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92-500: SRB-A is 2.5 meters in diameter, and 15.1 meters in length. Its casing is a carbon-fiber-reinforced polymer filament-wound composite. Two-axis attitude control is provided by electrically-actuated thrust vectoring. IHI led the development and production of the SRB-A, and various companies also participated in its development and production. For example, the composite fuel is BP-208, developed and manufactured by NOF Corporation ( ja ), and

184-410: A values than phenols and therefore do not form alcoholate ions in aqueous solutions. The base catalysed reaction of an acyl chloride with an alcohol may also be carried out in one phase using tertiary amines (e. g. triethylamine , Et 3 N) or pyridine as acid acceptors: [REDACTED] While acyl chloride-based polyesterifications proceed only very slowly at room temperature without a catalyst,

276-433: A cellophane -like polyester lining for their underground brood cells earning them the nickname "polyester bees". The family of synthetic polyesters comprises Depending on the chemical structure, polyester can be a thermoplastic or thermoset . There are also polyester resins cured by hardeners; however, the most common polyesters are thermoplastics. The OH group is reacted with an Isocyanate functional compound in

368-623: A cloth with blended properties. Cotton -polyester blends can be strong, wrinkle- and tear-resistant, and reduce shrinking. Synthetic fibers using polyester have high water, wind, and environmental resistance compared to plant-derived fibers. They are less fire-resistant and can melt when ignited. Liquid crystalline polyesters are among the first industrially used liquid crystal polymers . They are used for their mechanical properties and heat-resistance. These traits are also important in their application as an abradable seal in jet engines. Polyesters can contain one ester linkage per repeat unit of

460-438: A vacuum bag can be used. A fiberglass, carbon fiber, or aluminum mold is polished and waxed, and has a release agent applied before the fabric and resin are applied, and the vacuum is pulled and set aside to allow the piece to cure (harden). There are three ways to apply the resin to the fabric in a vacuum mold. The first method is manual and called a wet layup, where the two-part resin is mixed and applied before being laid in

552-436: A 2 component system producing coatings which may optionally be pigmented. Polyesters as thermoplastics may change shape after the application of heat. While combustible at high temperatures, polyesters tend to shrink away from flames and self-extinguish upon ignition. Polyester fibers have high tenacity and E-modulus as well as low water absorption and minimal shrinkage in comparison with other industrial fibers. Increasing

644-401: A 2/2 weave. The process by which most CFRPs are made varies, depending on the piece being created, the finish (outside gloss) required, and how many of the piece will be produced. In addition, the choice of matrix can have a profound effect on the properties of the finished composite. Many CFRP parts are created with a single layer of carbon fabric that is backed with fiberglass. A tool called

736-437: A central wing-box made of CFRP; it is the first to have a smoothly contoured wing cross-section instead of the wings being partitioned span-wise into sections. This flowing, continuous cross section optimises aerodynamic efficiency. Moreover, the trailing edge, along with the rear bulkhead, empennage , and un-pressurised fuselage are made of CFRP. However, many delays have pushed order delivery dates back because of problems with

828-447: A chopper gun is used to quickly create these composite parts. Once a thin shell is created out of carbon fiber, the chopper gun cuts rolls of fiberglass into short lengths and sprays resin at the same time, so that the fiberglass and resin are mixed on the spot. The resin is either external mix, wherein the hardener and resin are sprayed separately, or internal mixed, which requires cleaning after every use. Manufacturing methods may include

920-466: A core. Applications for CFRPs include the following: The Airbus A350 XWB is built of 53% CFRP including wing spars and fuselage components, overtaking the Boeing 787 Dreamliner , for the aircraft with the highest weight ratio for CFRP, which is 50%. This was one of the first commercial aircraft to have wing spars made from composites. The Airbus A380 was one of the first commercial airliners to have

1012-407: A finish on high-quality wood products such as guitars , pianos , and vehicle/yacht interiors. Thixotropic properties of spray-applicable polyesters make them ideal for use on open-grain timbers, as they can quickly fill wood grain, with a high-build film thickness per coat. It can be used for fashionable dresses, but it is most admired for its ability to resist wrinkling and shrinking while washing

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1104-704: A high melting point and low solubility. The named properties are in particular based on a high percentage of aromatic carbons in the polymer backbone which produces a certain stiffness. ⁠ Approaches for an improvement of processability include the incorporation of flexible spacers into the backbone, the attachment of stable pendent groups or the incorporation of non-symmetrical structures.⁠ Flexible spacers include, for example, ether or hexafluoroisopropylidene, carbonyl or aliphatic groups like isopropylidene; these groups allow bond rotation between aromatic rings. Less symmetrical structures, for example, based on meta - or ortho -linked monomers, introduce structural disorder, decreasing

