Yi Ping Qiu

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.

Preparation and Properties of PP/PLA /Multiwall Carbon Nanotube Composites Filaments Obtained by Melt Compounding

The present paper studied the thermal and mechanical properties of atmospheric pressure plasma jet (APPJ) treated multiwall carbon nanotubes/polypropylene/polylactic acid nanocomposite filaments. The experiments included tensile tests, differential scanning calorimeter (DSC), Scanning electron microscopy (SEM) experiments. DSC studies showed that there were a distinct shift in Tg and a relatively moderate change in Tm for different systems. The activation volumes of CNTs/PP/PLA nanocomposite filaments have been calculated to describe strain rate sensitive behavior of CNTs/PP/PLA nanocomposite filaments by following Eyring’s equation based on the tensile test results.

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.

Multi-Scale Polyimide/Carbon Fibers Hybrid Filters for Hot Gas Filtration

Increasing air pollution caused mainly by exhaust emission has become a serious concern for public health. In order to efficiently control the exhaust emission from the origin, hot gas filtration is required in many industries, such as thermal power regeneration, metal refining/recycling, and biomass/coal gasification. This study aimed to develop a hybrid filter composed with ultrafine fibrous polyimide (PI) filtration layers and carbon woven fabric supporting layers for hot gas filtration. Uniform PI ultrafine fibers around 200 nm with small pores about 2.2 μm were electrospun on carbon fabrics supporting layers to serve as the filtration layer. During filtration test, NaCl aerosols (0.3 mm), which mimicked PM 2.5 particles were accumulated on the top of filtration layer and formed dust cake, but limited aerosols were observed on the carbon fabric supporting layers. It was proved that PI fiber mats played the key role in filtration. The filtration efficiency could be maintained above 95% after 9 min and reached 99.4 %. This research proved that the multi-scale polyimide/carbon fibers hybrid filters possessed the potential to serve as filtration media in bag filters for hot gas filtration.

A Novel Testing Method of the Wet Wearing Comfortability of Fabrics

It has long been a problem how to objectively evaluate the wet wearing comfortability of fabrics. In this paper a novel testing method was proposed, and an instrument was designed and made. During the testing process, the fabric specimen first got saturated by “sweat” and adhered on the “skin”, and then it was separated at due rate from the skin and the in time adhesion force-displacement curve was drawn simultaneously. When the fabric was totally separated from the skin, the maximum adhesion force and adhesion work were measured such as to objectively evaluate the adhesion properties of the fabric specimen. Six different kinds of fabrics were selected and tested. The results show that certain kind of fabric performs characteristic adhesion force-displacement curve, which should be explained through fabric materials and structures. Hence this method is effective in objectively reflecting the wet wearing comfortability of fabrics.

Uniformity and Penetration of Surface Modification Effects of Atmospheric Pressure Plasma Jet into Textile Materials

The objective of this study was to investigate the uniformity and penetration of surface modification into textile materials including fiber, yarn and fabric treated by atmospheric pressure plasma jet (APPJ). Exposure to helium/oxygen plasma at atmospheric pressure made improvement in the wettability, dyeability, adhesion of single fiber, yarn and woven fabric. The results showed that such a plasma jet was possible and effective in penetration of surface modification into textile structure. It can treat the whole surfaces of a single fiber, yarn filament in the treated parallel filament tow uniformly. For porous fabrics, rapid and efficient treatment on both sides of the treated samples was found to be ensured. And the degree and depth of penetration depended on the penetration of active species in plasma jet, which was affected by plasma parameters and materials structure. The former included treatment time, power, gas temperature, jet-to-substrate distance. The latter included number of twisting and fabric pore size. These findings would have important effects on industrialization of textiles treated by atmospheric pressure plasma jet.

Comparison of Plasma-Aided Desizing with Conventional Desizing of Polyacrylate on PET Fabrics

The influence of He/O2 atmospheric pressure plasma jet (APPJ) treatment on subsequent wet desizing of polyarylate on PET fabrics was studied in present paper. Atomic force microscopy (AFM) and Scanning electron microscopy (SEM) showed an increased surface roughness after the plasma treatment. SEM also showed that the fiber surfaces were as clean as unsized fibers after 35 s treatment followed by NaHCO3 desizing. X-ray photoelectron spectroscopy (XPS) analysis indicated that oxygen-based functional groups increased for the plasma treated polyacrylate sized fabrics. Compared to conventional wet desizing, plasma treatment could significantly reduce desizing time.