[acs symposium series] polymeric materials for corrosion control volume 322 || corrosion behavior of...

28 Corrosion Behavior of Epoxy and Unsaturated Polyester Resins in Alkaline Solution

H. Hojo, T. Tsuda, K. Ogasawara, and T. Takizawa

Department of Chemical Engineering, Tokyo Institute of Technology, Ookayama, Meguro-ku, Tokyo, 152, Japan

The effect of temperature and concentration on corrosion behavior and corrosion mechanism of epoxy and polyester resins in NaOH solution were studied, and were discussed by considering their structures.

Resins used were two types of epoxy resins cured with anhydride and amine and iso-phthal ic type polyester res in .

Different behaviors and mechanisms were c lear ly recognized between these res ins . Epoxy resin cured with amine showed no degradation during immersion because of its stable c ross l inks . Epoxy resin cured with anhydride showed the uniform corrosion with the softening and dissolut ion of the surface and also behaved s imi lar to the oxidation corrosion of the metal at high temperature obeying l inear law.

Iso-phthalic polyester resin was corroded with the formation of the color changed surface layer and corrosion rate of the resin were controlled by diffusion process of the solution through the layer. Thus s imi lar behavior was observed to oxidation corrosion of metal obeying Wagner's parabolic law. The difference of behaviors of these resins were mainly due to the posit ion of ester bonds in the structures.

Method to predict the retention of the strength of resins after immersion was also proposed by applying the concept of corrosion mechanism in metal.

F i b e r r e i n f o r c e d p l a s t i c s have seen much s e r v i c e i n ind u s t r y because of t h e i r e x c e l l e n t mechanical and chemical p r o p e r t i e s and a l s o economical point of view. At present c o r r o s i o n r e s i s t a n t f i b e r r e i n forced p l a s t i c s are i n use as la r g e tanks, v e s s e l s , r e a c t o r s and pipes.

Corrosion r e s i s t a n t FRP s t r u c t u r e s and also r e s i n l i n i n g s have r e s i n or r e s i n - r i c h surface l a y e r to protect the s t r u c t u r e s from c o r r o s i v e a t t a c k . Therefore, the study of cor r o s i o n behavior of r e s i n i s e s s e n t i a l l y important.

0097-6156/ 86/ 0322-0314$06.00/ 0 © 1986 American Chemical Society

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028

In Polymeric Materials for Corrosion Control; Dickie, R., et al.; ACS Symposium Series; American Chemical Society: Washington, DC, 1986.

28. HOJO ET AL. Epoxy and Unsaturated Polyester Resins in Alkaline Solution 315

In a l k a l i n e and a c i d s o l u t i o n s , thermosets co n t a i n i n g e s t e r groups are degrated mainly due to the h y d r o l y s i s of the e s t e r s (1-6) But i n case of the r e s i n c r o s s l i n k e d by e s t e r bonds such as some epoxy r e s i n s (7-9), c o r r o s i o n behavior i s though to be d i f f e r e n t from that of the r e s i n which has e s t e r bonds i n the main chain.

In t h i s paper, the e f f e c t of temperature and concentration on c o r r o s i o n behavior and c o r r o s i o n mechanism of epoxy and unsaturated polyester r e s i n s i n NaOH s o l u t i o n were s t u d i e d , and were discussed by c o n s i d e r i n g t h e i r chemical s t r u c t u r e s . Corrosion r a t e s t u d i e s were a l s o made by applying the concept of m e t a l l i c c o r r o s i o n .

EXPERIMENTAL Resins used were two types of epoxy r e s i n s (EP) and an unsatu

rated p o l y e s t e r r e s i n (UP) as shown i n Figure 1. EP i s the b i s -phenol-A type r e s i n cured with methyl-tetrahydrophthalic anhydride (MTHPA) or 1,8-p-menthandiamine (MDA). UP i s the i s o - p h t h a l i c type r e s i n which has ester bonds i n the main chain and i s c r o s s l i n k e d by styrene (10).

F l e x u r a l t e s t specimens were made according to ASTM D790 from casted r e s i n sheet of 2mm t h i c k n e s s .

Test environments used were NaOH s o l u t i o n with various concent r a t i o n s of 10 to 40wt.%. Immersion t e s t s were c a r r i e d out at temperatures of 20 to 104 C f o r up to 3000 hrs, and a f t e r immersion weight measurements and f l e x u r a l t e s t s were performed at room temperature (Testing speed: 2mm/min, Span: 40mm). O p t i c a l and scanning e l e c t r o n microscopes and i n f r a r e d spectroscope (IR) were f u r t h e r used to study the degradation mechanism of the r e s i n s .

