New Methods in Anionic Ring-Opening

Polymerization of Fluoro-Epoxides

and their Application.

By

Chadron M. Friesen † * and Benson J. Jelier†

† Trinity Western University, Department of Chemistry, 7600 Glover Road, Langley, BC V2Y 1Y1, and

Simon Fraser University, Dept. of Chemistry, 8888 University Drive, Burnaby BC, Canada

V5A 1S6,E-mail: chad.friesen@twu.ca

Fluoropolymer 2014, October 13-15, 2014

Langley

Chemistry Department

Trinity Western University

Jack VanDyke Research

Laboratory

Outline

Why PFPAEs?

Challenges in Ring-Opening

Polymerization

Use of HFEs

Polymerization Using Non-

conventional methods

Consumer Applications of

Perfluoropolyalkylethers

Photocurable PFPAEs

Soft Matter 2011, 7, 6404-6407.

J. Am. Chem. Soc. 2008, 130, 5438-5439.

Pharmaceuticals

Microfluidics

De-Icing Coatings

Anti-reflective or Self-Cleaning Surface

Commercial Perfluoropolyalkylethers (PFPAEs)

Fomblin® Y, Galden®:

Fomblin® Z:

Demnum®:

Krytox ®:

Photo-oxidation of Fluoroalkenes

Fomblin® Z

Fomblin® Y

Removal of Peroxide Linkages

PFPAEs:Anionic Ring-Opening Polymerization

The Two Greatest Challenges for Anionic Ring-Opening Polymerization

Molecular weight control

– For chemical resistant materials

– Formation of elastomeric

materials

Inexpensive way to form

telechelic materials

– Allows for improved integration

into other polymeric materials

Anionic Ring-Opening Polymerization:

(Initiation)

HFPO

perfluoroalkoxides

13 of 34

Kostjuk, S. V.; Ortega, E.; Ganachaud, F.; Ameduri, B.; Boutevin, B. Macromolecules 2009, 42, 612–619

Hill, J. T. Journal of Macromolecular Science: Part A - Chemistry 1974, 8, 499–520.

Oxetane

14 of 34

Kostjuk, S. V.; Ortega, E.; Ganachaud, F.; Ameduri, B.; Boutevin, B. Macromolecules 2009, 42, 612–619

Hill, J. T. Journal of Macromolecular Science: Part A - Chemistry 1974, 8, 499–520.

Anionic Ring-Opening Polymerization:

(Propagation)

Long Standing Challenge

Long Standing Challenge(Theory)

CHAIN TRANSFER!!

Hill, J. T. Journal of Macromolecular Science: Part A - Chemistry 1974, 8, 499–520.

INITIATION BEGINS AGAIN!!

Known Method(s) to form

difunctional PFPAEs (telechelic)

Is the Chain Transfer due to

the Metal Cation??

Work by C. J. Willis

Journal of Organic Chemistry (1968), 33(5), 1837-9.

Typical Routes to Perfluoroalkoxides

1)

3)

M.E.Redwood, C.J. Willis. Can.J.Chem, 1965, 43,1893; W.B.Farnham, B.E.Smart, J.Am.Chem.Soc. ,1985, 107,4565

X.Zhang, K.Seppelt. Inorg.Chem. 1997,36,5689 ; Kolomeitsev, A. A.; Vorobyev, M.; Gillandt, H. Tet. Lett. 2008, 49, 449–454

2)

Pip+, NEt3H+

Negative Hyperconjugation

Structure C-F (A) C-O (A)

-CF=O 1.350 1.172

[(CH3)2N]3S+CF3O

- 1.397 1.227

Pip+CF3CF2O- 1.402-1.447 1.230

Pip+(CF3)2CFO- 1.416 1.343

(CH3)4N+FC(O)CF2O

- 1.413, 1.480 1.220

CF3OH 1.32 – 1.31 1.307

Perfluoroalkoxides

Farnham, W. B.; Smart, B. E.; Middleton, W. J.; Calabrese, J. C.; Dixon, D. A. J. Am. Chem. Soc. 1985, 107, 4565.

Huang, C.; Liang, T.; Harada, S.; Lee, E.; Ritter, T. J. Am. Chem. Soc. 2011, 133, 13308.

Uneyama, K. Organofluorine Chemistry; Wiley, 2006.

Perfluoroalkoxides

Perfluoroalkoxides

Perfluoroalkoxide Challenges

Rearrangement can occur

Reactivity to Moisture

Inability to be made in situ (organic reactions)

Fluorides must be anhydrous:

– RbF, CsF, KF, AgF, NEt4F

Starting fluorinated material

– Volatile

– Corrosive

– Toxic

KEEP IT SIMPLE!

What about Non-metal

Perfluoroalkoxides?

What are hydrofluoroethers (HFEs)?

“The -OCF3 group is thermally and chemically resistant to attack by acids, bases,

organometallic reagents and oxidizing/reducing agents” – JOC, 1964

Aldrich, P. E.; Sheppard, W. A. J. Org. Chem. 1964, 29, 11–15

Zhang, S. S.; Read, J. Journal of Power Sources 2011, 196, 2867–2870.

Leroux, F. R.; Manteau, B.; Vors, J.-P.; Pazenok, S. Beilstein J. Org. Chem. 2008, 4

Images from: medicineworld.org, www.rsc.org, and www.wagnermeinart.com.

Li battery co-solventReplacement for

CFCs & HCFCsPharmaceutical

Why Hydrofluoroethers?

Easy to work with (b.p. 34 to 100oC )

Minimal global warming impact

Non-ozone depleting

Low toxicity

Anhydrous

Inexpensive

Viscosity is less than 20 cSt at -120°C

The Nature of the HFE Bond

G. S. Grubbs, II and S. A. Cooke; J. Phys.

Chem. A, 2011, 115, 1086–1091

1.337Å1.436Å

How reactive are HFEs to Bases?

TMEDA DABCO

DUPONT CONFIDENTIAL

33 of 34

HFE Reactivity with 3o AminesSalt Formation

??

Group 15

Kornath, A.; Neumann, F.; Oberhammer, H. Inorg. Chem. 2003, 42, 2894.Hohenstein, C.; Neumann, F.; Kornath, A. Z Naturforsch B B 2010, 65, 1327.

N,N-Dimethylbenzylamine

&

HFE-7000

clear crystals

X-Ray Diffraction

19F NMR (376 MHz) at RT in CH3CN

A

B

C

A

C

Hypothesis ?

Perfluoroalkoxide + n HFPO40 of 34

Perfluorobutoxide Initiator

Long Standing Problem:

Remember?

CHAIN TRANSFER!!

Kostjuk, S. V.; Ortega, E.; Ganachaud, F.; Ameduri, B.; Boutevin, B. Macromolecules 2009, 42, 612–619

Hill, J. T. Journal of Macromolecular Science: Part A - Chemistry 1974, 8, 499–520.

HFPO Polymerization Results

Representative GCM-MS highlighting the chain transfer product (C3F7O-) in red over the desired initiated

polymer (C4F9O-) in blue.

C4F9O-

C3F7O-

42

HFPO Polymerization Results

Example

C3F7O-[CF(CF3)CF2O]n-Rf C4F9O-[CF(CF3)CF2O]n-Rf

Average repeat unit

(n)

Degree of Polymerization

(Range of n) for C3F7O

initial group

% Composition for polymers with C3F7O

initial group

Average repeat unit (n)

Degree of Polymerization

(Range of n) for C4F9O

initial group

% Composition for polymers with C4F9O

initial group

CsF 3.85 0-10 100 0 0 0N(CH3)4

+

CF3CF2CF2O- 1.99 0-4 100 0 0 0

N(CH3)4+ 0.79 0-2 85 0.6 0-1 15

N(CH2CH3)3CH3+ 1.93 1-4 93 2.2 1-3 7

N(CH2CH2CH3)3CH3+ 1.87 0-4 93 2.0 1-3 7

N(CH3)2CH2Ph+1.64 0-4 91 2.06 1-3 9

Polymerization Set-Up

1. Temperature

2. Agitation Rate

3. HFPO Purity

4. Addition Rate

5. Amount of HFPO

6. Solvent Purity

7. Solvent Choice

8. Cation of Initiator

9. Anion of Initiator

Variables

Polymerization Set-Up

Polymerization Set-Up

Polymerization Set-Up

.

CF3CF2CF2O CF

CF3

CF2 O CF

CF3

C

O

O

n

CH3

-82.7

-131.90

-82.1 -145.0

-80.58

-80.58 -132.5

-82.1

unit unitrepeat unit

CF2

CF

Determination of Molecular Weight (Mn)

Rel. Integration: -CF2- at -145ppm = 2.00, -CF- at -131.9ppm = 3.73 Therefore n=3.73

Mn = mass of α unit + n (mass of repeat unit) + mass of ω unit

Mn =185 + 166(3.73) + 159 = 963.18g/mol

Hill, J. T. Journal of Macromolecular Science: Part A - Chemistry 1974, 8, 499–520.

Mn Determination: End Group 19F NMR

GC-MS Analysisn=4

n=0

n=1

n=2

n=3

n=5

n=6

n=7

n=8

n=9

CF3

CF2

CF2

OCF

CF2

O

CF

CF3

CF3n-1

O

OCH3

Method designed for the identification of constituent homologues by GCMS (time (min) vs abundance) -

Agilent 6890N with a 5975 MSD, 70eV EI). Thermal Ramp 15°C/min.

Navg = 3.835 Mn = 980.61g/mol

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MALDI-TOF-MS

n=4

n=5

n=6

n=7

n=8

n=9

n=10

185 166 200

CF3

CF2

CF2

OCF

CF2

O

CF

CF3

CF3n

O

NEt

Et

Li

Improvement with diethylamido (Mn=1364, MW 1384, pd 1.014, DPn=5.86)

LiCl in MeOH

Perfluorocinnamic acid + Sample in 50/50 HFE-7100/MeOH

TARGET PLATE = MTP 384 Ground Stainless Steel

Laser

O

OH

F

F

F

F

F

=perfluorocinnamic acid as matrix

50 of 34

ConclusionQuarternary Ammonium Perfluoroalkoxide Salts

Made simply with HFEs and most 3o Amines

– Anhydrous, but reacts readily with moisture

– Stable at RT

An easy and safe method for an In situ

addition of perfluoroalkoxides to a given

synthetic reaction

Used to track chain transfer in the

polymerization of fluoro-epoxides

Route to difunctional (telechelic) materials

Acknowledgements

22nd WINTER FLUORINE CONFERENCE,

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