Document 65Rodw33Jg2opZevwkLvxeJoR
ARNG-054?
THE SCIENCE OF ORGANIC FLUOROCHEMISTRY
3M February 5, 1999
000002
`The Science of Organic Fluorochemistry
Introduction
"The scienceoffluorochemistry begins with family and is one of the most reactive of all
fluorine. Fluorine the elements. It is
is the most capable of
abundant member of the halogen combining with nearly every other
clement in the periodic table, which is why elemental fluorine is rarelyif ever found in nature. The strength of
the fluorine bond with other elements also made the discoveryofelemental fluorine a difficult task. Elemental
fluorine was not isolated until 1886, a relatively late date, as chemical discoveries go. Therefore, the science
offluorochemistry is relatively young. Becauseofits strong electronegative properties, ionic fluorine will
mfeotraml wfelauokribdoensdasrewitthehomthoesrtecleocmtmroonnegcahteimviecaaltofmosrmasndofvefrluyosrtinreonfgobuonnddisn wniatthureel,escutrcohpoassitfilvueorastpoamrs.(CalFo)ni.c
Naturally occurring fluorinated hydrocarbon molecules rarely occur in nature because of the energy required to
make or break the carbon-fluorine bond in biological systems. However, partially and fully fluorinated organic
molecules can be synthesized.
3M Experience in Fluorochemistry 3M Company began its history in fluorochemistry with the licensingof specific intellectual property from Dr. SEliemcotnrso-oCfhPemeincnalStFaltueoUrniinvaetrisoint(yEiCnF)1,945t.o syDnrt.heSsiimzoenosrghaandofdleuvoerlionpeemdolaepcruolceess.s,Innotwhisrepfreorcreesds,tooarsgaSniimcons feedstocks are dispersed in liquid, anhydrous hydrogen fluoride, and an electric current is passed through the solution, causing the hydrogen atoms on the molecule to be replaced with fluorine. The predominant `component of the products produced by this process have the same carbon skeletal arrangement as the feedstock used with all of the hydrogen atoms replaced by fluorine. However, fragmentation and rearrangement of the carbon skeleton can also occur and significant amountsof cleaved, branched and cyclic structures may be formed. The degree of fluorination of the organic feedstock is also dependent upon the tshpeecliefnigtchaofrbtoinmcehatihne lpernogctehssofisthruen.feeIdtsitsopcokssainbdlepatroasmyenttehressoizfetfhuellEyCfFluporrioncaetsesdsourcphearsfleuloercotroircgaalnciucrrent and molecules where all of the hydrogen atomsofthe hydrocarbon feedstock have been replaced by fluorine. aitmopmrso.ve3tMhebSuiilmtotnhse EfiCrsFt mparnoucfeascstfuorritnhgeppirlootduscctalieonEoCfFflpuroorcoecshseimnic1a9l4p9roadnudcthsa.s cCounrtrienntuleyd,t3o Mdevheaslotphraened manufacturing sites in the United States using the ECF process (Cottage Grove, MN, Cordova, IL, and Decatur, AL).
3M Production of Sulfonyl-based Fluorochemicals
3M has produced sulfonyl based fluorochemicals commercially for over 40 years using the ECF process. A
basic building block of such products and the highest production volume fluorochemical 3M manufactures is
perfluorooctanesulfonyl (Reaction 1)
fluoride
(POSF).
The
starting
feedstock
for
this
reaction
is
1-octanesulfonyl
fluoride.
Reaction 1
2CHpSOF + 34 HF 1-Octanesulfonyl fluoride
4570V
pu
2CFuSOF + 17H,
ECF
Perfluorooctanesulfonyl fluoride (POSF)
2
000003
etnizsymimaptoirctahyndtrtoolyusnidseorsftPaOnSdFt.hat Upnerdfelruoarpoproocptrainaetseuclofnodniitciaocnisd. (thPeFOpeSr)flwuiolrloroecstualntefsruolmfotnhaetechaenmiiocnalcaonrform
sbarlotks ewnitdhowmonnofuvratlheerntchmeemtiaclallilcyc.atTiohnesr.efCourrerPenFtOiSnfios rtmhaetuilotnimsattreondgelgyrsaudpaptoirotns
that PFOS or its salts cannot product from POSF derived
be
fluorochemicals and will persist in that form.
`The electrochemical fluorination process of biproducts and wasteof unknown and
yields about 35%-40% straight chain (normal) POS, variable composition comprised of the following
and
a
mixture
1)
higher and CoF15S02F
lower straight-chain homologs, ie., n-CnFan. SOSF, which comprise about 7%of the process output
.g.,
CF
nSO:F,
CF1sSOF,
2)
branched-chain, output
perfluoroalkylsulfony!
fluorides
with
various
chain
lengths,
about
18-20%of
the
3)
straight-chain, branched, and about 20-25%of the output
cyclic
(non-functional)
perfluoroalkanes
and
ethers,
which
comprise
4) "htyadrrso"g(ehni,gwhhmioclheccuolmaprriwesiegahbtouftlu1or0o-c1h5e%miocfalthbeypourtopduutc.ts) and other byproducts, including molecular
eBleeccatursoechoefmisclaiglhtflduiofrfienraetnicoenspirnopcreoscsevsasriceosndsiotmioenwsh,artawfrmoamtelroita-ltso,-laotndanedqufirpommenptl,antt-hteo-mpilxatntu.reTphreodpurocdeudcbtythtahte rheosmuoltlsogfureosm.elTehcetrcoocmhmemeirccailalfilzuoerdinPaOtiSoFn idserthiuvsednoptroadupcutrse acrheemaimciaxltuburte roafthaeprparomxiixmaotfeliyso7m0e%rslainnedar POSF derivatives and 30% branched POSF derived impurities.
pDeurrfilnugorpormodeutchtainoen,,hbayvperobdeuecntsveanntdedwatosttehepraotdmuocstpshearreefionrtmheed.pasTth,ebuvtoliamtpilreowvaesmteentpsroadruectusn,dseurcwhayasto capture
and destroy incinerator.
these releases by The byproducts,
thermal oxidation. many of which are
The tarsare incinerated incompletely fluorinated
at an with
in-house, hydrogen
hazardous atoms stil
waste present,
ctoancobnetrroelclyecd,leidn-bhaocuksei,ntwoatshteewEaCtFerptrroecaetsmsenotr asryestpeamrst.ialTlyhedetgrreaadtemdenitnssltuadbigleiziasteiiotnheprrolcaensdsfeisll,eadnodrdliasncdh-arged
incorporated. Someofthe non-POSF byproducts are recovered and sold for secondary uses.
sPuObSstEanisceistsuesleafd cionmmmaenrcyioatlhleyrv3iaMblfeluporordoucchte,mibcuatlisprpordiumcatrs.ilyTahneimmapjoorrtiatnytiisnutseerdmetdoiaptreodiunctehefusnycnttihoensailslyof
dfelruiovraotcihzeemdicfalluso,rotchehiermiaccarlosnyamnsd,hcihgehmmioclaelcnualamre,weaingdhtfoprmoullyamse.ricTporoadulcetsss.erTeaxbtelnet,1 siodemnetihfioemsosloomgeues of
POSF, [CFz-1)SO;F where n=other than intermediates in the formation of other 3M
8), principally perfluorohexanesulfonyl fluoride, are also products. PFOS is also a commercialized product for a variety
of
specific applications.
sUuslifnognyPlOfSluForaisdeamboaisiectyboufitldhiengmoblloeccku,leunuisqiunegcchoenmviesnttriioensaclahnybderoccraerabteodn breyacdteiroinvsa.tizCihnagrtPO1 SoFutltihnreosugthhethe
`general classesoffluorinated materials made by the "tree". POSF is reacted with methyl or ethyl
3M. The amine to
major intermediates are produce either N-methyl
represented or N-
by
the
trunk
of
eeitthhyelrpNe-rfmleutohryolocotranNe-seutlhfyolnpaemrifdleuo(rFoOoScAt)a.nesFulOfSonAamiisdsouebtsheaqnuoelnt(lFyOSreEa)c.ted with ethylene carbonate to form
3
000004
Chart 1
POSF Fluorochemical Reaction Tree Alcohols
FEasttteyrsAcid Phosphate Esters
Urethanes
Copolymers
Adpates
Acros
(-AyperuordodFao.nsufonanidoethano)
Silanes
Amides
Carboxyiates
Oxazoldinones,
Aloyiates
(N-Akyiperfudi@hesufonamide)
Amines
Quaternary Ammonium Saks
Amphotercs
(PerfuorcocPtOanSeFsulfony fuoride)
Sulfonates (PFOS)
4
000005
|||
FA D ierlfrer enOe S -- 5ra.m y..SOMO 1 -
J fSoEi TN. .....m--m a--a--, --
?a F Ee D 1 T e ee [er HC,
[ues
=
a aa a ate
rat
The secondary reactions necessarily produce pure
producing products.
