Polymer/surface interface

W.R. Salaneck. S. Slalsirdm, J.L. Bredas, Conjuyatetl Polymer Surfaces. Interfaces, Cambridge University Press. Cambridge 1996,... 

We provided an overview of combinatorial and high-throughput methods research at NIST, with a focus on tools and application examples that are useful for the examination of polymer surfaces, interfaces and thin films. An examination of this body... 

Karim, A. and S. Kumar Polymer Surfaces, Interfaces and Thin Films, World Scientific Publishing Company, Inc., River Edge, NJ, 1999 Lisenskey, G.C., et al. Electro-Optical Evidence for the Chelate Effect at Semiconductor Surfaces, Science, 840 (May 18. 1990). 

Karim, Alamgir, and Kum ara Sanata. Polymer Surfaces, Interfaces and Thin Films. River Edge, N.J. World Scientific, 2000. 

Karim A, Kumar S (2000) Polymer surfaces, interfaces and thin films. World Scientific, Singapore... 

Steen, M.L., Butoi, C.I. and Fisher, E.R. 2001a. Identification of gas-phase reactive species and chemical mechanisms occurring at plasma-polymer surface interfaces,... 

J. T. Koberstein, Series on Directions in Condensed Matter Physics Polymer Surface, Interfaces and Thin Films, World Scientific Publishing, Singapore, 2000, pp. 115-181. 

Forrest, J.A., Jones, R.A.L. The glass transition and relaxation dynamics in thin polymer films. In Karim, A., Kumar S. (eds.) Polymer Surface Interfaces and Thin Films. World Scientific, Singapore (2000)... 

H. Yu, in Physics of Polymer Surfaces and Interfaces, I. Sanchez ed., Butterworth-Heinemann, 1992, Chapter 12. 

She et al. [128] used rolling contact to estimate the adhesion hysteresis at polymer/oxide interfaces. By plasma oxidation of the cylinders of crosslinked PDMS, silica-like surfaces were generated which could hydrogen bond to PDMS r olecules. In contrast to unmodified surfaces, the adhesion hysteresis was shown to be larger and proportional to the molecular weight of grafted polymer on the substrate. The observed hysteresis was interpreted in terms of the orientation and relaxation of polymer chains known as Lake-Thomas effect. 

Wool [32] has considered the fractal nature of polymer-metal and of polymer-polymer surfaces. He argues that diffusion processes often lead to fractal interfaces. Although the concentration profile varies smoothly with the dimension of depth, the interface, considered in two or three dimensions is extremely rough [72]. Theoretical predictions, supported by practical measurements, suggest that the two-dimensional profile through such a surface is a self-similar fractal, that is one which appears similar at all scales of magnification. Interfaces of this kind can occur in polymer-polymer and in polymer-metal systems. 

The randomization stage refers to the equilibration of the nonequilibrium conformations of the chains near the surfaces and in the case of crack healing and processing, the restoration of the molecular weight distribution and random orientation of chain segments near the interface. The conformational relaxation is of particular importance in the strength development at incompatible interfaces and affects molecular connectivity at polymer-solid interfaces. 

A WBL can also be formed within the silicone phase but near the surface and caused by insufficiently crosslinked adhesive. This may result from an interference of the cure chemistry by species on the surface of substrate. An example where incompatibility between the substrate and the cure system can exist is the moisture cure condensation system. Acetic acid is released during the cure, and for substrates like concrete, the acid may form water-soluble salts at the interface. These salts create a weak boundary layer that will induce failure on exposure to rain. The CDT of polyolefins illustrates the direct effect of surface pretreatment and subsequent formation of a WBL by degradation of the polymer surface [72,73]. 

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