Adhesion between polymers

One way of improving the adhesion between polymer and filler is to improve the level of wetting of the filler by the polymer. One approach, which has been used for many years, is to coat the filler with an additive that may be considered to have two active parts. One part is compatible with the filler, the other with the polymer. Probably the best known example is the coating of calcium carbonate with stearic acid. Such coated or activated whitings have been used particularly with hydrocarbon rubbers. It is generally believed that the polar end attaches itself to the filler particle whilst the aliphatic hydrocarbon end is compatible with the rubbery matrix. In a similar manner clays have been treated with amines. 

Leadley and Watts used monochromaticized A1K radiation to investigate the interactions that were responsible for adhesion between polymers and substrates [24]. When polymethylmethacrylate (PMMA) was adsorbed onto silicon substrates, the C(ls) spectrum shown in Fig. 21a was obtained. Originally, it was... 

Wu S., Interfacial energy, structure and adhesion between polymers. Polymer Blends, Vol. 1 (Paul D.R. and Newman S., eds.). Academic Press, New York, 1978. 

Many different silane coupling agents are available for improving the adhesion between polymers and metals or fillers and fibers [1]. Although organofunctional silanes have been reported to be very effective in such adhesion applications, the exact mechanism by which they function has not been determined conclusively in certain cases. Several techniques have been used to characterize silane films formed on various substrates, such as glass, aluminum, and steel. Some of these methods are XPS [2, 3], FUR [4], IETS [5, 6], NMR [7], and Raman spectroscopy [8]. 

The term bioadhesion refers to any bond formed between two biological surfaces or to a bond between a biological and a synthetic surface [44]. In the case of bioadhesive drug delivery systems, the term bioadhesion is typically used to describe the adhesion between polymers, either synthetic... 

The degree of adhesion between polymer chains and filler particles can be evaluated from equilibrium swelling of the composites... 

Polymer surfaces are modified to obtain the desired surface properties without altering the bulk properties (J ). One of the most desired properties is adhesion between polymers and other materials such as polymers, metals or ceramics (2). There are many techniques for polymer surface modification, but they can be divided into two major categories. One is a dry process in which the polymers are modified with vapor-phase reactive species that are... 

Equation 62 is very attractive for the study of adhesion between polymers and sohd surfaces, since it allows for the determination of the viscoelastic constants of the adhesive in the immediate vicinity of the contact. Unfortunately, the QCM does not work well with semi-infinite media when the viscosity, r], is larger than about 50 cP. The bandwidth in this case is too large. Most polymers exceed this limit. If, however, the contact area can be confined to a small spot in the center of the crystal the measurement becomes feasible [74]. Such a small contact area can, for instance, be estabhshed with a JKR tester [75]. The area of contact can be determined by optical microscopy. Of course, this kind of sample is laterally heterogeneous and the apphcabihty of simple models may be questioned. Experiment shows that the finite contact area can be reasonably well accounted for by modifying as ... 

Aix-en-Provence, France RILEM International Symposium, Adhesion between Polymers and Concrete... 

Ohama, Y., Demura, K., Nagao, H., and Ogi, T., Adhesion of Polymer- Modified Mortars to Ordinary Cement Mortar by Different Test Adhesion between Polymers and Concrete Bonding,... 

Conrad, K. H., Adhesion between Polymers and Concrete, pp. 1-5, RILEM International Seminar (ISAP 89), Capri, Italy (May 1989)... 

Before the adhesion between polymers can be discussed, it is essential to clarify what "adhesion means in physical terms. In the simplest approximation, "adhesion" signifies the sticking together of two different materials. From a molecular or microscopic point of view adhesion is related to energetic quantities and is the sum of all intermolecular interactions at the interface. This is what Mittal called "basic adhesion". In macroscopic terms, adhesion... 

Various theories to explain the mechanism of adhesion have been proposed. Most of them deal with the formation of intimate interfacial contact. The problem is that adhesive strength depends not only on the extent of intermolecular interactions at the interface but also on the mechanical response of the materials. This lecture will review some of these theoretical concepts and will close with a discussion of our own investigations of adhesion between polymers. 

The significance of polymer blends has been an incentive for us to take also into consideration the advances in polymer blend preparation. The general characteristics of multicomponent polymeric systems included the formation and transitions of the complex structure in blends crystalline and amorphous components. Since the interactions between the blend components are of great importance the coupling agent activity and the modification of contacts between the components as well as general aspects of adhesion between polymers have been examined. 

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