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341.
Model samples of the interface of an adhesive joint containing small levels of aminopropyl triethoxysilane (APS) have been prepared in order to examine the interface formed with an aluminium substrate. X‐ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF‐SIMS) have been used to analyse and image the interface region in between the aluminium and an epoxy adhesive in order to ascertain the reactions by the organosilane which is present as a minor component within the system. It was found that APS was present at the interface between the adhesive and the substrate and that it had reacted with the substrate forming a covalent bond and was also crosslinked within the adhesive. Evidence of near to full hydrolysis of APS is also present within the spectra. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
342.
A study of the mechanism of gluing between plasma-modified styrene-butadiene elastomer (SBS) surfaces and polyurethane (PU) adhesives is presented in this paper. The plasma treatment was carried out employing low-pressure O2 plasma generated by an RF discharge (13.56 MHz). FTIR-ATR spectroscopy and peel tests were utilized to characterize the SBS surfaces before and after the plasma treatment. It was found that hydroxyl groups are mainly created on the SBS surface by the plasma treatment and their concentration reveals very good linear correlation with the peel strength of the SBS-PU joints. The grafting of phenyl isocyanate (analog of the PU curing agent) into the plasma-treated SBS surface was also investigated. The process was performed at 353 K, that is at temperature in which the adhesive-bonded joints were made. It was shown that all hydroxyl groups on the SBS surface react with isocyanate groups forming carbamate bonds. The results obtained in this work strongly confirm the conception of the adhesion by chemical bonding between SBS and PU. 相似文献
343.
CHEN Shuanhu & ZHANG Lei Department of Chemistry Northwest University Xi''''an China 《中国科学B辑(英文版)》2005,48(Z1)
The synthesis of a novel melamine-glucose adhesive that is similar to urea-formaldehyde adhesive is reported in this paper. The conditions of synthesis, such as the initial pH, the quantity of catalyst, the temperature of reaction, the percentage of each reactant and the time of reaction, were optimized by using the orthogonal experimental method. 相似文献
344.
H. Lawrence Helfer Robert L. McCrory Hugh M. Van Horn 《Journal of statistical physics》1984,37(5-6):577-588
Very accurate Monte Carlo calculations for the one-component plasma (OCP) have been compared with the results of Slattery, Doolen, and DeWitt.(1,2) We confirm their results and also find a slight dependence of the calculation of the internal energy per particle uponN, the number of particles. A detailed investigation forN=108 permits us to evaluate the Helmholtz free energy for an OCP fcc lattice. As is usually believed, we find that the bcc lattice is more stable than the fcc lattice. The transition from the liquid to the fcc lattice phase occurs when
fcc = 196 ± 1. A three-dimensional modified cubic procedure, capable of achieving high accuracy in using tables of two-particle interaction potentials, is described in Appendix B. 相似文献
345.
蓖麻油聚氨酯/聚取代乙烯互穿网络聚合物作为带锈涂料及粘合剂的可能性 总被引:2,自引:0,他引:2
在室温用氧化还原引发剂将蓖麻油、甲苯二异氰酸酯及取代乙烯合成了蓖麻油聚氨酯/聚取代乙烯互穿网络聚合物(IPN),研究了不同组成对带锈铁板搭接剪切强度的影响。指出搭接剪切强度随取代乙烯均聚物的玻璃化温度增加而增。NCO/OH之比愈大,搭接剪切强度也愈大。以蓖麻油聚氨酯/(丙烯腈-苯乙烯)共聚物的反应液作为带锈铁板的涂料,其涂膜性能良好。用扫描电镜观察了此种涂料与带锈铁板的结合状态,并讨论其成因。 相似文献
346.
采用简单的激光刻蚀方法制备了具有类“菜花”状多级结构的粗糙聚二甲基硅氧烷(PDMS)膜, 并用CCD与高敏感性微电力学天平观察和测量PDMS表面对水的吸附情况. 结果表明, 该膜表面具有超疏水性, 同时对水滴具有超低的吸附力. 还对其表面特殊多级结构产生的机理进行了分析, 并探讨了在化学组成和表面结构对超疏水性以及吸附性产生的影响. 相似文献
347.
H. G. Wiedemann 《Journal of Thermal Analysis and Calorimetry》1998,52(1):93-107
Egyptian mural paintings, polychromatic sculptures and mummy coffins exhibit a remarkable durability, ranging over millennia. This phenomenon can be explained by the dry, non-corrosive climate of the Nile valley and/or by the knowledge and experience with which Egyptian craftsmen developed skills to conserve items and materials for eternity. Investigations concerning the timber and covering or protecting layers of mummy coffins are reported. The experimental results were obtained by means of thermal analysis and X-ray diffraction. The interpretation sheds light on the ancient techniques applied.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
348.
R. Cristescu I.N. Mihailescu A. Doraiswamy G. Westwood S. Stafslien D.B. Chrisey 《Applied Surface Science》2009,255(10):5496-5498
Mussels secrete specialized adhesives known as mussel adhesive proteins, which allow attachment of the organisms to underwater marine environments. Obtaining large quantities of naturally derived mussel adhesive proteins adhesives has proven to date rather problematic, thus, synthetic analogs of mussel adhesive proteins have recently been developed. We report deposition of 1:100 and 1:1000 poly[(3,4-dihydroxystyrene)-co-styrene)] mussel adhesive protein analogs by matrix assisted pulsed laser evaporation (MAPLE) using an ArF* excimer laser source. The deposited films have been evaluated for their antifouling behavior. The MAPLE-deposited synthetic mussel adhesive protein analog thin films are homogenous and adhesive, making the use of these materials in thin film form a viable option. 相似文献
349.
In this work, we report a facile and effective strategy to generate patterned wrinkles. This strategy includes first adhering a thin poly(dimethylsiloxane) (PDMS) film (<82 µm) on porous conductive adhesive tape (CAT), followed by sputter coating of Au onto PDMS under vacuum condition, which results in formation of patterned wrinkles on the Au‐PDMS bilayer. CAT was found to induce local stretching of PDMS thin film, which was the key for controlled wrinkle formation. Compared with previous wrinkling methods, our strategy is simpler and gives smaller feature sizes (down to 300 nm).
350.
G. Tsamasphyros K. Kalkanis P. Maroulas G. I. Anthoulis O. Grigoryeva 《Macromolecular Symposia》2009,286(1):42-48
The current work focuses on the testing of a novel material used as an adhesive film in Composite Patch Repair (CPR). A series of Differential Scanning Calorimetry (DSC) results along with various curing cycles not only led to the optimum material composition but also demonstrated the compatibility to the composite pre-impregnated patches. This in turn was subjected to mechanical testing including shear strength measurements. The substrate was chosen to be 2017 T4 aluminium alloy which is customarily used in the aerospace industry, taking into account that CPR is a technique mainly applied in this field. The subsequent surface preparation of the specimens was investigated for the specified context resulting to the selection of the Ferric Sulphate Sulphuric acid etching process. Finally, a series of specimens representing actual skin repairs were created and subjected to cyclic loading, specifying the suitability of the novel material, compared to commercially available materials. 相似文献