gravimetric analysis.
At Nicolet fT-IR spectrograph records FT-IR spectrum.With sRVIII trier carries out rub(bing)test.In the following example, statement " phenyl-hexafluoride part " and " decafluorobiphenyl part " is intended to comprise and derives from selected lubricant and add to any cyclic group on phenyl-hexafluoride and decafluorobiphenyl respectively, and this cyclic group optionally contains conjugation or unconjugated double bond.
example
The reaction of example 1-polyalphaolefin 400/40 (PAO400/40) and decafluorobiphenyl
The decafluorobiphenyl (216mmol) of PAO400/40,72g of 40g and the benzoyl peroxide (52mmol) of 18g are placed in a nitrogen atmosphere in the glass flask of 250ml, this glass flask is equipped with magnetic stirring apparatus.
This mixture is heated to 80 DEG C until it becomes uniform solution, then from the heating gradient of 80 DEG C to 120 DEG C, it was stirred 4.5 hours with 300rpm according to every 30 minutes amplitudes of 5 DEG C.
Finally, by this reaction mixture in vacuum (10 -2millibar), be up to and distill to remove excessive decafluorobiphenyl (bp=208 DEG C) and by product (mainly phenylformic acid) at 230 DEG C with the PAO of modification obtaining 45.3. 19f-NMR analyzes display, there is the decafluorobiphenyl part of by weight 8.5%.
The reaction of example 1bis – polyalphaolefin 400/40 (PAO400/40) and decafluorobiphenyl
Follow as same program in example 1, difference uses the decafluorobiphenyl (48mmol) of 16g and the benzoyl peroxide (15mmol) of 5g.Obtain the PAO of the modification of 41.2g, and 19f-NMR analyzes and confirms the decafluorobiphenyl part that there is 2%wt.
The reaction of example 2-polyalphaolefin 65/40 (PAO65/40) and decafluorobiphenyl
Follow as same program in example 1, difference is the PAO400/40 using the PAO65/40 of 40g to replace 40g.
Reclaim the PAO of the modification of 47.98g, and 19f-NMR analyzes and confirms the decafluorobiphenyl part that there is 10.2%wt.
The reaction of example 3-polyalphaolefin 400/40 (PAO400/40) and decafluorobiphenyl
To being equipped with the polyalphaolefin (PAO400/40), the decafluorobiphenyl of 9.2g and the ditertiary butyl peroxide (DTBP) of 0.98g that add 5g in the stainless steel autoclave of the 45ml of magnetic stirring apparatus.This autoclave to be immersed in liquid nitrogen and to apply three vacuum-nitrogen circulation.Finally, this autoclave be heated to room temperature and pressurize under the nitrogen of 2 bar.
This reaction is carried out 4.5 hours at 130 DEG C.Finally, this reaction mixture is cooled to room temperature, and excessive decafluorobiphenyl and by product are passed through at 230 DEG C 10 -2the PAO of the modification to provide 5.72g is removed in the lower distillation of millibar. 19f-NMR analyze alleged occurrence by weight 7.5% decafluorobiphenyl part.
The reaction of example 4-mineral oil and decafluorobiphenyl
By the mineral oil of 10g the decafluorobiphenyl (53mmol) of IV, 18g and the benzoyl peroxide (13mmol) of 4.6g are placed in the glass flask of 100ml in a nitrogen atmosphere, and this glass flask is equipped with magnetic stirrer.
This mixture is heated to 80 DEG C until it becomes uniform solution, then from the heating gradient of 80 DEG C to 120 DEG C, it was stirred 4.5 hours with 300rpm according to every 30 minutes amplitudes of 5 DEG C.
Finally, by this reaction mixture in vacuum (10 -2millibar), be up to and distill to remove excessive decafluorobiphenyl (bp=208 DEG C) and by product (mainly phenylformic acid) at 230 DEG C to obtain the oil of the modification of 9.0g. 19f-NMR analyzes the decafluorobiphenyl part that display exists by weight 9.5%.
The reaction of example 5-mineral oil and phenyl-hexafluoride
By the mineral oil of 10g the phenyl-hexafluoride (54mmol) of IV, 10g and the benzoyl peroxide (13mmol) of 4.6g are placed in the glass flask of 100ml, and this glass flask is equipped with magnetic stirring apparatus and condenser.
This mixture is heated to 80 DEG C under reflux in a nitrogen atmosphere and then at 80 DEG C, stirs 8 hours with 300rpm.
