k DA9 051 POLYMERIZATION OF FLUORINATED DIACETVLENES(U) vs1IFLUOROCHEN INC NZUSR CA K MUMJ ET AL. If NOV 07T-I NM14-04-C-0386

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4 PERFORMING ORGANIZATION REPORT NUMBER(S) 5 MONITORING ORGANIZATION REPORT NUMBER(S)

Technical Report No. 4

6a NAME OF PERFORMING ORGANIZATION 6b OFFICE SYMBOI 7a NAME OF MONITORING ORGANIZATION

Fluorochem, Inc. (if applicable)

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680 S. Ayon AveAzusa, CA 9t702

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11 TITLE (Include Security Classification) 413 ; !'T ------

Polymerization of Fluorinated Diacet-y'enes

12 PERSONAL AUTHOR(S)

Kurt Baum, Paul G. Cheng, Ronald J. tHunadi and Ciifford 1). Bedford?)a TYPE OF REPORT 13b TIME COVERED 14 DATE OF REPORT (Year Month. DayI 5 PAGE COUNT

Technical FROM TO 1.)87 Nov. ,0 ,16 SUPPLEMENrARY NOTATION

To be published in the Journal of Polymer Science

17 (OSATI CODES 18 SUBJECT TERMS (Continue on reverse it necessary and identify by block number

FIELD GROUIP SUB-GROUP ;o I ymer;, F'I urocarbons, Aeet,v lenes bo "

19 ABSTRA ntinue on reverse if necessary and identifv bv block ioumber) S R ,...'

PterfuJoto iJkyIh 'r (w iu i',; fy , ,, fC(: -(e' ),-vu (II, iriherw erit th.rI 11, l C TAB e(

polymerization at 250-350 oC to !,Yivt, flassy ptymtCrs -,i hie to 450 .It tio _.

Par tia l polym erizti ()n of ht, v(,t u ti I-. HIl)l llltlo , r s o ()ve rsm l'S that nre -

I)WtOCR'HSS;ith, I-t. AtTo'q)|fleri( , ist'tr-o. 1Polyitle ra with iimilar thermal Iallablllty C 06

st.bilit.y wert; ,t)liiirlet( hy ofr Ii irrlI('IliI $cif:ily',.,d ly(i'.1-fi~n of t SpeolaL

tho monomers at Itoderh-t, te-mrn w'ntume.,. .

20. DISTRIBUTION/AVAILABILITY OF ABSTRACT 21 ABSTRACT SECURITY (LASIFICATION

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DD FORM 1473,84 MAR 83 APR e(fition may be wwki uritI Idt, hu 'd eT Y (tA ASIFICATiOr OF T IS PA FAlI Otho-r editions ate oh oAete

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Polymerization of Fluorinated Diacetylenes'

Kurt Baum, Paul G. Cheng, Ronald J. Hunadi and Clifford I). Bedford

Fluorochem, inc., Azusa, California 91702

Synopsis

Perfluoroalkylene diacetylenes, HC-C-(CF2)n-,-CCll, underwent thermal

polymerization at 250-350 OC to give glassy polymers stable to 450 OC.

Partial polymerization of the volatile monomers gave oligomers that are

processable at atmospheric pressure. Polymers with similar thermal

stability were obtained by transition-retal-catalyzed polymerizfl, io of

the monomers at moderate temperatures.

INTRODUCTION

There has been extensive interest in recent years on the application

of acetylene-terminated monomers and oligomers for the preparation of

thermally stable polymers. Systems that have been studied include poly-

phenylene82 , imides3 , phenylquinoxalines 4, sulfones s and triazines6 . The

acetylene groups undergo thermal polymerization to give linking groups

with high thermal stability.

Fluorocarbons comprised another structure class taint tippear(d t.o be

potentially useful for this approach. Fluoropolymers possess useful

stability, dielectric, and wat~er re p;lerncy properties, but. mithods for

the preparation of cross-linikled, 'astable matrices are not generally

available. With the objective of providing slarting materials for this

purpose, we developed synthesis procedures for perfluoroalkylerle diacety-

lenes, jlC=C(CF 2),C-CI. 7 '' he preferred synthetic rou t(e for HC-C(CF2)4Cl(l1

and higher hornologs is outlined below.

CF2"CF2 + I2 -- > I(CF2 )Tul

I(CFa)nl + MeaSiCzCSiMeC ..... Me: Si(_C(CF;)r,(':-CSiMea

MeaSi.C=C(CF2)nCECSiMe3 + KF -.....) HCzC(CF2)nC=Cll

The preparation of HC-C(CF2)6C-C(l by this method was complicated by. the

formation of a cyclic product, and art alternate procedure consisting of

addition of the fluorocarbon diodide to trimethylsilylacLttylene,

dehydrohalogenation and desilylation was used. 7

EXPERIMENTAL

Proton and fluorine NMR spectra were )btjinod with a Varin T-60

spectrometer. Mass apecLra were obtained uting a AEI MS-9 instrument.

