Technora

Abstract: The mechanical and dynamic mechanical properties of thermoplastic polyurethane (TPU) elastomers reinforced with two types of aramid short fibers, m-aramid (Teijin-Conex) and copoly(p-aramid) (Technora), were investigated in this study with respect to the fiber loading. In general, both types of composites exhibited very similar stress–strain behaviors, except that Technora–TPU was stronger than Conex–TPU. This was primarily due to the intrinsic strength of the reinforcing fibers. Both types of fibers reinforced TPU effectively without any surface treatment. This could be attributed to good fiber–matrix interactions, which were revealed by the broadening of the tan δ peak in dynamic mechanical analysis. Furthermore, the morphologies of cryogenically fractured surfaces of the composites and extracted fibers, investigated with scanning electron microscopy, revealed possible polar–polar interactions between the aramid fibers and TPU matrices. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1059–1067, 2003

Abstract: The cut resistance of organic and inorganic high-performance single fibers has been studied. Several fiber types were examined, including Kevlar, Twaron, Vectran, Technora, Zylon, Dyneema, carbon f...

Abstract: The research work reported in this paper involves investigation of the tensile behavior of fiber-reinforced polymer (FRP) ground anchors. Variables of the tests on the anchor models were anchor fixed length, tendon type, and tendon constituent. Sixteen monorod and four multirod grouted aramid FRP (AFRP) (Arapree and Technora) and carbon FRP (CFRP) (CFCC and Leadline) anchors were tested according to standard methods of tensile tests and sustained load tests under different load levels. Test results indicated that AFRP Arapree and Technora monorod anchors showed higher displacement and slip in comparison with CFRP CFCC and Leadline anchors. Technora anchors failed because of the detaching of winding fibers from the core of the rod. CFRP anchors had a higher tensile capacity and lower creep displacement than AFRP anchors. All the tested CFRP monorod and FRP multirod anchors with a 1,000-mm fixed length appeared to have an acceptable tensile behavior according to existing codes. Creep behavior appeared to co...

Abstract: The authors discuss the comparison of aramid (Technora by Teijin)/epoxy and glass/epoxy composites for multi-layer PWB (Printed Wiring Boards) in relation to blind via laser drilling. A CO2 laser with a maximum attainable power of 100 W is used. The spot diameter is 0.3 mm. The layer build up has a thickness of 0.3 mm with the outer copper etched. The blind vias are formed by laser irradiation from the outer layer side, since the base copper foil (inner copper thickness 18 μm) tends to reflect light strongly below the ablation threshold of copper. First, SEM observations of rim quality were carried out. The surface appears uneven due to melted glass fibers when using glass/epoxy materials, while it exhibits little residual fibers when aramid/epoxy materials are used. Second, conditions which are promising for the formation of blind via holes were researched. It was found that a few pulses with irradiation time of 0.5–2.0 ms per pulse are needed for completing a blind via hole. However, it was shown that only half the number of pulses is required with an aramid/epoxy composite. The reduction in fabrication time is significant, since a typical multi-layer panel has thousands of via holes. Finally, it is clear that the laser-drilled via hole has a uniform taper to the sidewall. There is better metallization with this type of hole than one with no taper of the sidewall. Additionally, the surface roughness on the sidewall is smaller with an aramid/epoxy composite than a glass/epoxy one. Therefore, the laser via formation method for multi-layer PWBs of aramid/epoxy is also effective from the viewpoint of plating reliability in circuit registration.