摘要 |
Polyesters having improved barrier to oxygen are normally solid, thermoplastic methylol polyesters having backbone repeating units containing pendant hydroxyl and methylol moieties and divalent organic moieties such as m-phenylene, p-phenylene, and isopropylidene diphenylene. Such polyesters are prepared by reacting diglycidyl esters of aromatic diacids such as diglycidyl terephthalate or diglycidyl ethers of dihydric phenols with diacids such as isophthalic acid. |