Hong Yan Wu

Crystallization and Mechanical Properties of Nano ZnO/PP/PLA Composite Filaments

In the present work, the effect of plasma treated ZnO nanoparticle on crystallization behavior and properties of polypropylene（PP）/ polylactic acid （PLA）composites filaments has been intensively researched. Our results show that, although the interfacial interaction between PP/PLA and nano ZnO is very weak, addition of nano ZnO and the proportional relations of PP/PLA in composites induced the increase of percent crystallinity. Tensile results showed that nano ZnO /PP/PLA nanocomposites filaments were strain rate sensitive materials and the activation volumes of the nano ZnO /PP/PLA nanocomposite filaments by following Eyring’s equation could be evaluated.

The Microstructural Deformation of the Montmorillonite Particles/Polypropylene/Polylactic Acid Nanocomposite Filaments Infused with Plasma Treated Montmorillonite

The purpose of the present work is to investigate the microstructural deformation of the montmorillonite (MMT) particles/polypropylene (PP)/polylactic acid (PLA) nanocomposite filaments infused with plasma treated MMT. The activation volumes of the MMT/PP/PLA nanocomposite filaments ranging from 31.4572 to 151.2100 (nm)3 estimated by the Eyring’s equation quantitatively revealed that the plasma treated MMT acted as obstacles to dislocation motion during microstructural plastic deformation mechanisms. DSC analysis showed marked increases in glass transition temperature (Tg), indicating the plasma treated MMT could effectively help resist the free crankshaft movement of the macromolecular chain in the nanocomposite filaments. In addition, the MMT/PP/PLA nanocomposite filaments developed intercalated structures which had been examined by SEM.

The Strain Rate Sensitivity of Plasma Treated Nano TiOx Particles/PP/PLA Nano-Composites Filaments

In the current study the role of plasma treated nano titanium dioxide particles and strain rate on the tensile properties of plasma treated nano TiO2 particles/PP/PLA nano-composites filaments (PTNTOPPCF) was studied. The experiments included tensile tests and differential scanning calorimetry (DSC). The addition of the plasma treated nano titanium dioxide particles into PP/PLA caused a change in Youngs modulus and yield stress of the composites. Strain rate sensitivity of the PTNTOPPCF changed as plasma with and without oxygen treated nano titanium dioxide particles was added to it with different percentage of weight. It was increased with more PLA, MAH, and higher flow rate of oxygen. Activation volumes ranged in 4−40(nm)3 for true nanocrystalline material estimated by the Eyring equation, which were changed un-monotonically with oxygen plasma treatment.

Optimization Fabrication of Plasma Treated Nano-Titanium Dioxide Particles/PP/PLA Composites Filaments Using Melt Spinning

The Melt spinning technique of Nano-titanium dioxide particles/PP/PLA composites filaments fabricated by plasma treated Nano-titanium dioxide particles studied in the present investigation. The experimental results showed that the physical and mechanical properties of Nano-titanium dioxide particles /PP/PLA composites filaments depended on the following factors of the percentage of Nano-titanium dioxide particles, the percentage of maleic anhydride (MAH), plasma treatment parameters: flow rate of helium gas, output power, sample treatment or stationary time and flow rate of oxygen gas. Among it the flow rate of oxygen gas had the significant influence on the filament properties of tensile modulus, the yield strength and the melting temperature. Stepwise multiple regressions orthogonal design method of system optimization used to determine the percent of contribution of each factor. It found that the three indicators were different by these analyses. The experimental results indicated that the optimized conditions by stepwise multiple regressions were better than that by traditional analysis.

Nano Effects of Helium Plasma Treatment Nano SiO2 Coating Kevlar Filaments

The strain rate sensitivity of helium plasma treated Nano Silicon Dioxide particles sol-gel coating Kevlar filaments (HPTNSDPKEVLAR) and concurrent micro-structural evolution. The results of SEM observation and contact angle analysis showed that the treated Kevlar filament had a rougher surface and lower contact angles than the untreated one. According to the FTIR results, the change of wettability was attributable to the amount of polar functional groups on the fiber surface introduced by the treatments. Moreover, the changes of physico-mechanical properties by HPTNSDPKEVLAR were analyzed by using tensile test at different strain rates range from ranging from 0.01 s-1 to 0.6 s-1. It was found that the materials were strain rate sensitive, and both the tensile strength and failure strain increased with increasing strain rate. The dependence of yield stress by HPTNSDPKEVLAR with strain rate followed Eyring’s equation, and may be characterized by implying the similarity in the onset of plastic deformation.

