Phenol formaldehyde (PF) resin is a chemical compound formed when phenol and formaldehyde react together. It is used in many industries because of its strength, versatility, and stability. In the woodworking industry, it is employed as a bonding agent between wood laminates. Also, because it is a thermal insulator, PF is able to withstand high temperatures.
Resins from the PF family are referred to by different terms including phenoplast resin and phenolic resin. Based on the molecular structure of the PF resin, the ratio of phenol to formaldehyde, and the catalyst used to control the reaction, they can be classified into two main types: resole and novolac. This article will further discuss and expand on the subject of phenol formaldehyde resin.
What Is Phenol Formaldehyde Resin?
Phenol formaldehyde resin, or PF, is sometimes referred to as phenolic resin. It is a synthetic polymer created by the reaction of phenol (or a phenol substitute) with formaldehyde. The properties of phenolic resins vary depending on the quantity or ratio of phenol and formaldehyde during the reaction as well as the type of catalyst used. Catalysts can be either acids or bases.
The large networks of molecules that form during the reaction are permanently bonded. PF is quite a useful synthetic polymer. It was the first synthetic resin to be employed commercially, falling under the moniker, Bakelite. Bakelite was an early form of plastic that used to end up in devices such as radios and telephones. Also, PFs come in handy in the manufacturing of laboratory countertops, billiard balls, adhesives, and coatings. For more information, see our guide on 3D Printing Materials.
What Are the Other Terms for Phenol Formaldehyde Resin?
Phenol formaldehyde is not the only name used to describe this synthetic polymer. Other names include: phenolic resin, phenoplast, phenol formaldehyde, and phenolic plastic. In the commercial space, it is sometimes referred to by trade names such as: Novotext, Micarta, and Bakelite. Phenolic resin is popular in the industry thanks to its good dimensional stability, high heat resistance, and good electrical resistance.
There are, however, some drawbacks. The most notable among them is the fact that these resins are surprisingly brittle despite being known for their durability. As a result, phenoplast is often produced with strengthening filler material.
Where Is Phenol Formaldehyde Resin Used?
Phenol formaldehyde resin finds relevance in many industries including: automotive, construction, and woodworking industries. Automotive components such: as brake pads, fuel pumps, and transmission parts are all made with phenolic-based resins. In the woodworking space, phenol formaldehyde is sometimes used in the manufacturing of medium-density fiberboard and particleboard. Those materials find application in furniture making, cabinetry, and flooring products. The function of the resin is to create a strong and durable bond between the wood fibers. The resulting bond is impervious to moisture and insects. Based on the increasing number of uses for PF resin, it will clearly continue to be an important material. It is a valuable resin that is essential to many industrial processes.
What Is the Structure of Phenol Formaldehyde Resin?
The structure of phenol formaldehyde resin is dependent on the ratio of phenol to formaldehyde as well as the type of catalyst present — either an acid or a base. Table 1 below describes two common structures of phenolic resin: