Long fiber reinforced compounds

IMMs with the proper screw designs process short or long fiber reinforced compounds. As an example with a suitable machine and... 

Long fiber reinforced compounds polyamides. Basic/mechanical/thermal properties ... 

Interim storage of the fiber composite material is realized in a heat accumulator, from which it is discharged in cycles by a ram, chopped into molding compound units by a cutter at the end of the accumulator, and transported on a discharge belt. The plasticized material produced in this way is transferred into a compression mold, then formed into a structural component in an extrasion process. The finishing steps are the same as in other CM methods used for long fiber-reinforced thermoplastics. 

Trdster S, Geiger O, Henning F, Eyerer P (2004) Added value for long-fiber reinforced thermoplastic components by in-line-compounding in the LFT-D-ILC process. SPE Paper 1121, ANTEC 2004, Chicago, IL... 

Hauptli, A. (2003) Direct processing of long fiber reinforced plastics selecting a feeding system. Plast. Addit. Compound., 5, 36-39. 

Compounding of long fiber reinforced thermoplastics (LFRTs) is very different from compounding short fiber or particle filled composites. Long fibers enhance properties such as impact strength and are finding great utility in a number of applications in the automotive, industrial, and sports markets. Most of these products use PP or polyamide (PA), but poly(ethylene tere-phthalate) (PET) and other resins are also used. 

Data on long-fiber glass-reinforced grades are for Verton compounds. To convert psi to pascals (Pa), multiply by 6.895 x 103. 

The growth of these materials is reflected in the number of polymers which are being glass reinforced. These include polypropylene, polystyrene, styrene acrylonitrile, nylon, polyethylene, acrylonitrile-butadiene-styrene, modified polyphenylene oxide, polycarbonate, acetal, polysulfone, polyurethane, poly (vinyl chloride), and polyester. In addition, the reinforced thermoplastics available now include long-fiber compounds, short-fiber compounds, super concentrates for economy, a combination of long and short fibers, and blends of polymer and fibrous glass. 

The matrix can be either a thermoset or thermoplastic. The oldest and still widest used material for compression molded products is phenolic. The thermoset materials used to manufacture fiber reinforced compression molded articles is unsaturated polyester sheet or bulk, reinforced with glass fibers, known as sheet molding compound (SMC) or bulk molding compound (BMC). In SMC, the 25 mm long reinforcing fibers are randomly oriented in the plane of the sheet and make up for 20-30% of the molding compound s volume fraction. 

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