all of these There may
derivatives be varying
aamroeusnitngsleoforflsueoqruoecnthieamlicbaaltcrhespirdouaclesss(eusnrtehaatctdeod
not or
pfianratliaplrloydruecatc.teTdypsitacratlilnyg,mtahteesreiarlessiodruailnstearrmeedpiraetseesn,t astucahcaosncFenOtSraAtioornFoOfS1E%) othratleassr.e cSaurcrihedprfoocrewsasreds atroethuender
oafccoonmtmienrucoiusaliimzparbloevepmreodnutctp.lanIttios riemdpuocretaonrtetloimuinndaetresttahnedprtheastentchee onofnu-nfnleucoersoscahreymirceaslidmuoailsetiinesthaedpdreoddutcottihoen
seunlvfiornoynlmefnltuaolr,idaengdrmoeutpaobofliPcO).SFAgcaainn,alstohebteerrmeimnoavlepdrotdhurcotugohfasuvcharideetygorafdadteigornadwaitlilobnepProFcOeSs.ses (chemical,
Physical-Chemical Properties
hFalluoogreinnsa,teid.e.orbgraonmiicnsea,reanldescshwleolrlinde,eswchriibcehdhianvtehebesecinenmtoifriec tlhitoerroautgurhelythiannveosrtgiagnaitcedmoblyemcualneys rbeesaerairncgheortsheirn
published reports. To propertiesoffluorine.
uFnldueorrsitnaenhdafslsueovreirnaaltecdhaorragcantiecr.istpircospewrhtiiecsh,
it is necessary differ from the
to describe in more other halogens and
detail the contribute
to the unusual propertiesoffluorochemicals.
hFalluoogreinnse,haansdaivsainsodsetrerWicaaalllyssriamdiiluasrotfo a1.h3y5dAr,oxmyolrgerocuopm.paFrlaubolreinteohtahsatothfe ohxigyhgeesnt ealnedctsrmoanlelgeartitvhiatny o(t4h.e0r--
cPaarubloinn-gflsucaolrei)noefbaolnld.thTehhealcoagrebnosn,-falnudortihneehbioghnedstisionntehoef
periodic table. the strongest
This confers a in nature (~110
strong polarity to the kcal/mol). See Table
2
and also
3. This lead to
very strong. high energy the persistenceofcertain
bond contributes fluorochemicals.
to the stabilityoffluorochemicals. That stability confers a variety of
Such unique
stability may properties to
fluorocarbons as described in Table 4.
TABLE 2 Fluorocarbon Structure
Considerations
Structure HCH HGF H;C-Cl HsC-Br HC
Bond Length
A 1 1.385 178 1.93 213
Atomic Van Der Waals'
Radius A 1.20 135 180 1.95 215
Bond Strength Keal/Mole
101 107 81 67 55
6
000007
TABLE 3 Effect of Increasing Fluorination
Structure
Bond Length
A
Bond Strength Keal/Mole
HiC-F HFC HEC-F FCF
1385
107.0
1358
109.6
1332
1146
1317
1160
TABLE 4 Stability of Fluorocarbons
Chemical Unaffected by any normal reagent React with alkali metals at high temperatures
Thermal and Oxidative
Stable in air at high Non-flammable
temperatures
Electrical * High electric strength Low dielectric constant
7
000008
`The high ionization potential of fluorine (401.8 keal/mole) and its low polarizability leads to weak inter- and
intramolecular interactions. This is demonstrated in the low boiling pointsoffluorochemicals relative to
molecular weight, and their extremely low surface tension and low refractive index. Table 5 `compares the
physical properties
polarizability.
ofa
perfluoroalkane
with
its
hydrocarbon
analog
to
demonstrate
the
effect
of
low
Low Boiling Point: MW Bp (C)
Low Heatof Vaporization
G-Cal/Gram Low Refractive Index
Np20 Low Surface Tension
Dynes/cm
TABLES
Physical Properties
(Effect of Low Polarizability)
CsFis
CsHis
438
114
97
125
20
86.8
1.280
1.3975
15.0
21.8
`The partitioning behaviorofperfluoroalkanes is also unique. Some perfluoroalkanes, when mixed with
`ohlyedorpohcoabribconasndanhdydwraotperh,obfiocr.m Athrcehearigmemdismcoiibeltey,phsauscehs,asdecmaornbsotxyrlaitcinagcitdh,atsuplefrofnliucoraicniadt,epdhcohsapihnastearoerbaoth
quaternary ammonium
soluble becauseofthe
hgyrdoruopp,hiwlhiec nnaattutraechoefdtthoestehechpaerrgfeludormioineattieeds.chaTihne,rmefaokrees,
the molecule more water
such functionalized
fluorochemicals can have surfactant properties.
