Electrospun magnetic fibrillar polyarylene ether nitriles nanocomposites reinforced with Fe‐phthalocyanine/Fe3O4 hybrid microspheres

The electrospinning method has been employed to fabricate ultrafine nanofibers of high‐performance polyarylene ether nitriles (PEN) and PEN/Fe‐phthalocyanine/Fe₃O₄ nanocomposite fibers for the first time. Through optimizing the operational conditions, such as polymer concentration, applied electric voltage, federate, and distance between needle tip and collector, bead‐free and uniform fibers with smooth surfaces and certain diameters were obtained. The morphology of the PEN nanofibers is correlated to the corresponding rheological behaviors of the polymer solutions. The nanocomposite fibers showed a beads‐in‐string structures without agglomeration after introducing the Fe‐phthalocyanine/Fe₃O₄ hybrid microspheres in the polymer fibers. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) reveal an enhanced thermal stability of the nanocomposite fibers after introducing the hybrids. The glass transition temperature (T_g) of the nanocomposite fibers increases by 10°C with 30 wt % hybrid microspheres, compared with those of the pure PEN fibers. The magnetic properties of the PEN/Fe‐phthalocyanine/Fe₃O₄ nanocomposite fibers are different from those of the hybrid microspheres. The hybrid microspheres in the composite nanofibers become magnetically harder with a much larger coercivity than that of the fillers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

工程塑料PEN在包装上的研究及应用进展

介绍新型工程塑料ＰＥＮ及其合金的性能和生产状况,重点介绍ＰＥＮ在包装业的研究及应用进展。     

2,6-二甲基萘技术现状及应用

概述了2,6－二甲基萘的技术现状,对4种合成方法的成本进行技术经济比较,并介绍了PEN在容器、薄膜、纤维及注塑材料中的应用。     

轮胎用PEN纤维与PET纤维性能研究

本文研究了PEN、PET 1100dtex、1670dtex纤维的原丝性能、捻线帘线性能、浸胶帘线性能。对浸胶后帘线进行了模拟硫化、蠕变、弯曲疲劳和粘合性能测试。浸胶PEN纤维帘线弯曲疲劳性能表现差之外,PEN纤维在原丝、捻线帘线、浸胶帘线保持更好的尺寸稳定性、更高的模量。PEN纤维浸胶帘线与橡胶具有良好的粘合性能。     

Fabrication of Functionally Graded SOFC by APS

Atmospheric plasma spray (APS) was used to prepare the planar positive/electrolyte/negative (PEN) and mono-block layer built (MOLB) type PEN solid oxide fuel cells (SOFCs). On the basis of the spraying conditions optimized previously and the self-developed functionally graded powder feeder system, two types of PEN cells were fabricated. Then the microstructure and material composition of the PEN cells were analyzed. The results show that graded layers formed between the electrodes and electrolyte. Moreover, the material composition and the porosity of the graded layers vary gradually. In particular, the porosities of the resultant anode and cathode reach 32.74 and 32.24%, respectively. Using the AC complex impedance technique, the conductivity of the MOLB type composite electrode is tested. The electrical conductivity of the MOLB type composite electrode with the graded layers is larger than that without the graded layers. This article is an invited paper selected from presentations at the 2007 International Thermal Spray Conference and has been expanded from the original presentation. It is simultaneously published in Global Coating Solutions, Proceedings of the 2007 International Thermal Spray Conference, Beijing, China, May 14-16, 2007, Basil R. Marple, Margaret M. Hyland, Yuk-Chiu Lau, Chang-Jiu Li, Rogerio S. Lima, and Ghislain Montavon, Ed., ASM International, Materials Park, OH, 2007.     

Carbon nanotube networks on different platforms

Carbon nanotube (CNT) networks are an emerging class of material with potential applications that range from biotechnology to sensors. However, the design and fabrication of CNT networks with specific properties necessitates a deep understanding on how a variety of factors affect the performance of these materials. Of particular interest is how the substrate on which the CNT networks are assembled also influences on the applicational aspects of the CNT network. In this review, we overview the variety of substrates reported as CNT networks supports, and the different applications of these networks. Substrates can be varied from rigid to flexible to porous materials. Interestingly, the method of network preparation and the nature of the scaffold have a direct influence on the properties and the potential applications of the final material.     