1196-590: A low reactivity with carboxylic acids and cannot be polymerized via direct acid alcohol-based polyesterification. ⁠ In the case of PET production, however, the direct process has several advantages, in particular a higher reaction rate, a higher attainable molecular weight, the release of water instead of methanol and lower storage costs of the acid when compared to the ester due to the lower weight. [REDACTED] Transesterification : An alcohol-terminated oligomer and an ester-terminated oligomer condense to form an ester linkage, with loss of an alcohol. R and R' are

1288-505: A mold, with epoxy either pre-impregnated into the fibers (also known as pre-preg ) or "painted" over it. High-performance parts using single molds are often vacuum-bagged and/or autoclave -cured, because even small air bubbles in the material will reduce strength. An alternative to the autoclave method is to use internal pressure via inflatable air bladders or EPS foam inside the non-cured laid-up carbon fiber. For simple pieces of which relatively few copies are needed (one or two per day),

1380-432: A number of field applications strengthening concrete, masonry, steel, cast iron, and timber structures. Their use in industry can be either for retrofitting to strengthen an existing structure or as an alternative reinforcing (or prestressing) material instead of steel from the outset of a project. Retrofitting has become the increasingly dominant use of the material in civil engineering, and applications include increasing

1472-422: A refinery in a one-step process. Capture and reuse of the carbon and monomers is then possible. CFRPs can also be milled or shredded at low temperature to reclaim the carbon fiber; however, this process shortens the fibers dramatically. Just as with downcycled paper, the shortened fibers cause the recycled material to be weaker than the original material. There are still many industrial applications that do not need

1564-720: A single carbon fiber with diameter of 5–7 μm is sealed in a glass capillary. At the tip the capillary is either sealed with epoxy and polished to make carbon-fiber disk microelectrode or the fiber is cut to a length of 75–150 μm to make carbon-fiber cylinder electrode. Carbon-fiber microelectrodes are used either in amperometry or fast-scan cyclic voltammetry for detection of biochemical signalling. CFRPs are now widely used in sports equipment such as in squash, tennis, and badminton racquets, sport kite spars, high-quality arrow shafts, hockey sticks, fishing rods, surfboards , high end swim fins, and rowing shells . Amputee athletes such as Jonnie Peacock use carbon fiber blades for running. It

1656-467: A specific material , it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include naturally occurring chemicals, such as in plants and insects , as well as synthetics such as polybutyrate . Natural polyesters and a few synthetic ones are biodegradable , but most synthetic polyesters are not. Synthetic polyesters are used extensively in clothing. Polyester fibers are sometimes spun together with natural fibers to produce

1748-516: Is >1000 tonnes/day and can easily reach 2500 tonnes/day. Besides the above-mentioned large processing units to produce staple fiber or yarns, there are ten thousands of small and very small processing plants, so that one can estimate that polyester is processed and recycled in more than 10 000 plants around the globe. This is without counting all the companies involved in the supply industry, beginning with engineering and processing machines and ending with special additives, stabilizers and colors. This

1840-439: Is a gigantic industry complex and it is still growing by 4–8% per year, depending on the world region. Synthesis of polyesters is generally achieved by a polycondensation reaction. The general equation for the reaction of a diol with a diacid is: Polyesters can be obtained by a wide range of reactions of which the most important are the reaction of acids and alcohols, alcoholysis and or acidolysis of low-molecular weight esters or

1932-460: Is carried out at lower temperatures than the equilibrium methods; possible types are the high-temperature solution condensation, amine catalysed and interfacial reactions. In addition, the use of activating agents is counted as non-equilibrium method. The equilibrium constants for the acyl chloride-based condensation yielding yielding arylates and polyarylates are very high indeed and are reported to be 4.3 × 10 and 4.7 × 10 , respectively. This reaction

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2024-432: Is circumvented by the mild temperatures of interfacial polycondensation. The procedure is applied to the commercial production of bisphenol-A-based polyarylates like Unitika's U-Polymer. Water could be in some cases replaced by an immiscible organic solvent (e. g. in the adiponitrile / carbon tetrachloride system). The procedure is of little use in the production of polyesters based on aliphatic diols which have higher p K

2116-410: Is counted as commodity plastic . There are several reasons for the importance of polyethylene terephthalate: In the following table, the estimated world polyester production is shown. Main applications are textile polyester, bottle polyester resin, film polyester mainly for packaging and specialty polyesters for engineering plastics. After the first stage of polymer production in the melt phase,

2208-409: Is dependent on the fiber orientation and machining condition of the cutting process. To reduce tool wear various types of coated tools are used in machining CFRP and CFRP-metal stack. The primary element of CFRPs is a carbon filament ; this is produced from a precursor polymer such as polyacrylonitrile (PAN), rayon , or petroleum pitch . For synthetic polymers such as PAN or rayon, the precursor