CORROSION BEHAVIOR OF EPOXY RESINS (a) Epoxy Resin Cured with MTHPA

Figures 2 and 3 show the weight change of epoxy r e s i n cured w i t h MTHPA (MTHPA-EP) at various concentrations and temperatures. T y p i c a l weight change i s shown i n the curve of 20wt.% s o l u t i o n i n Figure 2.(also see Figure 10). At f i r s t the weight increases and secondly decreases and t h i r d l y again increases remarkably with an increase of immersion time. The l a s t weight gain, however, can be recognized only at high temperature and concentration range. At the f i r s t stage, penetration r a t e of the s o l u t i o n i n t o the r e s i n i s higher than d i s s o l u t i o n r a te of c o r r o s i o n products, thus causing to increase i n weight. At the second stage, d i s s o l u t i o n r a t e i s higher than penetration r a t e , as a r e s u l t weight of the r e s i n decreases. T h i r d l y severe penetration of the l i q u i d i n t o and through the corroded l a y e r causes the marked increase i n weight.

Figure 4 shows the r e t e n t i o n of f l e x u r a l strength of immersed specimens. Strength r e t e n t i o n was defined as the r a t i o of strength a f t e r immersion to o r i g i n a l one. Strength decreases markedly wi t h i n c r e a s i n g temperature and concentration because of the severe c o r r o s i o n .

At the specimen surface, s o f t corroded l a y e r was formed during immersion and the l a y e r could be e a s i l y removed by wiping l i g h t l y with acetone-soaked paper and i n some co n d i t i o n s t h i s l a y e r was d i s s o l v e d spontaneously. The thickness of t h i s l a y e r was defined as c o r r o s i o n depth x, and measured at various t e s t c o n d i t i o n s . As shown i n Figure 5, c o r r o s i o n depth increases l i n e a r l y w i t h time, and

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028


POLYMERIC MATERIALS FOR CORROSION CONTROL

+CCCO<o>C<Q;OCCC-|-

O Q _ £ 0

w c

C C C 0 < O > C < O > 0 C C C T -

o w c

(a) Epoxy r e s i n cured w i t h MTHPA

-c<Ô>°cçcN

-occc OH

Ç H

ccco-

ccco-OH

(b) Epoxy r e s i n cured w i t h MDA

0 I 0

occcco-f

c ç iJJ c 91 9 -+C C 0 C(^)CO C CO c c c c o-h

(c) I s o - p h t h a l i c type unsaturated p o l y e s t e r r e s i n

Figure 1. Chemical struc t u r e s of epoxy and unsaturated polyester r e s i n s .

3 eu 00 c cd υ

-1

-2

-3

τ 1 Γ " —I 1 1

• · Δ • • C L[wt.%] 0 10 20 30 40

A

y y - Δ ^ ·ν

• \ Ν

t 1 1 1 1 1 10 100 1000 Immersion time, t [ hr ]

Figure 2. E f f e c t of concentration of NaOH so l u t i o n on weight change of MTHPA-EP.

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028


HOJO ET AL. Epoxy and Unsaturated Polyester Resins in Alkaline Solution 317

10 100 1000 Immersion time, t [ hr ]

Figure 3. E f f e c t of temperature of 10wt.% NaOH s o l u t i o n on weight change of MTHPA-EP.

ι 1—1

c to 0.8

s- a

J Ï 0 . 6 c

or 0.4

—ι — ι — ι ι — ι —

\ \ \ \ X>

T[°C] C L[wt "O 50 10 fa \ Ο 65 10

- · 80 10 \ Δ 80 20

-V 80 30 -• 80 40

' ' 1 1 10 100 1000

Immersion time, t [ hr ] 10000

Figure 4. Retention of f l e x u r a l strength of MTHPA-EP i n various c o n d i t i o n s .

Immersion 1ime,t C hr ]

Figure 5. V a r i a t i o n of c o r r o s i o n depth of MTHPA-EP with immersion time i n various c o n d i t i o n s .

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028


318 POLYMERIC MATERIALS FOR CORROSION CONTROL

t h i s behavior i s s i m i l a r to that of an o x i d a t i o n of metal at high temperature with the formation of rough, porous oxide s c a l e . This has shown that the concept of co r r o s i o n rate i n metals can be app l i e d even i n p l a s t i c m a t e r i a l s .

Figure 6 shows the IR a n a l y s i s of the s o f t corroded l a y e r

Figure 6. IR spectrum of MTHPA-EP. before immersion, a f t e r 360 hrs immersion i n 40wt.% NaOH at 80 C.

compared with noncorroded r e s i n . In case of the corroded r e s i n , e s ter peak around 1730cm"1 disappears and carboxylate peak appears near 1570cm"1 and 1440cm"1 . This has been proved by the h y d r o l y s i s of the este r s as shown below,

9 9 R-C-0R' + OH" ^R-C-0" + R'OH (1)

Thus, severe corroded l a y e r i s formed because MTHPA-EP has r e l a t i v e short main chain, and these main chains are c r o s s l i n k e d by the est e r bonds.

IR a n a l y s i s of the r e s i n specimen below the corroded l a y e r showed no sig n of c o r r o s i o n , which i m p l i e s that the chemical attack progresses gradually from the surface and also c o r r o s i o n behavior depends s t r o n g l y on higher r e a c t i o n rate shown i n Equation 1 than penetration rate of NaOH s o l u t i o n i n t o the r e s i n , (b) Epoxy Resin Cured with MDA

The e f f e c t of concentration of NaOH s o l u t i o n on weight change of epoxy r e s i n cured with MDA(MDA-EP) i s shown i n Figure 7. Only a small amount of weight gain was observed although a f t e r 3000 hrs immersion. The weight gain, however, decreases with an increase of concentration. The main reason f o r t h i s behavior i s the increase of w e t a b i l i t y as shown i n Figure 8. Figure 9 presents the change of f l e x u r a l strength a f t e r immersion, and i t holds same strength as that of before t e s t i n g even longer immersion at 80 °C. Therefore, MDA-EP i s not attacked by NaOH because of i t s s t a b l e c r o s s l i n k s of C-N bonds.

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028


HOJO ET AL. Epoxy and Unsaturated Polyester Resins in Alkaline Solution

Immersion time, t [ hr ]

Figure 7. E f f e c t of concentration of NaOH s o l u t i o n on weight change of MDA-EP at 80°C.

100

0 20 40 Concentaration[wt.%]

Figure 8. E f f e c t of concentration of NaOH s o l u t i o n on the w e t a b i l i t y to MDA-EP at 80°C.

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028



c 8 l.o £ CO

2 g 0.8

τ — Γ

• Δ • • C L[wt.%] 10 20 30 40 -|

10 100 1000 10000 Immersion time, t [ hr ]

Figure 9. Retention of f l e x u r a l strength of MDA-EP i n various concentrations at 80°C.

CORROSION BEHAVIOR OF UNSATURATED POLYESTER RESIN Figures 10 and 11 show the weight change and the r e t e n t i o n of

strength f o r i s o - p h t h a l i c unsaturated polyester r e s i n (iso-UP). These behaviors show almost the same tendency as MTHPA-EP, however, as shown i n Figure 12 the concentration i n f l u e n c e s f l e x u r a l strength and the strength becomes minimum at the concentration of 30wt%. This behavior i s thought to depend on c o n t r a d i c t o r y tendency of the w e t a b i l i t y and the r e a c t i v i t y with the concentration.

In iso-UP, c o l o r changed r u b b e r - l i k e l a y e r was c l e a r l y observed as shown i n Figure 13. IR a n a l y s i s of the c o l o r changed l a y e r showed the same r e s u l t s of h y d r o l y s i s of e s t e r s as Figure 6. The thickness of hydrolyzed area was measured by IR, and the r e s u l t s agreed w e l l with that of the c o l o r changed l a y e r measured by o p t i c a l microscope as shown i n Figure 14. The thickness of the l a y e r was defined as c o r r o s i o n depth x. Figure 15 shows the v a r i a t i o n of depth χ with immersion time t , and the f o l l o w i n g r e l a t i o n holds,

x 2= k j t or x = k 2 t 1 / 2 (2) where, k j and k 2 are constants.


Figure 10. E f f e c t of temperature of 10wt.% NaOH s o l u t i o n on weight change of iso-UP.

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028



^ 0. 8

3 0

0.4

ι ι ι—ι ι—r—— Α Λ ~

-T L ° C ]

? \ \ \" • 20 _ ο 35 1 \

50 Δ 65 • 80 • 104

1 1 i l I I 1 10 100 1000

Immersion time, t [hr]

Figure 11. E f f e c t of temperature of 10wt.% NaOH s o l u t i o n on r e t e n t i o n of f l e x u r a l strength of iso-UP.