Molecular weights were obtained with a Mcchrolab vapor phase osmorieter.

Elemental analysis was carried out by Galbrnith ArialyLical Laborit.ory,

Hnoxville, Tenn. or ;;jang Micronralytical [,aboraL, ry, Eagle Harbor, Mich.

Perfluoroalkylene diacetylenc were prepared by the provcdures reported

previously.7

1 I- Perfluoro- 1-dodecyne

A mixture of 100 g (0.155 mol) of perfluorodecyl iodide and 58 g

(0.34 mol) of bis(trinethylsilyi)acetylene was sealed in a heavy-wall

glass ampule and heated at 220 Ot: foi- 48 It. )istillation I,'ave 60 g of

crude l-(trierothylqilyl)perfluoro- l-dodecyne as a red oil, bp 150-160 0 C

(2 mm). This material wns ntirr.d with 100 11- of pottumiu, fluoride

dihydrate in 400 ml, of mothariol for 16 h. ''he mixture was diluted with

200 mL of saturated sodium chloride solution nrid was :x~racted with 500

mL of ether. The other solution wa. dried ovr magnesium sulfate and

distilled to give 25 g (30% based on perfluorodecyl iodide) of Ill-per-

fluoro-l-dodecyne, bp 35 0 C (2 mm), imp 24-25 "(): 11l NMIR 9 2.95 (L, J F

5 liz); 1F NMR 0 86.2 (t, 3 V, .1 = 10 10z, CO'>), 103 (in 2 F, CI.zC.C), 123-

• -- . , j ., ,, .., , , , , -,... -, - .- - -.. 5'.. .',.,'.,' ,-.'.'.' ' '.,'.',* : : : -,,.'I

126 (uit, 14 F, CFO), 129 (0), 2 P', CP-;tCF1).

Anal. Culccd for' C12J1112. (7, 26.49; If, f). 19. Foullno; i", H .';i.

0.16.

Thermal Oligomotrization of 1 1-Pe~rfluorodocev' not

I Il-Pe.rfiunoro- I-dJe]c(-y ii, (2.0 g, 3.7 nitl)wa.s net'. o 01I f! trlutj ;:I t

and heated at 260 O'C frI 40 It. ';tlbIi l1LktjOZI01 t h! lIIixte i~d tit 100 0-,

(0.1 fin) giavo i.1 g ( 1573%) c1 t white H.WI p u*j2OC: ;i1 hh -

(lii); "IF' NM W 8f;.o (. t, , . 0) V2., K , 1..-1''r~

126 (mn, 14 P, CF.-), 1?2 ) (tan, 2 1 :~'j n~i~fciat. . 7' 0'1 r

unr INP - (e1.'2 ).CF'j); M"' (VPU., "LLVI t''.~')t~~ u 4~i~ I 1C.;

fotir,.d: 2490.

0.17.

1 1-1P rf luorcl- 1-0,tf docyrte- (;) 1,, 1.8 woata as ii.:i,f % l %j1 h a *

bis4(ber/ortijfl) )Jiulid LUri) (! h .AVft. a i )I vbl!-tttliw~ :I,.! I'itct. 1

110 O1 for ), i. Thc ra't;t!tfirig, viF~aaoul4 kuO tIn- diih-4(lv((i itt1,,2

ti Ichlorot!'it tir~ ~and ft icelod I o ron:' thO 7tildyst.f~ o

tiori of the Rolvc-iI. -1I!vi g.: ~: of'v~;u oil: 'it NMvi? i, '.(w(t);

91-' NMR 0 ht. (t, 0 ~, 1 - 10 !It,,FO IP 2 F, il';-C), l41

(ti, 14 1-', CVl'), 121) (Ii, 2 F, w' :w.s *:'etrujIa Fi/(! l,I3 (tvnilw* NI,

F) )G3) (triw.'J,~?~~?)') t, 'V () 1,),2-trichlort '-iflau.au

o't hnr.o) cal;ed forC*iIFei 16382; F I..'. 148,;

Atia. (C;jric (3,: C i~f, 1 i, C ;, 0.I) * i .: 26 .4", hi

0.22.