2300-438: Is first spun into filament yarns, using chemical and mechanical processes to initially align the polymer chains in a way to enhance the final physical properties of the completed carbon fiber. Precursor compositions and mechanical processes used during spinning filament yarns may vary among manufacturers. After drawing or spinning, the polymer filament yarns are then heated to drive off non-carbon atoms ( carbonization ), producing

2392-426: Is generally stated as being higher than 150 °C, whereas engineering plastics (such as polyamide or polycarbonate) are often defined as thermoplastics that retain their properties above 100 °C. ⁠ Commodity plastics (such as polyethylene or polypropylene) have in this respect even greater limitations, but they are manufactured in great amounts at low cost. Poly(ester imides ) contain an aromatic imide group in

2484-518: Is mitigated by the material's unsurpassed strength-to-weight ratio, and low weight is essential for high-performance automobile racing. Race-car manufacturers have also developed methods to give carbon fiber pieces strength in a certain direction, making it strong in a load-bearing direction, but weak in directions where little or no load would be placed on the member. Conversely, manufacturers developed omnidirectional carbon fiber weaves that apply strength in all directions. This type of carbon fiber assembly

2576-619: Is most widely used in the "safety cell" monocoque chassis assembly of high-performance race-cars. The first carbon fiber monocoque chassis was introduced in Formula One by McLaren in the 1981 season. It was designed by John Barnard and was widely copied in the following seasons by other F1 teams due to the extra rigidity provided to the chassis of the cars. Many supercars over the past few decades have incorporated CFRPs extensively in their manufacture, using it for their monocoque chassis as well as other components. As far back as 1971,

2668-413: Is much more difficult to process and more expensive. Despite their high initial strength-to-weight ratios, a design limitation of CFRPs are their lack of a definable fatigue limit . This means, theoretically, that stress cycle failure cannot be ruled out. While steel and many other structural metals and alloys do have estimable fatigue or endurance limits, the complex failure modes of composites mean that

2760-409: Is often a thermoset resin such as epoxy , but other thermoset or thermoplastic polymers, such as polyester , vinyl ester , or nylon, are sometimes used. The properties of the final CFRP product can be affected by the type of additives introduced to the binding matrix (resin). The most common additive is silica , but other additives such as rubber and carbon nanotubes can be used. Carbon fiber

2852-417: Is particularly useful for when high melting and poorly soluble dicarboxylic acids are used. In addition, alcohols as condensation product are more volatile and thereby easier to remove than water. The high-temperature melt synthesis between bisphenol diacetates and aromatic dicarboxylic acids or in reverse between bisphenols and aromatic dicarboxylic acid diphenyl esters (carried out at 220 to 320 °C upon

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2944-473: Is produced at one site starting from crude oil or distillation products in the chain oil → benzene → PX → PTA → PET melt → fiber/filament or bottle-grade resin. Such integrated processes are meanwhile established in more or less interrupted processes at one production site. Eastman Chemicals were the first to introduce the idea of closing the chain from PX to PET resin with their so-called INTEGREX process. The capacity of such vertically integrated production sites

3036-506: Is several times stronger and tougher than typical CFRPs and is used in the Lockheed Martin F-35 Lightning II as a structural material for aircraft. CNRP still uses carbon fiber as the primary reinforcement, but the binding matrix is a carbon nanotube-filled epoxy. Polyester Polyester is a category of polymers that contain one or two ester linkages in every repeat unit of their main chain. As

3128-646: Is significantly improved if a thin layer of carbon fibers is moulded near the surface because a dense, compact layer of carbon fibers efficiently reflects heat. CFRPs are being used in an increasing number of high-end products that require stiffness and low weight, these include: CFRPs have a long service lifetime when protected from the sun. When it is time to decommission CFRPs, they cannot be melted down in air like many metals. When free of vinyl (PVC or polyvinyl chloride ) and other halogenated polymers, CFRPs can be thermally decomposed via thermal depolymerization in an oxygen-free environment. This can be accomplished in

3220-442: Is sometimes referred to as graphite-reinforced polymer or graphite fiber-reinforced polymer ( GFRP is less common, as it clashes with glass-(fiber)-reinforced polymer ). CFRP are composite materials . In this case the composite consists of two parts: a matrix and a reinforcement. In CFRP the reinforcement is carbon fiber, which provides its strength. The matrix is usually a thermosetting plastic, such as polyester resin, to bind

3312-401: Is the total composite modulus, V m {\displaystyle V_{m}} and V f {\displaystyle V_{f}} are the volume fractions of the matrix and fiber respectively in the composite, and E m {\displaystyle E_{m}} and E f {\displaystyle E_{f}} are the elastic moduli of

