Pauci-chain polystyrene (PCPS) particles, each containing a few polystyrene chains, were prepared by microemulsion polymerization using a chemical initiator. Laser light scattering (LLS), including the angular dependence of the absolute integrated scattered intensity (static LLS) and of the Line-width distribution (dynamic LLS), together with fluorescence, positron annihilation Lifetime. spectroscopy (PALS), and porosimetry, was used to characterize PCPS both in dispersion and as PCPS glasses. The fluorescence spectra showed that similar to 1% of monomer styrene exists in the PCPS. The LLS results suggest that, on average, one PCPS particle prepared using chemical initiator was composed of only similar to 6 PS chains confined to the very small volume of the particle (similar to 1000 nm(3)). PALS studies showed that the average radius of the free volume cavities inside PCPS is larger than that found in conventional PS latex or Bulk PS. The density of PCPS (0.95 g/cm(3)) obtained from porosimetry is 9.5% lower than both that of conventional PS latex and bulk PS (1.05 g/cm(3)). The density and PALS free volume results suggest that the average intermolecular distance between the segments of the many different interpenetrating polymer chains in bulk or conventional latex PS is smaller than that in PCPS, even though the PS chains in PCPS were confined to a very small volume. This implies that the intersegmental approach inside PCPS was more difficult than that inside a conventional PS latex or bulk PS.