Small angle neutron scattering studies of poly(ethylene oxide) in the melt

The neutron scattering from mixtures of deuterated and undeuterated poly(ethylene oxide), (D‐PEO, H‐PEO), in the small angle and intermediate angle region has been measured in the melt. We found no indications of a molecular segregation. The value of molecular weight evaluated agreed with that obtained by other methods. For a sample with a molar mass of 120000 g/mol the radius of gyration 〈 r w 2 〉 1/2 was found to be 13,6 nm, which corresponds to a characteristic ratio of C = 6,9. The form factor of a single chain can be described by the Debye equation for a random coil with the same unperturbed dimensions. Our results are compared with rotational isomeric state calculations and measurements in solvents.