Polyacrylonitrile carbon fiber manufacture

MEC (London U.K. and Shanghai, China), an international engineering services company, was awarded a 25 million contract by China Worldbest Group Co. Ltd. (Changzhou, China) to engineer and construct a polyacrylonitrile (PAN) and carbon fiber production plant in Bengbu, a city in Anhui province, located in eastern mainland China. The plant will be the first combined polyacrylonitrile and carbon fiber manufacturing facility built in China. The operation will include production of PAN precursor, which then will be converted into carbon fiber tow at the same location. 

The property of mesophase that makes it suitable for carbon fiber and premium coke manufacture is that it forms ordered stmctures under stress which persist following carbonization. However, most carbon fiber production in the 1990s is based on polyacrylonitrile (PAN). 

Low density, carbon fiber-carbon binder composites are fabricated from a variety of carbon fibers, including fibers derived from rayon, polyacrylonitrile (PAN), isotropic pitch, and mesophase pitch. The manufacture, structure, and properties of carbon fibers have been thoroughly reviewed elsewhere [3] and. therefore, are... 

Synonyms and trade names cyanoethylene, 2-propenenitrile, vinyl cyanide Use and exposure Acrylonitrile is a colorless, man-made liquid with a sharp, onion- or garlic-like odor. It can be dissolved in water and evaporates quickly. Acrylonitrile is used principally as a monomer in the manufacture of synthetic polymers, polyacrylonitriles, acrylic fibers, and other chemicals such as plastics and synthetic rubber. A mixture of acrylonitrile and carbon tetrachloride was used as a pesticide in the past. - Acrylonitrile is highly flammable and toxic. It undergoes explosive polymerization. The... 

Acrylonitrile end uses The primary use for acrylonitrile is in the manufacture of polyacrylonitrile (PAN) for acrylic fiber, which finds extensive uses in apparel, household furnishings, and industrial markets and applications, such as carbon fiber. Other end-use markets such as nitrile rubber, styrene-acrylonitrile (SAN) copolymer and acrylonitrile-butadi-ene-styrene (ABS) terpolymers have extensive commercial and industrial applications as tough, durable synthetic rubbers and engineering plastics. Acrylonitrile is also used to manufacture adipinitrile, which is the feedstock used to make Nylon 6,6. 

Whereas carbon fibers with a low carbon content are formed predominantly from aliphatic raw materials (rayon), carbon fibers with a high carbon content are produced from aromatic feedstocks or easy-to-aromatize base materials. The most important raw materials for the manufacture of high-carbon fibers are polyacrylonitrile and mesophase pitch. 

Carbon fibers are made from many different feedstocks. The most important commercial fiber is made from polyacrylonitrile (PAN). It is four times stronger than steel, the same modulus or higher, and does not fail in creep or fatigue. These properties made the fiber attractive for aerospace applications initially, and later for sporting and industrial applications. Another important feedstock is pitch from refinery or steel-making operations, which leads to fibers with very high modulus and thermal and electrical conductivities. Properties of the fibers, and critical steps in their manufacture are described, together with structural characteristics and failure mechanisms. 

Carbon fibers are manufactured by pyrolysis and thermal treatment of organic precursor fibers, viz., rayon, polyacrylonitrile (PAN), or pitch. In pilot plant quantities, carbon fibers have been grown by chemical vapor deposition from an organic vapor such as methane or benzene in the laboratory, they have also been grown by physical vapor deposition. 

Donnet JB, Bansal RC (1984) Carbon Fiber. Marcel Dekker, New York, NY, USA Saufi SM, Ismail AF (2002) Development and characterization of polyacrylonitrile (PAN) based carbon hollow fiber membrane. Songkianakarin J Sci Technol 24 (SuppI) 843-854 Schindler E, Maier F (1990) Manufacture of porous carbon membranes. US Patent 4,919,860 Yoneyama H, Nishihara Y (1990) Porous hollow carbon fiber film and method of manufacturing the same. EP Patent 0,394,449... 

Manufacturing techniques for producing carbon fibers are relatively complex and are not discussed. However, three different organic precursor materials are used rayon, polyacrylonitrile (PAN), and pitch. Processing techniques vary from precursor to precursor, as do the resultant fiber characteristics. 

Various surface pretreatments, often referred to as primers, are put on fibers and other textiles by the manufacturers to enhance subsequent bonding. Depending on the subsequent use of the textiles, the change in adhesion can be negative, nonexistent, or positive. In interlaminar shear strength tests of untreated and oxidative surface-treated polyacrylonitrile-based carbon fiber/epoxy composites the shear stress went from 14.9 to 22.1 MPa. 

For the present investigations, the reinforcement materials used were the polyacrylonitrile (PAN) based carbon fiber (PANEX 35) fabrics manufactured by ZOLTEK... 

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