Atmospheric-pressure Air Plasma Treatment of Polyester Fabrics for Inkjet Printing with Pigment Inks

Without any preprocessing,polyester fabric has lower ability to hold on water and inks due to the smooth morphology of polyester fibers. Therefore, patterns directly printed with pigment inks have poor color yields and bleed easily. Pretreatments of polyester fabric were carried out with atmospheric air plasma under different experimental conditions. After plasma treatment the samples were printed with magenta pigment ink. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) analyses indicated that the enhanced color performance was mainly contributed by not only the etching effect but also oxygen-containing polar groups induced onto fiber surfaces through plasma treatment. Thereby the surface modification of polyester fabrics using atmospheric-pressure air plasma offers a potential way to fabric pretreatment for pigment inkjet printing with the advantages of environmental friendly and energy saving over traditional pretreatment methods.

Preparation of Polyimide Fiber/Thermoplastic Resin Composites with Improved Mechanical Properties

As a high-performance material for preparing composite materials, polyimide fibers suffer from many potential drawbacks, including poor bonding with other substrates, which results in composite materials with poor mechanical properties. Therefore, this study proposed a simple and rapid technique for obtaining loose, porous polyimide fiber papers by implementing a wet method using equal amounts of polyimide fiber and polyimide fiber paper as reinforcements, respectively. The polyimide resin-based composite materials were prepared by hand lay-up and hot pressing. The results showed that the paper-based reinforcement exhibited high porosity and the fibers were arranged with a uniform pore size distribution. The tensile properties, bending performance, and interlaminar shear performance of the paper-based composite improved by 130%, 108%, and 34.5%, respectively, compared to those of the fiberbased counterpart. The factors affecting the mechanical properties of the composites were analyzed based on the fiber length, fiber beating or lack thereof, and the basis weight of the paper. The increased uniformity of the polyimide fiber paper changed the ordering of the fibers and resolved drawbacks such as difficult dispersion, uneven pore size distribution, and poor mechanical properties related to single fibers in the resin-based composite material.

Study on Permeability of 2.5D Woven Reinforcement Materials with Fractal Theory

Permeability is one of the key issues in the design of molds and in the molding process for composite manufacture.As a disordered fibrous assembly,2.5-dimension(2.5D)woven reinforcement materials have complex structure.It poses a challenge to the study of pore structure and the establishment of the theoretical permeability model.Toward addressing this problem,a powerful tool called fractal theory emerged.According to the analysis of 2.5D woven reinforcement material structure using fractal theory,it is found that the structure has an obvious fractal character.Therefore,a permeability fractal model of 2.5D woven reinforcement material was established by combining the Hagen-Poiseulle equation with Darcy law according to the capillary vessel fractal model in this paper.The permeability was expressed as a function of the fractal dimension and microstructure parameter of the porous media in this model.The theoretical model is verified by experimental tests and the measurement data are in good agreement with the results obtained from the fractal model.

The Structural Characteristics of Side-Opening Costumes during the Republic Period of China

The structural characteristics of Chinese side-opening costumes during the Republic Period of China were investigated.By measuring and recovering the physical structures of side-opening costume objects from the Folk Costumes Biography Museum of Jiangnan University,three structural characteristics were analyzed.These structural characteristics show that most of the side-opening costumes during the Republic Period of China remain traditional Chinese costume structures.The general structural characteristics of side-opening costumes are concluded and the structural cutting methods can inspire current designs as well as provide useful references for contemporary fashion designers.

Liquefaction of Rice Straw with Ethylene Carbonate

In this study,rice straw(RS) was liquefied by ethylene carbonate(EC) using H_2SO_4 as a catalyst.The effects of various process conditions on the liquefaction characteristics were investigated by FT-IR and residue content analysis.The results show that cellulose and lignin are degraded during the liquefaction process and large amounts of groups are generated.In addition,it is difficult to effectively liquefy RS by using EC alone as the liquefying agent without other additives.Compared to water addition on liquefaction,the residue content can be significantly reduced up to 30% by adding H_2O_2.It has also been proved that the liquor ratio(RS/EC,w/v) of 1∶5 with H_2O_2 as an additive at 145℃ for liquefaction time of 60 min in the presence of H_2SO_4 can accelerate the liquefaction process and high liquefaction yield can be obtained.

Influence of dihydric alcohols on color performance of reactive dye inks

The effect of five dihydric alcohols on the fixation rate and K/S value of reactive dyes on cotton fabrics was investigated.Results show that the more primary hydroxyl groups are contained in the isomeric dihydric alcohols,the greater activity of reacting with the reactive dye.Longer carbon chain also increases the reactivity of dihydric alcohols with reactive dyes.This study provides a theoretical basis for the selection of suitable dihydric alcohols in preparation reactive dye inkjet printing ink.