A conventional hydrocarbon surfactant generally may be represented as:
Tnsoluble Tail
Co)
Hydrophilic Group
Where Ry... represents the hydrocarbon "tail" and *X represents a solubilizing group.
8
000009
Ina similar fashion, fluorochemical surfactants can typically be described by the following chemical structure:
a fable Tail -_
=) Hydrophilic Group
M`lWuhoerroecthheemiRcy.a.l. "tapiolr"t,imoondiisftiheedstinablleengftlhuoarnodcasrtbrouncttuarile,to*mXereetpreensdenutsseanseoeldusb,ilwihziicnghgprroouvpi.desIt tihsetheixsceupntiiqouneal eraescihsits anbcaesitcoatlhlyerrmeaslpoannsdibclheemfoircaitls actatpaacbkilcihtayratcotderriasmtaitciocfaltlhye rfelduuocreocshuermfiaccaelt.enTshiions,falsuowreolclhaesmibceailngpotrhteiomnajoofr difference between these materials and conventional surfactants.
The solubilizing group, nonaqueous systems.
~X is commonly water soluble, but can be designed to be oil soluble for use in
a -- = 2) Oleophilic Group
s`uTrhfeancattaunrtesohfatvheeboeleenopphrielpiacregdrowuhpivcahriaerseaemxtornegmetlhye sfulrufoarcoechaectmiivcealinsuarfnauctmabnetsr.ofBeynvalitreornimnegnitt,s,fliunocrloucdhienmgical many systems which would degrade hydrocarbon or silicone surfactants.
qPuhaylsiitcyalcopnrtorpoelrtuiseesaanvdaimlaatbelreioaln h3aMndlfilnugo.roIcthiesmiicmaplorptraondtutcotsrearmeemprbienrcitphaaltlythtehsoesephpyasriaomcehteemriscnaelepdreodpefrotries
choamvpeonbeenetn.obtSaoimneedpfrroodmucptrsomduacytshathvaet naorenfnloutorhiogchhleymirceafilncedo,mapnodnetnhattsmwahyichhacvoenmtroirbeuttehaton tohneedfeltueorrmoicnhaetmiiocnal
ofthe values. weight, POSF
bOanseedo,bfsleurovreoschaemwiicdaelsr.angTeypiincavlallyuetshefsoer
physiochemical parameters among low low molecular weight chemistries tend
molecular to have higher
iwnatteerrmseodliuabtielsitiynatnhed floorwmeartivoanpoorfpprreosdsuucrtes,thsaonmpeoolyfmtehreisce plroowdumcotlseccuolnatraiwneiingghtthfeml.uorInocahdediictiaolnstaorebeailnsgo likely
intermediates in the degradationofpolymeric compounds.
3M Sulfonyl-based Fluorochemical Products
mTahneuf3aMctpurroedsutchtelfiinneasltchaotmmuesrecPiOalSiFz-ebdaspreoddufcltu.oroInchoetmhiecraclassaesr,e 3suMmmsealrliszaefdlbueolroowc.hemIincsalomwehiccasheas,no3tMh.er
`company incorporates into their final product. `groups are not listed.)
(Product lines using fluorochemicals which contain no sulfonyl
Surface Treatments
Fabric/Upholstery Protector Carpet Protector (High MW
(High molecular polymers)
weight
[MW]
polymers)
PLeaaptehrearnPdroPtaeccktaogri(nHgigPhroMtecWtorPo(lHyimgehrsM)W phosphate esters or high MW polymers)
9
000010
Surfactants (Low MW chemical substances)
Specialty Surfactants
Household Additives
Electroplating and Etching Bath Coatings and Coating Additives
Surfactants
Chemical Intermediates
Carpet Spot Cleaners
Fire Extinguishing Foam Concentrates
Mining and Oil Surfactants
Other Uses Insecticides (Low MW chemical substances)
fSloumoreoocfhtehmeicaPlOsScFandebreiviendtecrhmeemdiisattreisesthaarte3rMelaotrivoeulry cluoswtommoelrescuulsaeriwnemiaghktin(g< o5t0h0erdaflitnoinssh)e.d Tphroedsuects. Such mflaukoeropcrhoedmuicctaslwiinttherumneidqiuaetepsecrafnorbmeancocveaclheanrtalcytebroisutnidcs.to Tahvearmiaejtoyroiftypoofly3mMerifcluhoyrdorcohceamribcoanlsbparcokdbuocneeds ftoor fcloumomreorcchieamliiczaalticoonntaarienuinsgedpoinlysmuecrhsp(oulryemtehraince faonrdmacfroyrltartee)atpmleunstfolfuosruorfcahceemsicaanldamdaitpeartiealss.caFnoprreoxviadmeplseoi,l, tstharionu,gahntdhweaftleurorreosciasrtbaonncemotoiepteyrsoonnatlheapppoalryemlearndlohwoermiengfutrhneisshuirnfgasc.e eSnuecrhgyporfotetchteimvaetperroiadlucttoswfhuinccthitohney are applied.
