fiberglass reinforced plastic

Glass fiber reinforced plastic , short GRP ( English GFRP - glass-fiber reinforced plastic ), a Fiber-reinforced plastic from a plastic and glass fibers . Both thermosetting plastics (e.g. polyester resin [UP] or epoxy resin ) and thermoplastics (e.g. polyamide ) can be used as the basis.

Continuous glass fibers were first produced industrially in the USA in 1935 as reinforcement fibers. Mass production was developed in the 1930s by Games Slayter (Owens Corning) and others - at that time the material was mainly used to insulate houses. The first aircraft made of GRP was the Fs 24 Phönix from Akaflieg Stuttgart from 1957.

GRP is also known colloquially as fiberglass . The word fiberglass is an Anglicism that was formed from fiberglass ( AE ) or fiberglass ( BE ), the English word for glass fiber. In the non-specialist world, they often only speak of fibers when they talk about GRP or carbon fiber reinforced plastic (CFRP). However, the fiber-reinforced plastics are always meant, because without the plastic matrix that gives shape and surface, the components would not be able to be manufactured.

Properties and areas of application

properties
Fiber type: E- glass fiber Matrix type: epoxy resin Fiber volume fraction 60% All data are characteristic average values
Basic elasticity quantities
${\displaystyle E_{\|}}$	44,500 N / mm²
${\displaystyle E_{\perp }}$	13,000 N / mm²
${\displaystyle G_{\perp \|}}$	5,600 N / mm²
${\displaystyle G_{\perp \perp }}$	5 100 N / mm²
${\displaystyle \nu _{\|\perp }}$	0.25
density
${\displaystyle \rho }$	2.0 g / cm³
Basic strength
${\displaystyle R_{\|}^{+}}$	1,000 N / mm²
${\displaystyle R_{\|}^{-}}$	900 N / mm²
${\displaystyle R_{\perp }^{+}}$	50 N / mm²
${\displaystyle R_{\perp }^{-}}$	120 N / mm²
${\displaystyle R_{\perp \|}}$	70 N / mm²
Coefficient of thermal expansion
${\displaystyle \alpha _{\|}}$	7 · 10 −6 1 / K
${\displaystyle \alpha _{\perp }}$	27 · 10 −6 1 / K

GRP break in the SEM in stereoscopic representation, magnification 50 × (based on medium format negative )

GRP fracture in the SEM in stereoscopic representation, magnification 200 × (based on medium format negative)

GRP break in the SEM in stereoscopic representation, magnification 500 × (based on medium format negative)

GRP break in the SEM in stereoscopic representation, magnification 1000 × (based on medium format negative)

Glass fiber reinforced plastics are an inexpensive, yet very high-quality fiber-plastic composite . In mechanically highly stressed applications, glass fiber reinforced plastic is found exclusively as continuous fibers in fabrics or in UD tapes.

Compared with fiber-plastic composites made from other reinforcing fibers, the glass-fiber reinforced plastic combined with a suitable plastic matrix has high elongation at break, high elastic energy absorption, but a relatively low modulus of elasticity . Even in the direction of the fibers, it is below that of aluminum. It is therefore not suitable for components with high rigidity requirements, but is good for leaf springs and similar components.

Glass fiber reinforced plastic has excellent corrosion behavior even in an aggressive environment. This makes it a suitable material for tanks in plant construction or for boat hulls. Since these hulls are also non-magnetic , the material was used to build minesweepers as early as 1966 .

The higher than that of carbon fiber reinforced plastic lying density is taken in these applications into account.

With a suitable matrix, glass fiber reinforced plastic has a good electrical insulation effect, which makes it a very useful material in electrical engineering. Especially insulators that have to transmit high mechanical loads are made of glass fiber reinforced plastic. Switch cabinets for outdoor use are often made of GRP due to the durability and stability of the material.

Market situation

In 2015, around 1,069,000 tons of GRP were produced in Europe. The most important customer was the transport industry with 35% of the total, followed by the construction industry (including for rotor blades for wind turbines) and the electronics and sports equipment industry with 30%.

In 2014, the following quantities of glass fiber reinforced plastic were processed in Europe:

• Containers and pipes, mainly in the filament winding and centrifugal process: 145e⁶ kg
• GMT and LFT (see fiber matrix semi-finished products ): 121e⁶ kg
• Continuous processes such as B. Pultrusion : 132e⁶ kg
• RTM procedure: 132e⁶ kg
• Pressing SMC and BMC : 264e⁶ kg
• Open form processes such as B. Hand lamination or fiber spraying: 232e⁶ kg
• other procedures: 17e⁶ kg

A total of 1,043 kt of glass fiber reinforced plastic was processed in Europe in 2014.

sorts

Some typical types of glass fiber reinforced plastics are:

	EN 60893-3	NEMA LI 1-1998	Mil
Epoxy resin laminate	EP GC 202	FR-4	MIL-I-24768/27 (GEE-F)
Epoxy resin laminate	EP GC 204	FR-5	MIL-I-24768/28 (GEB-F)
Epoxy resin laminate	EP GC 201	G-10	MIL-I-24768/2 (GEE)
Epoxy resin laminate	EP GC 203	G-11	MIL-I-24768/3 (GEB)
Melamine resin laminate	MF GC 201	G-5	MIL-I-24768/8 (GMG)
Melamine resin laminate	MF GC 201	G-9	MIL-I-24768/1 (GME)
Phenol-formaldehyde resin - laminate	PF GC 301	G-3	MIL-I-24768/18 (GPG)
Polyester resin laminate	UP GM 201	GPO-1	MIL-I-24768/4 (GPO-N-1)
Polyester resin laminate	UP GM 202	GPO-2	MIL-I-24768/5 (GPO-N-2)
Polyester resin laminate	UP GM 203	GPO-3	MIL-I-24768/6 (GPO-N-3)
Polyester resin laminate		GPO-1P	MIL-I-24768/31 (GPO-N-1P)
Polyester resin laminate		GPO-2P	MIL-I-24768/32 (GPO-N-2P)
Polyester resin laminate		GPO-3P	MIL-I-24768/33 (GPO-N-3P)
PTFE laminate			MIL-I-24768/7 (GTE)
Silicone resin laminate	SI GC 201	G-7	MIL-I-24768/17 (GSG)