3404-470: Is thus often referred to as a 'non-equilibrium' polyesterification. Even though the acyl chloride based synthesis is also subject of reports in the patent literature, it is unlikely that the reaction is utilized on the production scale. The method is limited by the acid dichlorides' high cost, its sensitivity to hydrolysis and the occurrence of side reactions. The high temperature reaction (100 to > 300 °C) of an diacyl chloride with an dialcohol yields

3496-436: Is typical). As a consequence, only small cross-sectional areas of the material are used. Small areas of very high strength but moderate stiffness material will significantly increase strength, but not stiffness. CFRPs can also be used to enhance shear strength of reinforced concrete by wrapping fabrics or fibers around the section to be strengthened. Wrapping around sections (such as bridge or building columns) can also enhance

3588-412: Is used as a shank plate in some basketball sneakers to keep the foot stable, usually running the length of the shoe just above the sole and left exposed in some areas, usually in the arch. Controversially, in 2006, cricket bats with a thin carbon-fiber layer on the back were introduced and used in competitive matches by high-profile players including Ricky Ponting and Michael Hussey . The carbon fiber

3680-631: Is used as cushioning and insulating material in pillows, comforters, stuffed animals and characters, and upholstery padding. Polyester fabrics are highly stain-resistant since polyester is a hydrophobic material, making it hard to absorb liquids. The only class of dyes which can be used to alter the color of polyester fabric are what are known as disperse dyes . Polyesters are also used to make bottles, films, tarpaulin , sails ( Dacron ), canoes, liquid crystal displays , holograms , filters , dielectric film for capacitors , film insulation for wire and insulating tapes . Polyesters are widely used as

3772-849: Is used as the first stage of the Epsilon S. Carbon-fiber-reinforced polymer Carbon fiber-reinforced polymers ( American English ), carbon-fibre-reinforced polymers ( Commonwealth English ), carbon-fiber-reinforced plastics , carbon-fiber reinforced-thermoplastic ( CFRP , CRP , CFRTP ), also known as carbon fiber , carbon composite , or just carbon , are extremely strong and light fiber-reinforced plastics that contain carbon fibers . CFRPs can be expensive to produce, but are commonly used wherever high strength-to-weight ratio and stiffness (rigidity) are required, such as aerospace, superstructures of ships, automotive, civil engineering, sports equipment, and an increasing number of consumer and technical applications. The binding polymer

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3864-639: The Citroën SM offered optional lightweight carbon fiber wheels. Use of the material has been more readily adopted by low-volume manufacturers who used it primarily for creating body-panels for some of their high-end cars due to its increased strength and decreased weight compared with the glass-reinforced polymer they used for the majority of their products. CFRPs have become a notable material in structural engineering applications. Studied in an academic context as to their potential benefits in construction, CFRPs have also proved themselves cost-effective in

3956-588: The LGM-118 Peacekeeper MIRV -capable intercontinental ballistic missile (ICBM). The original SRB-A was developed for the H-IIA rocket, and was used on its first 6 flights. It was derived from the SRB used on H-II . During the sixth launch of an H-IIA, one of the boosters failed to separate due to a leak of hot gasses eroding the detachment points, causing the rocket to fail to reach orbit. SRB-A2

4048-591: The brittle nature of CFRPs, in contrast to the ductility of steel. Though design codes have been drawn up by institutions such as the American Concrete Institute , there remains some hesitation among the engineering community about implementing these alternative materials. In part, this is due to a lack of standardization and the proprietary nature of the fiber and resin combinations on the market. Carbon fibers are used for fabrication of carbon-fiber microelectrodes . In this application typically

4140-478: The ductility of the section, greatly increasing the resistance to collapse under dynamic loading. Such 'seismic retrofit' is the major application in earthquake-prone areas, since it is much more economic than alternative methods. If a column is circular (or nearly so) an increase in axial capacity is also achieved by wrapping. In this application, the confinement of the CFRP wrap enhances the compressive strength of

4232-555: The SRB-3 has been greatly simplified compared to the SRB-A series, and the nozzle has been changed from a variable type to a fixed type. In the SRB-A series, the burn pattern was different when two or four boosters were used in the H-IIA/B and when used as the first stage of the Epsilon, but in the SRB-3, the burn pattern is the same when two or four boosters are used in the H3 and when the SRB-3

4324-448: The alcoholysis of acyl chlorides. The following figure gives an overview over such typical polycondensation reactions for polyester production. Furthermore, polyesters are accessible via ring-opening polymerization. [REDACTED] Azeotrope esterification is a classical method for condensation. The water formed by the reaction of alcohol and a carboxylic acid is continually removed by azeotropic distillation . When melting points of

