PF (Phenol Formaldehyde)

Phenol formaldehyde often be shorten by PF adhesive also called as PF glue, its mean a condensation product of formaldehyde and a monohydrate phenol including phenol itself. Phenol formadehide is produce by raw material of phenol and formaldehyde. The reaction need special condition, temperature, katalis and also need a vacuum pressure to expell of water vapor resulted.

Phenolic tannins of vegetable origin consist of both monohydridic and polyhidric molecular structure, it is more appropriate to discuss them in this section than under resorcinol formaldehyde, RF adhesive.

Synthetic Rubber Production

Synthetic rubber, first manufactured in substantial amounts during world war II, was not a replica of natural rubber, but rather, was synthetized from two monomers styrene and butadiene, that were more readily available than isoprene. These and all other monomers used for synthetic rubber are currently obtained from petroleum. Addition of suitable catalysts to the monomers causes them to polymerize, or joint together, to form the necessary long molecules. Polymerization often occurs in soapy water, and the rubber is formed as a latex, like natural rubber in the tree. It is coagulated and baled like natural rubber, and vulcanization is similarly achieved.

Styrene-butadiene rubber (SBR) remains the most important synthetic rubber manufactured. Techniques for direct imitation of rubber (polyisoprene) by polymerizing the isoprene monomer eluded chemists until the 1950s. Synthetic polyisoprene, however, is more expensive to make than is styrene-butadiene rubber and is of greatest interest to those countries, such as the USSR, which aim to be independent of imported rubber, some is also produced in the United States and Europe.