Reaction mixture is distilled under the same conditions as in example 1 the oil of the modification that 8.98g is provided. 19f-NMR alleged occurrence by weight 3.1% phenyl-hexafluoride part.
The reaction of example 6-polyalphaolefin 65/40 (PAO65/40) and phenyl-hexafluoride
To provide magnetic stirring apparatus 45ml stainless steel autoclave in add the polyalphaolefin PAO65/40 (PAO65/40) of 5g, the phenyl-hexafluoride of 5g and the benzoyl peroxide of 2.3g.This autoclave to be immersed in liquid nitrogen and to apply three vacuum-nitrogen circulation.Finally, this autoclave be heated to room temperature and carry out this reaction with every 30 minutes heating gradients of 5 DEG C from 80 DEG C to 120 DEG C with the nitrogen pressurization of 2 bar.
Finally, this reaction mixture is cooled to room temperature, and excessive phenyl-hexafluoride and by product are passed through at 150 DEG C 10 -2the PAO of the modification to provide 4.91g is removed in the lower distillation of millibar. 19f-NMR confirm existence by weight 5.7% phenyl-hexafluoride part.
The reaction of example 7-polyalphaolefin 65/40 and phenyl-hexafluoride
Follow as the same program in example 6, difference is the DTBP using 1.02g, and after with this autoclave of the nitrogen pressurization of 2 bar, this reaction is carried out lasting 6 hours at 130 DEG C.After the excessive phenyl-hexafluoride of distillation and by product, reclaim the PAO of the modification of 5.29g. 19f-NMR analyze confirm existence by weight 8.9% phenyl-hexafluoride part.
thermooxidizing is tested
The assessment of test 1-thermostability
The dynamic TGA carrying out the PAO of the modification of PAO400/40 and example 1 in atmosphere with the heating rate of 10 DEG C/min analyzes.Result provides in the following table:
Table 1
These results show in the PAO of the modification of example 1, to observe the weight loss identical with PAO400/40 at the temperature of high 40 DEG C-65 DEG C; Therefore, according to the PAO of modification of the present invention, there is higher thermostability.
The assessment of test 2-thermo-oxidative stability
Be heated to 200 DEG C under magnetic stirring, in the presence of the air and continue 12 hours in the glass flask PAO of the modification of the example 1 of PAO400/40 and 20g of 20g being placed on two 100ml.Analyzed the content of the carbonyl measured in often kind of PAO (the 50%wt solution in normal hexane) (peak of these carbonyls drops on 1719cm by FT-IR -1to 1721cm -1scope in).
Result provides in following table 2:
Table 2
These results show, compared with in PAO400/40, there is the increase of significantly lower carbonyl content in the PAO of modification of the present invention; Therefore, the PAO of modification of the present invention has higher thermo-oxidative stability.
Test 3-rub(bing)test
Exist according to ASTMD6425 – 05 (2010) trier carries out rub(bing)test.Compared with corresponding unmodified PAO, in the PAO of the modification of example 1 and 2 and in the blend of PAO and the PAO400/40 of the modification of example 1, observe the reduction of COF (frictional coefficient) and wearing and tearing.
Table 3
The assessment of the thermostability of the product of test 4-example 7
The dynamic TGA carrying out the PAO of the modification of PAO65/40 and example 7 in atmosphere with the heating rate of 10 DEG C/min analyzes.Result provides in the following table:
Table 4
These results show in the PAO of the modification of example 1, to observe the weight loss identical with PAO400/40 at the temperature of high 10 DEG C-35 DEG C; Therefore, according to the PAO of modification of the present invention, there is higher thermostability.
The assessment of the thermo-oxidative stability of the product of test 5-example 7
Be heated to 200 DEG C under magnetic stirring, in the presence of the air and continue 12 hours in the glass flask PAO of the modification of the example 7 of PAO65/40 and 20g of 20g being placed on two 100ml.Analyzed the content of the carbonyl measured in often kind of PAO (the 50%wt solution in normal hexane) (peak of these carbonyls drops on 1719cm by FT-IR -1to 1721cm -1scope in).
Result provides in the following table:
Table 5

Claims (14)

1., for hydrogen base lubricating agent being added to a method for the aromatics that (halogen) is entirely fluoridized, described method comprises hydrogen base lubricating agent [lubricant (R h)] compound [compound (A)] of cyclic group (F ') fluoridized containing at least one complete (halogen) with providing package of the free radical reaction of aromatics [compound (F)] of fluoridizing with complete (halogen), and this cyclic group (F ') there is at least one the lubricant chain (R be bonded thereto h) [chain (R hC)], described group (F ') optionally containing conjugation or unconjugated double bond.
2. method according to claim 1, wherein lubricant (R h) be one or more lubricants, its range of viscosities from 2cSt to 1,000,000cSt and containing straight or branched hydrocarbon part.
3. method according to claim 2, wherein lubricant (R h) be at room temperature be in liquid or semi-solid form.
4. method according to claim 3, wherein lubricant (R h) be the mineral oil, animal or plant oil, synthetic oil, diester, polyol ester, phosphoric acid ester, polyester, alkylating naphthalene, polyphenylene oxide, polybutene, polyalkylated pentamethylene, silane hydrocarbon, siloxanes and the polyalkylene glycol as polyalphaolefin (PAO) that are in liquid form and are selected from one or more hydrocarbon types.
5. method according to claim 4, wherein oil (R h) be mineral oil or the polyalphaolefin of hydrocarbon type.
6. method according to any one of claim 1 to 5, wherein this free radical reaction is by making lubricant (R h) to contact with organic or inorganic superoxide, redox system, ozone, hydrogen peroxide with compound (F) or by heat or photochemical breakdown lubricant (R h) cause.
7. method according to claim 6, wherein this organo-peroxide is benzoyl peroxide or ditertiary butyl peroxide.
8. the method according to any one of claim 1-7, the method is carried out in the absence of solvent.
9. the method according to any one of claim 1-8, wherein compound (F) be selected from perfluor benzene, perfluorinated biphenyl, perfluor naphthalene, perfluor anthracene, perfluor pyridine, perfluorotoluene and its comprise the derivative of one or more perfluorinated substituent.
10. method according to claim 9, wherein compound (F) is selected from perfluor benzene and perfluorinated biphenyl.
11. 1 kinds of addition compound [compound (A)], comprise cyclic group that at least one complete (halogen) fluoridize [group (F ')], and this group (F ') there is at least one the hydrogen base lubricating agent (R be bonded thereto h) chain [chain R hC], described group (F ') optionally containing conjugation or unconjugated double bond.
12. 1 kinds of methods for lubricating, the method comprises use compound as claimed in claim 11 (A).
13. 1 kinds of methods for the manufacture of lubricant compositions, the method comprises use compound as claimed in claim 12 (A).
14. 1 kinds of lubricant compositions, comprise the compound as claimed in claim 11 (A) mixed with other composition and additive.
CN201480021243.1A 2013-04-15 2014-04-10 Modified hydrogen-based lubricants Pending CN105121610A (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP13163768 2013-04-15
EP13163768.8 2013-04-15
PCT/EP2014/057233 WO2014170196A1 (en) 2013-04-15 2014-04-10 Modified hydrogen-based lubricants

Publications (1)

Publication Number Publication Date
CN105121610A true CN105121610A (en) 2015-12-02

Family

ID=48092820

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201480021243.1A Pending CN105121610A (en) 2013-04-15 2014-04-10 Modified hydrogen-based lubricants

