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EPOXY
Presented By-Biswajit Maity
M.Sc. in Polymer Science
CIPET-AHMEDABAD(INDIA)
Contents…..• History
• Introduction
• Structure
• Chemistry
• Curing/hardener
• What makes epoxy resins special
• Properties
• advantages
• Application
• Health risks
• Marketability
• Industries
• Conclusions
• Reference
Epoxy Resins
• Found by C. Castan in 1930s on his search for dental use and successfully introduced by Ciba by end 1940s in the electro industry as insulating material, as coating and laminating material, as well as adhesive.
Epoxy Resin• Also called "epoxy" or "polyepoxide".
• Second most widely used family of thermosets copolymer(after polyesters)
• Large portion of uses are non-reinforced (adhesives, paints, etc.)
• Circuit boards are the largest reinforced application (low conductivity, low volatiles)
• General Properties:• High Mechanical Properties: large cohesive force• Good Adhesive Performance: great number of polar group• Excellent stability: without impurities(base and salt)• Flexibility and diversity in DesigningBecause of the stability and mechanical properties, epoxy resin coating owns great chemical and physical resistance.
Epoxy Structure
C C
Epoxy ring
OC C
O
()n
Polymer portion
Epoxy ring
Number of repeat units
EPOXY CHEMISTRY
Improved Epoxy Resins :Epoxy Cresol Novolac (ECN)
• In the mid sixties, new multi functional epoxy resins of phenol novolac or cresol novolac were introduced in the market.
• The chemistry of these resins is very similar to that of Bisphenol-A type resins.
• The main purpose of using these resins was to improve the cross linking density of the formulation
Novolac epoxy resin
• Reaction of phenols with formaldehyde and subsequent glycidylation with epichlorohydrin produces epoxidised novolacs, such as epoxy phenol novolacs (EPN) and epoxy cresol novolacs (ECN).
• These are highly viscous to solid resins with typical mean epoxide functionality of around 2 to 6.
• The high epoxide functionality of these resins forms a highly crosslinked polymer network displaying high temperature and chemical resistance, but low flexibility.
• 100% solids hybrid novolac epoxy resin systems have been developed that contain no solvents and no volatile or organic compounds. These hybrid novolac epoxies have been documented to withstand up to 98%sulfuric acid
Bisphenol A epoxy resin• The most common and important class of epoxy resins is formed from reacting
epichlorohydrin with bisphenol A to form diglycidyl ethers of bisphenol A.
• reacting two moles of epichlorohydrin with one mole of bisphenol A to form the bisphenol A diglycidyl ether (commonly abbreviated to DGEBA or BADGE).
• DGEBA resins are transparent colourless-to-pale-yellow liquids at room temperature,with viscosity typically in the range of 5-15 Pa.s at 25 °C.
• since pure DGEBA shows a strong tendency to form a crystalline solid upon storage at ambient temperature.
• which are semi-solid to hard crystalline materials at room temperature depending on the molecular weight achieved. As the molecular weight of the resin increases,
• the epoxide content reduces and the material behaves more and more like a thermoplastic. Very high molecular weight polycondensates (ca. 30 000 – 70 000 g/mol) form a class known as phenoxy resins
Bisphenol F epoxy resin
• Bisphenol F may also undergo epoxidation in a similar fashion to bisphenol A.
• Compared to DGEBA, bisphenol F epoxy resins have lower viscosity and a higher mean epoxy content per gram, which (once cured) gives them increased chemical resistance.
Aliphatic epoxy resin• There are two types of aliphatic epoxy resins: glycidyl epoxy resins and
cycloaliphatic epoxides.Glycidyl epoxy resins are typically formed by the reaction of epichlorohydrin with aliphatic alcohols or polyols to give glycidyl ethers or aliphatic carboxylic acids to give glycidyl esters.
• This reaction is normally done in the presence of an alkali, such as sodium hydroxide, to facilitate the dehydrochlorination of the intermediatechlorohydrin. The resulting resins may be monofunctional (e.g. dodecanol glycidyl ether), difunctional (diglycidyl ester of hexahydrophthalic acid), or higher functionality (e.g. trimethylolpropane triglycidyl ether).
