Glass fibers surface finish coating

This discussion of chemical stability refers to bare (uncoated) glass fibers, i.e., fibers having neither a specific acid or alkali resistant finish nor a secondary coating. Accordingly, the relationship between fiber composition and chemical stability in water, acids, and bases is complex. It depends on the interaction between (1) the chemical agent [27] to which the glass fiber surface is exposed, (2) foe pH of the glass composition [33] in the fiber surface, and (3) the internal microstructure of foe fiber [27]. 

Fig. 5.82 SEM images show the morphology of surface finish coated glass fibers. The finish is seen in several morphologies as a thin film coating on the surfaces, as lumps of material on the surfaces and connecting fibers, and as etchings or fibrils spanning across the fibers.

Low Temperature [-101 to -1°C (-150 to -l-30°F)] Cellular glass, glass fiber, polyurethane foam, and polystyrene foam are frequently used for this service range. A vapor-retarder finish with a perm rating less than 0.02 is required. In addition, it is good practice to coat all contact surfaces of the insulation with a vapor-retardant mastic to prevent moisture migration when the finish is damaged or is not properly maintained. Closed-cell insulation should not be relied... 

This refers to an open mold technique used for the production of many articles where the resin and reinforcement systems can be tailored to meet specific end use requirements. Typical products produced by this method are skis, boat hulls, tubs, and shower stalls. The molded cavity is sprayed with a gel coat to a desired thickness to produce a desired surface finish or color. The reinforcement, which is usually glass fibers, mats, or sheets, is then hand rolled to secure proper wetting of the fibers as well as the required wall thickness. The final curing takes place through the use of a catalyst or hardener reaction. Matched metal molds are often used with hand lay-up formulations in order to achieve high quality surface finishes on both sides of the molded article. 

An air knife can be used to spread a carbon fiber tow and form a thin veil of carbon fiber or tissue, which can be used to hold a resin rich gel coat on the surface of a fiberglass laminate construction to give a high surface finish concurrent with added microcrack suppression, as well as provide additional chemical resistance. It will give better performance than a glass tissue due to the absence of wicking. 

The process consists of a thin, unreinforced outer coat called a gel coat. The reinforcement (normally glass fibers) mixed with resin (usually polyester) is then applied by hand (lay-up) or via a spray gun (spray-up). When the desired amount of resin and reinforcement is in the mold, the air bubbles are pressed out with a roller. The part is then left to set up which, depending on the size of the part and the amount of resin, can take more than an hour. Consequently, many molds are used when higher production volumes are required. The molds themselves are made of plastic cast from a pattern. As such, they have a very short life and must be replaced frequently. Fortunately, they are inexpensive imfortunately, they are not capable of producing fine detail or close tolerances. Since the mold has only one side, only that side of the part has a finished surface the other side is very rough. The... 

Glass fibers also come in surface veil configuration. These veils are lightweight fiberglass reinforcement mats, customarily used to provide extra environmental protection and a smooth appearance, especially when used in conjunction with gel-coats (a special resin used to provide a high-quality finish on the visible surface of a fiber-reinforced composite material). 

Hazardous Decomp. Prods. Heated to decomp., emits toxic fumes of CL Uses Plasticizer for surface coatings adhesive for composites, metals, glass, ceramics casting metal-forming tools and dies encapsulation of elec, parts cements and mortars rigid foams fiberglass-reinforced plastics elec, dip coats varnishes fiber finishes industrial textile applies. stabilizer, modifier for other resins biomaterial for pharma-... 

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