Phenolic plastic (bakelite) properties and uses
Heat resistance: From a practical point of view, the use temperature of phenolic plastics with various fillers is: inorganic filler 160 ℃; organic filler 140 ℃; the maximum use temperature of glass fiber and asbestos filler is 170 ~ 180 ℃.
Corrosion resistance: Machining phenolic resin without fillers is hardly attacked by inorganic acids, insoluble in most hydrocarbons and chlorides, and insoluble in ketones and ethanol. However, it is not resistant to corrosion by concentrated sulfuric acid, nitric acid, high temperature chromic acid, fuming sulfuric acid, alkali and oxidizing agents. Phenolic plastic also has the above-mentioned characteristics, but when studying its corrosion resistance, the corrosion resistance of the filler must also be taken into account.
Modification of phenolic plastics: The main disadvantages of phenolic plastics are brittleness, poor arc resistance, and dielectric properties that change with frequency. Therefore, in production applications, modification methods are used to make up for the shortage of machining bakelite . The use of phenolic resin (mainly thermoplastic) and other types of polymer blending applications can improve the performance of phenolic plastics.
Commonly used polymer compounds are: polyamide resin, polyvinyl chloride resin, nitrile rubber, polypropylene resin and so on. For example, after mixing with polyvinyl chloride, it can improve its mechanical strength, heat resistance, dielectric properties, acid resistance, water resistance, etc., and has good colorability. Bakelite powder based on phenolic resin and nitrile rubber can greatly improve the impact strength of the parts.
Bakelite powder made with a mixture of phenolic resin and polyamide resin and inorganic fillers (such as mica and feldspar) has higher dielectric properties, and its products can be used under high temperature, high frequency and high pressure conditions.
Uses: Widely used as electrical insulation materials, furniture parts, machine tool accessories, mechanical operating parts, valve hand wheels, handles, handles, handles, handles, daily necessities, handicrafts, etc. In addition, it is also used as asbestos phenolic plastic for acid resistance, rubberized paper for insulation, rubberized cloth, phenolic foam for insulation and sound insulation and honeycomb plastic.