• These resins typically display low viscosity at room temperature (10-200 mPa.s) and are often used as reactive diluents. As such, they are employed to modify (reduce) the viscosity of other epoxy resins. This has led to the term ‘modified epoxy resin’ to denote those containing viscosity-lowering reactive diluents. However, they are also used without other epoxide ingredients along with anhydride curing agents such as hexahydrophthalic anhydride to make molded objects such as high voltage insulators. This is in fact the main use of the diglycidyl esters.
• The cycloaliphatic epoxides contain one or more cycloaliphatic rings in the molecule to which the oxirane ring is fused (e.g. 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexane carboxylate). They are formed by the reaction of cyclo-olefins with a peracid, such as peracetic acid.[4] This class also displays low viscosity at room temperature, but offers significantly higher temperature resistance and correspondingly better electrical properties at high temperatures to cured resins than the glycidyl aliphatic epoxy resins.
• Another advantage is the complete absence of chlorine, since no epichlorohydrin is used in the manufacturing process. This is particularly useful for electronic applications such as the encapsulation of light emitting diodes. However, room temperature
• reactivity is rather low compared to other classes of epoxy resin, and high temperature curing using suitable accelerators is normally required.
Glycidylamine epoxy resin
• Glycidylamine epoxy resins are higher functionality epoxies which are formed when aromatic amines are reacted with epichlorohydrin.
• Important industrial grades are triglycidyl-p-aminophenol (functionality 3) and N,N,N,N-tetraglycidyl-4,4-methylenebis benzylamine (functionality 4).
• The resins are low to medium viscosity at room temperature,
• which makes them easier to process than EPN or ECN resins.
• This coupled with high reactivity, plus high temperature resistance and mechanical properties of the resulting cured network make them
• important materials for aerospace composite applications.
Epoxy − specific molecules
CCCO
CCCO
NC C C
O
C C CO
N C
C
C
C
CO
C
C
C
C
CO
C
C
C
CO
C
a) Diglycidyl Ether of Bisphenol A (DGEBPA)
b) Tetraglycidylmethylenedianiline(TGMDA)
c) Epoxidized phenolic resin(Epoxy Novalac)
CO CO
C
C
C
OCCCO
OH
COCCCO c
c n
( )n
Properties with chain length (n)
Number of repeat units (n)
Heat Distortion Temperature (HDT) (°F/°C)
Physical state
2 105/40 Semi-solid
4 160/70 Solid
9 265/130 Solid
12 300/150 Solid
Epoxy − specialty molecules
OO
CCOCCOCCCOH
C O C C COH
O C C O C C COH
NCCCNH2
C C COH
O C C O C C CO
Toughened Epoxy Resin
O
CC
ON
C
O
OCCCOC
C C CO
OC
O
CC
ON
C
O
OC C C O C
CCCO
O CC
High Temperature Epoxy Resins
Epoxies − HDT and structureResin Type(predominate)
Heat Distortion Temp (HDT) (°F/°C)
Aliphatic (straight chain)
255-270/125-132
Aliphatic (cyclical)
230-300/110-150
Aromatic(cyclical)
290-350/145-175
Aromatic (straight chain)
265-290/130-145
Curing Epoxies
• Epoxies use hardeners instead of initiators for curing
• Hardeners can be almost any molecule that will react with (open) the epoxy ring
Epoxy Crosslink Mechanism
HHN
C
C...
C
O
C C...
N
C
C...
C C C...
O
C C
H H
Hardener
Epoxy
The other end can also react.
Cured Polymer
Curing
C C
Epoxy ring
OC
O
()n
Epoxy ring
N
N
HH
HH
N
N
HH
HH
C
Hardener molecules have tworeactive ends, so they can eachreact with two epoxy molecules.
