聚乙类醇与钛酸酯偶联剂化学反应的X射线光电子能谱研究

用X射线光电子能谱研究了聚乙烯醇（PVA）与三（二辛基焦磷酰氧基）钛酸异丙酯偶联剂（NDZ－201）的化学反应,PVA的一些C－OH官能团与NDZ－201钛酸酯偶联剂反应形成了CPVA－O－Ti-O－CPVA键,通过该键PVA分子链被联成憎水性的三维聚合物网络据此提高了钛酸酯偶联剂改善高铝水泥／聚乙烯醇（HAC／PVA）基无宏观缺陷（MDF）复合材料湿敏性的作用机理。     

钛酸酯偶联剂及其应用

本文介绍了钛酸酯偶联剂及国内外生产企业,对钛酸酯偶联剂的品种、作用机理、选型、使用方法、应用等都作制了较为详尽的论述。     

焦磷酸酯型钛酸酯偶联剂的合成与应用

以钛酸四异丙酯（１）、焦磷酸二异辛酯（２）为原料,合成三（二异辛基焦磷酰氧基）钛酸异丙酯。优化试验参数为：原料（２）／（１）＝３．４（摩尔比）,反应温度９０℃,反应时间２ｈ,产物收率达８７．９％。该钛酸酯偶联剂对碳酸钙表面进行处理,再用来填充聚乙烯,冲击强度可增加２０％以上。     

钛酸酯偶联剂及其我国发展建议

本文综述了近年来新出现的一些以钛酸酯为中心的偶联剂的概况、偶联剂用量的确定、无机填料的处理、新型表面改性剂及关于加快我国偶联剂工业发展的几点建议。     

螯合200型钛酸酯偶联剂的合成及应用

以异丙醇、四氯化钛、植物油酸等为原料,经合成、螯合等工序制备螯合200型钛酸酯偶联剂。其在PVC硬管上应用,可改善PVC硬管的性能,有较好的经济效益。     

水溶性钛酸酯偶联剂的合成与应用

以五氧化二磷、辛醇、正钛酸异丙脂为原料,乙二醇为螯合剂,采用三乙醇胺生成季铵盐的方法合成了一种水溶性钛酸酯偶联剂,并介绍了其在水性涂料中的应用。     

硬脂酸-钛酸酯偶联剂改性重质碳酸钙粉体研究

以硬脂酸和钛酸酯偶联剂为复合改性剂,无水乙醇为分散剂,采用湿球磨法对重质碳酸钙粉体进行改性。以活化度为评价指标,通过单因素实验考察球磨时间、球磨转速、改性剂用量、改性剂配比对改性效果的影响。通过正交实验进一步优化得到改性工艺条件：球磨时间为1.5 h、球磨转速为350 r/min、改性剂用量为2.0%（质量分数）、m（硬脂酸）∶m（钛酸酯偶联剂）=1∶3。在优化条件下,改性样品活化度为99.4%、吸油值为14.27 g（以100 g改性样品计）、沉降体积为1.08 mL/g、粒度D50为1.58 μm。     

钛酸酯偶联剂对碳酸钙表面改性效果的研究

本文就钛酸酯偶联剂对钛酸钙的表面改性效果进行了一些研究 ,测试了改性前后UP树脂浇注体、GFRP的力学性能 ,并对其作用机理进行了一些探讨     

Surface Chemical Composition of Size-Fractionated Urban Walkway Aerosols Determined by X-Ray Photoelectron Spectroscopy

Most aerosol chemical characterization studies to date involve bulk particle analysis. The surface chemical and physical properties of aerosol particles have rarely been analyzed, despite the particles’ potential health impacts and interactions with gas in the atmosphere. Aerosol particles ranging from 0.056 to 10 μm in size collected using a 10-stage impactor sampler from a busy walkway in a downtown area of Hong Kong were analyzed using X-ray photoelectron spectroscopy (XPS), a technique providing both elemental and chemical state information about the particle surfaces. Six key elements were detected: nitrogen (N), sulfur (S), calcium (Ca), silicon (Si), oxygen (O), and carbon (C). Carbon was the dominant species on the surfaces of all particles regardless of their sizes. A higher carbon concentration was found on the surfaces of the 0.056–0.32 μm particles. The N, Si, Ca, and O concentrations were higher on the surface of the 3.2–10 μm particles than in the smaller size fractions. Sulfur was mainly found on the surface of the 0.32–1.8 μm particles. High-resolution scans of C, N, and S were obtained to provide chemical state information about these elements. Aromatic C-H and aliphatic C-H were found to be the major carbon chemical states. Fullerenic carbon was detected on the surfaces of the finest (0.056–0.32 μm) particles. Oxygen- and nitrogen-containing organics were found on the surfaces of the 0.32–1.8 μm particles. Sulfur was present in the form of sulfates as expected. Ammonium salts, amide, and nitrate were found to form especially on the surfaces of aerosol particles in the nucleation, accumulation, and coarse modes, respectively. Silicates and carbonates were only discovered on the surfaces of coarse-mode particles (3.2–10 μm). The results suggest that both the chemical elements and their chemical states were significantly dependent on the size of the aerosol particles.