' 1

c 0.8

° • c x

c

0.2

1 ι Ohr S

- VlOlf f / / r -

A 3 0 h y ^ / f

50hi: 70hry

l O O i i r '

1 10 20 30 40 Concentration, CL twt.'/o 1

Figure 12. Retention of f l e x u r a l strength of iso-UP vs. concentration of NaOH s o l u t i o n at 80°C.

Figure 13. Scanning e l e c t r o n micrograph of f r a c t u r e d surface of iso-UP a f t e r f l e x u r a l t e s t . (504 hr, 80°C, 10wt.% NaOH s o l u t i o n )

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028



150

100

s 5 0

1 y 1 1

• IR Ο Microscc pe

Ο

0

I I 200 400

Immersion time, t [hr]

Figure 14. Comparison of the thickness of hydrolyzed area measured by IR and o p t i c a l microscope.

5 t ι ι ι ι ι 1 5 10 50 100 500 1000 5000


Figure 15. V a r i a t i o n of co r r o s i o n depth of iso-UP with immersion time i n various c o n d i t i o n s .

Iso-UP has ester bonds only i n the main chain where h y d r o l y s i s occurs, so a part of r e a c t i o n products from the main chain d i s s o l v e s i n t o the s o l u t i o n . While the c r o s s l i n k formed by styrene remains unaffected because of i t s s t a b l e C-C bonding. As a r e s u l t , the corroded surface l a y e r r e s i s t s the d i f f u s i o n of NaOH s o l u t i o n . This mechanism i s j u s t l i k e an o x i d a t i o n of the metal at high temperature with formation of t h i c k , cohered oxide s c a l e , and can be expressed by s i m i l a r r e l a t i o n of Wagner's p a r a b o l i c law as shown i n Equation 2· The concept of c o r r o s i o n i n metals can be ap p l i e d i n t h i s case too.

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028


28. HOJO ET AL. Epoxy and Unsaturated Polyester Resins in Alkaline Solution 323

PREDICTION OF STRENGTH OF RESINS IN CORROSIVE ENVIRONMENT In MTHPA-EP and iso-UP r e s i n s , the strength of the r e s i n below

the corroded l a y e r of specimen was same as that of before immersion. Assuming that the corroded l a y e r has no strength, the p r e d i c t i o n of strength a f t e r immersion was made by estimating the c o r r o s i o n depth i n the f o l l o w i n g way. (a) Epoxy Resin Cured w i t h MTHPA

Rate of es t e r h y d r o l y s i s depends on both concentrations of ester bonds i n the r e s i n and s o l u t i o n at constant temperature, then

C d x / d t = k 3 C a C 3 (3) Ε L E where Cg i s concentration of ester bonds per u n i t volume of the r e s i n , C L i s concentration of the s o l u t i o n , α and β are order of r e a c t i o n , and k 3 i s r e a c t i o n rate constant. From Arrhenius' equation, k3 i s given as a f u n c t i o n of absolute temperature T,

k 3=A i exp(-E/RT) (4)

From Equations 3 and 4, the c o r r o s i o n r a t e becomes,

dx/dt=A 2exp(-E/RT)C α (5) L Equation 5 i s confirmed by Figures 16 and 17, and from these r e s u l t s χ i s given as

x=A 2exp(-18.8xlO /RT)^' . t (6)

(b) I s o - p h t h a l i c Unsaturated P o l y e s t e r Resin k2 i n Equation 2 was obtained from Figure 15 and p l o t t e d

against r e c i p r o c a l temperature as shown i n Figure 16. The same r e l a t i o n with temperature as that of Equation 4 holds, thus

x=A 3exp(-12.8xl0 3/RT)t l / 2 (7)

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028



Τ = 80 °C

1 5 10 50 Concentration, C L Lmol/U

Figure 17. E f f e c t of concentration on co r r o s i o n rate of MTHPA-EP.

(c) P r e d i c t i o n of Strength a f t e r Immersion The apparent f l e x u r a l strength o^1 a f t e r immersion i s expressed

as ο pi σ ' = ̂ ^ Τ (8)

B 2bh 2

where h, b, and 1 are t h i c k n e s s , width and span of the specimen before immersion r e s p e c t i v e l y .

The true f l e x u r a l strength σ i s equal to that of the o r i g i n a l r e s i n σ » thus Bo

3P 1 On=On = „ , 2 (9) "B ~B 0 2 ( b - ^ x X h ^ x ) '

Equations 8 and 9 give the r e t e n t i o n of f l e x u r a l strength S, c °* (b-2x)(h-2x) 2

s " S . " - b P ( 1 0 )

C a l c u l a t e d values of r e t e n t i o n of strength by Equation 10 f o r MTHPA-EP were compared with experimental values as shown i n Figure 18. Ca l c u l a t e d values were w e l l c o i n c i d e d with experimental values.

