Commingled yarns

Aramid fiber is also used in production of reinforced thermoplastics (RTPs), as commingled yarns or a hybrid yarn or fabric, suitable for high drapabihty and coping with very sharp fillet radii, and in specialty tires. 

Commingled yarn ko- mig-gol, ka- (ca. 1626) V. In aerospace textiles, two or more continuous multifilament yarns, the filaments of which have been intermixed with each other without adding twist or otherwise disturbing parallel relationship of the combined filaments. Usually consists of a reinforcing yam, such as graphite or glass, and a thermoplastic matrix yarn. 

Table 1 Properties of monoaxial and biaxial warp knits of split-film and commingled yarns compared to woven fabrics of commingled yarns [5]...

Table 2 Specifications of GF/PP commingled yarn systems studied...

Svensson, N., Shishoo, R. and Gilchrist, M. (1998) Manufacturing of thermoplastic composite from commingled yarns - a review, /. Thermoplast. Composite Mater., 11, 22-56. 

A complex shaped-reinforced thermoplastic composite part made of commingled yarns with an integrated sensor... 

Material and process parameters influences the impregnation time. For commingled yarns (identical to all semi-finished products) the process parameters are temperature, maximum pressure, pressure rate and time. ... 

The winding process per se is equal to the commingled yarns and fully consolidated winding process. Heating technologies where reflection is possible by the filaments cannot be used with pre-melted powder filaments. Due to different heat absorptions (polymer and fibers) a homogeneous temperature cannot be reached. 

Nonreactive thermoplastic pultrusion utilizes completely polymerized plastics in various preprocessed states such as powder, granulates, filaments, or solutions. The use of preimpregnated fibers is advised due to short flow paths. These preimpregnated fibers can be fed into the pultruder as commingled yarns, thermoplastically coated yarns or tapes. Since impregnation is already done, no impregnation device is needed. Instead, due to the low thermal conductivity of the matrix material and its limited deterioration temperature. 

Wakeman W D, Zingraff L, Bourban P E and Manson J A E (2006) Stamp forming of carbon fiber/PA12 composites - A comparison of a reactive impregnation process and a commingled yarn system. Comp Sci Tech 66 19-35. 

Bernet, N., Wakeman, M.D., Bourban, P.-E., and Manson, ].-A.E. (2002) An integrated cost and consolidation model for commingled yarn based composites. Composites Part A, A 33, 495-506. 

Thanomsilp, C. and Hogg, P.). (2003) Penetration impact resistance of hybrid composites based on commingled yarn fabrics. Compos. Sci. Technol, 467-482. 

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