Epoxy applications

Reactive Polyamide Resins. Reactive polyamide resins are used extensively lu react with epoxy or phenolic resins. The amount used in epoxy applications far exceeds the use with phenolic resins. 

The preparation of surfaces to receive epoxy compounds is as important as the selection of the proper system for bonding. Concrete surfaces must be freshly exposed, free of loose and unsound material and should be at proper surface temperatures at the time of epoxy application. Among the methods for preparation of concrete surfaces are sandblasting, mechanical scarification and acid etching. The same procedures may be followed for preparation of steel surfaces. Temperature conditions for epoxy application should be in the range of 50°F. to 90 f. Temperature conditions v ill also affect pot life of mixed compounds, as well as curing time. 

The precedence for nitrile-epoxy alloys in other epoxy applications suggests that similar compositions in coatings should enhance film properties associated with flexibility, impact resistance and adhesion to metals. The testing scheme employed emphasizes these property features. 

Key words vegetable oil-based epoxy, preparation of epoxy, curing of epoxy, structure-property relationships of epoxy, application of epoxy. 

The acrylate series is marketed under the Nanocryl name. The silica phase consists of surface-modified, synthetic nanospheres with narrow particle size distributions and diameters below 50 nm. Epoxy versions are called Nanopox and recommended for use in fibrous composites for construction and electrical applications, as well as in casting, potting and encapsulation, together with epoxy applications outside the plastics industry, i.e., in coatings and adhesives. 

Commercial applications of Hycar—epoxy resin systems were at one time predominantly, indeed almost exclusively, the domain of the structural adhesives industry. Adaptation of some of these systems and the associative epoxy technology surrounding carboxyl-terminated liquid rubber have produced a growing Hycar-epoxy alloy consumption in epoxy applications other than structural adhesives. 

M-Cure 204 Metallic Diacrylate for Epoxy Applications Curing Methods ... 

One more application area is composite materials where one wants to investigate the 3D structure and/or reaction to external influences. Fig.3a shows a shadow image of a block of composite material. It consists of an epoxy matrix with glass fibers. The reconstructed cross-sections, shown in Fig.3b, clearly show the fiber displacement inside the matrix. The sample can be loaded in situ to investigate the reaction of matrix and fibers to external strain. Also absorption and transmission by liquids can be visualized directly in three-dimensions. This method has been applied to the study of oil absorption in plastic granules and water collection inside artificial plant grounds. 

Applications. Epoxy resias constitute over 90% of the matrix resia material used ia advanced composites. In addition, epoxy resias are used ia all the various fabrication processes that convert resias and reinforcements iato composite articles. Liquid resias ia combiaation, mainly, with amines and anhydride are used for filament winding, resia transfer mol ding, and pultmsion. Parts for aircraft, rocket cases, pipes, rods, tennis rackets, ski poles, golf club shafts, and fishing poles are made by one of these processes with an epoxy resia system. 

In critical applications, cap bolts with grease-filled containers. In some instances, epoxy materials have been used to fill such caps (with limited success). 

For special applications, however, such as for normally humid areas, and contaminated or chemically aggressive locutions, epoxy paints tne con.sidered to be more appropriate. They provide a protective coating which is resistant to chemical fumes, corrosion and temperature. Chlorinated rubber paints, which also fall into the same category of protective paints, may also be used for these areas but, not being temperature resistant, are not preferred to epoxy paints. 

Two wooden beams are butt-jointed using an epoxy adhesive (Fig. A1.3). The adhesive was stirred before application, entraining air bubbles which, under pressure in forming the joint, deform to flat, penny-shaped discs of diameter 2fl = 2 mm. If the beam has the dimensions shown, and epoxy has a fracture toughness of 0.5 MN mT , calculate the maximum load F that the beam can support. Assume K = cT Tra for the disc-shaped bubbles. 

Elevated temperatures are necessary for cure and the chemical resistance of the laminates is inferior to those from unmodified resins. Because of problems in handling, the polyamides have found only limited use with epoxy resins, mainly for coating and adhesive applications. 

LEE, H., and NEVILLE, K., Epoxy Resins in their Application and Technology, McGraw-Hill, New York (1957)... 

In primer formulations for adhesive bonding of metals, the coupling agents that are most frequently used are those based on epoxy and amine functionalities. Aqueous solutions of aminosilanes have been successfully used for obtaining stable adhesive bonds between epoxy and steel [10] and epoxy and titanium [11,12], while epoxy functional silanes are preferable for applications involving aluminum substrates [13,14], A simple solution of % epoxy functional silane in water is currently used for field repairs of military aircraft [15] where phosphoric acid anodization would be extremely difficult to carry out, and performance is deemed quite acceptable. 

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. 

Applications of NBR adhesives can be divided in three groups (1) solely nitrile rubber (2) nitrile rubber/phenolic blends (3) nitrile rubber/epoxy blends. 

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