Phenolic resin can be used to make exterior plywood.
Phenolic resin is a thermosetting plastic formed by the reaction of a carbon-based alcohol and a chemical called an aldehyde. Formaldehyde is a common raw material for this type of resin, but other related chemicals can be used. The resin is hard, heat resistant and can be mixed with a wide variety of materials for industrial and residential use.
A phenol is an aromatic hydrocarbon, which means that it contains a group of six carbons joined in a circular arrangement. This molecular shape allows the molecule to bind to other molecules at selected locations around the ring. An aldehyde provides a bonding molecule that creates a regular pattern or grid of phenol groups. The reaction is carried out with heat and creates a very strong and stable polymer called a thermosetting plastic. Hydroxybenzene, or C 6 H 6 O, is often called phenol and is a common raw material. Other phenolic compounds can be used, including material separated from the cashew shell.
Antique telephone made of Bakelite®, a phenolic resin.
There are a variety of uses for phenolic resin in commercial and home applications. It can be cured around a fiber or canvas core to create rigid parts used in pump drives, gears, or other heat-resistant applications. If the paper is saturated with this resin, it can create a popular laminate for kitchens and bathrooms. In the early 20th century, the resin was mixed with wood fibers to create Bakelite®, a popular material for oven handles, kitchen appliances, and door and cabinet accents.
In the early 20th century, phenolic resin was mixed with wood fibers to create Bakelite, a popular radio material.
Phenolic resin board is widely used for electronic circuit board in the 21st century. Cured resin is often mixed with small amounts of natural or synthetic fibers to prevent breakage, as the resin can become brittle when cured. The plates do not conduct electricity and resist the heat generated by electronic equipment.
Compressors and pumps can use phenolic components due to their chemical and heat resistance. Uncured resin is a liquid, so custom part shapes can be molded to meet specific requirements. The parts are lightweight and can replace metal in marine or aircraft applications where weight reduction is required.
Fire resistance is an important benefit of phenolic resin because the material chars rather than burns. Charcoal is a reaction in which molecules transform into a carbon structure, instead of burning as ash. Resins that are exposed to extreme heat release very few toxic fumes, making them useful in aircraft and automobile parts. In spacecraft, heat shields and rocket nozzles can be made from phenolic resins, providing a material that wears and resists combustion.
The circular carbon shape of phenols makes the resins useful as adhesives. They form good chemical bonds with a wide variety of materials and create a very stable adhesive bond when cured. These adhesives are widely used for laminated or layered building boards, decorative wall boards, and interior surfaces on transportation equipment.