As the r e t e n t i o n of strength S v a r i e s only with x > 3 a master

curve can be obtained by p l o t t i n g the terms exp(-18.8xl0 /RT)CL* 5 6-t or exp(-12.8xl0 3 / R T ) t 1 / 2 as shown i n Figure 19. By using these master curves, the r e t e n t i o n of strength a f t e r long term immersion at any temperature and concentration can be pr e d i c t e d .

CONCLUSIONS D i f f e r e n t behaviors and mechanisms of co r r o s i o n were c l e a r l y

recognized i n a l k a l i n e s o l u t i o n between two types of epoxy r e s i n s and a pol y e s t e r r e s i n depending on t h e i r d i f f e r e n t chemical s t r u c t u r e s . Epoxy r e s i n cured with MDA showed no degradation during immersion because of i t s s t a b l e c r o s s l i n k s . Epoxy r e s i n cured with MTHPA showed the uniform c o r r o s i o n w i t h the d i s s o l u t i o n of the surface, and the r e s i n behaved s i m i l a r to the o x i d a t i o n c o r r o s i o n of metals at high temperature obeying l i n e a r law. On the other hand, i s o - p h t h a l i c unsaturated p o l y e s t e r r e s i n was corroded w i t h the formation of the c o l o r changed r u b b e r - l i k e surface l a y e r . Thus c o r r o s i o n r a t e of t h i s r e s i n was c o n t r o l l e d by the d i f f u s i o n of the

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028



Figure 18. Comparison of experimented r e s u l t s with c a l c u l a t e d r e s u l t s f o r r e t e n t i o n of f l e x u r a l strength of MTHPA-EP.

Figure 19. Master curves to p r e d i c t r e t e n t i o n of f l e x u r a l strength of MTHPA-EP and iso-UP.

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028



s o l u t i o n through the l a y e r , and was s i m i l a r to the o x i d a t i o n c o r r o s i o n of metals at high temperature obeying Wagner's p a r a b o l i c law. Therefore, the concept of c o r r o s i o n mechanism i n metals can be ap p l i e d a l s o to the p l a s t i c m a t e r i a l s . F i n a l l y , i n order to p r e d i c t the strength of the r e s i n a f t e r immersion, master curve i n c l u d i n g e f f e c t s of temperature and concentration of s o l u t i o n was proposed by applying c o r r o s i o n r a t e concept as i n metals.

Literature Cited 1. K.H.G. Ashbee, F .C . Frank, F .R.S . and R.C. Wyatt, Proc. Roy.

Soc. 1967, A300, 415. 2. C.M. Vetters, Proc. 25th Ann. Tech. Conf. RP/Comp. D i v . , SPI,

1970, 4-B. 3. R.C. A l l e n , Proc. 33rd Ann. Tech. Conf. RP/Comp. Ins t . , SPI,

1978, 6-D. 4. H. Hojo, K. Tsuda & M. Koyama, Proc. 3rd Int. Conf. in Coating

Sci. Tech. (Athens), 1977, p.221. 5. H. Hojo, K. Tsuda, Proc. 34th Ann. Tech. Conf. RP/Comp.Inst.,

SPI, 1979, 13-B. 6. H. Hojo, K. Tsuda, K. Ogasawara & K. Mishima, Proc. 4th Int.

Conf. on Composite Materials (Tokyo), 1982, p.1017. 7. R.F. Fisher, J. Polym. Sci., 1960, 44, 155. 8. Y. Tanaka & H. Kakiuchi, J. Polym. Sci., 1964, A-2, 3405. 9. M. Jinbo, K. Ochi & M. Yamada, Kobunshi Ronbunshu, 1980,

37, 57. 10. M.B. Laun ik i t i s , "Managing Corrosion Problems with P las t i c s" ,

NACE, 1977; V o l . 1 , p.190.

RECEIVED January 21, 1986

Dow

nloa

ded

by M

ON

ASH

UN

IV o

n D

ecem

ber

8, 2

014

| http

://pu

bs.a

cs.o

rg

Pub

licat

ion

Dat

e: O

ctob

er 1

4, 1

986

| doi

: 10.

1021

/bk-

1986

-032

2.ch

028


[acs symposium series] polymeric materials for corrosion control volume 322 || corrosion behavior of...

Documents