Country Status (5)

Country Link
US (1) US20160046887A1 (en)
EP (1) EP2986692A1 (en)
JP (1) JP2016514762A (en)
CN (1) CN105121610A (en)
WO (1) WO2014170196A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA3101044A1 (en) * 2018-05-25 2019-11-28 Chevron Oronite Company Llc Method for preventing or reducing low speed pre-ignition in direct injected spark-ignited engines with silane-containing lubricant

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3720646A (en) * 1970-07-04 1973-03-13 Montedison Spa Perfluoropolyethers modified with quinone compounds in the polymeric chain and process for their preparation
CN102015828A (en) * 2008-03-14 2011-04-13 索维索莱克西斯公开有限公司 (Per)fluorinated addition products
WO2011136379A1 (en) * 2010-04-26 2011-11-03 株式会社Moresco Cyclophosphazene compound, lubricant comprising same, and magnetic disk

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101853987B1 (en) * 2010-07-14 2018-05-02 솔베이 스페셜티 폴리머스 이태리 에스.피.에이. Fluoroelastomer composition

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3720646A (en) * 1970-07-04 1973-03-13 Montedison Spa Perfluoropolyethers modified with quinone compounds in the polymeric chain and process for their preparation
CN102015828A (en) * 2008-03-14 2011-04-13 索维索莱克西斯公开有限公司 (Per)fluorinated addition products
WO2011136379A1 (en) * 2010-04-26 2011-11-03 株式会社Moresco Cyclophosphazene compound, lubricant comprising same, and magnetic disk

Also Published As

Publication number Publication date
WO2014170196A1 (en) 2014-10-23
JP2016514762A (en) 2016-05-23
US20160046887A1 (en) 2016-02-18
EP2986692A1 (en) 2016-02-24

Similar Documents

Publication Publication Date Title
US8258090B2 (en) Fluorinated lubricants
EP0597369B1 (en) New phosphazene derivatives and use of same as stabilizers for oils and greases based on perfluoropolyethers
JP4667761B2 (en) Refrigerator oil composition
JP6227550B2 (en) Process for producing (per) fluoropolyether having aromatic end groups
JP5925003B2 (en) Lubricating oil composition and equipment using the same
JP4354208B2 (en) Additives for perfluoropolyether oil
EP2882793A2 (en) (PER)FLUOROPOLYETHERS WITH bi- OR ter-PHENYL END GROUPS
US5681921A (en) Perfluoroalkyleneethertriazine oligomer and process for producing the same
JP2006348291A (en) Fluorinated grease with low torque level at low temperature
EP3233965A1 (en) Water-based composition comprising a fluorinated polymer
JP2017523292A (en) Lubricating method with alkoxylated perfluoropolyether
CN105121610A (en) Modified hydrogen-based lubricants
CN106574205A (en) Alkyl capped oil soluble polymer viscosity index improving additives for base oils in industrial lubricant applications
WO2011082029A1 (en) Lubricant base stocks based on block copolymers and processes for making
EP4363462A1 (en) Copolymers comprising (per)fluoropolyether chains
EP3337883B1 (en) Lubricant with sulfur-containing polyalkylene glycol
JP2006348292A (en) Fluorinated lubricant
JP6826694B2 (en) Grease composition
CN107474912A (en) A kind of high viscous finger, the Industrial gear oil composition of wide temperature range and its application
EP3337884B1 (en) Fluid with polyalkylene glycol and unsaturated ester
JP4636837B2 (en) Dioxolane derivative and method for producing the same
JP2016535768A (en) Modified hydrocarbon
JP2013112786A (en) Method for improving flash point of oil or oil composition, and oil composition improved in flash point
KR20240090772A (en) Lubricating grease containing a copolymer of tetrafluoroethylene oxide and hexafluoropropylene oxide
WO2016124579A1 (en) (per)fluoropolyether polymers as antifoam agents

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
WD01 Invention patent application deemed withdrawn after publication

Application publication date: 20151202

WD01 Invention patent application deemed withdrawn after publication