Copyright 2013 American Association for Aerosol Research     

X-ray Photoelectron Spectroscopy Study of High- and Low-Temperature Forms of Zirconium Titanate

X-ray photoelectron spectroscopy (XPS) spectra were measured for the high-temperature forms (quenched from 1500°C) of zirconium titanate and its solid solutions, the low-temperature forms (quenched from 1000°C), and cubic Ba(Zr_1/2Ti_1/2)O₃. Two distinct differences in the XPS spectra were noted between the high- temperature forms. The O 1 s spectrum of the high-temperature form consisted of two peaks of nearly equal intensities with a spacing of 2.2 eV, which was larger than the corresponding spacing of 1.6 eV, for Ba(Zr_1/2Ti_1/2)O₃, while the spectrum of the low-temperature forms was almost a single peak. The high-temperature form had an unassignable spectrum with a binding energy of 25 eV between the peaks of Zr 4 p and O 2 s . The unassignable spectrum could be a molecular orbital which had been hypothesized to form in these compounds.     

Use of X-Ray Photoelectron Spectroscopy to Study the Failure of an Adhesive Joint Between Two Polymers

The interface of the Kynar®-Nylon adhesive joint was examined by X-ray photoelectron spectroscopy. It was found that the failure was neither adhesive nor cohesive. XPS results indicated that the fracture path occurred through a weak boundary layer which migrated to the interface possibly during the bonding process. The weak boundary layer consists of molecules which have -(CH₂)_n and (CF₂)_n structural units which are probably present as low molecular weight impurities formed during the polymerization of vinylidene fluoride or subsurface contaminants in the samples. This work presents the first conclusive evidence that confirms the existence of a weak boundary layer in an adhesive joint.     

Use of X-Ray Photoelectron Spectroscopy to Study the Failure of an Adhesive Joint Between Two Polymers

The interface of the Kynar®-Nylon adhesive joint was examined by X-ray photoelectron spectroscopy. It was found that the failure was neither adhesive nor cohesive. XPS results indicated that the fracture path occurred through a weak boundary layer which migrated to the interface possibly during the bonding process. The weak boundary layer consists of molecules which have -(CH₂)_n and (CF₂)_n structural units which are probably present as low molecular weight impurities formed during the polymerization of vinylidene fluoride or subsurface contaminants in the samples. This work presents the first conclusive evidence that confirms the existence of a weak boundary layer in an adhesive joint.     

硅烷偶联剂/聚乙烯醇改性石膏的防水性能

以硅烷偶联剂A151和聚乙烯醇(PVA)为防水剂,研究石膏制品的防水性能.从微观形貌、接触角、石膏晶体表面的元素分布等方面,探讨其防水机理.结果表明,A151可以将亲水的石膏表面转变为憎水表面;PVA能在保留石膏制品质轻的同时,填充毛细孔,提高强度性能;两者复合使用可以显著提高石膏制品的防水性能.A151/PVA复合防水剂的制备工艺简单,并适用于非碱性环境,对石膏制品质轻的特性无明显影响.浸水2h后,试样的吸水率仅为0.9％,其湿强仍然是普通石膏制品干强的1.4倍.     

甲苯二异氰酸酯与水基聚乙烯醇胶粘剂交联反应的研究

本文研究甲苯二异氰酸酯 (TDI)与聚乙烯醇 (PVA)胶水的交联反应。采用正交实验法 ,探讨PVA的浓度、TDI的加入量及交联反应的温度等因素对该胶粘剂 180°剥离强度的影响。并结合该交联反应进行程度 ,即交联度的结果一起讨论该交联反应。结果发现少量TDI的加入 ,可较大程度地提高PVA胶水的粘合性能和耐水性能     

X-Ray Photoelectron Spectroscopy Investigation of Pd-Beta Zeolite Catalysts with Different Acidities

Three different H-Beta zeolites with SiO₂/Al₂O₃ molar ratios of 300, 150 and 25 were loaded with palladium by evaporation–impregnation method using Pd(NO₃)₂ as a precursor. Dependence between the electronic states of Pd as a function of the acidity of Beta zeolite was studied by XPS for calcined and reduced samples. The dependence of the electronic states of Pd on the support was detected to have a complicated character and to be influenced by various factors such as metal loading, density of the imperfections in the zeolitic framework and proton localization. In calcined zeolites mainly agglomerated PdO and AlPd _x O crystallites were detected referring to interaction of palladium with the support. Reduction of PdO led to formation of metallic Pd_n clusters, which further reduced to [Pd_n–H_m]^m+ complexes and AlPd _x O complexes. The increase of the reduction temperature seems to enhance interactions of Pd_n clusters with imperfect [AlO _x ⁻] components instead of protons, especially in less acidic samples due to enhanced agglomeration of palladium particles outside the pores of the zeolite. The fraction, size and shape of the formed species were detected to be sensitive to the acidity of the support.     

Studies of Chemical Bonding in Glasses by X-Ray Emission Spectroscopy

Silicon and aluminum K β band X-ray emission spectra of a series of lithia-aluminosilica (LAS) glasses were determined using the X-ray spectrometric systems of commercially available electron microprobes. Comparison with spectra of reference materials, including glassy and crystalline forms of silica, high-quartz-phase crystals of the L:A:S-1:1:2 (mol ratio) composition (high-eucryptite), and 6- and 4-coordinated aluminum oxides, led to tentative assignment of spectral peaks to specific electronic transitions. Molecular orbital theory and crystallographic structural data were used to assign bands in crystalline materials. The LAS glass spectra indicated progressive bond weakening with decreasing silica content; the K β peak shifts permitted approximate calculation of the decreases in Si–O and Al–O bond energies, which were as great as 30 kcal/mol relative to SiO₂ (for the L:A:S-1:1:2 glass).     

二异氰酸酯与聚乙烯醇胶水固化反应的研究

利用二异氰酸酯（ＴＤＩ和ＨＤＩ）与聚乙烯酯固化反应的产物不溶性判断该反应进程,研究反应温度,反应物配比等对反应的影响,研究表明,少量一二异氰酸酯的加入,较大程度地提高聚乙烯醇胶水的耐水性能。