SANS (small-angle neutron scattering) evaluation of the RPA (random phase approximation) theory for binary homopolymer mixtures

Conference · Mon Dec 01 00:00:00 EST 1986

OSTI ID:6653457

Bates, F S; Koehler, W C; Wignall, G D; Fetters, L J

A well characterized binary mixture of normal (protonated) and perdeuterated monodisperse 1,2 polybutenes has been studied by small-angle neutron scattering (SANS). For scattering wavevectors q greater than the inverse radius-of-gyration R/sub g//sup -1/, the SANS intensity is quantitatively predicted by the random phase approximation (RPA) theory of deGennes over all measured values of the segment-segment interaction parameter Chi. In the region (Chi s-Chi)Chi s/sup -1/ > 0.5 the interaction parameter determined using the RPA theory for q > R/sub g//sup -1/ is greater than that calculated from the zero-angle intensity based on an Ornstein-Zernike plot, where Chi s represents the limit of single phase stability. These findings indicate a correlation between the critical fluctuation length xi and R/sub g/ which is not accounted for by the RPA theory.

• Research Organization: Oak Ridge National Lab., TN (USA); Bell Labs., Murray Hill, NJ (USA); Exxon Research and Engineering Co., Annandale, NJ (USA). Corporate Research Science Lab.
• DOE Contract Number: AC05-84OR21400
• OSTI ID: 6653457
• Report Number(s): CONF-861274-1; ON: DE87004253
• Resource Relation: Conference: Symposium on scattering from block copolymers and model systems, Boston, MA, USA, 1 Dec 1986; Other Information: Paper copy only, copy does not permit microfiche production
• Country of Publication: United States
• Language: English

Related Subjects

75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
36 MATERIALS SCIENCE
POLYMERS
STRUCTURE FACTORS
DEUTERATION
NEUTRONS
SMALL ANGLE SCATTERING
BARYONS
CHEMICAL REACTIONS
ELEMENTARY PARTICLES
FERMIONS
HADRONS
NUCLEONS
SCATTERING
656002* - Condensed Matter Physics- General Techniques in Condensed Matter- (1987-)
360601 - Other Materials- Preparation & Manufacture