Zinc Coated Steel/Epoxy Adhesive Systems: Investigation of the Interfacial Zone by FTIR Spectroscopy

The present study takes advantage of the ability of Fourier Transform Infrared Spectroscopy (FTIR) for the analysis of ultrathin organic films on metals. FTIR in the reflection mode (IRRAS) is used in order to study the interaction of ultrathin films of dicyandiamide (hardener of most one-pack epoxy resins) with various substrates, model ones such as gold or zinc and industrial ones such as steel and zinc-coated steels.

Pure zinc surfaces and, to a lesser extent, zinc-coated steels are shown to react with dicyandiamide after heating at 180°C, as evidenced by the frequency shift of the absorption band (at about 2200 cm^-1) characteristic for nitrile groups. As real systems consist of thick layers of a fully formulated adhesive cured onto a metallic substrate, the direct investigation of such a buried interphase is no longer possible by FTIR and by most of the known spectroscopies. Some mechanically tested specimens are then analysed, after failure, by FTIR microspectrometry. The spectra obtained, corresponding to the fracture initiation zone which is about 100 μm in diameter, advocate for the presence of an ultrathin layer of modified polymer still covering the substrate.     

901快速强力胶的研制

详细论述了一种新型改性SBS溶剂型胶粘剂的配方设计、制备工艺、基本性能等有关问题。     

浅谈一次盐水的工艺指标控制

介绍了一次盐水的各项工艺指标对生产的影响以及稳定控制这些指标的方法，强调了在生产中控制好一次盐水的工艺指标是影响产品质量及离子交换膜使用寿命的关键。     

Thermodynamic Criteria for the Maximum and Minimum Strength of Fibre-Reinforced Composite Materials

The overall performance and reliability of composite materials are, in most cases, dependent upon the behaviour of the reinforcement-matrix interface, particularly upon its ability to transfer stress.

A theory for predicting thermodynamic conditions for the maximum and zero-adhesion at the reinforcement-matrix interface is tested in this paper, based on experimental data. Proposed is a model of the relationship between mechanical properties of composite materials (tensile strength, flexural strength, Young's modulus and impact resistance) and energetic properties of matrix and reinforcement expressed by the energy ratio a = γ_l/γ₂.     

国产脱砷剂及其应用

介绍了石油烃中砷的存在形式 ,石脑油中砷含量及对催化剂的危害 ,分析了脱砷机理 ,阐述了国产脱砷剂的类型、型号、特点 ,以及选用原则与工业应用情况。     

凹凸棒粘土用作高水速凝注浆悬浮剂

以凹凸棒粘土作为高水速凝固化充填材料的悬浮稳定剂，考察了不同制浆机械对凹凸棒粘土制浆率的影响。采用高剪切混合乳化机预制的1％凹凸棒粘土浆配制高水速凝固化充填材料甲、已料单浆可获得满意的悬浮稳定效果。其充填体结石抗压强度早期发展迅速，后期持续增长。采用此工艺，注浆料的材料成本仅增加2％。     

NBR／EPDM的增容共混研究

本文采用第三组份增容途径,改善了NBR/EPDM并用胶的相容性、加工性和力学性能。通过对不同增容体系的研究对比,发现不同增容剂的增容效果差异很大,其巾以EVA-14增容效果最为显著,加入该增容剂的并用胶,在适当的工艺条件及硫化体系下,可获得最佳力学性能。本文还研究了不同增容剂对并用炭黑胶各种性能的影响,可以做到在不降低并用胶的力学性能的同时,提高并用胶的耐热空气老化、耐大气老化和耐臭氧老化性能.透射电镜实验和动态力学谱图证明了加与未加增容剂时,NBR/EPDM并用胶均为两相结构,增容剂起表面活性剂的作用,加强了两相界面间的相互作用,使分散相EPDM细微化和均匀化。     

氯化聚丙烯改性胶粘剂的合成及粘附性能研究

以甲苯为溶剂，过氧化二苯甲酰(BP0)为引发剂，通过自由基聚合，采用甲基丙烯酸羟乙酯(HEMA)和苯乙烯(St)接枝改性氯化聚丙烯(CPP)。研究了不同苯乙烯用量、不同反应温度、不同反应时间、不同引发剂用量对改性氯化聚丙烯胶粘剂粘附性能的影响，得出较佳的工艺条件为反应温度90℃，反应时问2h，原料配比m(CPP)：m(HEMA)：m(St)：m(BPO)=50：0．5：0．6：0．15。     

偶联剂对地砖用PVC填充材料相态结构和力学性能的影响

研究了钛酸酯类偶联剂和硅烷类偶联剂对钙矿、硅酸盐填充的PVC填允材料力学性能、相态结构、密度、热失重率及吸水伸长率和耐热阻燃性能的影响。结果表明,偶联剂可改善填充PVC的抗冲性能,降低其拉伸强度,扫描电镜分析表明,填料越细,分散越均匀,越易被PVC树脂所包覆,力学性能越好,研究得到了比重大、热失重率低、吸水伸长率小、阻燃耐烧灼性好的高填充PVC硬质塑料地板砖。     

Imide-aryl ether benzoxazole random copolymers

Novel imide-aryl ether benzoxazole copolymers were prepared and their morphology and mechanical properties investigated. A key feature of these copolymers is the incorporation of a benzoxazole moiety by the use of 2,2′-bis[4-(3-aminophenoxy)phenyl]-6,6′-bibenzoxazole or 2,2′-bis[4-(4-aminophenoxy)-phenyl]-6,6′-bibenzoxazole as co-diamines in polyimide syntheses. The preparation of these diamines involved the nucleophilic aromatic substitution of 2,2′-bis(4-fluorophenyl)-6,6′-bibenzoxazole with either 3- or 4-aminophenol in the presence of K₂CO₃. The diamines were co-reacted with various compositions of pyromellitic dianhydride (PMDA) and 4,4′-oxydianiline (ODA) to synthesize the desired poly(amic acids). Films were cast and cured (350°C) to effect the imide formation, affording films with elongations between 40 and 110% and moduli in the 2000–2750 MPa range. The copolymers exhibited good dimensional (T_g in excess of 300°C) and thermal stability. Wide-angle X-ray diffraction measurements on the copolymers showed that the ordered morphology characteristic of PMDA/ODA polyimide was retained. Improvements in the auto-adhesion were observed, particularly in those copolymers which displayed a T_g.