p`Thhoesp3hMatpeaepsetrerpsrootfeNct-oEr(sFcOaSnEb.e dTihveidoetdheirntcolatswsoisgeanNe-raMleFclOaSsEsAes-oafcrcyhelmaitstericeosp.olyOmneer.claAspspilsibeadsteodpoanper, the tpheerfilnudoirvoicdauarlbopnapmeorieftiyberisn.thTehsiesplroowdeurcetds hsausrftahcee perneevrigoyusglryeadtelsyccroinbterdibeuftfeescttoofthleowheorlidnogutthoefsluorfwacseurefnaecergy of energy liquids such as greases and oils.
Aflsuoprroecvhieomuislcyaldessucrrfiabcteadn,ttshdeifPfOeSrFg-rdeeatrliyvefdrofmlucoornovcehnetmiiocnaall phryoddruocctasrbhoanveansdursfialcitcaonntepsrouprefratciteasn.ts.SuIcnhmost tsyypsest.emsInthseoymaereaqfuareomuosresyesftfeimcsie,ntsuirnfarceedutceinnsgiosnusrfaascleotwenassio1n5ttool1e6vedlysntehsat/eamrecuannrebaecahtatbalienedw.itThhtehese other pfelruomriolclhioenm,icoarllsesusr.faEctqaunatlslynoirmmpaolrltyanptroisdutchee ftahcetsetheatxtcreermteailnyofltohwevsaelufelsuaotroccohnecmeinctarlatsiuornfsaacse alcotwivaesa1g0en0tpsaratrse estvaebnlestarnodngelfyfeocxtiidvieziinngmasynsyteemxs.treTmaebllye h6osstuimlemaernivzireosntmheentfse,atiunrecsluodfinfglusotrroocnhgelmyiaccaildiscu,rsftarcotanngtlsy alkaline and
10
000011
Table 6 Features of Fluorochemical Surfactants
J--
nto
pa Smrsotvehr sgttmsionpbvmrisnsstednTcydsioldns
I
a lcmmtSomtrsstoEvoeeCnTedcShdSsStSsShEcEl
were
S BO m i nr--e--
J
J B Lows srionnRb iin cT nmssiolyoecto rtcliies rn
RevucED WATER SPOTTING
PSR m ms-- tin-- ge-- ddo
st
Th mls pth Sr
ros bsons,
I
BR --
PE ------
eodtiooegsruestacpaeinitoveth gor
P--------
Swonzor moeven fnvers ompoisfiend
Levene J A AAA F Stei amsn marsettseeetmassehn' meres T oepiaT tymtivaemssmtSistas vrwaointnss stamny Crm e Sfomoettes st teihveposrsrhsinteiersew hms TWhweat hEeeA meritevtrid sity mde Low eonceTaaTion B DThommarisesomlal t fioveoonn
000012
1
iMmapnorytaanptp.licMaotrioensofitnevnollviqeumido-rleiqtuihdanorjussotliidr--lliiqquuiiddsiynstteerfmasceasrewehnecroeunstuerrfeadc.e tIennstihoensealcoansees,might be
pinrtoecrefsasc.ialQutietnseioofn,teansiwnetlhleasse csausrefsa,ceatceonmsbioinn,atpliaoynsofaasigsnuiiftiacbalnethryodlreoicnarthbeonwestutrifnagctoarntlecvaenlipnrgoduce
caodmebgirneaetoifowne,tittiins gthwehfilcuhorcoacnhneomticbaelascucrofmacptlainsthwehdibcyherietdhuercetsyptehealsounref.acNeotremnasliolny,,wihnisluecthhea
thhyadtreoacsairlybownetmsataenridalspariedasdsinotnheotrheedruwcitsieonhoafrdthteo
interfacial tension. wet surfaces.
The
net
result
can
be
a
system
Afnoaomtsh.erSuuncihqufeoapmhyssihcaavlecbheareanctfeorrimsutlicatoefd ftlouorersoicshtetmhiecaalcstiiosnotfhehiir gabhiltietympteorfatourrme toorugahg,gryeestsrievseilient fchleammimcaabllsealnidquivda,pocrhse.miTchaelsaenfdoromruglaantiicofnisrehsaovretfooxiucndancdomombenrocxiiaolusapvpalpiocratsiaonndinodsourpsp.ressing
2
000013
