Enhancing Anti-Static Performance of Fibers by Construction of the Hybrid Conductive Network Structure on the Fiber Surface

The hybrid antistatic agent SCNTs/OAA composed of sulfonated carbon nanotubes (SCNTs) and organic antistatic agent (OAA) was treated on the fiber surface to construct the hybrid conductive layer. Among them, SCNTs were synthesized through a simple method, and their chemical structure and morphology were characterized. SCNTs had good dispersibility due to the presence of sulfonic acid groups, which made SCNTs uniformly dispersed on the fiber surface. The SCNTs/OAA-treated fiber was hardly affected by relative humidity, because SCNTs form a continuous and uniform physical conductive network on the fiber surface. When the addition amount of SCNTs/OAA was 0.5~2 wt%, the fiber had excellent antistatic ability. Under the synergistic effect of SCNTs and OAA, the resistivity of SCNTs/OAA-treated fiber was almost not affected by fiber stretching

J. Eur. Ceram. Soc.

C/C-SiC composites were prepared by molten infiltration of silicon powders, using porous C/C composites as frameworks. The porosities of the C/C-SiC composites were about 0.89-2.8 vol%, which is denser than traditional C/C composites. The ablation properties were tested using an oxyacetylene torch. Three annular regions were present on the ablation surface. With increasing pyrocarbon fraction, a white ceramic oxide layer formed from the boundary to the center of the surface. The ablation experimental results also showed that the linear and mass ablation rates of the composites decreased with increasing carbon fraction. Linear SiO2 whiskers of diameter 800 am and length approximately 3 mu m were formed near the boundaries of the ablation surfaces of the C/C-SiC composites produced with low-porosity C/C frameworks. The ablation mechanism of the C/C-SiC composites is discussed, based on a heterogeneous ablation reaction model and a supersaturation assumption. (C) 2013 Elsevier Ltd. All rights reserved.C/C-SiC composites were prepared by molten infiltration of silicon powders, using porous C/C composites as frameworks. The porosities of the C/C-SiC composites were about 0.89-2.8 vol%, which is denser than traditional C/C composites. The ablation properties were tested using an oxyacetylene torch. Three annular regions were present on the ablation surface. With increasing pyrocarbon fraction, a white ceramic oxide layer formed from the boundary to the center of the surface. The ablation experimental results also showed that the linear and mass ablation rates of the composites decreased with increasing carbon fraction. Linear SiO2 whiskers of diameter 800 am and length approximately 3 mu m were formed near the boundaries of the ablation surfaces of the C/C-SiC composites produced with low-porosity C/C frameworks. The ablation mechanism of the C/C-SiC composites is discussed, based on a heterogeneous ablation reaction model and a supersaturation assumption. (C) 2013 Elsevier Ltd. All rights reserved

The Modification of a Tetrafunctional Epoxy and Its Curing Reaction

Recent experimental results showed that the Tg of cured resin scarcely decreased and the impact strength of resins increased by over 50% when a tetrafunctional epoxy named N,N,N\u27,N\u27-tetraglycidyl-4,4\u27-diaminodiphenyl ether (TGDDE) was introduced to an appropriate flexible chain from a dimer fatty acid (DFA). In order to understand the reason for this phenomenon, the modification and the chemical structure of the prepolymer together with the curing reaction and the viscoelasticity of the cured resins were studied in detail in the present work. The results indicated that the modification would help the prepolymer improve its molecular mobility. As a result, the resins could be further cured, resulting in the cross-linking density increasing. This is because the curing efficiency was increased, but the tetrafunctional epoxy was not cured completely due to its large steric hindrance. Moreover, the flexibility of some parts of the networks was improved, which was beneficial for the toughness of the cured resins. Therefore, the toughness of the tetrafunctional resin was improved with little influence on the thermal properties when the epoxies were modified with an appropriate content of DFA

Supplemental Material - Wear failure mechanism analysis of self-lubricating fabric composites at high temperature

Supplemental Material for Wear failure mechanism analysis of self-lubricating fabric composites at high temperature by Mingming Yu, Min Zhang, Lin Fang, Musu Ren, Lei Liang, Wang Xie and Pibo Ma in Journal of Industrial Textiles</p