Polymer adhesives chemistry

Applications of ISS to polymer analysis can provide some extremely useful and unique information that cannot be obtained by other means. This makes it extremely complementary to use ISS with other techniques, such as XPS and static SIMS. Some particularly important applications include the analysis of oxidation or degradation of polymers, adhesive failures, delaminations, silicone contamination, discolorations, and contamination by both organic or inorganic materials within the very outer layers of a sample. XPS and static SIMS are extremely comple-mentar when used in these studies, although these contaminants often are undetected by XPS and too complex because of interferences in SIMS. The concentration, and especially the thickness, of these thin surfiice layers has been found to have profound affects on adhesion. Besides problems in adhesion, ISS has proven very useful in studies related to printing operations, which are extremely sensitive to surface chemistry in the very outer layers. 

In all the applications where silicones are used, the design of the polymer reactivity and the composition of the formulation require the development chemist to thoroughly understand both silicone chemistry and adhesion phenomena. 

D. H. Kaelhle, Computer-Aided Design of Polymers ami Composites, Marcel Dekker, New York, 1985 Physical Chemistry of Adhesion, Wiley, New York, 1971. 

XPS of Polymer Surfaces Analytical Applications Radiation Damage Surface Modified Electrodes Interfacial Chemistry and Adhesion Surface Chemistry and Catalysis Mineralogy and Geochemistry Microelectronics Processing... 

Most of the illustrative examples will come from polyimide-metal interface studies directed at investigating the role of interfacial chemistry in adhesion at these interfaces and the non-equivalence of polymer-on-metal and metal-on-polymer interfaces. 

Chemical synthesis methods are not only used for the synthesis of chemical compounds, but also for materials. Examples are silicones, polymers, adhesives and ceramic powders [1]. But if one compares the potential of chemical synthesis with the number of materials produced by these routes, one has to say that the potential of chemiced synthesis is only used to an extremely small extent. The focus of chemical research still is mainly directed to "new chemistry", generating new compounds. So far, sol-gel chemistry as an interesting route for material synthesis never has come to a real breakthrough in application and even is rarely used in silicon chemistry, although a large methodical overlap exists [2,3]. 

Thermoplastic Adhesives. The polymer adhesives described in the following sections are not used as extensively with wood as the thermosetting adhesives discussed earlier. However, they do illustrate many interesting principles of the chemistry of adhesion through organic polymers. 

Saunders, K.J. Organic Polymer Chemistry. An Introduction to the Organic Chemistry of Adhesives, Eibres, Paints, Plastics and Rubbers, 2nd Ed. Chapman and Hall London, Chapter 18, Epoxies, 1988 412-435. 

Vakula, V. A. Pritykin, L. H. "Foundation of Physical Chemistry of Polymer Adhesion," Khimia, Moscow, 1984. 

Chemistries A large majority of adhesive and coating Aims in the end-use state exist in the form of a polymer network. Chemistries for adhesives and... 

The science of adhesion is truly multi-disciplinary, demanding a consideration of concepts from such topics as surface chemistry, polymer chemistry, rheology, stress analysis and fracture mechanics. It is, nevertheless, important for the technologist to possess a qualitatively correct overall picture of the various factors influencing adhesion and controlling joint performance in order to make rational judgements concerning the selection and use of adhesives. 

This Institute has 410 technical and research members of whom 80 are research scientists and 120 are assistants. Professor Ye Zuozhou, a chemist and an archivist, was one of the four deputy directors. He was the host for my recent visit. This Institute has nine divisions engaged in cellulose chemistry, marine organic chemistry, turpene chemistry, polymeric adhesives, polymer composites and polymeric grouting compounds. 

This Institute has twelve departments and approximately 780 research and supportive personnel (approximately 450 research staff). Recently, they have taken approximately 30 college graduates as advanced degree candidates. Six of the departments of this Institute are polymer-or iented Polymer Chemistry, Organosilicone, Polymer Physics, Specialized Polymers, Functional Polymers and Polymer Composites. Several projects in high-temperature polymers, adhesives, and composites have been carried out under the direction of Professor Qian Renyuan, a well-known polymer physicist in PRC. A brief description of these projects follow ... 

Ethylene vinyl acetate (EVA) is a copolymer of polyethylene. It is similar in chemistry to PE,but it has some percentage of vinyl acetate (VA) included along the chains (Fig. 1.8). The amount of VA that is included, generally between about 5 and 20%, depends on the desired properties of the polymer. VA adds polarity, or adhesion, to the polymer and, so, improves the compatibility of the polymer with fillers and gives the polymer adhesive properties. Most blown film applications using EVA do so as layers in coextruded products, such as food and electronics packaging. 

A denotes adherend chemistry, B adherend structure and topography, C adhesive chemistry, D adhesive structure and topography, E interaction of polymers with metals, and F failure surfaces (locus of failure). 

W. D. Bascom and R. L. Patrick, "The Surface Chemistry of Bonding Metals with Polymer Adhesives", Adhesives Age, 17,... 

V. L. Vakula and L. M. Priiykin in Physical Chemistry of Polymer Adhesion,... 

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