Advanced Materials Research Vols. 87-88

Abstract: Banana fibers received four treatments, namely squeezing, alkali and hydrogen peroxide treatment, washing with water, and drying. Thermoplastic starch composites was prepared with glycerol as the plasticizer, banana fiber as reinforcement and thermoplastic cassava starch as matrix. The banana fiber could increase processing torque highly, while the effects of fiber contents on peak torque at 3min was so obvious. X-ray diffractograms illustrated that with increasing fiber content, cellulose crystallinity at 22.5° gradually got stronger but starch crystallinity at 20° almost didn’t. SEM micrographs showed good dispersion and adhesion between starch and fiber. Studies in the dependence of mechanical properties of reinforced TPS on the contents of fiber that with increasing fiber content from 0 to 20phr, the initial tensile strength was trebled up to 14.46 MPa, while the elongation at break was reduced from 68 to 13%. TG mass loss curves showed that thermal stability of this composites had great improved under 500°C.

Abstract: The buckling deformation of the liner within composite pressure vessel is investigated using acoustic emission (AE) signals. The liner will fail with buckling deformation which is casued by compression stress induced by deformation compatibility beween composite layer and the liner. The experimental results show that these high-amplitude signals higher than 80dB are responsible for the buckling deformation of the liner within composite pressure vessel during unloading process.

Abstract: An expert system of precise injection molding process optimization based on Moldflow software was set up in this paper. Expert system of precise injection molding process optimization based on Moldflow-MPI module consist of optimization of packing curve, analyzer of parallelism and coaxiality, analyzer of process optimization and integrative forecaster of weld line. The system can be used in the process optimization of precise injection molding, the forecast and control of product properties, and the flaw elimination of product molding.

Abstract: In order to prepare a wood-based composite material which, as a type of multifunctional and natural bio-based material, possesses satisfactory mechanical properties, excellent durability (i.e., decay resistance and dimensional stability), and Aenvironmental characteristic, the study presents a new method which is based on the cellular structure of wood by initiating polymerizable monomers for in situ polymerization. Glycidyl methacrylate (GMA) as a multifunctional and polymerizable monomer was chosen, and impregnated into the porous structure of wood. After a thermal-catalyst process, the wood-based composite, PGMA/Wood, was prepared. The structure of this material was analyzed by SEM, FTIR and XRD; and its performance was also determined. The analyzing results show that GMA not only polymerized in the cellular structure in a solid form and amorphous form, which fully and uniformly filled in wood cell lumen, but also sufficiently grafted onto wood cell walls in a chemical level, resulting in tight contact between wood cell walls and resultant polymers (PGMA) without any obvious cracks. The test results of mechanical properties show that the modulus of rupture (MOR), modulus of elasticity (MOE), compression strength, and hardness of PGMA/Wood increased by 82%, 122%, 139%, and 348% over those of untreated wood, respectively. The test results of durability show that the dimensional stability and decay resistance of PGMA/Wood improved 44% and 91% than those of untreated wood, respectively. Such composite could be widely applied in the fields of construction, furniture and traffic.

Abstract: To study the effection of nano-ZnO on thermal oxidative aging and ultraviolet radiation aging of NR, and the mechanisms of thermal oxidation aging and ultraviolet radiation aging of nano ZnO in NR were explained by TG and stress relaxation and ultraviolet analysis. The results revealed that nano-ZnO can improve the anti-thermal oxidation aging and anti-ultraviolet radiation aging of NR, and the protective effect improves with the increase dose of nano-ZnO.

Abstract: Polypyrrole/wool composite fiber was prepared by in situ oxidative polymerization from vapor phase and liquid phase pyrrole at room temperature, by using FeCl3 as catalyst. The effect of deposition technique on the surface morphology, mechanical properties and the electrical stability of fibers were discussed. The result showed that deposition technique has a strong effect and fiber prepared by vapor phase deposition has much fine and small granular structure, lower resistance, better mechanical property and electrical stability.

Abstract: The relationship between the input and output (displacement of adjusting lever and air flow) of adjustable LAVAL nozzle is deduced. In the pneumatic conveying condition, finite element analysis to adjustable LAVAL nozzle is simulated, and its steady-flow effect is proved. Experiments show the adjustable LAVAL nozzle is energy-saving, can improve the quality of conveyed material, and reduce percentage of damage.

Abstract: Poly (urethane-methacrylate) (PUA) plastic sheets were prepared from isophorone diisocyanate(IPDI), different kinds of polyols, and ß-hydroxyethyl methacrylate(HEMA) in the presence of dibutytin dilaurate(DBTL) as catalyst and 2,2-azo-bis-iso-butyro-nitrile(AIBN) as initiator. The properties of PUAs were measured by dynamic mechanical analysis (DMA), water uptake and optical properties testing, and mechanical performance measurements. The effect of kinds of polyols, which own the same molecular weight, on the properties of PUAs was evaluated. The results show the obtained PUAs present the good mechanical properties, low water uptake (below 2.5 %) and high transparence (above 85 %). The diversity of properties suggests that these PUAs can be used in optical polymer applications.

Abstract: The performances of tires which are affected by improving the building way for semisteel radial tire have been researched. The testing results show that there is a great effect on the tire’s uniformity and dynamic balance because the pressing ways of semi-steel radial tire bis two steps with two rollers lamination make the variation of tread size greater. When the lamination process of two steps with two rollers was changed into three steps with three rollers, the tire’s uniformity and the dynamic balance have been improved effectively, which significantly reduces the possibility of the change when the tread size becomes larger during the lamination of tread.

Abstract: Application of SMR / SBR inner tube with the IIR reclaimed rubber were investigated in the paper. The mechanical properties such as strength, hardness and Mooney viscosity of the materials were measured. The results showed that Elongation at break and tear strength decreased a little, while tensile strength,Viscosity, the air tightness and hardness are improved by adding RIIR in SMR/SBR ,which can accelerate the curing speed of the materials under room temperature. The results indicated that RIIR in SMR/SBR formula can meet the requirement of the processing technology of tube compound.