Effects of various hardenersHardeners Advantages Disadvantages
Aliphatic amines Convenience, low cost, room temp cure, low viscosity
Skin irritant, critical mix ratios, blushes
Aromatic amines Moderate heat resistance, chemical resistance
Solids at room temp, long and elevated cures
Polyamides Room temp cure, flexibility, toughness, low toxicity
High cost, high viscosity, low HDT
Amidoamines Toughness Poor HDT
Dicyandiamide Good HDT, good electrical Long, elevated cures
Anhydrides Heat and chem resistance Long, elevated cures
Polysulfide Moisture insensitive, quick set Odor, poor HDT
Catalytic Long pot life, high HDT Long, elevated cures, poor moisture
Melamine/form. Hardness, flexibility Elevated temp cure
Urea/form. Adhesion, stability, color Elevated temp cure
Phenol/form. HDT, chem resistance, hardness
Solid, weatherability
Epoxy and Polyester ComparisonComparisons Polyester Epoxy
Active site C=C
Crosslinking reaction Addition/free radical Ring opening
Crosslinking agent Initiator (peroxide) Hardener
Amount of x-link agent 1-2% of resin 1:1 with resin
Solvent/viscosity Styrene (active)/low Infrequent/high
Volatiles High Low
Inhibitors, accelerators
Frequent Infrequent
Reactant toxicity Low Moderate
Cure conditions Room temp or heated Heated (some room)
Shrinkage High Low
Post cure Rare Common
OC C
Polyester and Epoxy − PropertiesProperty Polyester Epoxy
Adhesion Good Excellent
Shear strength Good Excellent
Fatigue resistance Moderate Excellent
Strength/stiffness Good Excellent
Creep resistance Moderate Moderate to good
Toughness Poor Poor to good
Thermal stability Moderate Good
Electrical resistance Moderate Excellent
Water absorption resist Poor to moderate Moderate
Solvent resistance Poor to moderate Good
UV resistance Poor to moderate Poor to moderate
Flammability resistance Poor to moderate Poor to moderate
Smoke Moderately dense Moderately dense
Cost Low Moderate
What makes epoxy resins special
• The aromatic structure of the resin implements a strong hydrophobic performance far over competitive resins like polyurethanes or acrylics, which were developed at the same time.
Corrosion resistance
Epoxy based formulations give corrosion resisting coatings or laminates .
• Absolutely non porous
• Tough and resistant to impact
• Flexible enough to withstand expansion without damage due to temperature changes
• Excellent adhesions on various substrates
• Film thickness is adaptable
• Highly resistant to chemicals, solvents, moisture andelevated temperatures
• Film-forming time is as short as possible
• Long pot life of room temperature curable systems
• Easy to apply
Other advantages of epoxy systems• Excellent adhesion
• Low shrinkage on cure typically > 3%
• Excellent water, heat and chemical resistance
• Versatile (formulations can be tailor made to theneeds)
• No release of volatiles during curing (addition reaction)
Corrosion resistance improvement
• The performance of epoxy resins can be
improved by selecting the proper
hardeners, pigments, fillers and suitable
additives
Environmentally Friendly Epoxy Formulations• Epoxy based coatings are reformulated into ecologically
acceptable and energy saving systems without loosing their excellent corrosion resistant performance.
• Instead of organic solvents, water was used, which was cheap, nonflammable and non-toxic. Such epoxy coating systems, dissolved or dispersed in water have for a long time captured a substantial share of the market as electro-deposition primer for car bodies
Corrosion protection of crude oil tanks• The compete absence of volatile components in combination with
liquid epoxy resins, reactive diluents and low viscose hardeners makes it possible to formulate coatings – or reinforced with glass fibres as laminates – with high corrosion resistance performance to protect the inside of storage tanks for crude oil and other chemicals.
• Several tank farms in the Middle East have been successfully coated many years ago and are still functional.
Corrosion protection of ship ballast tanks• This highly corrosive environment requires a rugged epoxy coating,
designed for immersion service in salt water ballast tanks and fuel/sea water ballast tanks.
Engineering
• Protective coatings are therefore usually based on primers containing a linseed oil or alkyd binder and anti-corrosion pigments such as red lead, lead chromate, zinc chromate, potassium zinc chromate, and zinc dust.
• The completed coating system will have a dry thickness of 5 to 10 mils.
Corrosion protection in Civil Engineering• Quartz sand filled systems enable the application as mortar or self-
levelling flooring.
• These cold curing systems are applicable even under unfavorable conditions, such as at temperatures close to the freezing point, high humidity and even under water.
Corrosion protection in Civil Engineering(Powder Coating)• Reinforced steel bars embedded into concrete can corrode because
of chloride attack, carbonation effect and humidity in a marine and coastal environment. This takes place if the alkaline environment surrounding the bars slowly changes with reduction of pH-value from 12.7 to under 8.4.
• The rust products of corroding steel bars occupy much more volume than that of original steel and the expansion pushes out the concrete cover and causes cracks.
Corrosion protection in CivilEngineering (Powder Coating• The protection of such rebar with suitable epoxy powder coating prevents such corrosion
Corrosion protection in CivilEngineering
Powder Coatings
• The electrostatic application of a fine pulverized, completely solvent free, solid epoxy resin/hardener system in the early seventies was
• a real break through in the coating industry!
