공업화학과 / 정보통신소재연구실 / 석사 2 기 이인재 2000.10.16

Hanyang UniversityHanyang University

Information and Communication Materials Lab.Information and Communication Materials Lab.

공업화학과 / 정보통신소재연구실 / 석사 2 기

이인재

2000.10.16

I. Introduction Definition

Properties of fluorinated polymers

Classification

Application

II. General properties of fluorine

III. Fluoropolymers

IV. Fluorinated polymers

Fluorinated Polymers



IntroductionIntroduction

1. Definition Polymer made from monomers containing one or more atoms of fluorine, or copolym

ers of such monomers with other monomers

2. Properties of fluorinated polymers

High thermal stability

Low moisture absorption

Low flammability

Good resistance to most chemicals

Good resistance to oxidation and ageing

Low dielectric constant

Excellent weatherability

Low surface energy



3. Classification

•Organic Fluoropolymer

1)Fluorocarbonpolymer

Perfluoropolymer

Partially fluoropolymer

2) Fluorinated polymer

•Inorganic Fluoropolymer

4. Application

1. Military use. seals for super sonic aircraft, submarine coating, perfluoropolyether liquids as lubricant for bearing in satellites, canopies for supersonic fighter aircraft, heat-resistant shields for satellite and spacecrft coatings.

2. Daily use. Gortex, Scotchard coatings liquid perfluoropolyether, fluoropolymer coatings of skyscrapers

3. As a specialty polymer. cable insulation low flame-spreading low smoke-generating crosslinked fluoropolymer



General properties of fluorineGeneral properties of fluorine

Fluorine atom (F)•High ionization potential and low polarizability

;very weak inter- and intramolecular interactions

•Storng inductive electron withdrawal and polarized +C-F-

;C-F bonds are more ionic and stronger than other C-X bonds

Physical properties1)Saturated fluorocarbon(PFC)(perfluorinated carbon) ;lowest dielectric constant, surface tension, refractive indexes of any liquid at r.t. (nonpolar, extremely low polarizability) ;greater densities, viscosities, critical temp, and compressibilities

2)Partially fluorocarbon(HFC) ;properties fall between fluorocarbon and hydrocarbons

•B.E. Smart in “Chemistry of organic Fluorine Compounds II A Critical Review”, Ed. by Milos Hulicky , p.979, (1995)



1) PFCs•The b.ps of PFCs are similar with those of HCs •Unlike HCs, negligible branching effect on the b.p of PFCs ;This trend of b.ps are due to extremely low intermolecular interactions in PFCs.

2) HFCs •different b.p. patterns•b.p ↑ // dipole moment ↑

Boiling point Surface tension 1) PFCs

;due to weak interaction between , PFCs have the lowest surface tension of any organic liquids and can completely wet almost any syrface

2) HFCs•always greater than PFCs•greater, smaller, or equal to those of HCs. ;depending upon fluorine content



• Dielectric constant

1) The relative dielectric constant of insulatiog materials is the ratio of the capcities of a parallel plate condenser measured with and without material placed between the plates.

2) Due to the polarization of the dielectric.

3) Dimensionless quantity

Polarizability is the ability of an atom or molecule to become polarized in the presence of an electric field.

P=E P:induced dipole moment(polarization)

:polarizability E:electric filed

= e+ i+ o

e : electronic polarizability

i : Ionic polarizability

o : orientational polarizability

• Molar polarization

(Lorentz and Lorentz equation)

-1 M

+2 =

1

3 0

NA = P

M : molar weight: molar density

NA : Avogadro’s number

1.Why is the dielectric constant lowered by the fluorination?

The presence of bulky group between imide linkages may reduce inter-chain electronic interaction.

The presence of fluorine substituents may cause steric changes, resulting in less dfficient chain packing and an increase in the free volume of the polymer, bringing the dielectric constant closer to the value of air, ‘1’.

Fluorine may effect a decrease in the electronic

polarizability due to its strong electron

withdrawing inductive effect.



Polarization effects of Fluorine on the Relative Permittivity

G. Hougham et al, Macromolecules, 27, 5964, (1994)

•Change in the electronic mode → Change in the dielectric constant

•Change in the atomic mode → Negligible

•Change in the dipole orientation mode → Nonsymmetric substitution is always positive



The relation between free volume and dielectric constant

•Gareth Hougham et.al., Macromolecules 29,3453, (1996)

Density and fractional free volume

polymer density FFV

6FDA- PDA 1.44940.0008 0.37360.0000346

6FDA- TFPDA 1.5305 0.3832

6FDA- DAT 1.43160.005 0.36750.0022

6FDA- TFMPDA 1.49560.00956 0.38070.000396

6FDA- 2PDA 1.4250 0.3574

6FDA- 2TFMPDA 1.50210.0019 0.39960.00076

Percent of change in Dielectric constant due to change in FFV.

polymer pair % due to FFV

(6FDA- PDA) (6FDA- TFPDA) 2520

(6FDA- DAT) (6FDA- TFMPDA) 4931

(6FDA- 2DAT) (6FDA- 2TFMPDA) 9412

From the previous tables, we can notice

that the the dielectric constant is decreased by

the fluorination whereas the free volume of

polymer is increased



2.Why is the heat-resistance improved by the fluorination?

지방족 탄화수소와 고분자에서 C-H, C-F 의 해리에너지를 비교해 보면 ,methane 에서 C-H, C-F 의 비교 1)CH4, CF4

C-H (104kcal/mol) < C-F (130.5kcal/mol) 2)CH3F, CF4

C-F (CH3F,108.3kcal/mol) < C-F(CF4,130.5kcal/mol) 즉 , 같은 구조에서는 C-H 보다 C-F 의 결합이 더 강하고 , fluorination 의 정도가 클수록 강한 결합이다 .

Ethane 에서 C-H, C-F 의 비교 CH3-CF3 에서 보면 , C-H (106.7kcal/mol) < C-F (124.8kcal/mol)

Polymer 의 경우 ( C-C 비교 ) PTFE 의 C-C 결합이 PE 의 C-C 결합보다 8kcal/mol 더 강하다 .

이상에서 fluorination 에 의해 C-C 및 C-F 의 강한 결합이 유도되므로 고분자의 내열성이 증가한다고 볼 수 있다 .



FluoropolymersFluoropolymers

Historical Background•1938 PTFE 를 DuPont 사의 R.P.Plunkett 에 의해 발견•1943 원자폭탄에 사용되는 우라늄 동위원소 를 분리하는 장치로 처음 사용 독일 (I.G.Farben) 에서 개발된 PCTFE 가 별도로 연구•1944-1947 상업적 용도로 영국 I.C.I 에서 pilot 규모로 생산•1954 Kel-F(VDF/CTFE)

TFE Tetrafluoroethylene CF2=CF2

VDF Vinylidene fluoride CF2=CH2

HFP Hexafluoropropylene CF2=CFCF3

PMVE Perfluoromethylvinylether CF2=CF-OCF3

PPVE Perfluoropropylvinylether CF2=CF-OC3F7

CTFE Chlorotrifluoroethylene CF2=CH2

E Ethylene CH2=CH2

P Propylene CH2=CHCH3

Monomers used in fluoroplastics

Morphology TypePartially

fluorinated

Perfluorinated

Crystalline Resin ETFE PTFE

PVDF PFA

PVF FBE

THV MFA

ECTFE

Amorphous

Resin PFEVE CYTOP

Teflon AF

Elastomers FKM KALREZ

AFLAS

Categories of Fluoropolymers.

•Eunsil Han and Bumjae Lee, Prospectives of industrial chemistry, 2, 23, (1999)

ETFE=E/TFE, THV=TFE/HFP/VDF, ECFE=E/CTFE/other, PFEVE=CTFE/PPVE, FKM=Vinylidenefluoride fluorocarbon elastomer, PFA=TFE/PPVE, FBE=TFE/HFP/PPVE, FEP=TFE/HFP, MFA=TFE/PMVE, CYTOP=poly[perfluoro-butenyl vinylether(BE)], Teflon AF=TFE/2,2-bistrifluoromethyl-4,5-difluoro-1,3-dioxole, AFLAS=TFE/PP alternating elastomer, KALREZ=TFE/PMVE perfluoroelastomer



Polytetrafluoroethylene(PTFE)

C C

F

F

F

Fn

PTFE 수지의 장점

•우수한 화학적 저항성

•넓은 사용온도 범위에서의 열적 안정성

•비접착성 표면 특성

•높은 dielectric strength 를 지니면서 낮은 dielectric loss

•초순수한 고분자

PTFE 수지의 단점

•낮은 creep 저항성 (cold flow)

•어려운 weldability

•어려운 용융가공성

•“Fluorine Chemistry : A comprehensive Treatment”, Ed. by Mary Howe-Grant, p.381, (1995)•J.S.Forsythe and D.J.T.Hill, Prog.Polym.Sci., 25, 101, (2000)

Polyvinylidene fluoride(PVDF)

C

H

H

C

F

F

C

H

H

C

F

Fn

PVDF 수지의 장점

•우수한 기계적 강도 , 강인성 및 내마모성

•낮은 가스 및 액체 투과성

•우수한 열안정성

•저연소 및 저발연 특성 , 고온에서의 creep 저항성

•우수한 용융가공성 , 내화학적 저항성 ( 단 Ketone, amine, amide 에는 용해 )

•우수한 UV 및 방사선 저항성 , 내후성

•초순수한 고분자

PVDF 수지의 단점

•낮은 충격강도 및 파단신율

•화학적 응력 균열 , 불투명성 , 유연성 부족



Meltprocessible perfluoromolymer



Fluorinated polymersFluorinated polymers

1. Requirement of properties

•가공성•공정상의 열적 , 화학적 및 기계적 성질 우수•제조 후 제품의 형상유지에 필요한 충분한

기계적 성질•절연성 ( 유전상수가 낮을 것 )

Fluorine, 주로 – CF3 group 을 고분자의주쇄나 측쇄에 함유

•내열성의 현저한 감소없이 고분자의 용해도를 증가

•유전상수의 감소 및 흡수율의 저하효과

PolyimidePurpose 1)improve solubility

2)reduce of dielectric conatnt

N

C

CF3

CF3

N O

O

O

O

O

C

CF3

CF3

O

CH3

CH3

CF3

CF3

H3C

H3C

CH3

CH3

O

C

CF3

CF3

O

O

O

O

O

Cl HO NO2 OO2N NO2

OH2N NH2

O2N

+

+

n

Du Pont 에 의해 microelectronics 용으로 제조

유전상수 2.9 흡수율 2%

열팽창계수 60ppm/℃ Tg 290℃

2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride(6FDA) 와 oxydianiline(ODA) 의 중합

1)

•Sang Youl Kim, Polymer Science and Technology, 3, 36, (1992)•Shigekuni Sasaki and Shiro Nishi in “Polyimide”, Ed. by GHOSH and MITTAL, p.71, (1996)



N

C

CF3

CF3

N C

O

O

O

O

n

CF3

CF3

2)

Hoechst Cellanese (Sixef polyimide)

유전상수 2.65 Tg 322℃

흡수율 1.1%

2,2’-bis(4-aminophenyl)hexafluoropropane

(4,4’-6FDA) 와 6FDA 의 중합

N

C

CF3

CF3

N C

O

O

O

O

CF3

CF3

O O

n

3)

Ethyl (Eymyd)

유전상수 2.92 Tg 331℃

열팽창계수 55ppm/℃

2,2-bis(4-aminophenoxyphenyl)hexafluoropropane

(4BDAF) 와 6FDA 의 중합

CF3

H2N O

CF3

CF3

O NH2

F3CF F

F F

H2N NH2

O OH2N NH2

O OH2N NH2

NH2

OCH2(CF2)CF3

NH2

F3C

O

CF3 CF3

H2N NH2

F

F F

I II

III IV

V VI



•Fluorinated polymer system

Low dielectric constant, high thermal stability

Low moisture absorption

•Benzoxazole polymer system

High Tg(>400℃)

•Results

Journal of polymer science:Part A:Polymer Chemistry, 38, 1991-2003, (2000)

CF3

CF3

H2N

HO

NH2

OH

A

B

HOOC COOH

CF3

CF3

HOOC COOH

N

O

CF3

CF3

O

N

O

N

CF3

CF3

O

N CF3

CF3

and/or

+

A

Bx y

2-Hydroxyterephthalic acid/Dihydorxyterephthalic acid

2,2-Bis(3-amino-4-hydroxyphenyl)hexafluoropropane

2,2-Bis(4-carboxyphenyl)hexafluoropropane

•Fluorinated Benzoxazole Polymer



Ar OH + n KOH Ar O-K+

n n

Ar O-K+n + n BrCF2CF2Br Ar OCF2CF2Br

n

Ar OCF2CF2Brn

+ n Zn Ar OCFn

CF2

Synthesis of monomer

Synthesis of polymerCH3

CFO OCF

OCF

F2C CF2

CF2

CH3

O

O

FF F

F

OFF

F

F

F

FO F

n

Journal of Polymer Science:Part A:Polymer Chemistry, 31, 3465, (1993)Macromolecules, 29, 852, (1996)Mat. Res. Soc. Symp. Proc, 443 ,21, (1997)

Poly(1,1,1-triphenylethane perfluorocyclobutyl ether

•Perfluorocyclobutane Aromatic Ether Polymer •Parylene AF-4

•Dielectric constant : 2.2~2.3

•Dissociation : 530 ℃ in N2

•Thickness vs Annealing Temp : no change to 500℃ in N2

•Structure As Deposited : Crystalline/Amorphous

공업화학과 / 정보통신소재연구실 / 석사 2 기 이인재 2000.10.16

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Transcript of 공업화학과 / 정보통신소재연구실 / 석사 2 기 이인재 2000.10.16