Frank J. Williams

Oligomers and Polymers of Polyethers and Polyformals

Abstract Linear high molecular weight aromatic polyformals are readily obtained from biphenols and excess methylene chloride with solid sodium hydroxide or potassium hydroxide in the presence of a phase transfer catalyst or an aprotic dipolar solvent. By control of the stoichiometry bifunctional oligomers can be obtained which can subsequently be incorporated into a variety of block copolymers.

The Synthesis of Aromatic Polyformals

The synthesis of aliphatic polyformals (1) has been known for many years and is relatively straightforwardl. As shown in equation 1, aliphatic diols can be reacted directly with formaldehyde or dialkyl formals (2) to produce these polymers. The principal complication of the reaction occurs when the diol used contains 2, 3 or 4 carbon atoms in which case the formation of the cyclic formal (3) is favored.