p. 1


# OAR Box 1413 Prepped by Ollie Stewart



# Document

Number: 

# 21)11-1-2 1 Docket Number: 

# A-94-5 2

Printed 7/9/2008 3:11:21 PM

Sheet 21 of 114P. 2 H\.fmm. 

# TH EEPOX Y ALTERNATIV

E

WIT H INCREASE D OSH AAN D EP A REGULATION S AN D RISIN G INSURANC E COST S AFFECTIN G STYRENATE D USERS , N O WI S TH E TIM E T O REVISI TEPOXIES
. •by Gary R. Hovan/GLS

Corporation 

# A -

... - i '••^»t-k%m
ine e thei rintroductio n i n 1948 , epox yresi n system s hav e no t bee n widel yuse d i n composite s manufacturin g outsid e o fth e aerospac e industry
. Bu t no wi s th e tim e t o revisi t epoxies
. Wit h increase d OSH Aan d EPAregulation s an d risin g insuranc e cost s affectin g styrenate d resi n users , th e cos t o fdoin g busines s i s constantl yincreasing
. I n a 198 9 rulemaking , OSH Aset th e Permis sibl e Exposur e Limi t (PEL ) fo rstyren e a t 5 0 part s pe rmillio n (ppm)
. Th e Elevent h Circui t Cour t o f Appeal s overturne d tha t rulemakin g i n 1992 , an d th e styren e PE L reverte d bac k t o 10 0 ppm . OSH A ha s establishe d a hierarch yo fcontrol s t o b e use d t o mee t th e workplac e PELs
. Limite d us e o f Nationa l Institut e o fOccupationa l Safet yan d Healt h (NIOSH ) approve d respirator s i s par t o f thi s hierarchy
. OSH Awil l b e revisitin g th e PE L issu e i n mid-1995
. Th e result s o fthi s rulemaking , whe n finalized , ma yplac e adde d restriction s o n th e us e o frespirator s fo rmeetin g workplac e PELs
. Whe n th e EPA' s Clea n Ai rAc t o f199 0 liste d styren e a s a hazardou s ai rpollutant , th e cos t o f doin g busines s bega n a n upwar d trend
. I fa busines s ha s th e potentia l o fbein g a 10-to n emitte ro fstyrene , i t wil l fal l unde rth e stringen t regulation s o fMaximu m Achievabl e Contro l Technolog y(MACT)
. Acomposite s fabricato r usin g a s littl e a s on e dru m o fresi n pe rda yma y b e force d int o thi s category . Length ypermit s a s wel l a s state-of-the-ar

t technolog yfo rreducin g emission s wil l b e necessary . Thi s coul d mea n costl ycapita l improvement s suc h a s incinerator s an d adsorptio n o rbiofiltratio n systems . Suddenl y th e cos t o fdoin g busines s increase s dramatically
. Th e resource s an d capita l requirement s t o remai n i n complianc e ar e no t insignificant
. I fon e take s int o accoun t thes e factor s an d view s th e tota l cos t o fusin g styrenate d resins , the n epox y system s shoul d b e considere d a s a feasibl e alternative
. Granted , epox yresi n system s ar e mor e expensiv e o n a pe rpoun d basi s versu s styrenate d polyeste ro rviny l este rresins
. Epox yresin s hav e benefit s tha t d o no t ad d t o th e cos t o fth e process . Mos t significantly , epoxie s d o no * contai n volatil e o rhazardou s ai rpollutants
. Thei rcontributio n t o tota l emission s i s negligibl e an d a simplifie d ai r permi t mayb e al l tha t i s required
. Fro m a worke r exposur e standpoint , mos t epox ysystem s d o no t requir e specia l o rmandate d control s othe rtha n standar d persona l protectiv e equipment
. Th e performanc e o fepox ysystem s ca n overcom e man yo fth e cost s associate d wit h usin g les s expensiv e polyeste ro rviny l este rresins
. I n marin e applications , commo n concern s ar e secondar ybondin g an d osmoti cblistering
. I f thes e issue s manifes t themselves , resolution s ar e costl yfo rmarin e fabricator s an d boa t owners . Epox yresin s ar e extremel yresistan t t o osmoti c blistering , providin g th e benefit s o flowe rwar rant yclaim s an d mor e satisfie d customers . Epox y resin s ar e als o know n fo rthei routstandin g adhesio n whic h service s t o virtuall yeliminat e secondar ybondin g problems
. A s a resul t o fthei rsuperio rfatigu e an d impac t resistance , alon g wit h excellen t fractur e toughness , epoxie s ar e th e resi n o fchoic e i n application s suc h a s automobil e lea fspring s an d wate rskis
. Thes e propertie s allo wfabricator s t o reduc e laminat e schedule s an d produc e les s costl yan d lighte rpart s withou t a los s o fperfor mance . Th e performanc e o fepoxie s complement s th e physica l propertie s o ftypica l reinforcements
. Mos t epox ysystem s ar e non-flammable , thereb yreducin g th e associate d hazard s o fusin g flammabl e styrenate d resin
. On e possibl e benefi t i s lowe rinsuranc e premium s fo rplan t facilities
. Specia l handlin g an d storag e condition s ar e require d fo rth e organi cperoxid e an d meta l sal t initiator s use d t o cur e polyeste rresins
. Thes e chemical s ar e no t use d t o cur e epox yresins
. Specia l handlin g an d storag e ar e no t require d t o kee p epox yresin s withi n specifica tion
. Th e longe rshel flif e eliminate s th e nee d t o dispos e o fmateria l tha t ma yge l prematurely
. Thi s stabilit yals o lend s itsel ft o reliabl e lot-to-lo t consistency
. Epox yresi n system s ar e availabl e a s direc t Composites FabricationlVthiuary 199 5-•> •• •"•»
. P. 3



