Preparation and characterization of PVA/OMMT composites

In this study, polyvinyl alcohol/organically modified montmorillonite (HDA/MMT; organoclay) composite was prepared for the intercalation processes. Firstly, the rheological behavior of aqueous montmorillonite dispersions was investigated as a function of solid content. Hexadecylamine (HDA) was added to the montmorillonite dispersion (2%, w/w) in different concentrations in the range of 5 × 10^?4 – 9 × 10^?3 mmol/L. The basal spacing of the organoclay (OMMT) was studied by X‐ray diffraction. The FTIR spectra are obtained from the modified montmorillonite products, which revealed the characteristic absorbencies after treatment with HDA. HDA/MMT/PVA composite, which was produced by the reaction of 1 wt % PVA solution with organoclay complex, is characterized by the rheology, electrokinetic, XRD, FTIR, and SEM techniques. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:2315–2323, 2006     

Enhanced wear resistance of ultra-high molecular weight polyethylene fibers by modified-graphite oxide

A simple and feasible method to enhance the wear resistance of ultra-high molecular weight polyethylene (UHMWPE) fibers was reported. The graphite oxide (GO) prepared using improved Hummer's method was surface modified with hexadecylamine to improve its compatibility with UHMWPE. Combined with well-dispersion of modified-GO (m-GO) in dichloromethane and the fact that the viscosity of UHMWPE suspension can be decreased by dichloromethane, the well dispersed m-GO/dichloromethane was added into UHMWPE suspension to improve m-GO dispersion in UHMWPE fibers. Finally, UHMWPE fibers with different m-GO concentration were prepared using gel spinning technology. The effect of m-GO concentration on the structure and properties of modified UHMWPE fibers were investigated. The results indicated that the melting temperature and crystallinity of m-GO modified UHMWPE fibers increased with increasing of m-GO concentration, while the fiber's crystal sizes and orientation increased, thus the tensile strength of m-GO modified UHMWPE fibers remained almost undamaged. The introduction of m-GO is beneficial to the formation of smooth transfer film on fiber's surface, which enhanced the self-lubrication of UHMWPE fibers. Compared with pure UHMWPE fiber, the UHMWPE fiber containing 1.5 wt% m-GO had enhanced wear resistance by 55.4% and still maintained high tensile strength of 29.98 cN dtex⁻¹.     

新型表面活性剂琥珀酸单十六酰胺磺酸钠的合成与性能研究

在1,2-二氯乙烷溶剂存在下,十六胺与顺丁烯二酸酐经酰胺化,再与Na2SO3磺化制成了新型表面活性剂琥珀酸单十六酰胺磺酸钠（SHAS）,并用单因素优选法对酰胺化反应条件进行了筛选。得到的最佳反应条件为：十六胺与顺丁烯二酸酐投料物质的量比1：1．18,酰胺化反应温度70℃,酰胺化反应时间20min;顺丁烯二酸酐与亚硫酸钠投料物质的量比1：1．10,磺化反应温度70℃,磺化反应时间3h。目的产物收率〉98％,对SHAS各项应用性能进行了测定。