Fiberglass: History, Characteristics, Types, Forms, and Properties
Fiberglass, a composite material made of woven glass fibers bound together by resin, has gained remarkable recognition due to its distinctive qualities. It is the top choice in industries ranging from construction to aerospace for its durability, resistance to corrosion, and lightweight properties.
This article explores the history, key traits, different types, various forms, and exceptional properties of fiberglass. Read on to find out more about this material.
What Is Fiberglass?
Fiberglass, otherwise known as glass-reinforced plastic (GRP) or glass-fiber-reinforced plastic (GFRP), is a composite material made from extremely fine fibers of glass. These glass fibers are typically woven into a fabric-like mat or used as a reinforcement material in a plastic resin matrix. The resulting composite material combines the strength and durability of glass with the flexibility and moldability of plastic.
What Is the History of Fiberglass?
The history of fiberglass begins with ancient civilizations like the Phoenicians and Egyptians, who first experimented with glass fibers for decorative purposes. However, these early endeavors were limited in scope, producing only coarse fibers, and the true potential of fiberglass remained unrealized.
Fast forward to the late 19th century; John Player developed a revolutionary process for mass-producing glass strands, primarily for insulation. In 1880, Herman Hammesfahr received a patent for fiberglass cloth interwoven with silk, making it both durable and flame-retardant. These developments laid the foundation for future innovations.
In the 1930s, a chance discovery in Toledo, Ohio, changed the trajectory of fiberglass history. Dale Kleist, a researcher at Owens-Illinois, accidentally created a shower of fine glass fibers while attempting to weld glass blocks. Recognizing the potential of this accidental discovery, engineers refined the process of producing glass fibers efficiently and inexpensively, patenting it in 1933. This marked a crucial turning point, with the first commercially successful glass fiber product—an air filter—hitting the market in 1932.
What Is the Other Term for Fiberglass?
Fiberglass is also called: GRP, short for glass-reinforced plastic or polyester; FRP, which stands for fiber-reinforced plastic; or glass-fiber reinforced plastic (GFRP). The terminology used depends on the location and the industry or sector that uses it.
How Is Fiberglass Made?
The manufacturing process of fiberglass starts with the careful selection and preparation of raw materials, including: limestone, silica sand, soda ash, and various additives like borax, magnesite, nepheline syenite, feldspar, kaolin clay, and alumina. Waste glass, or cullet, can also be used as raw material. These materials are meticulously measured and mixed together—a step known as batching—before it is introduced into a furnace. The furnace is crucial for melting these raw materials into molten glass, with temperatures reaching around 1,371 °C (2,500 °F). Precise temperature control is maintained to ensure a smooth and continuous flow of molten glass.
The molten glass is directed to various forming processes depending on the desired fiberglass type. Various processes can be used to create fibers, including the direct melt process in which molten glass is formed into fibers straight from the furnace, or the use of glass marbles of roughly 1.6 cm (0.62 in.) in diameter that allows visual inspection for impurities. Examples of these processes include passing molten glass through bushings that are electrically heated and have very small orifices, resulting in fine filaments. A continuous filament process involves winding the filaments at high speed to produce long, continuous fibers. A staple-fiber process rapidly cools the filaments with jets of air, breaking them into shorter lengths. Chopped fiber can be obtained by cutting the long-staple strand into shorter lengths.
What Is the Typical Duration Required to Manufacture Fiberglass?
There is no exact duration required to manufacture fiberglass. The time it will take depends on different factors like: the desired fiberglass type, specific product or application, product complexity, the manufacturing process used, the scale of production, curing time, automation, and finishing operations. Some simple fiberglass products may be manufactured in a matter of hours or days, while more complex items may take several weeks or even months to complete. The specific timeline for a fiberglass manufacturing project should be discussed with a manufacturer, as it depends on the product's unique characteristics and the production facility's capabilities.
What Is the Importance of Fiberglass in the Manufacturing Industry?
The importance of fiberglass in the manufacturing industry lies in its unique blend of properties. Not only is it lightweight, but it is also stronger than most traditional materials. Besides this, it can withstand harsh conditions without warping and buckling. This is why it is implemented in such a wide range of applications, from construction and pool and bath manufacturing to printed circuit boards and sporting equipment..
What Are the Characteristics of Fiberglass?
The main characteristics of fiberglass are as follows:
- Durable and strong.
- Fire resistant.
- Excellent insulation material.
- Exceptional chemical resistance.
- High corrosion resistance.
- Dimensionally stable material.
- Insensitive to temperature and humidity changes.
- Resists warping, bending, distortion, or shrinking.
- Moisture resistant.
What Is the Color of Fiberglass?
