Segmented copolyether-urethane-ureas

Substrate materials included poly (dimethyl siloxane) (SR) (Silastic Rubber, medical grade, Dow Corning), fluorinated ethylene/propylene copolymer (FEP) (Teflon FEP, Dupont), and a segmented copolyether-urethane-urea (PEUU) based on poly (propylene glycol), methylene bis-4-phenylisocyanate, and ethylenediamine. This PEUU was provided by D. J. Lyman. 

In this chapter we discuss the nature of the interaction of LiBr with several segmented copolyether-urethane-ureas and the morphological changes resulting from these polymer-salt complexes. 

The Effect of Polyether Segment Molecular Weight on the Bulk and Surface Morphologies of Copolyether-Urethane—Ureas... 

Earlier, we reported that complexes of lithium bromide (LiBr) with copolyether-urethane-ureas led to the formation of hydrogels (6). The water absorption curves for these hydrogels indicated the existence of two modes of absorption an initial water absorption that depended on the concentration ratio of LiBr to the urethane-urea segment (hard segment) of the block copolymer, and the water uptake at higher salt concentration which was attributed to the formation of voids in the film. 

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