Advanced Materials Research Vols. 87-88

Abstract: Aircraft tire is an important subassembly of aircraft, which is related to its safety tightly, especially for civil aircraft. Moreover, hydroplaning of aircraft tires is often a contributing factor in take-off and landing overrun and veeroff accidents. Therefore the study on them is imperative. For studying the hydroplaning of aircraft tire, a 2D finite element model of aircraft tire is developed by using TYABAS software, and then a 3D patterned tire model is presented. The hydroplaning of aircraft tire is analyzed by generally coupling an Eulerian finite volume method and an explicit Lagrangian finite element method. The hydroplaning speeds are investigated, which is a key factor of hydroplaning. Results indicated that the hydroplaning speed increases with the increment of inflation pressure; the hydroplaning speed decreases with the increment of the footprint aspect ratio.

Abstract: A type of basalt fibers polymer functional composites embedded with ZnO whiskers was prepared. The as-prepared composites exhibited good microwave absorption properties after the dispersion of ZnO whiskers in resin. The dynamic compressive properties of composites were investigated by the split Hopkinson pressure bar (SHPB) system. The macro- and micro-fracture morphology of composites was obtained by the scanning electron microscope (SEM). The experimental results showed that the as-prepared composites have excellent mechanical properties, and the compressive properties could be significantly affected by the strain rates in the in-plane direction, as well as in the normal direction. As the strain rate increased, the higher strength and elastic modulus are obtained. Under the dynamic compressive load in the normal direction, the main failure mode of composites is pure compression. On the other hand, longitudinal splitting and delamination of composites could be induced when loaded in the in-plane direction. The micro- interfacial crack, fiber fracture and plastic deformation of resin could be observed from the morphology of fractured composites.

Abstract: In this paper, moxa leaf powder solution microcapsules are firstly prepared by phase separation of ethyl cellulose. The microcapsule granules prepared are spherical; with good dispersibility and diameters of 10-100μm; have good effects in preservation and prolonged-releasing of active compositions in moxa leaf. The controlled-release experiment proves that after immersing in normal saline for 24 hours under constant temperature of 37°C, releasing amount of the microcapsules is less than 80%, thus the active compositions in moxa leaf still exist in the granules.

Abstract: A finite element model of temperature field coupled with electromagnetic field has been established based on induction heating theory including Maxwell’s equations, thermal conductivity differential equation and magnetic vector potential to simulate the induction heating process of barrel of injection molding machine by universal ANSYS software, and to obtain temperature field of the barrel related to time variation. The coupled thermal and electromagnetic field problem taking account of nonlinear materials characteristics related to temperature was discussed. The induction heating process of barrel was analyzed, and the temperature distribution and its variation with time were obtained.

Abstract: Chemical crosslinker polymer gels were synthesized in situ polymerization of monomers in solvents with crosslinkers. Results showed that the solvent content of the polymer gels depended on the types of solvents and polymers as well as the crosslinkers. The adsorption ability to aromatic organic molecules of the polymer gels was measured by treating tryptophan solution containing phenol and pyrene aqueous solution. The aromatic compounds can be removed completely and no further pollution to the original solutions.

Abstract: The performance advantages of the newly full-hydraulic internal circulation two-platen injection molding machine were investigated deeply and comprehensively. The application prospects were also forecasted. Thanks to the use of internal circulation cylinders in the injection molding machine, the hydraulic system is greatly simplified. Mold-moving and mold-locking are actuated by different cylinders respectively which not only balance the force and velocity but obtain excellent mold-locking properties and high molding stability. The injection molding machine was equipped with servomotor which drives quantified pump in order to save energy and lower noise. The newly full-hydraulic internal circulation two-platen injection molding machine will be the next generation injection molding machine.

Abstract: Injection molding visualization is the experimental method of direct observation on the melt filling behavior in the mold cavity. By using developed visualization system, the influence of mold structure design on the injection molding product’s defects, such as jetting and weld were studied in this paper. The forming process of jetting was observed by the visual method, and results show that it is useful to avoid jetting by locating gate correctly. According to the generation of weld line in single gate cavity, an improved measure to adjust the weld locations by adding overflow traps was proposed. The result indicates that the overflow trap is good for adjusting weld location and makes the defects appear in the unimportant points of surface. Another experiment on the forming process of weld line in two-gate cavity with setting different distance parameters were carried out. The result shows that increasing of gates distance may significantly affect the performance of weld line.

Abstract: Atom transfer radical polymerization (ATRP) has been employed for the synthesis of a novel amphiphilic fluorinated triblock copolymer PEG-b-PS-b-PFHEM for anti-fouling coatings. The macroinitiator based on poly(ethylene oxide) monomethyl ether was used to prepare an amphiphilic diblock copolymer PEG-b-PSt-Br, which was then utilized to initiate the ATRP of fluorinated monomer perfluorohexylethyl acrylate (FHEA), resulting in an amphiphilic triblock copolymer. These copolymers were characterized by means of 1H NMR and GPC. The amphiphilic triblock copolymer surface composes of fluorinated and PEGylated blocks, and the fluorinated surface has critical surface energy, while the PEGylated surface is expected to have a relatively low interfacial energy when in contact with water. Microphase-separation of both blocks could take place and result in the reduction of protein adsorption and cell adhesion. The amphiphilic fluoropolymer has the potential application as excellent antifouling coatings and antifouling membranes.