W 0

Thermal Oligomerization of IH,12H-Perfluoro-1,11-dodocadiyne

A sealed glass tube containing 0.41 g (0.9 mmol) of l1,12H-per-

fluoro-1,11-dodecadiyno was heated at 250 OC for 41 h. Unreacted

starting material was removed under vacuum to give 0.28 g (68%) of

viscous oil: MW (VPO, ethyl acetate) calcd for tetramer C48HsF&.: 1800;

found 1726. Heating the material at 260 QC for 40 h gave a yellow glassy

polymer insoluble in common solvents.

Catalytic Polymerization of 1H, 12H-Perfluoro- 1,11-dodecadiyne

A mixture of 2.0 g (4.4 mmol) of 1H,12H-Perfluoro-1,1l-dodecadiyne

and 10 mg of bis(benzonitrile)palladium (11) chloride was heated in a

sealed glass tube, with occasional shaking, at 120 OC for I h. A brown

rubbery resin was obtained. An identically prepared sealed sample heated

for an additional 12 h period at 150 0C gave a dark glassy polymer.

RESULTS AND DISCUSSION

Preliminary thermal polymerization studies of the fluorinated di-

acetylenes were carried out using l1C=C(CF2)eC-CH, H0_C(CFs)sC=CH and

lC=C(CFa)ioC=CH. Samples were heated in scaled tubes at 250 0C tW give

clear hard polymers, yellow to amber in color. DSC analysis of the

samples showed symmetrical exotherms at 350 OC, with no evidence of

decomposition to 450 0C. Repetition of the scans showed only ondotherms

at 106 to 120 0C, believed to represent glass transition temperatures.

TGA showed initiation of woig~ht loss at 450 0C. The 350 0C exotherm was

ascribed to the completion of polymerization of uricured sites, confirmed

by the observation of acotylenic aimorbtion in the IR spectra (3318 and

2145 cm - 1) of the original polymer. The iI(>C(CF2abC-CH polymer showed a

critical surface tension of 21.6 dynoa/cm, and water absorbtion determi-

4

nation over a 6-month period was negative. A swelling experiment with

Freon 113 showed 12% absorbtion in 90 hrs.'

Because HC-C(CF2)sC-CH is more readily available in quantity than

its homologs, and this material was used in subsequent work. A problem

in practical applications of this diacetylene is that its volatility at

the temperatures required for thermal polymerization would require the

use of pressurized containers for the fabrication of samples. One way to

circumvent this problem is to carry out. the polymerization in sealed

containers to only a low degree of completion with the objective of

preparing fluid or easily proceEiable oligomers with sufficiently low

volatility that final cure can be carried out at atmospheric pressure.

The polymerization of HC=C(CF2)sCZCH was controlled adequately at

250 OC in sealed tubes, and after 41 It, 68% of the monomer was consumed.

Removal of the unreacted monomer under vscuum left a viscous oil with a

VPO molecular weight of four monomer units. The oligomer was then cured

at atmospheric pressure by heating at 250 OC for several days to give a

polymer with similar appearance and thermal properties to that obtained

by polymerization of the monomer in sealed tubes.

Another approach to applying the volatile diacetylene for molding or

coating applications is to use catalysts to lower the polymerization

temperature. The cyclotrimerization and oligomorization of 3,3,3-tri-

fluoropropyno with metal carbonyl catalysts has been r(eported, 10 and a

number of catalyst systems have been used for similar reactions of non-

fluorinated aromatic and aliphatic ncetylenv.s4.1 Consequontly, we

initiated qualitative scroenir, stiidies to determine the offectiveness of

some available catalysts for th, polymerizition of IIC.:C(CI"2)mC--CII. The

results are summarized in Table I.

- - -- - - - - - - - - - - - -l F - -- - - -a t - - - - - - - - - - -~r O - - - - - - - - - -

Table 1. Catalyst Screening

Conditions: 1 wt% catalyst heated with HC=C(CF2)aC=CH 4 brs at 140 00+e sample solidified; + sample became viscous; - ro changeCp cyclopentadienyl; acac =acetylacetonate

Catalyst Result1CpTiBr2CpTiJ~rz/NaBH4Cr(aCaC)3CpMo(CO)2PPh3* Cl-

Mo(CO)6++CeHr6W(CO)3 +FeCp(CO)2 IFe (acac) 3Co( acac) 3CPCO(CO)2PdC12 (PhCN) 2 ++

