Materials Science Forum Vol. 1032

Abstract: Novel visible light-induced carbon nitride intercalation compound (CNIC) with iron oxide composite photocatalyst with different content of iron oxide were synthesized through simple mixing and heat treatment. The composite photocatalyst was characterized by Fourier transform infrared (FT-IR) spectroscopy and BET surface area measurements. The photocatalytic oxidation ability of the novel composite photocatalyst was evaluated using methyl range (MO) as a target pollutant. The experimental results showed the composites with a content of iron oxide exhibited the higher photocatalytic activity than either single-phase iron oxide or CNIC under visible-light irradiation. The as-prepared composite photocatalyst exhibits an improved photocatalytic activity due to enhancement of photo-generated electron–hole separations at the interface.

Abstract: When the flexible deformation of composite materials directional pipe which influences the movement of rocket projectile is considered, the visual prototype is a good approach that calculates the course of rocket projectile launch. In this thesis, the mechanical model of bearing load of composite materials directional pipe is established, and the theory and arithmetic of calculation are expatiated. After the simulation model is established and simulation calculation is done, not only the needed data and results are gained, but also the movement principles of rocket projectile in directional pipe and the dynamic mechanical capabilities of FRP directional pipe are held.

Abstract: The accuracy of the rubber constitutive model characterizing experiment data has a crucial influence on the mechanical analysis of rubber structures. In this paper, a new improved hyperelastic constitutive model is proposed, and the model is derived into the stress-strain forms of uniaxial tension, equibiaxial tension and pure shear. Based on the experimental data of filled rubber, the material parameters of each deformation state are obtained by using the newly proposed rubber hyperelastic constitutive model, and the uniaxial tensile (UT), Equibiaxial tension (ET) and Pure shear (PS) specimens are simulated and calculated in the finite element software. the stress state of each finite element specimen is analyzed and the obtained simulation data are compared with the experimental data. It is found that the new model can accurately characterize the hyperelastic mechanical properties of the experimental specimens in different deformation states. At the same time, the reasons for the deviation from the experimental data in the process of plane tensile simulation are analyzed and explained comprehensively. The reliability and accuracy of the classical rubber constitutive relations of polynomial models and eight-chain model are studied. the results show that different hyperelastic models have different ability to describe the hyperelastic behavior in different deformation states. the hyperelastic constitutive model proposed in this paper can be easily embedded into finite element software and has the advantages of accurate results, few material parameters and simple testing.

Abstract: Good quality of plastic packaging waste has the potential to be recycled, as it can be used as raw material for the next packaging products. Recycling is preeminent due to the grave necessity of decreasing plastic production rate, especially for packaging industries which are known to use more plastic compared to other sectors. Material value conservation is a new paradigm which can be implemented through a new category of design for recycling in order to avoid value degradation. Implementations of this paradigm has produced better quality processed plastic waste with higher selling price. Applied with this paradigm, recycled plastic pellets can be a viable alternative as raw material based on its mechanical properties, even after the 8th stage of recycling. This study aims to reveal the effect of repetitive recycling on the optical properties of polypropylene with implementation of material value conservation paradigm, to strengthen previous evidence of the implementation of the material value conservation paradigm on plastic packaging whether repetitive recycling plastic packaging can be a viable alternative as raw material based on its optical properties. Optical properties observed in this research were based on the American Society for Testing and Materials (ASTM) standards, which are consisted of colour (ASTM D2244), gloss (ASTM D2457) and transparency (ASTM D1746). The result of this study indicated that even after the 8th stage of recycling, plastic pellet of polypropylene still can be a viable alternative as raw material based on its optical properties, with more attention on transparency property.

Abstract: Polymer materials play an important role in today's social development, and become important materials in industry, agriculture, national defense and other fields. With the further development of modern engineering material technology, polymer materials, together with information technology and biotechnology, promote the progress and development of society. The performance and quality of modified polymer materials have also entered the research field of vision of various industries and become the focus of exploration and analysis. The following is the research on the fracture behavior of modified polymer materials with the help of digital image correlation method. The purpose of this paper is to clarify the basic fracture work, shaping work and other fracture work parameters of various modified polymer materials, and grasp the root cause of fracture work parameters of modified polymer materials, so as to clarify the modification processing parameter means of these polymer materials.

Abstract: The coaxial electrospun fibers with large specific surface area, high porosity and core-shell structure have been great applied in biomedical field, especially as drug delivery carriers. In this paper, PLGA(polylactic acid/glycolic acid copolymer) was used as the core and the mixture of PLGA and gelatin was used as the shell. PLGA/gelatin fiber was prepared by coaxial electrospinning technology. The effects of different parameters on the surface morphology and the diameter of fibers were investigated.

Abstract: The compound enzymolysis was studied to improve cloudy apple juice yield. Pectinase, cellulase and xylanase with high decomposition activity for cloudy apple juice were selected for compound enzymolysis. Response surface methodology was used to analyze the optimal additive amount. Results showed that, the effect of interaction between cellulase and xylanase on juice yield was extremely significant (P < 0.01). The optimal condition of complex enzymatic hydrolysis was: pectinase 0.16%, cellulase 0.57% and xylanase 0.12%. The better condition of compound enzymolysis was 45 °C for 60 min. The juice yield of cloudy apple juice significantly improved after optimized enzymolysis, which reached up to 83%.

Abstract: In the paper, a novel perovskite microcrystalline with a capsule-free cavity box structure was creatively prepared through solvent thermal reaction, and the composition and structure of CH₃NH₃PbI₃ perovskite microcrystalline were further characterized by scanning electron microscope (SEM) and energy dispersive X-ray (EDX) element mapping. The SEM results show that the grain size of the prepared CH₃NH₃PbI₃ perovskite microcrystalline is more than 100 μm. Furthermore, X-ray diffraction (XRD) analysis was used to characterize the material decomposition of perovskite microcrystals before and after 150 d of air aging. The XRD results indicate the prepared perovskite microcrystalline could be stably preserved in the air for 150 d without degradation. Our method provides technical guidance for further enriching the morphology of CH₃NH₃PbI₃ perovskite microcrystalline.

Abstract: The structure of basic lanthanum orotate (LaOr) were characterized by elemental analysis and infrared spectroscopy. The thermal stability of polyvinyl chloride (PVC) was further studied by Congo red method, oven discoloration method and thermogravimetric analysis. The results showed that LaOr could prolong the oven discoloration time of PVC, and the color was not completely blackened until 120 min. It has a good synergetic effect with dibenzoyl methane (DBM), and the best effect is achieved when LaOr/DBM ratio is 1.8/1.2. The thermal decomposition kinetics experiment showed that adding DBM can effectively improve the activation energy of PVC/LaOr. The stabilization mechanism of PVC was studied by absorbing HCl method and infrared spectroscopy. The results showed that LaOr could not only replace the unstable chlorine atoms on PVC, but also promote the long-term thermal stability of PVC by absorbing HCl.