4416-474: The amine accelerates the reaction in several possible ways, although the mechanism is not fully understood. However, it is known that tertiary amines can cause side-reactions such as the formation of ketenes and ketene dimers.⁠ [REDACTED] [REDACTED] Aliphatic polyesters can be assembled from lactones under very mild conditions, catalyzed anionically , cationically , metallorganically or enzyme-based. A number of catalytic methods for

4508-650: The aromatic parts of polyesters increases their glass transition temperature , melting temperature, thermostability , chemical stability, and solvent resistance. Polyesters can also be telechelic oligomers like the polycaprolactone diol (PCL) and the polyethylene adipate diol (PEA). They are then used as prepolymers . Thermally stable polymers, which generally have a high proportion of aromatic structures , are also called high-performance plastics . This application-oriented classification compares such polymers with engineering plastics and commodity plastics . The continuous service temperature of high-performance plastics

4600-426: The brittle fracture mechanics presents unique challenges to engineers in failure detection since failure occurs catastrophically. As such, recent efforts to toughen CFRPs include modifying the existing epoxy material and finding alternative polymer matrix. One such material with high promise is PEEK , which exhibits an order of magnitude greater toughness with similar elastic modulus and tensile strength. However, PEEK

4692-462: The carbon fiber, one of the components of the motor case, is T1000GB, developed and manufactured by Toray . On the other hand, in order to shorten the development time of the SRB-A, foreign technology was used for the molding process of the motor case. The composite motor case design is based on technology used on the Castor 120 motor by Alliant Techsystems , itself based on the first stage motor for

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4784-571: The chemical reaction between two primary raw materials: purified terephthalic acid (PTA) or dimethyl terephthalate (DMT) and monoethylene glycol (MEG). The production process includes the following steps: Polyethylene terephthalate , the polyester with the greatest market share, is a synthetic polymer made of purified terephthalic acid (PTA) or its dimethyl ester dimethyl terephthalate (DMT) and monoethylene glycol (MEG). With 18% market share of all plastic materials produced, it ranges third after polyethylene (33.5%) and polypropylene (19.5%) and

4876-407: The concrete. However, although large increases are achieved in the ultimate collapse load, the concrete will crack at only slightly enhanced load, meaning that this application is only occasionally used. Specialist ultra-high modulus CFRP (with tensile modulus of 420 GPa or more) is one of the few practical methods of strengthening cast iron beams. In typical use, it is bonded to the tensile flange of

4968-734: The copolymerization of epoxides with cyclic anhydrides have also recently been shown to provide a wide array of functionalized polyesters, both saturated and unsaturated. Ring-opening polymerization of lactones and lactides is also applied on the industrial scale. Numerous other reactions have been reported for the synthesis of selected polyesters, but are limited to laboratory-scale syntheses using specific conditions, for example using dicarboxylic acid salts and dialkyl halides or reactions between bisketenes and diols. Instead of acyl chlorides, so-called activating agents can be used, such as 1,1'-carbonyldiimidazole , dicyclohexylcarbodiimide , or trifluoroacetic anhydride . The polycondensation proceeds via

5060-796: The crystallinity. The generally poor processability of aromatic polymers (for example, a high melting point and a low solubility) also limits the available options for synthesis and may require strong electron-donating co-solvents like HFIP or TFA for analysis (e. g. H NMR spectroscopy ) which themselves can introduce further practical limitations. Fabrics woven or knitted from polyester thread or yarn are used extensively in apparel and home furnishings, from shirts and pants to jackets and hats, bed sheets, blankets, upholstered furniture and computer mouse mats. Industrial polyester fibers, yarns and ropes are used in car tire reinforcements, fabrics for conveyor belts, safety belts, coated fabrics and plastic reinforcements with high-energy absorption. Polyester fiber

5152-409: The desired component. The benefit is the speed of the entire process. Some car manufacturers, such as BMW, claimed to be able to cycle a new part every 80 seconds. However, this technique has a very high initial cost since the molds require CNC machining of very high precision. For difficult or convoluted shapes, a filament winder can be used to make CFRP parts by winding filaments around a mandrel or

5244-550: The fatigue failure properties of CFRPs are difficult to predict and design against; however emerging research has shed light on the effects of low velocity impacts on composites. Low velocity impacts can make carbon fibre polymers susceptible to damage. As a result, when using CFRPs for critical cyclic-loading applications, engineers may need to design in considerable strength safety margins to provide suitable component reliability over its service life. Environmental effects such as temperature and humidity can have profound effects on

5336-401: The final carbon fiber. The carbon fibers filament yarns may be further treated to improve handling qualities, then wound onto bobbins . From these fibers, a unidirectional sheet is created. These sheets are layered onto each other in a quasi-isotropic layup, e.g. 0°, +60°, or −60° relative to each other. From the elementary fiber, a bidirectional woven sheet can be created, i.e. a twill with