'aNi(acac)2 ++

Ni(CN)2NiBr2-PPh3 +

NiBr2 -PFh3-N aB 114 +Ni (CN) 2 -PPh3 -N11114 +

NiBr2.NaB14NiI2'PPH3i 4

Of the catalysts tested, IPdCI2(PhCN)2 was the miost effective, and an

little as 0.1 wtV. was sufficient to promoto polymerization. With a 1%

catalyst level, solidification took place in 2 days at ambient tempera-

ture, in 2-3 lira at 80 OC and in minutes at 130 OC. The catalysts,

Ni(acac)2 and Mo(CO)G were lesm effective than PdCI2(PhCN)2, but they

also produced polymers with appearance similar to that of the thermally

produced polymer. On the other hand, Ni(Ph3P)2(CO)2 and CpCo(CO)a gave

tarry products. Because of the effectiveness of PdCla(PhCN)t for our

* system, further work was carried out with this catalyst, which has been

reported to trimerize ulkynes selectively to benzeiies. 12

Cured samples of the catalyzed polymer were similar to those pro-

duced thermally in that they had a glassy ap;pearance and were brittle.

DSC curves of the two types of polymner were essentially identical. To

6

obtain additional information about the polymeriaztion reactions, model

studies were carried out using CF3(CF2)oCCH. Heating a sample of this

monoacetylene with PdClz(PhCN)t at 110 0C for 5 h gave a 95% yield of an

oil, identified by molecular weight, elemental analysis, and mass spec-

troscopy as a trimer of the starting material.

Also, CFs(CF2)gCCH was heated under conditions used for the thermal

polymerization of the diacetylenes, 260 OC for 40 h. The product was a

sublimable solid with a molecular weight by VPO of four monomer units.

The brittleness of the polymers is attributed to the high degree of

cross-linking, and would be expected to be lessened by copolymerizing a

monoacetylene with the diacetylene. Mechanical properties of the palla-

dium-catalyzed homopolymers arid several copolymers were determined by the

three-point bending method 13, and are summarized in Table II. Copolymers

of HC-C(CF2)aC=Cl1 wore obtainod with PdCI2(PhCN)2 as the catalyst and

CF3(CF2),CCH as the monofunctional conmporient. A sample basled on 28 mole

% monoacetylene was a hard resin similar to the diacetylene homopolymer,

but somewhat less brittle. lowever, a sample prepared with 57 % of the

monoacetylene was flexible and rubbery. Tensile moduli of the copolymors

and the homopolymer are in agrRcrment with these observations.

Tensile moduli for the homopolymer at temperatures to 200 0C were

also determined. There is no significant discontinuity at the tempera-

ture of the DTA endotherm (118 0C).

Table 11. Tensile Moduli

Mole % Monoacetylene 0c Tensile Modulus (kglcm 2 )

0 25 92028 25 79657 25 63

0 100 550 f0 130 4H00 200 540

7

S Ile

RE FERE NCES

1. This work was supported by the Office Of Naval Research.

2. I1. Jab]oner and 1. C. Cessna .7. Elustomers Past., 6, 103(1974).

3. A. L. Landis, N. Bilow, R. 11. Boshan, R. R. Lawrence and T. J.Aponyi, Polym. Propr., Am. Chem. .Scx., Div. Polym. Chem.,15(2), 533 (1974).

4. F. L. Hedberg and F. E. Arnold, J. Appl. Polyni. Sci., 24, 763(1979).

5. M. G. Maximovich, S. C. Lockerby, F. E. Arnold and G. A. Loughran,Sci. Adv. Mater. Process Eng. Ser., 23, 490 (1979).

6. P. M. Hergenrother, Macromolecules, 11, 332 (1978).

7. K. Baum, C. D. Bedford and R. J. Hunadi, J. Org. Chem., 47, 2251(1982).

8. DSC arid TGA tests were (arried out. at Wright Patterson Air ForceBase under the direction of Dr. F. L. Hedberg.

9. We are indebted to Drs. J. Griffith and A. Snow of the NavalResearch Laboratory for the critical surface tension, moistureabsorbtion and Freon swelling experiments. See: S. J. Shaw, 1. A.Tod and J. R. Griffith, Proc. of Polymer Science and Engineering,56, 207 (1987).

10. R. S. Dickenson and 1). B. W. Yawney, Aust. J. (hem., , 20, 77,(1967).

11. R. FukB and H. G. Viehe, "Cheitry of Acetylenes", 11. G. Viehe,Editor, Marcel Dekkor, N. Y. (1969). W. Roppo and W. J.Schweckondic:k Ann. C hem., 560, 104 (1948).

12. M. Avram, E. Avram, G. I). Mateecu, I. G. Dinulescu, F. Chiraleu,fnd C. 1). Nonitzcscu, (Cham. 11cr. 1969, 102, 3996. M. Avram, 1. G.Dinuslescu, G. D. Mateemcu and C. D. Nenitzescu, Rev. Roum. Chem.,14, 1191 (1969).

