Roth Composite Machinery laboratory line produces minimal surface weight prepregs
Roth Composite Machinery (Steffenberg, Germany) has announced that during current trials of its Prepreg Laboratory Line it has produced lightweight prepregs with a fiber surface weight of 75 g/m². The test was conducted at a process speed of 15 m/min. Roth Composite Machinery used 12 K carbon fibers having a fineness of 800 tex. Hot-melt epoxy was used as a matrix material. According to the company, prepregs with a resin surface weight of 25 g/m² and a width of 255 mm were produced. The Laboratory Line currently offers a fiber spreading unit with a working width of up to 600 mm.
In consultation with Roth Composite Machinery, business partners and raw material producers have the opportunity to carry out optimization or processing tests for their current matrix systems or for new systems, fibers and fabrics without having to interrupt their production processes. The company’s Prepreg Laboratory Line can process duromers as well as thermoplastic matrix systems up to 400°C. Roth’s process uses the Rothabow technique and is based on calendering technology, using two calenders. Possible trials can be conducted with thermoplastic matrix materials but also with duromers with layings or fabrics of all kinds of fiber systems such as carbon, glass or aramid.
Roth is able to produce multilayer composite materials made of fabrics, fibers and films using the laboratory line. A powder dosing unit for the processing of powder or granulate instead of a foil can be integrated. Roth offers the comma blade or the Foulard method as application systems for the matrix, yet the modular construction and the movable application unit enable the use of alternative, customer-specific application systems. The plant offers a spool creel with 80 spool positions, eight unwinders, three rewinders as well as a special fiber spreading unit. Measuring systems for coating thickness measurements or surface inspections, can easily be integrated.
Depending on the layers and the characteristics of the fiber materials, prepregs in all conceivable thicknesses can be manufactured using the line. Test runs for coating and laminating processes are also possible. Roth Composite Machinery offers direct and indirect coating methods by means of comma blades, impregnations by using the Foulard system and squeezing rollers as well as multilayer laminations with pre-tempering systems via surface heating or infrared radiation.
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