Fiberglass, or “Glass Fiber”, is much like Kleenex, a Thermos or a Dumpster in that a trademarked name has become so familiar that people usually only think of one thing when they hear it. As a Kleenex is a tissue or a Dumpster is a trash bin, Fiberglass is the fluffy, pink insulation that lines the attics of people’s homes, right?
Actually, that’s only a part of the story. The Owens Corning company did trademark the widely used insulation product known as Fiberglas. But, fiberglass itself has a familiar base structure and a wide variety of uses.
Fiberglass really is made of glass, similar to windows or the drinking glasses in the kitchen. The glass is heated until it is molten, then it is forced through superfine holes, creating glass filaments that are very thin – so thin they are better measured in microns. These threads can then be woven into larger swatches of material, or left in the somewhat less structured although more familiar puffy substance used for insulation or soundproofing. This will depend on whether the extruded strands were made longer or shorter, and the quality of the fiberglass. For some applications, it is important for the glass fibers to have fewer impurities, which involves additional steps in the manufacturing process.
Manufacturing With Fiberglass
Different resins may then be added to fiberglass once it is woven together to give it added strength, as well as allow it to be molded into various shapes. Common items made of fiberglass include swimming pools and spas, doors, surfboards, sporting equipment, boat hulls and a wide array of exterior automobile parts. The light yet durable nature of fiberglass also makes it ideal for more delicate applications, such as in circuit boards.
Fiberglass may be mass-produced in mats or sheets or custom-made for a specific purpose. A new bumper or fender on an automobile, for example, may need to be custom-made to replace a damaged area, or for the production of a new model. For this, one would create a form in the desired shape out of foam or some other material, then layer a fiberglass coated in resin over it. The fiberglass will harden, then can be reinforced with more layers, or reinforced from within. But, for items like shingles, a massive sheet of a fiberglass and resin compound may be manufactured and cut by machine.
It should be noted that fiberglass is not carbon fiber, nor is it glass-reinforced plastic, although it is similar to both. Carbon fiber, which is made of strands of carbon, cannot be extruded into strands as long as fiberglass, as it will break. This, among other reasons, makes fiberglass cheaper to manufacture, although it is not as strong. Glass-reinforced plastic is what it sounds like – plastic with fiberglass embedded into it to increase strength. The similarities to fiberglass are apparent, but a defining characteristic of fiberglass is that the glass strands are the main component.
Although there has not been much advancement in the recycling of fiberglass items once they have already been produced, fiberglass itself may be manufactured from recycled glass, and is often done so. Owens Corning has reported the production of fiberglass insulation with as much as 70% recycled glass.