13. We are indebted to Dr. Roger Porter and Mr. Steven DeTeresa,University of Massachusetts, for the me-chanical property teats. Anlnstron Universal Testing Machine. was used for the three-pointbending test.

ABSTRACTS DISTRIBJTION LIST, 3568

Professor A. G. MacDiarmid Dr. Richard M. LaimeDepartment of Chemistry SRI InternationalUniversity of Pennsylvania 333 Ravenswood AvenuePhiladelphia, Pensylvania 19174 Menlo Park, California 94025

Dr. E. Fischer, Code 2853 Dr. L. BuckleyNaval Ship Research and Naval Air Development Cnr)'er

Development Center Code 6063Annapolis, Maryland 21402 Warminster, Pennsylvaria IS974

Professor H. Allcock Dr. James McGrathDepartment of Chemistry Department of ChemistryPennsylvania State University Virginia Polytechnic InstituteUniversity Park, Pennsylvania 16802 Blacksburg, Virginia 24061

Professor R. Lenz Dr. Geoffrey LindsavDepartment of Chemistry Chemistry DivisionUniversity of Massachusetts Naval Weapons CenterAmherst, Massachusetts 01002 China Lake, Califcrnia C.,5

Professor A. Epstein Professor C. AlenDepartment of Physics Department of ChemistryOhio State University University of VermontColumbus, Ohio 43212 Burlington, Vermont 05401

Dr. J. Griffith Dr. William TollesNaval Research Laboratory Code 6100Chemistry Section, Code 6120 Naval Research LaboratoryWashington, D.C. 20375-5000 Washington, 2.. ?0375-000

Professor G. Wnek Professor T. KatzDepartment of Materials Science Department of Chemistry

and Engineering Columbia UniversityMassachusetts Institute of Technology New York, New York 1002-Cambridge, Massachusetts 02139

Professor J. SalamoneDr. Samson Jenekhe Depdrtment of rhem'istryHoneywell Corporate Technology Center Uriversity o Lowell10701 Lyndale Avenue South Lowell , 'lassachusetts 0!.54Bloomington, Minnesota 55420

Dr. B. Gordon IITProfessor William R. Krigbaum Department of Materials ScienceDepartment of Chemistry Pennsylvania State UniversityDuke University University Park, PA 16802Durham, North Carolina 27706

Dr. P. MillerIvan Caplan Almaden ResearJh CenterDTNSRDC 650 Harry RoadCode 0125 San Ynse, CA 15120-3099Annapolis, MD 21401

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DL/1113/86/2

ABSTRACTS DISTPIBUTION LIST, 356B

Professor T. Marks Professor J. MooreDepartment of Chemistry Department of ChemistryNorthwestern University Rensselaer Polytechnic InstituteEvanston, Illinois 60201 Troy, New York 12181

Dr. Kurt Baum Dr. V. PercecFI uorochem,J .- - . Department of Macromolecular680 o Avenue ScienceA za, California 91702 Case Western Reserve University

Cleveland, Ohio 44106Professor Stephen WellinghoffDivision of Chemistry and Dr. Gregory Girolami

Chemical Engineerinq Department of ChemistrySouthwest Research Institute University of Illinois6220 Culebra Road Urbana-Champagne, IL 61801Postal Drawer 293110San Antonio, Texas -8284 Dr. Ted tWalton

Chemistry Divisionr. William 5ailp,/ Code 6120

Department of Chemistr, Naval Research LabUniversity of Maryland Washinston D.C. 20375-5000College Park, Maryland 20742

Dr. Thomas J. McCarthyDr. J.C.H. Chien Polymer Science andDepartment of Polymer Science and Engineering Department

Engineering University of MassachusettsUniversity of Massachusetts Aaherst, MA 01003Amherst, MA 01003

Proescor A. HeegerProfessor G. Whitesides Department of PhysicsDepartment of Chemistry University of CaliforniaLarvari niversity Santa 3arbara, California 93106Cambridge, Massachuse+tt 02138

Dr. Fred WudlDr. K. Paciorek )epartment of ChemistryJItrasystems, Ir. University of CaliforniaP.O. 9nx 19605 Santa Barbara, CA 93106Irvine, California 92715

Dr. Ronald ArcherDepartment of ChemistryUniversity of MassachusettsAmherst, Massachusetts 01002

Professor D. SeyferthDepartment of ChemistryMassachusetts Institute- of TechnologyCambridge, Massachusetts 02139

"U ,, %, ' ._ -.-," - -,,,',. " --. ..: -'.. ,'-' , %" ,..,'''' '.>. .:.

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