Editing Pre-preg (section)

{{Short description|Composite material}}
'''Pre-preg''' is a [[Composite material|composite]] material made from "pre-impregnated" [[Fiber-reinforced composite|fiber]]s and a ''partially [[Curing (chemistry)|cured]]'' [[Polymer matrix composite|polymer matrix]], such as [[epoxy]] or [[Phenol formaldehyde resin|phenolic]] resin, or even [[thermoplastic]] mixed with liquid rubbers or [[Resin|resins]].<ref>{{Cite book|last=Chawla|first=Krishan K.|url=http://link.springer.com/10.1007/978-0-387-74365-3|title=Composite Materials|date=2012|publisher=Springer New York|isbn=978-0-387-74364-6|location=New York, NY|language=en|doi=10.1007/978-0-387-74365-3|bibcode=2012coma.book.....C|s2cid=199491314}}</ref> The fibers often take the form of a [[weaving|weave]] and the matrix is used to bond them together and to other components during manufacture. The [[thermosetting polymer|thermoset]] matrix is only partially cured to allow easy handling; this [[B-staging|B-Stage material]] requires cold storage to prevent complete curing.  B-Stage pre-preg is always stored in cooled areas since heat accelerates complete polymerization. Hence, composite structures built of pre-pregs will mostly require an oven or [[Autoclave (industrial)|autoclave]] to cure. The main idea behind a pre-preg material is the use of [[Anisotropy|anisotropic]] mechanical properties along the fibers, while the polymer matrix provides filling properties, keeping the fibers in a single system. 
[[File:Thermoplastic Prepreg.jpg|alt=Thermoplastic CF/PEEK Prepreg|thumb|Thermoplastic CF/PEEK Prepreg]] 

Pre-preg allows one to impregnate the fibers on a flat workable surface, or rather in an industrial process, and then later form the impregnated fibers to a shape which could prove to be problematic for the hot injection process. Pre-preg also allows one to impregnate a bulk amount of fiber and then store it in a cooled area (below 20&nbsp;°C) for an extended period of time to cure later. The process can also be time consuming in comparison to the hot injection process and the added value for pre-preg preparation is at the stage of the material supplier.