Effect of TiO2 Nanoparticle on Thermal and Tensile Behavior of Polypropylene/ Polylactic Acid Composite

The role of both nano-sized of plasma treated Nano Titanium Dioxide particles and strain rate on the tensile properties of plasma treated Nano Titanium Dioxide particles/PP/PLA nano-composites filaments (PTNTOPPCF) was studied. Filaments tensile samples of PTNTOPPCF were prepared by a twin screw mixer- twin screw extruder with a particle content of 0.3~1%. The influence of surface treatment of the particles, with and without low-temperature oxygen plasma treatment, on the physico-mechanical properties was studied. The tensile tests were carried out, differential scanning calorimetry (DSC) and SEM were used in this investigation. Tensile tests were done at different strain rates. The addition of plasma treated Nano Titanium Dioxide particles to PP/PLA caused a change in Youngs modulus and yield stress of its composites. The experimental results also showed that the strain-rate sensitivity of PTNTOPPCF changed as plasma with and without oxygen treated Nano Titanium Dioxide particles was added to it with different o.w.f.. We found that the models lead to estimates of activation volumes in the range 4−40nm3 for truly nanocrystalline material. Activation volumes were found to changing un-monotonically with oxygen plasma treatment. The findings were found to be in accord with available experimental evidence in both a quantitative and qualitative manner. Deficiencies in the available experimental evidence were noted, specifically in the context of explaining some of the difficulties in comparing theoretical predictions to experimental observation.

Surface Characterization of Oxygen Plasma Treated Nano-SiO2 Sol-Gel Coating UHMWPE Filaments

UHMWPE filaments have a low surface free energy and therefore often require a modification of their surface properties before any use. Atmospheric pressure plasmas treatment is a convenient and environmentally friendly way to obtain these modifications by introducing new chemical groups at the surface without affecting the bulk properties. This paper studies the influence of nano-SiO2 sol-gel coating pretreatment on atmospheric pressure plasma jet (APPJ) treatment of ultrahigh molecular weight polyethylene (UHMWPE) fibers when a mixture of 100% helium and 1% oxygen used as the treatment gas. The surface properties of the plasma-treated UHMWPE filaments are characterized using contact angle measurements and ATR-FTIR spectroscopy. The UHMWPE filaments show a remarkable increase in surface free energy after plasma treatment. ATR-FTIR spectroscopy of the plasma-treated UHMWPE filaments reveals that plasma treatment introduces oxygen-containing functionalities on the UHMWPE filaments surface leading to the increased surface free energy.

Fabrication of Plasma Treated Nano Zinc Oxide/PP/PLA Composites Filaments Using Melt Spinning

The Melt spinning technique of Nano Zinc Oxide/PP/PLA composites filaments fabricated by plasma treated Nano Zinc Oxide（NZOP） was studied in the present investigation. The experimental results showed that the physical and mechanical properties of Nano Zinc Oxide/PP/PLA composites filaments depended on the following factors of the percentage of NZOP, the percentage of maleic anhydride (MAH), the plasma treatment parameters, helium gas flow rate, output power, sample treatment or stationary time and oxygen gas flow rate. Among them the oxygen gas flow rate had the significant influence on the filament properties of tensile modulus, the yield strength, the melting temperature and the crystallization temperature. Stepwise multiple regressions orthogonal design method of system optimization was used to determine the percent of contribution of each factor. It was found that the four indicators were different by these analyses. The experimental results indicated that the optimized conditions by stepwise multiple regressions were better than that by traditional analysis.

Effects of Oxygen Plasma Treated Carbon Nanotube Coating Basalt Filaments

The strain rate sensitivity of Oxygen plasma treated carbon nanotube sol-gel coating Basalt and concurrent microstructural evolution investigated. Both the materials are strain rate sensitive and the change in index parameter of strain rate sensitivity with strain reflects the change in micromechanisms of deformation and mode of fracture. From the SEM micrographs, an increase in surface roughness can observed and the degree of fibrillation decreased after helium and oxygen plasma treatment. Contact angle analysis showed the treated Basalt filament had lower contact angles than the untreated one. Based on FTIR results, the change of wettability and surface energy is attributable to polar groups on the fiber surface introduced by the treatments. Deformation processes in the Oxygen plasma treated carbon nano tube sol-gel coating Basalt involved craze-tearing and brittle mode of fracture, while plasma treated carbon nano tube in nano-composites filaments predominantly characterized by wedge, ridge tearing, fibrillation and brittle fracture. Depend yield stress of the Oxygen plasma treated carbon nanotube sol-gel coating Basalt with strain rate follows Eyring’s equation.

Nano Effects of Oxygen-plasma Treatment nano-SiO2 Sol-gel Coating T-300 Carbon Fiber

The purpose of the present work was to investigate the effects of oxygen-plasma treatment on tensile deformation of nano-SiO2 sol-gel coating T-300 carbon fiber (HONS3C) were studied and a new concept for the nano-structural interphase between fiber surface and nano-coating provided in the paper. The tensile test results showed that besides the enhanced ductility of T-300 carbon fibers by nano-SiO2 sol-gel coating the T-300 carbon fibers treated by oxygen-plasma, the activation volumes of T-300 carbon fibers untreated and treated with oxygen-plasma ranging from 681.9628 to 32342(nm)3 by following Eyring’s equation were important descriptors for the properties of the nano-structural interphase between fiber surface and nano-coating, From the results of SEM and FTIR, it was observed that the uniform dispersion of the nano-SiO2 coating of the T-300 carbon fibers treated by oxygen-plasma not only formed a protective layer to cover the fibers, but also introduced the activated functional groups on the fiber surfaces.