5428-495: The following: One method of producing CFRP parts is by layering sheets of carbon fiber cloth into a mold in the shape of the final product. The alignment and weave of the cloth fibers is chosen to optimize the strength and stiffness properties of the resulting material. The mold is then filled with epoxy and is heated or air-cured. The resulting part is very corrosion-resistant, stiff, and strong for its weight. Parts used in less critical areas are manufactured by draping cloth over

5520-415: The form of hydrogen embrittlement has been blamed for the gradual deterioration of the prestressing wires in many PCCP lines. Over the past decade, CFRPs have been used to internally line PCCP, resulting in a fully structural strengthening system. Inside a PCCP line, the CFRP liner acts as a barrier that controls the level of strain experienced by the steel cylinder in the host pipe. The composite liner enables

5612-440: The load capacity of old structures (such as bridges, beams, ceilings, columns and walls) that were designed to tolerate far lower service loads than they are experiencing today, seismic retrofitting, and repair of damaged structures. Retrofitting is popular in many instances as the cost of replacing the deficient structure can greatly exceed the cost of strengthening using CFRP. Applied to reinforced concrete structures for flexure,

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5704-419: The manufacture of these parts. Many aircraft that use CFRPs have experienced delays with delivery dates due to the relatively new processes used to make CFRP components, whereas metallic structures have been studied and used on airframes for decades, and the processes are relatively well understood. A recurrent problem is the monitoring of structural ageing, for which new methods are constantly investigated, due to

5796-568: The matrix and fibers respectively. The other extreme case of the elastic modulus of the composite with the fibers oriented transverse to the applied load can be found using the equation: The fracture toughness of carbon fiber reinforced plastics is governed by the mechanisms: 1) debonding between the carbon fiber and polymer matrix, 2) fiber pull-out, and 3) delamination between the CFRP sheets. Typical epoxy-based CFRPs exhibit virtually no plasticity, with less than 0.5% strain to failure. Although CFRPs with epoxy have high strength and elastic modulus,

5888-623: The matrix in CFRPs such as compressive, interlaminar shear, and impact properties. The epoxy matrix used for engine fan blades is designed to be impervious against jet fuel, lubrication, and rain water, and external paint on the composites parts is applied to minimize damage from ultraviolet light. Carbon fibers can cause galvanic corrosion when CRP parts are attached to aluminum or mild steel but not to stainless steel or titanium. Carbon Fiber Reinforced Plastics are very hard to machine, and cause significant tool wear. The tool wear in CFRP machining

5980-433: The mold and placed in the bag. The other one is done by infusion, where the dry fabric and mold are placed inside the bag while the vacuum pulls the resin through a small tube into the bag, then through a tube with holes or something similar to evenly spread the resin throughout the fabric. Wire loom works perfectly for a tube that requires holes inside the bag. Both of these methods of applying resin require hand work to spread

6072-423: The monomers are sufficiently low, a polyester can be formed via direct esterification while removing the reaction water via vacuum. [REDACTED] Direct bulk polyesterification at high temperatures (150 – 290 °C) is well-suited and used on the industrial scale for the production of aliphatic, unsaturated, and aromatic–aliphatic polyesters. Monomers containing phenolic or tertiary hydroxyl groups exhibit

6164-647: The need to re-true a wheel and the reduced mass reduces the moment of inertia of the wheel. CFRP spokes are rare and most carbon wheelsets retain traditional stainless steel spokes. CFRPs also appear increasingly in other components such as derailleur parts, brake and shifter levers and bodies, cassette sprocket carriers, suspension linkages, disc brake rotors, pedals, shoe soles, and saddle rails. Although strong and light, impact, over-torquing, or improper installation of CFRP components has resulted in cracking and failures, which may be difficult or impossible to repair. The fire resistance of polymers and thermo-set composites

6256-485: The polyester and hydrogen chloride. Under these relatively high temperatures the reaction proceeds rapidly without a catalyst: [REDACTED] The conversion of the reaction can be followed by titration of the evolved hydrogen chloride. A wide variety of solvents has been described including chlorinated benzenes (e.g. dichlorobenzene), chlorinated naphthalenes or diphenyls, as well as non-chlorinated aromatics like terphenyls, benzophenones or dibenzylbenzenes. The reaction

6348-415: The polyester family, based on the varying nature of the R group (see first figure with blue ester group). Polyesters occurring in nature include the cutin component of plant cuticles , which consists of omega hydroxy acids and their derivatives, interlinked via ester bonds, forming polyester polymers of indeterminate size. Polyesters are also produced by bees in the genus Colletes , which secrete

