Adhesion promoters applications

Adhesion promoter. Epoxy silane can be added to increase adhesion to glass (mainly for BR sealants). In certain textile applications, isocyanates can be added to solvent-borne BR cements. 

Hayes, R.A. and Ralston, J., Application of atomic force microscopy in fundamental adhesion studies. In Mittal, K.L. and Pizzi, A. (Eds.), Adhesion Promotion Techniques — Technological Applications. Dekker, New York, 1999, pp. 121-138. 

It appears that both the Hitachi and DuPont polyimide films, when cured, significantly impede the drift of sodium ions at normal device operating temperatures. There is, however, evidence that underlying device oxides can be contaminated by sodium and/or moisture or other polar molecules during the application and curing of the polyimide films. Qeaner resins and adequate device stabilization may control this problem. Further work will be required to characterize contamination levels associated with specific aspects of the processing, such as the adhesion promoter and the polyimide resins themselves. 

Patterns of ordered molecular islands surrounded by disordered molecules are common in Langmuir layers, where even in zero surface pressure molecules self-organize at the air—water interface. The difference between the two systems is that in SAMs of trichlorosilanes the island is comprised of polymerized surfactants, and therefore the mobility of individual molecules is restricted. This lack of mobility is probably the principal reason why SAMs of alkyltrichlorosilanes are less ordered than, for example, fatty acids on AgO, or thiols on gold. The coupling of polymerization and surface anchoring is a primary source of the reproducibility problems. Small differences in water content and in surface Si—OH group concentration may result in a significant difference in monolayer quality. Alkyl silanes remain, however, ideal materials for surface modification and functionalization applications, eg, as adhesion promoters (166—168) and boundary lubricants (169—171). 

Formulation. Polysulfide-based sealants are formulated with appropriate ingredients to obtain the desired properties for a particular application. A typical formulation contains liquid polysulfide polymer, curing agent, cure accelerators (bases) or retarders (acids), fillers, plasticizers, thixotropes, and adhesion promoters. 

Another market application for naphthenic acid is the lire industry, where cobalt naphthenate is used as an adhesion promoter. Naphthenic acid esters have been repeatedly cited as surfactants, lubricants, and replacements for phthalates as plasticizers for PVC resins. 

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