Thus they are soluble and fusible.

Explanation: If the resinification reaction is stopped at early stages, a low molecular weight product soluble in alkalis and alcohol is obtained. It is known as resole or A-stage resin, which has 3-4 aromatic rings and 3-5 methylol groups. It may be either linear or may be lowly branched.

Explanation: The reaction of resols with other reactive species and also among each other leads to the production of B-staged resins, known as resitols, which are mildly cross-linked molecules.

Explanation: Resitols being slightly heat fusible on further heating turn into fully cured or cross-linked resin known as resite or C-staged resin which is totally insoluble and infusible.

Explanation: Caustic soda catalyzed resols are suitable for mechanical and decorative laminates while ammonia catalyzed resols are used for electrical laminates.

Explanation: Compression moulding is operated to mould the phenolic moulding powders by using a pressure of about 1500-3000 psi and temperature of 160-170 ᵒC.

Explanation: The casting grade phenolics are prepared from highly pure grades of phenol and formaldehyde using more than 2 moles of formaldehyde per mole of phenol and employing alkaline catalyst.

Explanation: To minimize color formation, a stainless steel kettle is used in the process of formation and a mild temperature of 70-75 ᵒC is maintained.

Explanation: Due to their attractive colours and transparency, self-lubricating properties and good machinability, the cast phenolics are used as objects of art and jewellery and as handles of tools and umbrella, knobs, etc.

Explanation: The cross-linking of novolacs is better accomplished using a basic catalyst. An insoluble, infusible, cross-linked polymer products is then formed in a single step.