Isotope driven critical scattering and phase separation in mixtures of deuterated and protonated polymers

Four separate isotopic polymer mixtures have been examined by SANS: deuterated and protonated atactic polystyrenes, 1,4-polybutadienes, polyvinylethylenes (also referred to as 1,2-polybutadienes), and polyethylethylenes (also known as 1,2-polybutenes). With the exception of the polystyrenes, all polymers were characterized for number average degree of polymerization N{sub N} and polydispersity N{sub W}/N{sub N} by membrane osmometry and high pressure size exclusion chromatography (HPSEC), respectively. SANS data were collected on the 30-m instrument at the National Center for Small- Angle Scattering Research located at Oak Ridge National Laboratory. 29 refs., 4 figs., 1 tab.