Spinning (polymers)

Spinning is manufacturing process for creating polymer fibers. It is a specialized form of extrusion that uses a spinneret to form multiple continuous filaments. There are four types of spinning: wet, dry, melt, and gel spinning.[1]



First, the polymer being spun must be converted into a fluid state. If the polymer is a thermoplastic then it is just melted, if not then it may be dissolved in a solvent or chemically treated to form soluble or thermoplastic derivatives. The fluid polymer is then forced through the spinneret, where the polymer cools to a rubbery state, and then a solidified state.[1]

Wet spinning

Wet spinning is the oldest of the four processes. This process is used for polymers that need to be dissolved in a solvent to be spun. The spinneret is submerged in a chemical bath that causes the fiber to precipitate, and then solidify, as it emerges. The process gets its name from this "wet" bath. Acrylic, rayon, aramid, modacrylic, and spandex are produced via this process.[1]

Dry spinning

Dry spinning is also used for polymers that must be dissolved in solvent. It differs in that the solidification is achieved through evaporation of the solvent. This is usually achieved by a stream of air or inert gas. Because there is no precipitating liquid involved, the fiber does not need to be dried, and the solvent is more easily recovered. Acetate, triacetate, acrylic, modacrylic, polybenzimidazole fiber, spandex, and vinyon are produced via this process.[1]

Melt spinning

Melt spinning is used for polymers that can be melted. The polymer solidifies by cooling after being extruded from the spinneret. Nylon, olefin, polyester, saran, and sulfar are produced via this process.[1]

Extrusion spinning

Pellets or granules of the solid polymer are fed into an extruder. The pellets are compressed, heated and melted by an extrusion screw, then fed to a spinning pump and into the spinneret.

Direct spinning

The direct spinning process avoids the stage of solid polymer pellets. The polymer melt is produced from the raw materials, and then from the polymer finisher directly pumped to the spinning mill. Direct spinning is mainly applied during production of polyester fibers and filaments and is dedicated to high production capacity (>100 ton/day).

Gel spinning

Gel spinning, also known as dry-wet spinning, is used to obtain high strength or other special properties in the fibers. The polymer is in a "gel" state, only partially liquid, which keeps the polymer chains somewhat bound together. These bonds produce strong inter-chain forces in the fiber, which increase its tensile strength. The polymer chains within the fibers also have a large degree of orientation, which increases strength. The fibers are first air dried, then cooled further in a liquid bath. Some high strength polyethylene and aramid fibers are produced via this process.[1]

Electro spinning

Electro spinning uses an electrical charge to draw very fine (typically on the micro or nano scale) fibres from a liquid. Electrospinning shares characteristics of both electrospraying and conventional solution dry spinning[2] of fibers. The process does not require the use of coagulation chemistry or high temperatures to produce solid threads from solution. This makes the process particularly suited to the production of fibers using large and complex molecules. Electrospinning from molten precursors is also practiced; this method ensures that no solvent can be carried over into the final product

see also the main article on Electrospinning


Finally, the fibers are drawn to increase strength and orientation. This may be done while the polymer is still solidifying or after it has completely cooled.[1]

See also

  • Spinneret (polymers)


  1. ^ a b c d e f g Manufacturing: Synthetic and Cellulosic Fiber Formation Technology, http://www.fibersource.com/f-tutor/techpag.htm, retrieved 2008-11-19 .
  2. ^ Ziabicki, A. Fundamentals of fiber formation, John Wiley and Sons, London, 1976, ISBN 0-471-98220-2.

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Melt spinning — For the polymer fiber forming process, see Spinning (polymers). Melt spinning is a technique used for rapid cooling of liquids. A wheel is cooled internally, usually by water or liquid nitrogen, and rotated. A thin stream of liquid is then… …   Wikipedia

  • industrial polymers, major — Introduction       chemical compounds used in the manufacture of synthetic industrial materials.       In the commercial production of plastics, elastomers, man made fibres, adhesives, and surface coatings, a tremendous variety of polymers are… …   Universalium

  • Magic angle spinning — Magic angle spinning: The sample (blue) is rotating with high frequency inside the main magnetic field (B0). The axis of rotation is tilted by the magic angle θm with respect to the direction of B0. In nuclear magnetic resonance, magic angle… …   Wikipedia

  • fibre, man-made — Introduction       fibre whose chemical composition, structure, and properties are significantly modified during the manufacturing process. Man made fibres are spun and woven into a huge number of consumer and industrial products, including… …   Universalium

  • Nanopolymers — The word nano is derived from the Greek word for “dwarf”. It is the prefix for units of 10 9. In a nutshell, nanoscience is the study of the extremely tiny. Nanoscience is concerned with the study of the unique properties of matter at its nano… …   Wikipedia

  • Mathematics and Physical Sciences — ▪ 2003 Introduction Mathematics       Mathematics in 2002 was marked by two discoveries in number theory. The first may have practical implications; the second satisfied a 150 year old curiosity.       Computer scientist Manindra Agrawal of the… …   Universalium

  • Business and Industry Review — ▪ 1999 Introduction Overview        Annual Average Rates of Growth of Manufacturing Output, 1980 97, Table Pattern of Output, 1994 97, Table Index Numbers of Production, Employment, and Productivity in Manufacturing Industries, Table (For Annual… …   Universalium

  • Polyethylene terephthalate — PETE redirects here. For the first name, see Peter (disambiguation). For other uses, see Pete (disambiguation). Polyethylene terephthalate fibre IUPAC name …   Wikipedia

  • technology, history of — Introduction       the development over time of systematic techniques for making and doing things. The term technology, a combination of the Greek technē, “art, craft,” with logos, “word, speech,” meant in Greece a discourse on the arts, both… …   Universalium

  • Ultra high molecular weight polyethylene — (UHMWPE), also known as high modulus polyethylene (HMPE) or high performance polyethylene (HPPE), is a subset of the thermoplastic polyethylene. It has extremely long chains, with molecular weight numbering in the millions, usually between 2 and… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.