Fiberglass itself is typically whitish, almost colorless, or transparent in color. However, it can be manufactured and coated in various colors depending on the specific application and requirements. The color of fiberglass products can range from white or gray to black or other custom colors, depending on the additives, coatings, or dyes used during the manufacturing process. PTFE-coated fiberglass fabrics, tapes, and belts are commonly tan in color, often referred to as "natural" within the industry.
What Does Fiberglass Look Like?
Fiberglass typically appears as a fine, thread-like material made of glass. It can be in the form of filaments, mats, or woven fabrics, depending on its intended use. The color of fiberglass can vary but is often white or translucent. It may also be coated or treated with other materials, which can affect its appearance. Overall, fiberglass has a fibrous and somewhat translucent appearance (see Figure 1 below):
Fiberglass, or “glass fiber,” much like Kleenex, Thermos—or even Dumpster—is a trademarked name that has become so familiar that people usually only think of one thing when they hear it: Kleenex is a tissue; a Dumpster is an oversized trash bin, and Fiberglass is that fluffy, pink insulation that lines the attic of your house, right? Actually, that’s only a part of the story. While the Owens Corning Company did trademark the near-ubiquitous insulation product known as Fiberglass, fiberglass itself has a familiar base structure and a wide variety of uses.
How Fiberglass is Made
Fiberglass really is made of glass similar to that in windows or kitchen drinking glasses. To manufacture fiberglass, glass is heated until molten, then forced through superfine holes. This creates glass filaments that are extremely thin—so thin, in fact, that they're best measured in microns.
These flexible filament threads can be used in several applications: They can be woven into larger swatches of material or left in a somewhat less structured form used for the more familiar puffy texture used for insulation or soundproofing. The final application is dependent on the length of the extruded strands (longer or shorter) and the quality of the fiberglass. For some applications, it's important that the glass fibers have fewer impurities, however, this involves additional steps in the manufacturing process.
Manufacturing With Fiberglass
Once the fiberglass is woven together, different resins may be added to give the product increased 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. Having a light yet durable nature, fiberglass is also ideal for more delicate applications, such as in circuit boards.
Fiberglass can be mass-produced in mats or sheets. For instance, for items such as shingles, a massive sheet of a fiberglass and resin compound is manufactured and then cut by machine. Fiberglass also has numerous custom-made applications designed to suit a specific purpose. For example, car bumpers and fenders must sometimes be custom-made, either to replace damaged components for existing automobiles or in the production of new prototype models.
The first step in manufacturing a custom-made fiberglass bumper or fender is creating a form in the desired shape out of foam or some other material. When the form is complete, it's coated with a layer of fiberglass resin. Once the fiberglass hardens, it's subsequently reinforced—either with additional layers of fiberglass or structurally from within.
Carbon Fiber and Glass-Reinforced Plastic vs. Fiberglass
It should be noted that although it's similar to both, fiberglass is not carbon fiber, nor is it glass-reinforced plastic. Carbon fiber is made of strands of carbon. Though extremely strong and durable, carbon fiber cannot be extruded into strands as long as those of fiberglass because it breaks. This is one of several reasons that fiberglass, while it's not as strong, is cheaper to manufacture than carbon fiber.
Glass-reinforced plastic is just what it sounds like: plastic with fiberglass embedded in 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. Glass-reinforced plastic is comprised mostly of plastic, so while it's an improvement over plastic alone for strength and durability, it won't hold up as well as fiberglass.
Although there hadn't been much advancement in the recycling of fiberglass items once they'd already been produced, some new innovations in recycling technology and uses for recycled fiberglass products are starting to emerge. One of the most promising is the recycling of outdated wind-turbine blades.
According to Amy Kover, a reporter for GE Reports, General Electric’s in-house news site, while replacing existing blades with more technically advanced ones can increase wind farm performance by as much as 25%, the process creates the inevitable waste. “Crushing a blade yields about 15,000 pounds of fiberglass waste, and the process creates hazardous dust. Given their enormous length, sending them to a landfill whole is out of the question,” she noted.
In 2017, GE teamed up for a recycling initiative with a Seattle-area-based Global Fiberglass Solutions Incorporated (a company that’s been recycling fiberglass since 2008, and has patented a means to recycle old blades into products including manhole covers, building panels, and pallets). In less than a year, GFSI recycled 564 blades for GE and estimated that in the coming years, GE would be able to re-manufacture or reuse up to 50 million pounds of fiberglass waste.
In addition, a great deal of fiberglass itself is currently manufactured from recycled glass. According to the National Waste and Recycling Association's newsletter "Waste360", recyclers are turning broken glass into a viable resource known as cullet (glass that's been crushed and cleaned), which in turn, is being sold to manufacturers of fiberglass insulation. "Owens Corning uses more than one billion pounds of cullet every year for residential, commercial and industrial fiberglass applications," they report. Meanwhile, Owens Corning has stated that as much as 70% of their fiberglass insulation is now manufactured using recycled glass.