Richard Kafue Okine

Composites of stretch broken aligned fibers of carbon and glass reinforced resin

A coating of a viscous lubricant applied prior to stretch-breaking permits forming slivers of stretch-broken carbon fibers. When an anti-static ingredient is added to the viscous lubricant cohesive slivers of stretch-broken glass fibers can be formed. Composites of matrix resin reinforced with these slivers exhibit high strength, tensile stiffness, and good formability.

Transient rheological behavior of a long discontinuous fiber‐melt system

The transient elongational behavior of a highly‐aligned 60% fiber volume fraction long‐discontinuous‐fiber filled poly‐ether‐ketone‐ketone (PEKK) melt system was investigated with a computer controlled extensional rheometer at 370 °C. Long discontinuous graphite fibers, 7 μm in diameter, and PEKK thermoplastic constituted the melt system. Experiments conducted under conditions to approximate controlled strain rate and controlled stress produced τ+E(t,e) and e−(t,τE) similar to a shear dominated flow of a non‐linear viscoelastic fluid. Increasing strain rate resulted in an increasing peak stress and in an increasing ratio between peak stress and plateau stress. Increasing controlled stress level resulted in decreasing elongational viscosity and increasing post‐elastic‐step strain rate. The ratio of apparent ηE/ηPEKK was 3.67×108 to 3.94×1010 for average strain rates from 6.81×10−7 to 1.49×10−3 s−1. A variable taper shear cell analysis provided the range of expected ηE/η, which agreed well at high stra...

Non-Linear response of a long, discontinuous fiber/melt system in elongational flows

AbstractThe authors investigated the transient elongational behavior of a highly-aligned 600% volume fraction long, discontinuous fiber filled poly-ether-ketone-ketone melt with a computer-controlled extensional rheometer at 370°C. Prior experiments at controlled strain rate and stress produced τE+ (t,

Process of making a consolidated part

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A method for forming structural panels having a core with thermoplastic resin facings with a decorative film adhered to one of the facings and panel formed thereby.

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Verfahren zur herstellung von bauplatten und so hergestellte platten

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