6440-461: The polyester melt with a high efficiency, high-output processing steps like staple fiber (50–300 tonnes/day per spinning line) or POY /FDY (up to 600 tonnes/day split into about 10 spinning machines) are meanwhile more and more vertically integrated direct processes. This means the polymer melt is directly converted into the textile fibers or filaments without the common step of pelletizing . We are talking about full vertical integration when polyester

6532-434: The polymer, as in polyhydroxyalkanoates like polylactic acid , or they may have two ester linkages per repeat unit, as in polyethylene terephthalate (PET). Polyesters are one of the most economically important classes of polymers, driven especially by PET, which is counted among the commodity plastics; in 2019 around 30.5 million metric tons were produced worldwide. There is a great variety of structures and properties in

6624-494: The polymer-based composites, including most CFRPs. While CFRPs demonstrate excellent corrosion resistance, the effect of moisture at wide ranges of temperatures can lead to degradation of the mechanical properties of CFRPs, particularly at the matrix-fiber interface. While the carbon fibers themselves are not affected by the moisture diffusing into the material, the moisture plasticizes the polymer matrix. This leads to significant changes in properties that are dominantly influenced by

6716-413: The product stream divides into two different application areas which are mainly textile applications and packaging applications. In the following table, the main applications of textile and packaging of polyester are listed. Abbreviations: A comparable small market segment (much less than 1 million tonnes/year) of polyester is used to produce engineering plastics and masterbatch . In order to produce

6808-406: The product. Its toughness makes it a frequent choice for children's wear. Polyester is often blended with other fibres like cotton to get the desirable properties of both materials. Cured polyesters can be sanded and polished to a high-gloss, durable finish. Polyester is typically produced through a process known as polymerization. For polyethylene terephthalate (PET), the production process involves

6900-436: The proportion of the carbon fibers relative to the polymer. The two different equations governing the net elastic modulus of composite materials using the properties of the carbon fibers and the polymer matrix can also be applied to carbon fiber reinforced plastics. The equation: is valid for composite materials with the fibers oriented in the direction of the applied load. E c {\displaystyle E_{c}}

6992-409: The reaction occurs at the interface under high-speed agitation near room temperature. [REDACTED] The procedure is used for the production of polyarylates (polyesters based on bisphenols), polyamides , polycarbonates , poly(thiocarbonate)s , and others. Since the molecular weight of the product obtained by a high-temperature synthesis can be seriously limited by side reactions, this problem

7084-414: The reinforcements together. Because CFRPs consist of two distinct elements, the material properties depend on these two elements. Reinforcement gives CFRPs their strength and rigidity, measured by stress and elastic modulus respectively. Unlike isotropic materials like steel and aluminum, CFRPs have directional strength properties. The properties of a CFRP depend on the layouts of the carbon fiber and

7176-483: The release of acetic acid) is, besides the acyl chloride based synthesis, the preferred route to wholly aromatic polyesters. In acylation , the acid begins as an acyl chloride , and thus the polycondensation proceeds with emission of hydrochloric acid (HCl) instead of water. The reaction between diacyl chlorides and alcohols or phenolic compounds has been widely applied to polyester synthesis and has been subject of numerous reviews and book chapters. ⁠ The reaction

7268-593: The repeat unit, the imide-based polymers have a high proportion of aromatic structures in the main chain and belong to the class of thermally stable polymers. Such polymers contain structures that impart high melting temperatures, resistance to oxidative degradation and stability to radiation and chemical reagents. Among the thermally stable polymers with commercial relevance are polyimides , polysulfones , polyetherketones , and polybenzimidazoles . Of these, polyimides are most widely applied. The polymers' structures result also in poor processing characteristics, in particular

7360-649: The resin evenly for a glossy finish with very small pin-holes. A third method of constructing composite materials is known as a dry layup. Here, the carbon fiber material is already impregnated with resin (pre-preg) and is applied to the mold in a similar fashion to adhesive film. The assembly is then placed in a vacuum to cure. The dry layup method has the least amount of resin waste and can achieve lighter constructions than wet layup. Also, because larger amounts of resin are more difficult to bleed out with wet layup methods, pre-preg parts generally have fewer pinholes. Pinhole elimination with minimal resin amounts generally require

7452-553: The section, both increasing the stiffness of the section and lowering the neutral axis , thus greatly reducing the maximum tensile stress in the cast iron. In the United States, prestressed concrete cylinder pipes (PCCP) account for a vast majority of water transmission mains. Due to their large diameters, failures of PCCP are usually catastrophic and affect large populations. Approximately 19,000 miles (31,000 km) of PCCP were installed between 1940 and 2006. Corrosion in

