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The drawing and ultimate tensile properties of the modified PA 6 (MPA) fiber specimens prepared at varying drawing temperature were systematically investigated, wherein the MPA resins were prepared by reactive extrusion of PA 6 with the compatibilizer precursor (CP). At any fixed drawing temperature, the achievable draw ratio (D ra ) values of MPA as-spun fiber specimens increase initially with increasing CP contents, and then approach a maximum value, as their CP contents are close to the 5 wt% optimum value. The maximum D ra values obtained for MPA asspun fiber specimens prepared at the optimum CP content reach another maximum as their drawing temperatures approach the optimum drawing temperature at 1208C. The tensile and birefringence values of PA 6 and MPA fiber specimens improve consistently as their draw ratios increase. Similar to those found for their achievable drawing properties, the ultimate tensile and birefringence values of MPA fiber specimens approach a maximum value, as their CP contents and drawing temperatures approach the 5 wt% and 1208C optimum values, respectively. Investigations including Fourier transform infrared, melt shear viscosity, gel content, thermal and wide angle X-ray diffraction experiments were performed on the MPA resin and/or fiber specimens to clarify the optimum CP content and possible deformation mechanisms accounting for the interesting drawing, birefringence, and ultimate tensile properties found for the MPA fiber specimens prepared in this study. POLYM. ENG. SCI.,

The effects of calcium chloride (CaCl2) on polyamide 6 (PA6) electrospun fibers were investigated on this study. The interaction between CaCl2 and PA6 could affect the crystaline of PA6. XRD, DSC and FTIR revealed that the crystaline of PA6 reduced with increasing CaCl2. Moreover, the addition of CaCl2 could modify PA6 spinning solution properties, i.e., conductivity, surface tension and viscosity. The interaction between CaCl2 and PA6 has an important influence on morphological appearance and sizes of the resulting PA6 electrospun fibers.

The Al/Ni multilayer composite with highly exothermic reactions and good plasticity was fabricated by electrodeposition and hot press bonding process. The Al/Ni multilayer composite consisted of the microscale Al and Ni layers. The Ni layers were electroplated on Al foils for a certain time and DC current, and then a mounts of deposited foils were stacked and combined as a whole bulk Al/Ni multilayer composite. In this study, the microstructure evolution, phase transformation, exothermic heat and bending property of the Al/Ni multilayer composite during various hot press bonding were studied by SEM, XRD, DSC and bending test. Under the hot press bonding condition of 400°C and 1h, the exothermic heat, the bending strength and the bending displacement reached 916J/g, 614.5MPa and 4mm, respectively. The results showed that by the increasing time of hot press bonding, the bending displacement of the Al/Ni multilayer composite improved firstly and then declined sharply. It was also found that when the time of hot press bonding increased, the bending strength and the exothermic heat decreased simultaneously, owing to the nucleation and growth of the Al3Ni phases in the interfaces between Al and Ni layers.