Interface Interfacial compatibility

A. Shindo, Chemical Property of Carbon Fiber Surface and Interfacial Compatibility of Composites, Proc. 1st Int. Conf. Composite Interfaces, North Holland, NY, 1986, pp. 93-100. 

Shindo A, Chemical property of carbon fiber surface and interfacial compatibility of composites, Ishida H, Koenig JL, eds.. Composite Interfaces, North Holland, New York, 93, 1986. 

Interfaces between compatible polymers were also considered, " in an attempt to study the broadening of interfacial profiles with time due to interdiffusion (Fig. 7.22). While the existing work based on Monte Carlo simulations of the bond fluctuation models proves the feasibility of such simulations, which are desirable since they mimic the experimental proce-... 

Compatibility and various other properties such as morphology, crystalline behavior, structure, mechanical properties of natural rubber-polyethylene blends were investigated by Qin et al. [39]. Polyethylene-b-polyiso-prene acts as a successful compatibilizer here. Mechanical properties of the blends were improved upon the addition of the block copolymer (Table 12). The copolymer locates at the interface, and, thus, reduces the interfacial tension that is reflected in the mechanical properties. As the amount of graft copolymer increases, tensile strength and elongation at break increase and reach a leveling off. 

Most recently, significant research efforts have been focused on materials compatibility and adhesion at the zeoHte/polymer interface of the mixed-matrix membranes in order to achieve enhanced separation property relative to their corresponding polymer membranes. Modification of the surface of the zeolite particles or modification of the polymer chains to improve the interfacial adhesion provide new opportunity for making successful zeolite/polymer mixed-matrix membranes with significantly improved separation performance. 

The grafting of polymers to substrates has been studied for over fifty years and remains an important goal in polymer science. Recent work has focused on the synthesis of so-called polymer brushes whereby the polymer chains stretch out away from the substrate or interface [1-5]. This contemporary topic is a direct descendent of earlier work on organic graft copolymers in industry and academia. Research in this area is driven by the need to control the interfacial properties of films and the compatibility of blends. 

It is a common phenomenon that the intercalated-exfoliated clay coexists in the bulk and in the interface of a blend. Previous studies of polymer blend-clay systems usually show that the clay resides either at the interface [81] or in the bulk [82]. The simultaneous existence of clay layers in the interface and bulk allows two functions to be attributed to the nanoclay particles one as a compatibilizer because the clays are being accumulated at the interface, and the other as a nanofiller that can reinforce the rubber polymer and subsequently improve the mechanical properties of the compound. The firm existence of the exfoliated clay layers and an interconnected chain-like structure at the interface of CR and EPDM (as evident from Fig. 42a, b) surely affects the interfacial energy between CR and EPDM, and these arrangements seem to enhance the compatibility between the two rubbers. 

Interfaces are not only present in blends, but are also a key feature of structural joints, where it is often necessary to produce interfacial strengths comparable with the cohesive strength of the bulk materials, and of laminates, where a more modest degree of adhesion may suffice [166]. The compatibility between different components can be expressed in terms of the equilibrium interfacial thickness, w, given approximately by ... 

The response reaction of the host to a foreign material remaining in the body for an extended period of time is a concern. Thus, any polymeric material to be integrated into such a delicate system as the human body must be biocompatible. Biocompatibility is defined as the ability of a material to perform with an appropriate host response in a specific application [79]. The concept include all aspects of the interfacial reaction between a material and body tissues initial events at the interface, material changes over time, and the fate of its degradation products. To be considered bio compatible, a biodegradable polymer must meet a number of requirements, given in Table 2. 

PVA can lower the surface tension of water, reduce interfacial tension at an oil/water interface and enhance tear film stability. These together with ease of sterilization, compatibility with a range of ophthalmic dmgs and an apparent lack of epithelial toxicity have led to the widespread use of PVA as a drag delivery vehicle and a component of artificial tear preparations. 

The complexity and diversity of structures in the native proteins eluded any attempt to produce some simple conformation that accounted for their interfacial properties. The study of synthetic polypeptides with non-polar side chains has provided good evidence to support the view that the a-helix can be stable at the air-water interface (5), and it is therefore possible that the interfacial denaturation of proteins is mainly a loss of the tertiary structure (6, 7, 8). Since for a typical protein an a-helix takes up about the same area per residue as the p conformation, it can be accommodated as easily. Moreover, like the p conformation but unlike a more randomly coiled structure, it is linear and therefore compatible with a plane surface without loss of configurational entropy (5). In this respect a plane surface may favor an ordered over a more random structure. The loss of solubility of the spread protein can then be attributed to intermolecular association between hydrophobic side chains exposed as a result of the action of the interface on the polar exterior of the molecules. 

The tension that exists between two liquid phases is called the interfacial tension. It is a measure of the energy or work required to increase the surface area of the liquid-liquid interface, and it affects the size of dispersed drops. Its value, in units of force per unit length or energy per unit area, reflects the compatibility of the two liquids. Systems that have low compatibility (low mutual solubility) exhibit high interfacial tension. Such a system tends to form relatively large dispersed drops and low interfacial area to minimize contact between the phases. Systems that are more compatible (with higher mutual solubility) exhibit lower interfacial tension and more easily form small dispersed droplets. 

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