Typical components

Short and long fiber reinforced components

Short fiber reinforced components are mainly used as cladding or are manufactured because of their good malleability and great design freedom. Components reinforced with short fibers usually have a quasi-isotropic behavior because the short fibers are randomly distributed. A weakly pronounced orthotropy can arise during the injection molding of short-fiber reinforced thermoplastics. The fibers are oriented along the flow lines. The addition of short glass fibers to thermoplastics improves their stiffness, strength and especially their behavior at high temperatures. The creep of short fiber reinforced thermoplastics is less than that of the base material.

Continuous fiber reinforced components

Continuous fiber reinforced components are manufactured with defined material properties. They are used more and more frequently in lightweight construction .

• GRP made from fabrics or scrims
• GRP made from rovings or unidirectional fabrics / scrims (manufactured using the strand drawing process )
• Mixed forms from the types mentioned above

Duroplastics are usually used as the matrix . For example, a composite material made of woven glass fiber mats and polyester resin has become known under the term fiberglass .

Applications (selection)

• Reinforcement in concrete construction
• Leaf springs
• Shower trays and bathtubs
• Vehicle parts (e.g. hoods, fenders)
• Sleeves and envelopes
• Small molded parts
• Climbing aids for greening facades with climbing plants
• Profiles and reinforcements
• Tube
• Rotor blades for wind turbines and helicopters
• Hulls and wings of sailplanes or high-performance powered aircraft
• Hulls of boats and yachts
• Vehicle fairings in automobile racing
• Playground slides / slides
• Batons and violin bows
• Cladding and facades
• Limbs for crossbows
• Fishing components
• Bracket for overhead tram lines
• Hangar and industrial doors
• Printed circuit boards
• Cooling towers
• Protective cover for UHF transmitting antennas
• Tanks for the food and chemical industry

Manufacturing and processing problems

When using polyester resins, styrene vapors are released. These irritate the mucous membranes and the respiratory tract. Therefore the GefStoffV prescribes a maximum occupational exposure limit (AGW) of 86 mg / m³. In certain concentrations, an explosive mixture can even arise. During the further processing of GRP components (grinding, cutting, sawing) fine dusts and chips with glassy filaments as well as sticky dusts arise in considerable quantities. These affect human health and the functionality of machines and systems. The installation of effective extraction and filter systems is necessary so that occupational safety regulations can be complied with and economic efficiency can be guaranteed in the long term .

Disposal / recycling

GRP can be added to cement production as a substitute fuel, with the plastic component supplying energy and the glass component becoming part of the cement raw material. Neocomp GmbH has developed this process and is currently using it (as of September 2019).

See also

• Bulk molding compound
• Fiber composite
• Sheet molding compound

Web links

Commons : Fiberglass Reinforced Plastic  - Collection of Pictures, Videos and Audio Files

• Institute for Composite Materials GmbH
• AVK - Industrial Association for Reinforced Plastics e. V.

literature

• Detlef Jens: The classic yachts. Volume 2: The plastics revolution. Koehlers Verlagsgesellschaft, Hamburg 2007, ISBN 978-3-7822-0945-8 .
• Volker Türschmann: Without dust and without styrene fumes. In: Plastverarbeiter Online. Hüthig GmbH, May 26, 2011, accessed on April 11, 2016 . 

Individual evidence

1. ^ H. Schürmann: Constructing with fiber-plastic composites. Springer, 2005. ISBN 978-3-540-40283-1 .
2. ↑ AVK - Industrial Association for Reinforced Plastics e. V. (Hrsg.): Handbook fiber composite plastics. Vieweg + Teubner, 2010. ISBN 978-3-8348-0881-3 .
3. ↑ Ю.В.Апальков: Корабли ВМФ СССР. Том IV - Десантные и минно-тральные корабли. Saint Petersburg 2007, ISBN 978-5-8172-0135-2 , p. 111 and following
4. ↑ Options for recycling rotor blades from onshore wind turbines (PDF)  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. Background paper of the German Wind Energy Association ; accessed on February 4, 2018.  
5. ↑ Elmar Witten, Thomas Kraus, Michael Kühnel: Composites Market Report 2015. (PDF; 1.3 MB) In: avk-tv.de. AVK - Industrial Association for Reinforced Plastics , September 21, 2015, accessed on April 11, 2016 . 
6. ↑ Volker Türschmann, Christian Jakschik, Hans-Jürgen Rothe: Problem solutions in GRP production - Topic: Clean air in the manufacture of glass fiber reinforced plastic parts (GRP). (PDF) (No longer available online.) In: ult.de. ULT AG, March 2011, archived from the original on August 13, 2012 ; Retrieved April 11, 2016 . 
7. ↑ Answer to the oral question: How do you dispose of a wind turbine? Lower Saxony Institute for the Environment, Energy, Building and Climate Protection, June 15, 2017, accessed on September 23, 2019.
8. ↑ Simon Schomäcker: Recycling of glass fiber plastic: Wind turbines become road surfaces . Deutschlandfunk , February 10, 2017; accessed on September 23, 2019