PEN/PPS长丝的制备及共混比例对长丝性能的影响

将PEN(聚萘二甲酸乙二醇酯)和PPS(聚苯硫醚)切片共混熔融纺丝,得到耐温性好且可纺性强的共混长丝。为了探究共混比例对长丝性能的影响,将PEN/PPS以100/0、97/3、95/5三种比例(质量比)共混,并对长丝进行力学性能、耐化学性能、耐热性能、热缩率测试。结果表明:PPS的少量添加对PEN长丝的熔点影响不大,但PEN/PPS(95/5)共混长丝的结晶度远远小于其他两种比例的长丝;PEN/PPS(97/3)共混长丝同时具有高强力和高伸长率,且其在170℃热处理下强力变化率低,较为稳定;三种长丝在70℃下都具有较好的耐酸碱性,但PEN/PPS(97/3)共混长丝在90℃的温度下也能维持一定的酸碱稳定性;虽然三种长丝的热收缩率都较高,但PEN/PPS(97/3)共混长丝的收缩率最小。     

A review on the mechanical and electrical properties of graphite and modified graphite reinforced polymer composites

Carbon materials particularly in the form of sparkling diamonds have held mankind spellbound for centuries, and in its other forms, like coal and coke continue to serve mankind as a fuel material, like carbon black, carbon fibers, carbon nanofibers and carbon nanotubes meet requirements of reinforcing filler in several applications. All these various forms of carbon are possible because of the element's unique hybridization ability. Graphene (a single two-dimensional layer of carbon atoms bonded together in the hexagonal graphite lattice), the basic building block of graphite, is at the epicenter of present-day materials research because of its high values of Young's modulus, fracture strength, thermal conductivity, specific surface area and fascinating transport phenomena leading to its use in multifarious applications like energy storage materials, liquid crystal devices, mechanical resonators and polymer composites. In this review, we focus on graphite and describe its various modifications for use as modified fillers in polymer matrices for creating polymer-carbon nanocomposites.     

2,6-萘二甲酸合成技术进展

综述了2,6-萘二甲酸合成技术的国内外研究进展,主要介绍了2,6-二烷基萘氧化法、β-甲基萘酰化氧化法的特点,指出2,6-二甲基萘氧化法是较具竞争力的生产方法,建议充分利用我国的萘和烷基萘资源来制备2,6-二甲基萘,以降低生产成本。     

Influence of PET and PET/PEN Blend Packaging on Ascorbic Acid and Color in Juices Exposed to Fluorescent and UV Light

ABSTRACT: Apple and orange juices packed in polyester bottles were stored in dark, intense fluorescent (1500 lux), and UV light conditions in temperature-controlled (22 °C) chambers and monitored more than 7 mo for ascorbic acid content and color changes. Polyester beverage bottles were made of polyethylene terephthalate (PET), or PET blended with 0.25%, 1%, and 4% polyethylene naphthalate (PEN). The cut-off wavelength ranged from 322 nm for PET to 373 nm for the 4% PEN/PET blend. Spectral irradiance, visible light intensity, and light distribution were evaluated in the light chambers and compared with supermarket display lighting and outdoor daylight conditions. Only the UV chamber and sunlight showed significant irradiance at wavelengths below 400 nm. Ascorbic acid (AA) degradation and concurrent color changes occurred in both juices during storage in all 3 lighting conditions and in all 4 bottle types. Zero-order reaction kinetics described the AA degradation rate for all treatments. Apple juice stored in UV had a significantly higher ( P < 0.05) AA degradation rate than juice stored in the dark or in fluorescent light. Under UV conditions, apple juice in PET/ PEN bottles had a lower AA degradation rate than the juice in PET bottles. AA degradation in orange juice was less affected by UV exposure than in apple juice. Both juices darkened over time when stored in dark and fluorescent conditions, whereas UV exposure caused some initial bleaching of color before darkening. The bleaching effect was reduced in apple juice stored in the PET/PEN bottles.