The chemical modification of poly(2,6‐dimethyl‐1,4‐phenylene oxide) (PPO) by electrophilic sulfonylation and acylation of the aromatic structural units has been investigated. A maximum monosubstitution degree of 79.4 has been reached. Higher substitution levels were difficult to achieve because of both a decrease in the remaining position nucleophilicity and steric hindrances. Minor changes in thermal stability and a broadening of the solubility range of substituted PPO compared with the parent PPO have been recorded. Very good permeation properties to gases, better than for PPO, have been detected for the modified structures.
No takes yet. Share an insight, caveat, or question.
Simona Percec (1987) studied this question.
Synapse has enriched 5 closely related papers on similar clinical questions. Consider them for comparative context: