Xin Ying Lv

Effect of Different Compatibilizing Agents on the Compatibility of Lignin/LDPE Composites

Lignin has been blended with low density polyethylene (LDPE). Maleic anhydride grafted high density polyethylene (HDPE-g-MAH) and Maleic anhydride grafted polypropylene (PP-g-MAH) have been added as compatibilizing agent. The weight ratio of LDPE, ligin and HDPE-a-MAH were 75:25:7.5, 75:25:10 and 75:25:12.5; the weight ratio of LDPE, ligin and PP-a-MAH were 75:25:5, 75:25:7.5 and 75:25:10 respectively. The mechanical properties of the blends were investigated according to Chinese standard GB/1447-2005 and compared with those of lignin/LDPE composites without compatibilizing agent. Scanning electron microscopy (SEM) was used to investigate the dispersion of the lignin and PE and the compatibilizing mechanism was analyzed. The results reveal that addition of compatibilizing agent increased the interfacial bonding strength of the composites, improved the mechanical properties and obtained the better dispersion of the lignin and LDPE with HDPE-g-MAH as compatibilizing agent.

Mechanical Study and Microscopic Characterization of Lignin/PE Composites

The lignin/PE composites with different compatibilizing agents were extruded and the tensile properties have been tested. The weight ratio of PE, ligin and PE-a-MAH were 7.5%, 10%and 12.5wt%; the weight ratio of PE, ligin and PP-a-MAH were 5%, 7.5% and 10wt% respectively. Scanning Electron Microscopic (SEM) was used to characterize the morphology of the composites. The tensile strengths of lignin/PE composites with PE-g-MAH were higher than that one with PP-g-MAH. Both of them were higher than that one without any compatibilizing agent. And PE-g-MAH was the better compatibilizing agent confirmed by the mechanical tests and SEM results.

Impacts of Molding Pressure on Performances of Kraft Fiber Reinforced Unsaturated Polyester Composites

Novel Kraft fiber reinforced unsaturated polyester (UPE) composites were prepared at various molding pressures in order to investigate the effects of molding pressure on resin content, the mechanical properties and creep resistance. The results indicated that the novel composites had much higher mechanical properties and better creep resistances than traditional wood plastic composites because of the applications of strong Kraft fibers as reinforcement and thermosetting UPE as matrix. Molding pressure had various effects on the many properties of composites. With molding pressure increased from 6MPa to 25MPa, the mechanical properties and creep resistances increased gradually until about 20MPa and then decreased, which were attributed to the different interface adhesions between UPE resin and Kraft fibers at various molding pressures as evidenced by DMA analysis. Benefited from the use of low-viscosity UPE resin, the resin content of Kraft fiber reinforced UPE composites could reduce to 28.3% while strength and creep resistance were still much better than that of the thermoplastic wood-plastic composite (WPC) with 40% polymer matrix.

Effects of Initiator Level on Performances of Kraft Fiber Reinforced Unsaturated Polyester Composites

Relative lower strength and poor creep resistance of wood-plastic composites (WPC) restrain their wider applications in building and automotive. A novel wood-polymer composite was prepared using Kraft fiber and unsaturated polyester (UPE), which had much higher strength and better creep resistances than that of traditional thermoplastic WPC. Effects of initiator on the mechanical properties and creep resistance of this novel composite were investigated by tensile evaluation, DMA, SEM and short-term creep test. Test results indicated that initiator level had important effects on mechanical properties and viscoelastic behaviors because of various crosslinking densities of UPE matrix and interface adhesions between Kraft fiber and UPE resin under various initiator levels. With initiator level increased from 0.3% to 1%, the tensile strength and interface adhesion increased at the beginning and then decreased, while the instantaneous strain and maximum strain in the creep test decreased gradually. As for hot molding at 125°C, initiator level shall be less more than 1% and be preferable to 0.5%-0.7%.

