Fiberglass is a composite material made of glass fibers set in a plastic resin matrix. Glass fibers have high tensile strength but are weak in shear. Common resins used are polyester, epoxy, and vinyl ester. Fiberglass is produced by drawing glass into fine fibers, coating them, and combining the fibers with resin. It is used in many applications due to its high strength to weight ratio and resistance to corrosion.
2. Source: http://chemsrv1.uwsp.edu/fire/FireCD/macrog/mpm/composit/fiber/fibeglas/history.htm
History
Ancient Egyptians and Phoenicians 1880 – Hermann
are among the many civilizations Hammesfahr was awarded
who produced small amounts of a patent for a fiberglass
coarse glass fibers for decoration cloth interwoven with silk
1870 - John Player developed a
method for mass-producing glass
fibers with a steam jet process. It
was used for insulation.
3. Source: http://chemsrv1.uwsp.edu/fire/FireCD/macrog/mpm/composit/fiber/fibeglas/history.htm
History
Carlton Ellis of Du
Pont was awarded a 1942 – Owens-Corning were
patent for polyester already producing fiberglas and
resin. polyester airplane parts
Present
Dale Kleist, working for Corning
1937 – Ray Greene, working with
Glass, accidentally discovered an easy
Owens-Corning produced a
method to create fiberglass: when a jet
sailboat w/ polyester
of compressed air hit molten glass. In
resin/fiberglass composite
1936, the companies Corning Glass and
Owens-Illinois patented the product
“Fiberglas”
9. Source: http://www.umaine.edu/adhesion/gardner/5502002/glass%20fibers.pdf
Glass Fiber
• Properties
– Mechanical Properties
• similar to glass but different strength value
– Chemical Stability
• Susceptible to alkaline solutions and hot water
– Thermal Properties
• High heat resistance
– Electrical Properties
• insulator
Return to Contents Next: Processing
11. Source: http://www.madehow.com/Volume-2/Fiberglass.html#b
Glass Fiber Processing
Raw Materials
• Major • Others
– Silica – Glass former – Calcined Alumina
– Limestone – Borax
– Soda Ash – Lowers mt. – Feldspar
pt. w/ limestone – Magnesite
– Waste glass – a.k.a. – Etc.
cullet
Return to Contents Next: Batching
12. Source: http://www.compositesworld.com/articles/the-making-of-glass-fiber
Glass Fiber Processing
Batching
• Batching - exact quantities of raw materials
are mixed together before being melted.
• Materials are added to lower the working
temperature and add additional properties.
• Some properties of other components:
– Al2O3, CaO, MgO – alkali-resistant
– B2O3 – increase Tmelting - Tcrystalline
13. Source: http://www.compositesworld.com/articles/the-making-of-glass-fiber
Glass Fiber Processing
Batching
• E-glass (Electrical resistance)
– Contains Al2O3, CaO, MgO, and B2O3
• S-glass (Strength)
– Contains Al2O3, MgO, and B2O3 and significantly
more SiO2
• C-glass (Chemical resistant)
– Large content of B2O3
• A-glass (Alkali resistant)
– No content of B2O3
Return to Contents Next: Melting
14. Source: http://www.compositesworld.com/articles/the-making-of-glass-fiber
Glass Fiber Processing
Melting
• Common furnaces has three sections:
– “Receiver”
• The batch is melted and uniformly. Bubbles are also
removed
• High temperature ( 1400oC or 2552oF)
– Refiner
• High temperature ( 1370oC or 2500oF)
– Forehearth – beneath this is are bushings
15. Source: http://www.compositesworld.com/articles/the-making-of-glass-fiber
Glass Fiber Processing
Melting
• Three approaches to melting
– Indirect melt – a.k.a. marble remelt
• Molten glass is sheared and rolled into marbles w/
diameter of 0.62 inch (15-16 mm), then cooled and
packaged to a fiberization process.
