Thermosetting precursors materials viscose

Carbon fibers can be produced from a wide variety of precursors in the range from natural materials to various thermoplastic and thermosetting precursors Materials, such as Polyacrylonitrile (PAN), mesophase pitch, petroleum, coal pitches, phenolic resins, polyvinylidene chloride (PVDC), rayon (viscose), etc. [42-43], About 90% of world s total carbon fiber productions are polyacrylonitrile (PAN)-based. To make carbon fibers from PAN precursor, PAN-based fibers are generally subjected to four pyrolysis processes, namely oxidation stabilization, carbonization and graphitiza-tion or activation they will be explained in following sections later [43]. 

The matrix allows the necessary positioning of the fibers, transfers the load to the fibers and distributes the stress among them, and is also responsible for protecting the reinforcement from the environment. However, the matrix is often the weakest component of a composite. One important parameter for the material properties is the fiber-matrix interface (or interphase), which guarantees the stress transfer from fiber to fiber via the matrix. The interface/interphase is a finite thin layer with its own (very often unknown) physical and chemical properties that depend on the fiber-matrix combination. Because of the low viscosity of the thermoset precursors, they wet the reinforcement better than a thermoplastic polymer. 

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