Effect Of PP-G-MAH on the Compatibility of Lignin/LDPE Composites

Lignin have been blended with low density polyethylene (LDPE). Maleic anhydride grafted polypropylene (PP-g-MAH) has been added as compatibilizing agent. The weight ratio of LDPE, ligin and PP-a-MAH were 75:25:5, 75:25:7.5 and 75:25:10, respectively. The mechanical properties of the blends were investigated according to Chinese standard GB/1447-2005 and compared with those of lignin/LDPE composites without compatibilizing agent. Scanning electron microscopy (SEM) was used to investigate the dispersion of the lignin and LDPE and the compatibilizing mechanism was analyzed. The results reveal that addition of compatibilizing agent increased the interfacial bonding strength of the composites, improved the mechanical properties and obtained the better dispersion of the lignin and LDPE.

Compatibility of Lignin/LDPE Composites Modified with HDPE-G-MAH

Lignin have been blended with low density polyethylene (LDPE). Maleic anhydride grafted high density polyethylene (HDPE-g-MAH) has been added as compatibilizing agent. The weight ratio of LDPE, ligin and HDPE-a-MAH were 75:25:7.5, 75:25:10 and 75:25:12.5, respectively. The mechanical properties of the blends were investigated according to Chinese standard GB/1447-2005 and compared with those of lignin/LDPE composites without compatibilizing agent. Scanning electron microscopy (SEM) was used to investigate the dispersion of the lignin and LDPE and the compatibilizing mechanism was analyzed. The results reveal that addition of compatibilizing agent increased the interfacial bonding strength of the composites, improved the mechanical properties and obtained the better dispersion of the lignin and LDPE.

Further Analysis and Multiple View of Assist Developed Platform

SSH framework software is a system implemented by struts or struts2, spring, hibernate, It is used to implementing java web application system. This article study concept of struts2springhibernate and character of SSH Framework, design and implement an assist developed platform based on SSH framework, It may provide efficient, simple, stable support for SSH framework system.

Preparation of Particleboard Made from Wheat Straw with Low-Formaldehyde-Emission Composite Adhesive

This research attempted to prepare the E0 type wheat straw particleboards with low emission formaldehyde composite adhesive. The composite adhesive combined UF resin and blocked polyisocyanate with low deblocked temperature was synthesized with sodium bisulphate as blocking agent. The effects of different blocking agents, mol ratio, reaction temperature and time on block reaction were studied. The influence of mixed ratio of composite adhesive on the performance of wheat straw particleboard was investigated.

Effect of Coupling Agent on Bonding Properties of Wood/Polyethylene Composites

The surface of wood/polyethylene (PE) composites were treated by mechanical polishing treatment and coating treatment, and the structure of surface for wood/PE composites before and after treatment was characterized by fourier transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) in this paper. Combined with bonding strength test, the effect of coupling agent KH-560 (2,3-epoxypropoxypropyltrimethoxysilicane) on bonding properties of wood/PE composites was also investigated. The results showed that, the -OH, -C-O- and C=O functional groups were appeared on the treated surface and the surface roughness increased after mechanical polishing treatment and coating treatment, which increased the shear bonding strength for the treated sample significantly. And the coupling agent KH-560 can increase the bonding strength for the composite more significantly due to the co-reaction of epoxy groups which introduced by coupling agent with epoxy resin adhesives.

Effect of Thermal-Oxidative Aging on the Mechanical Properties of Carbon Fiber Reinforced Bis-Maleimide Composites

Bis-maleimide (BMI) resins are widely applied in carbon fiber reinforced polymer composites in aerospace fields, for their excellent thermal and mechanical properties. The effects of thermo-oxidative aging on mechanical properties of carbon fiber reinforced BMI composites were investigated by SEM with the combination of flexural strength test and inter-laminar shear strength (ILSS) test. The results indicated that the thermal-oxidative aging had some effects on mechanical properties of carbon fiber/BMI composites; however the testing temperature or service temperature had much more effects than aging time. With aging time increased, the flexural strength at 150 oC and the ILSS at 25 oC slightly increased, while the ILSS at 150 oC decreased gradually. Both test results of mechanical properties and fracture models of damaged flexural specimens by SEM indicated that the matrix resin in the composites showed some viscoelastic behaviors that resulted in the remarkable dependence of mechanical properties of the composites on temperature. Therefore, the carbon fiber reinforced BMI composites had lower flexural strength and ILSS at 150 oC than that at 25 oC.