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Summary: When the effects of physical aging below T g are erased, the rheological response of a series of aliphatic hyperbranched polyesters is Newtonian and the melt viscosity scales roughly linearly with M w at high M w, indicating entanglement to be absent. The rheological behavior is also highly sensitive to the nature of the terminal groups, suggesting the overall behavior to be close to that of an assembly of compact coreshell "particles". There are therefore strong parallels between the physical behavior of the hyperbranched polyesters in question and that of their ideal dendrimer analogues.

Evidence is presented for the composite nature of the solvated (or trapped) electron absorption band in LiCl aqueous glass at 77 K. It is shown that the overall visible absorption spectrum can be deconvoluted into a homogeneously-bleachable 'green' band and a heterogeneously-bleachable 'red' band, whose relative magnitude and absorption band-maxima change with the concentration of electrolyte. From the combined results of time-resolved and steady-state photobleaching experiments, it is concluded that at least two unstable bands are formed during photobleaching (with smaller lifetimes for the band lying further towards the infrared) which then reconverted into the 'green' band with over 40% efficiency.