PHENOLIC RESIN Phenolic Resin - A synthetic resin produced by the condensation of a phenol with an aldehyde (usually formaldehyde). A component of laminated plastics and varnishes for varnished cambric tapes. Plastic - High polymeric substances, including both natural and synthetic products, but excluding the rubbers, that are capable in their manufacture of flowing under heat and pressure. NEMA Grades L and LE are made from linen which has been impregnated with a phenolic resin binder. Canvas based laminates combined with phenolic resin makeup the NEMA C and CE Grades. They are normally stronger than the linen/phenolic laminates, but because of the coarser weave fabric, do not lend themselves to as fine a machined surface as do the linen grades. Phenolic resins are made by the combination of phenols and formaldehyde in the presence of a acid or base catalyst. For structural applications, caustic solutions can be used, but for electrical applications, non-ionic catalysts such are ammonia or aniline are used. In use to make a laminate, phenolic resins sometimes are used as they are and sometimes have additives such as flame-retardants, plasticizers or other chemicals added to enhance the properties. Additional catalysts are not needed, as the phenol/formaldehyde reaction is a condensation reaction and self propagating. |phenolic resin|Phenolic Resins|plastic laminate|composite materials|