• Useful for outsourcing
– Large-scale direct melt
• 8000-100000 tons per year
– Small-scale direct melt – a.k.a. paramelters
• 150 to 200 metric tons per year
Return to Contents Next: Fiberization
16. Source: http://www.compositesworld.com/articles/the-making-of-glass-fiber
Glass Fiber Processing
Fiberization
• Extrusion • Attenuation
– Extruded through 200- – Drawing extruded
8000 bushings made of molten glass into
Pt-Rh alloy filaments using high-
– Bushings are heated speed winder (tangential
electronically to speed of ~2miles/~3km
maintain T per minute)
( 1204oC/2200oF) and – High-speed winding
consequently, glass applies tension
viscosity and thickness – Diameter 4 m to 34 m
*Varying cooling process change the form of the fiber
20. Source: http://www.umaine.edu/adhesion/gardner/5502002/glass%20fibers.pdf
Glass Fiber Processing
Drying
• Collection of sized filaments
– Strands
• produce twine-like strands
– Winders
• produce balls or “doffs”
• Used in attenuation
– Creel
• produce multi-end products
Back to Glass Fiber
Processing Next: Packaging
21. Source: http://www.madehow.com/Volume-2/Fiberglass.html#b
Glass Fiber Processing
Packaging
• Continuous-filament
– Rolled in drums and formed into yarns
• Staple-fiber
– while cooling, jets of air break filaments into
lengths of 8-15 inches
22. Source: http://www.madehow.com/Volume-2/Fiberglass.html#b
Glass Fiber Processing
Packaging
• Chopped fiber
– Yarns are chopped into short, uniform lengths
• Glass wool
– Cooling involves a downward jet of (hot)
air, making the fibers fall randomly onto a
conveyor belt, forming a fleecy mass
Back to Glass Fiber
Processing Next: Resins
27. Source: http://scholar.lib.vt.edu/theses/available/etd-42198-113329/unrestricted/ch1.pdf
Resin Properties
• Vinyl
– Combined properties of Unsaturated Polyester
and Epoxy
– Easy to handle at room T
– Better chemical resistance
– Greater corrosion resistance
– Greater cure rate control
– Cheaper than epoxy, but more costly than
polyesters
Return to Contents Next: Processing
28. Resin Processing
• Essentially polymerization in a large scale
Raw Materials
Processing
Polymerization
Return to Contents Purification Next: Raw Materials
29. Resin Processing
Raw Materials
Polyester Epoxy
• Glycols • Alkaline catalyst(amine or
– Propylene glycol – low NaOH)
cost, balanced properties • Bisphenol A
– Bisphenol A/PG – good
chemical resistance, high heat • Epichlorohydrin
deflection T • Solvent
• Acids/anhydrides • Water
– Unsaturated acids/anhydrides
– Saturated acids/anhydrides
Source: Source:
http://www.umaine.edu/adhesion/gardner/5502002/poly http://processflowsheets.blogspot.com/2011/05/epoxy-resin-
ester%20resins.pdf manufacturing-process.html
30. Source: http://scholar.lib.vt.edu/theses/available/etd-42198-113329/unrestricted/ch1.pdf
Resin Processing
Raw Materials
• Vinyl esters
– There are various ways to produce vinyl
esters, usually of resins and unsaturated acids
• Addition products of epoxide resin and ethylenically
unsaturated monocarboxylic acids
• Glycidyl methacrylate + multifunctional phenol (e.g.
Bisphenol-A)
Return to Contents Next: Polymerization
33. Resin Processing
Purification
• Evaporators and phase separators in the
processes separate the final resin from
unreacted reactants and unwanted brine.
Return to Contents Next: Application
34. Resins
Application to Glass Fibers
Source: http://centralfloridafieros.com/forum/index.php?topic=149.0;wap2
Polyester Epoxy
• Hardening catalyst (methyl • Varying hardening catalyst
ethyl ketone peroxide, or type and ratio, depending
MEKP) with a very low ratio on type of epoxy (common
(few drops per ounce of ratios are 1:1, 3:1, 4:1)
resin)
• Mixed with some wax - wax
rises as resin cures
• Open surface must be facing
up
• Wax is removed afterwards
• Exothermic
Source: http://centralfloridafieros.com/forum/index.php?topic=149.0;wap2
35. Resins
Application to Glass Fibers
• Vinyl Esters
– Ideally catalyzed by triphenylphosphine, but can
cure by itself
– Requires diluents (e.g. styrene)
• Usually composed of 40-50 wt. % styrene
Return to Contents Next: Fiberglass
45. Source http://centralfloridafieros.com/forum/index.php?topic=149.0;wap2
Fiberglass Processing
Molding
• Plug
– Object with desired shape
– Can be formed with foams, wood, plaster, etc.
• Mold
– Supports glass fibers during resin curing
• Mold release agent
– E.g. Polyvinyl alcohol
• Gelcoat
– Pigmented resin, harder, more durable finish
– Followed by a coating of a fiberglass
46. Source: http://www.clubkitclearcote.com/instructions/Hand%20Layup.pdf
Fiberglass Processing
Molding
• Lay-up
– Hand lay-up
• Hand pressure/vacuum/rollers used to ensure even
resin application
– Spray lay-up
• Resin and reinforcements are sprayed onto the vertical
mold
– Vacuum bag
• Fiber and resin are sucked to conform to the mold using
a vacuum
Some common Resins and Unsaturated Acids:ResinsDiglycidyl Ether of Bisphenol AEpoxy NovolacCycloaliphatic EpoxyUnsaturated acidsAcrylic acidMethacrylic acidCrotonic acidCinnamic acid