吸水性热塑性橡胶——氧乙烯-氧丙烯-苯乙烯多嵌段共聚物的合成及性能

通过聚乙二醇、聚丙二醇、遥爪双羟基聚苯乙烯 3种预聚物以甲苯二异氰酸酯 (TDI)为偶联剂合成氧乙烯 -氧丙烯 -苯乙烯多嵌段共聚物。研究其合成条件、精制及表征 ,并研究其力学性能、吸水性及乳化性质。结果表明 ,某些组成的嵌段共聚物呈现热塑性弹性体行为 ,吸水率达到 5 0 0 %～70 0 %。     

"动态硫化"PVC/NBR型TPE的耐油性能研究

本文系统地研究了ＰＶＣ／ＮＢＶ型热塑性弹体，并与ＮＢＲ进行了对比。     

Laser scanning confocal microscope characterization of dye diffusion in nylon 6 fibers treated with atmospheric pressure plasmas

The effect of atmospheric pressure plasma treatment on wettability and dyeability of nylon 6 fibers is investigated. The plasma treatments resulted in an average of 10°–20° decrease in the advancing contact angle and 20°–30° decrease in the receding contact angle. An increased dye diffusion rate of nylon 6 fibers was observed using laser scanning confocal microscope (LSCM). Scanning electron microscope confirmed that the fiber surfaces were roughened, and X‐ray photoelectron spectroscopy showed that the polar groups on the fiber surfaces increased after the plasma treatments. As the plasma treatment time increased, a greater degree of etching was achieved and more polar groups such as hydroxyl and carboxyl groups produced on the surfaces of the nylon 6 fibers, leading to a better wettability and thus a better dyeability of the fiber. This study proved that LSCM may be effectively used in detecting the change of dye diffusion rate in nylon fibers treated with plasmas and the mounting medium should have a close refractive index as the fiber to avoid distortion of the fiber cross section image. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Preparation of polyethylene‐octene elastomer/clay nanocomposite and microcellular foam processed in supercritical carbon dioxide

Polyethylene‐octene elastomer (POE)/organoclay nanocomposite was prepared by melt mixing of the POE with an organoclay (Cloisite 20A) in an internal mixer, using poly[ethylene‐co‐(methyl acrylate)‐co‐(glycidyl methacrylate)] copolymer (E‐MG‐GMA) as a compatibilizer. X‐ray diffraction and transmission electron microscopy analysis revealed that an intercalated nanocomposite was formed and the silicate layers of the clay were uniformly dispersed at a nanometre scale in the POE matrix. The nanocomposite exhibited greatly enhanced tensile and dynamic mechanical properties compared with the POE/clay composite without the compatibilizer. The POE/E‐MA‐GMA/clay nanocomposite was used to produce foams by a batch process in an autoclave, with supercritical carbon dioxide as a foaming agent. The nanocomposite produced a microcellular foam with average cell size as small as 3.4 µm and cell density as high as 2 × 10¹¹ cells cm^?3. Copyright © 2005 Society of Chemical Industry     

Melt rheological properties of polypropylene–polyamide6 blends compatibilized with maleic anhydride‐grafted polypropylene

The melt rheological properties of binary uncompatibilized polypropylene–polyamide6 (PP–PA6) blends and ternary blends compatibilized with maleic anhydride‐grafted PP (PP–PP‐g‐MAH–PA6) were studied using a capillary rheometer. The experimental shear viscosities of blends were compared with those calculated from Utracki's relation. The deviation value δ between these two series of data was obtained. In binary PP–PA6 blends, when the compatibility between PP and PA6 was poor, the deformation recovery of dispersed PA6 particles played the dominant role during the capillary flow, the experimental values were smaller than those calculated, and δ was negative. The higher the dispersed phase content, the more deformed the droplets were and the lower the apparent shear viscosity. Also, the absolute value of δ increased with the dispersed phase composition. In ternary PP–PP‐g‐MAH–PA6 systems, when the compatibility between PP and PA6 was enhanced by PP‐g‐MAH, the elongation and break‐up of the dispersed particles played the dominant role, and the experimental values were higher than calculated. It was observed that the higher the dispersion of the PA6 phase, the higher the δ values of the ternary blends and the larger the positive deviation. Unlike uncompatibilized blends, under high shear stress with higher dispersed phase content, the PP‐g‐PA6 copolymer in compatibilized blends was pulled out from the interface and formed independent micelles in the matrix, which resulted in reduced total apparent shear viscosity. The δ value decreased with increasing shear stress. Copyright © 2006 Society of Chemical Industry     

热熔压敏胶的配方设计

为快速合理地确定热熔压敏胶的方案,可根据热熔压敏胶的本体性质和使用性质进行配方设计,以涌足不同基材和使用条件的要求。     

Erhöhung der Verschleißfestigkeit von Elastomerverarbeitungsmaschinen durch innovative Beschichtungsverfahren

Increasing the resistance to wear of elastomer processing machines by innovative coating processes A goal of the subsequent work is the evaluated of selected surface coating processes with respect to the attainable abrasion characteristics of the generated layers regarding to their suitability for the abrasion protection of elastomer processing equipment (e.g. interior kneading machines). Additionally the specifications of various commercial coating companies were layers compared to data concerning to the wear resistance of the created sections. On this base own experimental tests are performed dedicated to designated application cases and were evaluated by an abrasion test on its wearing properties. Apart from classical deposition‐welding, the Plasma‐Transferred‐Arc process, above all the innovative thermochemical techniques were applied. Due to of their steadily increasing market shares, particularly the arc and HVOF‐Spraying got in the center of attention thereby.     

Fatigue damage analysis based on energy parameters in reinforced polyamide

This article proposes an analysis method for the identification of the damage caused in a reinforced polyamide fatigue process through the evolution of the generated energy per cycle. Monotonous fatigue tests have been carried out at different stress levels using Polyamide 6 reinforced with short fibre glass tensile specimens. The loss of mechanical properties is measured using a damage parameter, defined as the variation in energy per cycle with respect to the initial conditions. Three clearly differentiated zones can be distinguished in the evolution of damage as a function of the energy per cycle. The first zone is one of deaccelerated rapid growth; in the second, the damage grows linearly, so that the damage growth speed can be determined as a function of the potential of variation of the stress applied; and finally, the third is a zone of accelerated growth of the damage until fracture.     

车辆装备用液压油的橡胶相容性要求及试验方法综述

如何评价液压油与橡胶的相容性已引起了业内人士的广泛关注.该文主要对液压油的橡胶相容性要求及国内外相关机构为此而制定的12种标准试验方法做一综述,以期为液压油的研发与实际使用提供一定参考.