7544-709: The steel cylinder to perform within its elastic range, to ensure the pipeline's long-term performance is maintained. CFRP liner designs are based on strain compatibility between the liner and host pipe. CFRPs are more costly materials than commonly used their counterparts in the construction industry, glass fiber-reinforced polymers (GFRPs) and aramid fiber-reinforced polymers (AFRPs), though CFRPs are, in general, regarded as having superior properties. Much research continues to be done on using CFRPs both for retrofitting and as an alternative to steel as reinforcing or prestressing materials. Cost remains an issue and long-term durability questions still remain. Some are concerned about

7636-429: The strength of full-length carbon fiber reinforcement. For example, chopped reclaimed carbon fiber can be used in consumer electronics, such as laptops. It provides excellent reinforcement of the polymers used even if it lacks the strength-to-weight ratio of an aerospace component. In 2009, Zyvex Technologies introduced carbon nanotube-reinforced epoxy and carbon pre-pregs . Carbon nanotube reinforced polymer (CNRP)

7728-520: The thirteenth mission, as well as the H-IIB and as the first stage of Epsilon. Unlike the SRB-A, the composite motor case of the SRB-3 is manufactured using Japan's own technology, without using ATK's technology. The SRB-3 used in the H3 and Epsilon S rockets has one ton more propellant than the SRB-A series to increase its launch capability. To improve reliability and reduce cost, the separation mechanism of

7820-478: The two oligomer chains, R'' is a sacrificial unit such as a methyl group ( methanol is the byproduct of the esterification reaction). The term " transesterification " is typically used to describe hydroxy–ester, carboxy–ester, and ester–ester exchange reactions. The hydroxy–ester exchange reaction possesses the highest rate of reaction and is used for the production of numerous aromatic–aliphatic and wholly aromatic polyesters. The transesterification based synthesis

7912-718: The unusual multi-material and anisotropic nature of CFRPs. In 1968 a Hyfil carbon-fiber fan assembly was in service on the Rolls-Royce Conways of the Vickers VC10s operated by BOAC . Specialist aircraft designers and manufacturers Scaled Composites have made extensive use of CFRPs throughout their design range, including the first private crewed spacecraft Spaceship One . CFRPs are widely used in micro air vehicles (MAVs) because of their high strength-to-weight ratio. CFRPs are extensively used in high-end automobile racing. The high cost of carbon fiber

8004-407: The use of autoclave pressures to purge the residual gases out. A quicker method uses a compression mold , also commonly known as carbon fiber forging. This is a two (male and female), or multi-piece mold, usually made out of aluminum or steel and more recently 3D printed plastic. The mold components are pressed together with the fabric and resin loaded into the inner cavity that ultimately becomes

8096-422: The use of CFRPs typically has a large impact on strength (doubling or more the strength of the section is not uncommon), but only moderately increases stiffness (as little as 10%). This is because the material used in such applications is typically very strong (e.g., 3 GPa ultimate tensile strength , more than 10 times mild steel) but not particularly stiff (150 to 250 GPa elastic modulus, a little less than steel,

8188-510: Was a planned upgrade, intended to replace SRB-A on H-IIA. Following the 2003 failure, it was cancelled and its design improvements were merged into the SRB-A Improved. An improved version of SRB-A was developed following the 2003 incident. The nozzle was changed from a conical to a bell shape, to reduce thermal loading and erosion. Its thrust was also reduced slightly, and its burn time lengthened, to further decrease heating. This version

8280-514: Was also applied successfully to the preparation of highly crystalline and poorly soluble polymers which require high temperatures to be kept in solution (at least until a sufficiently high molecular weight was achieved). In an interfacial acyl chloride-based reaction, the alcohol (generally in fact a phenol) is dissolved in the form of an alkoxide in an aqueous sodium hydroxide solution , the acyl chloride in an organic solvent immiscible with water such as dichloromethane , chlorobenzene or hexane ,

8372-958: Was claimed to merely increase the durability of the bats, but it was banned from all first-class matches by the ICC in 2007. A CFRP bicycle frame weighs less than one of steel, aluminum, or titanium having the same strength. The type and orientation of the carbon-fiber weave can be designed to maximize stiffness in required directions. Frames can be tuned to address different riding styles: sprint events require stiffer frames while endurance events may require more flexible frames for rider comfort over longer periods. The variety of shapes it can be built into has further increased stiffness and also allowed aerodynamic tube sections. CFRP forks including suspension fork crowns and steerers, handlebars , seatposts , and crank arms are becoming more common on medium as well as higher-priced bicycles. CFRP rims remain expensive but their stability compared to aluminium reduces

8464-505: Was flown on the seventh through the thirteenth H-IIA. However, the nozzle erosion problem was still not fully solved, leading to the development of the SRB-A3 SRB-A3 is the current version, redesigned to provide higher performance and improve reliability. It is available in two variants, one producing high thrust at a short duration burn, and the other with a longer duration lower thrust burn. It has been used on all H-IIA flights past

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