Screening effects in solutions of a hyperbranched, dendrimer-like polyester

We have previously shown that infrared spectroscopy can be used to "count" the number of contacts in hydrogen-bonded system. We use such information t o determine appropriate self- and interassociation equilibrium constant val ues and at the same time take into account the intramolecular "screening" i n polymer blends and solutions. The calculated values reported here for scr eening, and hence the accessibility of the functional groups in a hyperbran ched polyester, are based on the interassociation equilibrium constants obt ained from the low molecular weight counterparts of the hyperbranched repea t units and give a measure of the accessibility of functional groups in the se highly branched systems.