FRP vs. Fiberglass
“Fiberglass” and “Fiber-reinforced polymer (FRP)” are used interchangeably by many professionals. With two referring to distinct products, both differ technically. Below, we highlight the what fiberglass and FRP are and how they differ.
What Is FRP?
Fibre-reinforced plastic (FRP; also called fiber-reinforced polymer, or fiber-reinforced plastic) is a composite material made of a polymer matrix reinforced with fibres. The fibres are usually glass (in fibreglass), carbon (in carbon fiber reinforced polymer), aramid, or basalt. Rarely, other fibres such as paper, wood, or asbestos have been used. The polymer is usually an epoxy, vinyl ester, or polyester thermosetting plastic, though phenol formaldehyde resins are still in use.
FRPs are commonly used in the aerospace, automotive, marine, and construction industries.
A polymer is generally manufactured by step-growth polymerization or addition polymerization. When combined with various agents to enhance or in any way alter the material properties of polymers, the result is referred to as a plastic. Composite plastics refers to those types of plastics that result from bonding two or more homogeneous materials with different material properties to derive a final product with certain desired material and mechanical properties. Fibre-reinforced plastics are a category of composite plastics that specifically use fibre materials to mechanically enhance the strength and elasticity of plastics.
The original plastic material without fibre reinforcement is known as the matrix or binding agent. The matrix is a tough but relatively weak plastic that is reinforced by stronger stiffer reinforcing filaments or fibres. The extent that strength and elasticity are enhanced in a fibre-reinforced plastic depends on the mechanical properties of both the fibre and matrix, their volume relative to one another, and the fibre length and orientation within the matrix. Reinforcement of the matrix occurs by definition when the FRP material exhibits increased strength or elasticity relative to the strength and elasticity of the matrix alone
Fiberglass is the reinforcement of choice for most FRP products due to it having the best combination of properties and cost. Some companies and countries refer to glass fiber-reinforced polymers (GFRP) to provide the distinction with carbon reinforcements (CFRP.).
What Is Fiberglass?
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.
What’s the Difference Between Fiberglass and FRP?
We can conclude that fiberglass and FRP can be used interchangeably in most, but not all cases. When discussing a composite material, fiberglass means a glass fiber-reinforced polymer (FRP or GFRP.) A fiberglass composite that does not use polymer as the base material cannot be called an FRP composite. Similarly, an FRP composite that does not use glass fibers as the reinforcement material or polymer as the base material cannot be called a GFRP composite.