On the sliding wear of nanoparticle filled polyamide 66 composites

The tribological properties of polyamide 66 (PA66) composites, filled with TiO₂ nanoparticles, short carbon fibres, and graphite flakes, were investigated. Sliding tests were performed on a pin-on-disk apparatus under different contact pressures, p, and sliding velocities, v. It was found that nano-TiO₂ could effectively reduce the frictional coefficient and wear rate, especially under higher pv (the product of p and v) conditions. In order to further understand the wear mechanisms, the worn surfaces were examined by scanning electron microscopy and atomic force microscopy. A positive rolling effect of the nanoparticles between the material pairs was proposed which contributes to the remarkable improvement of the load carrying capacity of polymer nanocomposites.     

Non-isothermal Crystallization Kinetics of Polyamide 6/Diamine-modified MWNTs Nanocomposite

The non-isothermal crystallization kinetics of polyamide 6/diamine-modified multi-walled carbon nanotube (PA6/D-MWNT) nanocomposite was investigated by differential scanning calorimetry (DSC). The modified Avrami equation, the Ozawa equation and the combined Avrami/Ozawa equation were employed to analyze the non-isothermal crystallization data. The crystallization activation energies were also evaluated by the Kissinger method. It was found that the combined Avrami/Ozawa equation could successfully describe the non-isothermal crystallization process. The results showed that D-MWNTs not only acted as effective heterogeneous nucleating agents for PA6 and noticeably increased the crystallization temperature of PA6, but also influenced the mechanism of nucleation and crystal growth of PA6 and then reduced the overall crystallization rate of the neat PA6 matrix. The crystallization activation energy for the nanocomposite sample was greater than that of the neat PA6, which indicated that the addition of D-MWNTs hindered the mobility of PA6 chain segments.     

Sepiolite needle-like clay for PA6 nanocomposites: An alternative to layered silicates?

This paper presents a study of polyamide 6/sepiolite clay nanocomposite, obtained by melt compounding in a mini twin-screw extruder, and characterised in terms of morphology (SEM and TEM analysis) and mechanical properties of the composite, along with their crystallinity and crystal structure of the semi-crystalline matrix. The tensile test results are interpreted in terms of two micromechanical models: the Halpin–Tsai model for stiffness and the Pukanszky equation for yield stress, and compared with the results on polyamide 6/smectite montmorillonite (MMT) clay nanocomposites from selected publications. This comparison between sepiolite (fibre-like shape, 1D) and smectite (platelet-like, 2D) clays offers an interesting model-study on the effect of nanofiller shape and orientation on final mechanical properties. It shows that 1D fillers are expected to provide better reinforcement in the case of oriented systems, whereas platelets should be more efficient in isotropic composites. It was demonstrated that sepiolite has a higher reinforcing efficiency (higher effective aspect ratio) than MMT in PA6 and a good filler-matrix interface, due to strong hydrogen bonds between silanol groups on the sepiolite surface and amide groups of PA6.     

分散金黄SE-3R在棉锦交织物浸染中的应用

介绍了棉锦交织物的特点、浸染对染料的要求。通过生产实践,证明了分散金黄SE－3R染料在锦纶浸染染色上的优异性能。不仅可取代价高的中性和酸性染料染各类棉锦交织物以及适宜涤锦织物和锦粘织物。     

涤锦摩丝桃皮绒染整工艺

详细介绍了涤锦摩丝桃皮线染整生产工艺,并对关键工序进行了分析和讨论。     

碱性电池密封圈欠注原因分析与对策

结合尼龙66(PA66)碱性电池密封圈尺寸小、精度要求高的特点,全面分析了预防电池密封圈欠注的设计及制造的关键技术.列出了碱性电池密封圈欠注的原因,系统阐述了电池密封圈注塑中欠注缺陷的解决方法.     

Enhanced electrochemical properties of a Si-based anode using an electrochemically active polyamide imide binder

Polyamide imide (PAI), one of the classes of copolyimides containing both high mechanical properties and processibility, is used as a polymeric binder of a Si particulate electrode. The initial coulombic efficiency is improved from 28.9% (Si-PVdF) to 74.9% (Si-PAI) by introducing a PAI binder into a Si-based electrode. Variations in thickness measured at various states of charge (SOCs) and depths of discharge (DODs) indicate that the PAI binder is a much more effective restraint on volume expansion in active Si materials during the charging process than poly(vinylidene fluoride) (PVdF) binder. The discharge capacity of Si-PAI electrodes is approximately 1700 mAh g⁻¹ after 20 cycles, which is attributed to the excellent maintenance of an electrical-conducting network during cycling.     

棉锦纶长丝蚕丝提花织物的开发

探讨棉锦纶长丝蚕丝交织嵌条提花织物的生产工艺。首先对锦纶长丝进行络丝,单独整经,控制好相对湿度;在浆纱工序虽为异经产品仍采用锦纶长丝和棉纱进同一浆槽的工艺;在织造工序采用分纱式储纬器、分绞棒和橡胶边撑;染整采用两正两反烧毛工艺和酶退浆、氧漂工艺,可顺利在棉织设备上开发棉锦纶长丝蚕丝交织嵌条提花织物。织机效率达到91%,产品下机质量达到美标4分制标准,布面风格达到设计要求。     

尼龙基复合材料的增韧和增强

采用合适的界面改性剂,并对高岭土表面改性,研制的高岭土/尼龙6复合体系,达到了既增韧又增强的目的;以马来酸酐接枝聚乙烯和三元乙丙橡胶为界面相容剂,研制的尼龙6/聚烯烃共混物,提高了冲击强度,降低了吸水率。