### s.*g$&zi--• \<&\ , *"

"4 ^' ' . - I'^AEporyxaminatip g Resi n « ! 

### "'^'S. : 

### E£S ; 

### E i 

# m^mmmmm

m. Epoxide Equivalent

Wieig/i f (g/g equivalent) Viscosity (cPat

77°F ) Flas hPoi'n

f Setaflash(°F

) S/ic//Li/ e 166-17 7 •yi-M^l&s •3000-4500 ;. : i,r$^j&;Z 

## >30 0 ' y-ti$*0?-' 1 yea rminimum,.; : . '$•%' ' V Corin g Agent(CA ) •„-.•'".' • • • :*.• ' ! '.S3S V tf&^M*'"-' Amine Equivalent

Weight (g/ g equivalent

) • ' Viscosit y (c Pa t 77°F ) Flas hPoi/ifPMCC(°F ) Shelf Life 58-62 7-1 2 255 1 yea rminimu

m Cure Accelerato r Viscosity (pois e at

77°F ) 

### ShelfLtfe 40-6 0 1 yea r minimu m

- Mixe d System Properties Mix Ratio, Resin/CA part

s b y wt. , (part

s by vol. ) Resin/CA Blend

Viscosity (c Pat

77°F ) 100/35 (100/43 ) 400-60 0 Reactivit

y Accelerator

Level (part s b y wt./10 0 part s resin ) Cup Gel Time 210g . (minute s at

75°F ) 1 200 2

9 9 3 7 5 4

5 5 5

4 5

replacement s fo rpolyeste ro rviny l este rresin s use d i n spra yu p an d han d la yu p processes . Th e propertie s fo ra typica l epox yresi n laminatin g syste m ar e a s show n abov e i n th e chart
. Thi s resi n syste m offer s lo w viscosit ywithou t th e us e o f modifier s o rreactiv e diluent s thu s keepin g th e odo rverylow
. Simila rt o polyeste rresins , th e ge l tim e ca n b e varie d b ychangin g th e leve l o f th e accelerato rt o compensat e fo rseasona l change s o ftemperature . Fabricator s ca n deliberatel yadjus t th e po t lif e t o accommodat e th e need s o fth e operation
. Th e accelerato rca n b e lef t ou t fo rvacuu m baggin g wit h moderat e hea t cure s o rmor e ca n b e adde d fo rquic k

roo m tem peratur e cures . Al l thermose t resi n system s wil l benefi t fro m a pos t cur e t o develo p ultimat e physica l proper ties
. Epoxie s ar e n o differen t an d a mil d pos t cur e i s recommende d fo rconsisten t produc t perfor manc e independen t o f seasona l sho p tempera tures . Makin g provision s fo rpos t curin g ma y represen t a capita l investmen t fo rsom e facilities
. Th e cos t an d energ yo f pos t curin g ca n b e substantiall yless tha n th e cos t o fincinerator s o r 

## Epox y resi n system s ar e availabl e a s direc t replacement s fo r polyeste r o r viny l este r resin s use di n spra y u p an dhan d lay u p processes .

biofiltration
. Arelativel ycos t effectiv e metho d fo r pos t curin g i s t o us e intrinsicall ysaf e hea t lamp s tha t ca n b e lowere d directl yint o th e mold
. Mor e efficien t enclose d system s ca n effectivel ypa yfo r

themselve s wit h energ ysavings
. Faste rcur e rate s an d greate r through-pu t a s wel l a s reduce d energ yconsumptio n ca n b e realized
. Th e leadin g supplier s o f epox yresin s continu e t o develo p system s tha t fi t th e need s o f composite s fabricators
. Th e tren d towar d increasin g regulation s fo rcomposite s manu facturer s suggest s a thoroug h revie wo fal l options
. Th e benefit s o fusin g epoxie s suc h a s negligibl e emissions , superio rphysica l properties , an d hig h qualit y finishe d part s canno t b e over looked
. Whe n th e tota l cos t o f usin g styrenate d resin s i s exam ined , epox yresi n system s becom e a n increasingl yattractiv e alternative
. A Special thanks to Gary A. Hunter, Senior

Technical Associate, Shell

Development

Company, Houston, TX, and

Nancy Dehmlow, Vicefresidenl of Health, Safety, and

Environment, GLS

Corporation for their input.
1 0 Composites Fabrication/February 199 5