Chain extenders bisphenols used

Bisphenol A propoxylated or ethoxylated with 2-10 mols of alkylene oxides/mol of bisphenol A are used as chain extenders for PU elastomers and as aromatic diols for isocyanuric and urethane isocyanuric foams [30] (structure 15.30). 

The nucleophilic displacement polymerization starts with the monomeric bisimides, that are halogen substituted at the aromatic ring. The bisimides are chain extended at the aromatic ring using bisphenols. The process is shown schematically in Figure 15.4. 

In a later study by Dhavalikar and Xanthos [180], the authors investigated di- and tri-functional additives. The diepoxides used were the commercially oriented additives, diglycidyl ether of bisphenol A with molecular weight of approximately 350 (Epon 828) and N,N -bis[3(carbo-2",3 -epoxypropoxy)phenyl]pyromellitimide. Such additives have long been considered to be suitable chain extenders, with their ability to react with carboxyl and hydroxyl end groups ... 

Recently, unsaturated (oligomeric) polyesters (UPE) of molecular weights in the range of 500-700 Da have been chain-extended at temperatures between 130 and 160 °C using di- or multifunctional epoxy compounds.The extenders were bisphenol A diglycidyl ether (5 in Figure 1), 1,2,7,8-diepoxyoctane, and epoxidized soybean oil. Different... 

Applications of MALDI have been extended by exploring some peculiar aspects of the MALDI-TOF response to the phenomenon of molecular association in poly(bisphenol-A carbonate) (PG) samples. Chain self-association was observed when a 10 mg/ml solution was injected onto SEC columns, using... 

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