Adhesion to various substrates

Binders and Resins. The choice of binder is the most important ingredient choice in the formulation process because the binder affects the performance properties of a paint more than any other single ingredient (3). The physical properties of binders required for paints include the abiHty to dry or cure under various ambient conditions, good adhesion to various substrates, abrasion resistance, washabiHty, flexibiHty, water resistance, and ultraviolet light resistance. The balance of these required properties is mosdy dependent on whether the paint is being developed for interior or exterior appHcations. 

Adhesion promoting silanes are often added to improve adhesion to various substrates. As is the case with urethane sealants, silanes with a dual-reactive nature are typically used. Examples of such silanes are mercapto- and epoxy-functional silanes. Organic titanates may also be used. 

The mechanism of adhesion to various substrates has not been fully explained. Brauer Stansbury (1984b) consider that bonding to composite resins occurs by the diffusion of methacrylate polymer chains into the resin. Bonding to base metals is, perhaps, by salt or chelate bridges. Here it is significant that ZOE cements do not bond, so perhaps bonding is due to the action of free EBA on the substrate. The adhesion to porcelain is surprising. Porcelain is inert so that the attachment can hardly be chemical. Also, it would be expected that if a cement adheres to porcelain then it should adhere to untreated enamel and dentine, but this is not so. 

Unfortunately, although EBA cements have been subjected to a considerable amount of development, this work has not been matched by fundamental studies. Thus, the setting reactions, microstructures and molecular structures of these EBA cements are still largely unknown. In addition, the mechanism of adhesion to various substrates has yet to be explained. Such knowledge is a necessary basis for future developments. 

Unlike traditional polyurethanes, diaminosilanes are typically used as adhesion promoters in hybrid sealants to obtain good adhesion to various substrates. 

Most applications of polymers in electronic packaging have a number of common requirements. Most pervasive is the moisture issue, but other important requirements are low dielectric constant, low dielectric losses (dissipation factor), and good adhesion to various substrates and metallizations. With the... 

Styrene butadiene dispersions are generally stabilized with anionic, or anionic and nonionic emulsifiers. Carboxylation (incorporation of a small proportion of unsaturated carboxylic acids) of SB dispersions increases their stability and improves adhesion to various substrates. Almost all SB dispersions used in the coating sector are carboxylated. 

Adhesion Promotion Techniques Technological Applications, edited by K.L. Mittal and A. Pizzi, 1999, 404 pp., Marcel Dekker. Summarizes state-of-the-art techniques for improving adhesion to various substrates. Theories of adhesion and advanced analytical techniques are reviewed. 

PEA is well known for its use in conventional extrusion coating, co-extrusion coating, and extrusion lamination [105]. The beneficial properties of PEA, such as excellent adhesion to various substrates such as foils, paper, and films, can add value to other polymers that require these properties for specific apphcations. PEA/LDPE blends have many industrial uses because of their good mechanical strength, processability, and impact strength. 

Features Good chem. resist. exc. adhesion to various substrates (metal, plastics, masonry, weather paint) films with exc. mech. props., esp. at bw temp. colloidal paiUdes with exc. mechythermal stability compat. with aq. polj ers (pH 7.5-9)... 

Uses Crosslinking agent, adhesion promoter, tlexibilizer, solv/alcohol/ water resist, aid, hardener for solv. and waterborne polymers primer to improve adhesion to various substrates crosslinking agent for hydrocarbon and aq. coaling and latex emulsion systems Features Functions at ambient temp. 

Uses PU coating imparts exc. adhesion to various substrates, incl. PVC formulation of flexible topcoats... 

Uses Polyamide for inks, coalings, adhesives Features Inks fonnulated with this prod, show exc. adhesion to various substrates, good resist, props., gloss Regulatory FDA 21 CFR 175.105,175.300,176.170 Properties Amber solid sol. in a cosolv. system (alcohol and hydrocarbon) sp. gr. 0.970 vise. 21 -27 poise p 60 C) soften, pt. (B R) 100-115 C acid no. 5 max. (mg KOH/g of resin)... 

The following are examples of adhesion to various substrates. The first method is by the direct application of isocyanate as a primer. 

The resins are characterized, after curing, by high chemical and corrosion resistance, gocd mechanical and thermal properties, outstanding adhesion to various substrates, good electrical properties and ability to be processed under a variety of conditions. 

A coating consists of binder (polymer resin), solvent, pigments and filler. Polyurethane resins have a special place among the natural and synthetic binders in the coating industry due to their excellent adhesion to various substrates. Polyurethane paints and varnishes can be classified in several groups ... 

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