• The higher molecular weight resins (1200 – 1800), based on Bisphenol-A were predestined to be suitable for their outstanding performance in having a low melting point and viscosity and various functionalities.
• High purity and practically no gelled particles which would deteriorate the final quality of the coating.
Powder Coatings
• Quality metal substrates like furniture and kitchenappliances, gardening equipment, sport goods as well as parts under the hoods of the car body are powder coated.
• The automotive industry additionally offers significant increase potential regarding on-line surface primer as a second layer on top of the electro-deposition primer with excellent corrosion and stone chip resistance.
• Due to their excellent anti corrosion properties, high reactive powder systems are mainly used to protect steel pipes transporting water, oil or gas.
Powder Coatings
• In general the performance of the powder coatings is influenced by several factors depending on the epoxy resin types:
• Average molecular weight
• Molecular distribution
• End-group functionality VS epoxy content
• Degree of chain branching
• Compatibility with the co-reactant
• Easy homogenization in the extruder.
As for Epoxy Resin Coatings...
• Epoxy coatings were developed for heavy duty service on metal substrates and use less energy than heat-cured powder coatings.
• Their low volatility and water clean up makes them useful for factory cast iron, cast steel, cast aluminum applications and reduces exposure and flammability issues associated with solvent-borne coatings.
Industrial Flooring
Waterproofing
Industrial Applications• Waterproofing – roofing, sealing, bonding
• Concrete repairs – weather, lightweight yet strong
• Metal protection – corrosion resistant
Before
After repair
Industrial ApplicationsIndustrial flooring
•rubber carpet: playgrounds, water parks, bathrooms chemical resistant and hard-wearing
•non-slip flooring: stadiums, gyms, industry
Health risks
Primary risk associated with epoxy use is often related to the hardener component
• Amine hardeners –corrosive, toxic and/or carcinogenic or mutagenic.
• Aromatic amines -health hazard (most are known or suspected carcinogens) their use is now restricted to specific industrial applications.
• safer aliphatic or cycloaliphatic amines are commonly employed.
• Liquid epoxy resins in their uncured state-irritant to the eyes and skin, as well as toxic to aquatic organisms.
• Solid epoxy resins are generally safer than liquid epoxy resins.
• Exposure to epoxy resins can, over time, induce an allergic reaction.
“Marketability” of the Epoxy Coatings Industry• Epoxy coatings are chemically resistant to water, saltwater, organics,
and acid
• Also resistant to mechanical damage (scratches)
• Also does not deform at high temperatures, due to its thermoset polymer nature
• Thanks to this wide variety of desirable properties and applications, epoxy coating are marketed in industrials, commercial, and residential sectors
Demand and Applications for Epoxy
The Industry of Epoxy Resins•China produces 30% or the worldwide market.
•$5 Billion industry in North America• Hexion (Shell Development Company)• Dow Chemical Company• Huntsman Corporation’s Advanced Materials
•Some current applications are on “under-the-hood” automotive components, floor coatings, underground tanks/pipes/cables, electrical connectors, circuit boards, adhesives, structural support additive in high stress areas like wind turbines and aerospace frames
Marketability
Marketability
SHANKAR DYES & CHEMICALS
Contact Person Mr. Dalip Kumar (CEO)
Address
No. 1209, Shankar Building,Gali No.11, Sadar BazarNew Delhi, Delhi - 110 006, India
Mobile+(91)-9810355592 / 9910007842/9910007832
Phone+(91)-(11)-23673462 / 23616830 / 23558239 / 23618457
E-mail [email protected]
Supreme Silicones
Contact Person : Omkar Waikar
A − 704, Nancy Lake Homs, Satara Road,Opp. Bharati Vidyapeeth, Katraj,Pune, Maharashtra 411046India.
Tele : +91 20 2410 8067Mobile : +91 9822281671Email : [email protected] : [email protected]
HuangShan KBR Chemical CO.,LTD Manufacturer[China (Mainland)]
• Street Address :No 316 QingHeLiTing, AnDong Road, TunXi district, HuangShan city, AnHui P.R.,CN
• City :huangshan
• Country/Region :China (Mainland)
• Telephone:86-559-2335676
• Office Address: 30/F, Yanqiao Building , No.89 Yanling Road , Tian He District , China
• Tel:0086-20-62213889 Fax: 0086-20-62213898
• Email: [email protected] , [email protected] , [email protected]
•
• MSN: [email protected] , [email protected] , [email protected]
• SHREEJI PHARMA INTERNATIONAL
•
India Office
• Mr. Nilesh Sheth / Mr. Tushar Kavade
• 311, ATLANTIS HEIGHTS,SARABHAI MAIN ROAD,VADIWADI, Vadodara - 390 007Gujarat, INDIA.Tele:0091-265-2313036
•
Mobile:8866002331 / 8758805202
•
Email:[email protected],[email protected]
•
Skype Id :Nilesh.sheth70
Contact Person:
Mr. Vinod Sapla
Address :
A-701, Parasnath Darshan Complex, Kirol - Kurla Road, Vidyavihar, Ghatkopar (west).
City :
Mumbai
State :
Maharashtra
Country :
India
Pin Code :
400086
Phone :
+91-22-22918490
Fax :
+91-22-25128442
Email Address :
Mobile :
+91-9321003115
Web Site :
http://www.am-global.com
Global Polytech Shanti Niketan, Opposite Mahindra Global Gallery, Ghodbandar Road, Ovala Naka, Ovala, Thane - 400615, Maharashtra, Indiawww.indiamart.com/globalpolytech ,Contact no-08377809504
Stanvac-superon Group Plot No. 552, Sector 37, Pace City II , Gurgaon - 122001, Haryana, Indiawww.stainlesssteelwiresindia.comContact no-08377801164
D & R Tech Mart Pvt. Ltd. GF - 8, Guru Nanak Market, Opposite D.A.V. School, Sector- 17 , Gurgaon - 122001, Haryana, Indiawww.indiamart.com/drtechmartContact no- 09953359946
Clean Coats Pvt. Ltd. No. 101, Metro House, B- Block, Metro Estate, No. 178 CST Road, Behind Mercedes Benz Showroom, Mumbai - 400098, Maharashtra, Indiawww.indiamart.com/cleancoatsContact no-08377801668
MPR Technique No. 6, Thirumalai Nagar 200 Feet Road, Kolathur, Chennai - 600099, Tamil Nadu, Indiawww.epoxyfloor.co.inContact no-08447564070
Roto Polymers And Chemicals 63, Reddipalayam Road, Mugappair West , Chennai - 600037, Tamil Nadu, Indiawww.rotexepoxy.comContact no-08373904240
Conpro Chemicals Private Limited E- 8, Site- 4, Industrial Area , Sahibabad - 201010, Uttar Pradesh, Indiawww.conprochemicals.comContact no-08376808245
S. M. Adhesives Shop No. 4, Ganga Bhuvan, SRPS Road, Opposite Chetna Apartment, Bhandup West , Mumbai - 400001, Maharashtra, Indiawww.smadhesives.netContact no-08447509908
Marble Magik Corporation C/5 /4, Road No. 8, Hojiwala Industrial Estate, SSUML, Sachin, Surat - 394230, Gujarat, Indiawww.magikgroup.inContact no-09953353143
Shankar Dyes & Chemicals No. 1209, Shankar Building, Gali No. 11, Sadar Bazar , New Delhi - 110 006, Delhi, Indiawww.shankardyes.comContact no-08447498163
Grauer & Weil (I) Ltd Akurli Road, Kandivli East , Mumbai - 400101, Maharashtra, Indiawww.grauerandweil.comContact no-08586970105
Perma Construction Aids Private Limited No. 611/612, Nirmal Corporate Center, Mulund West , Mumbai - 400080, Maharashtra, Indiawww.permaindia.inContact no-08373904199
Conclusion•Epoxy Resin Coatings' Performance:
•Properties-Adhesion,Shear strength,Fatigue resistance,Strength/stiffness,Creep resistance, Thermal stability,Electrical resistance, Solvent resistance
•Producing☺☺•Cost-Moderate
As a result, epoxy resin coatings has been widely used in many different conditions.
Reference:
• http://en.wikipedia.org/wiki/Epoxy_resin
• http://en.wikipedia.org/wiki/Coating
• http://www.epoxy.com/633.aspx
• http://www.hitechcivilindia.com/pronserv.htm
• http://www.sika.in/construct_project.htm
• http://jycl.tede.cn/2008/05/120995758970581.html
• http://www.knovel.com/web/portal/knovel_content