Phase behavior of nanoparticle/diblock copolymer in a selective solvent.

Journal Article · Mon Jan 01 04:00:00 EST 2007 · Macromolecules

DOI:https://doi.org/10.1021/ma061950t· OSTI ID:917986

Lo, C -T; Lee, B; Winans, R E; Thiyagarajan, P

Solvents used for controlling the self-assembly of polymer nanocomposites have a strong influence on the order-disorder and order-order transition temperatures. We have investigated the phase behavior of complexes composed of poly(styrene-b-2-vinylpyridine) (PS-PVP) and thiol-terminated PS stabilized Au nanoparticles in toluene-d (a good solvent for PS) by using small-angle neutron scattering. We observe that the morphologies of the neat and nanoparticle-containing polymer solutions strongly depend on the concentration of nanoparticles and temperature. Comparison of the phase diagrams of the neat and nanoparticle-containing polymer solutions as a function of temperature clearly shows dramatic shifts in the order-disorder and order-order transition temperatures. This dramatic effect can be understood by a model wherein the added nanoparticles that sequester in the preferred PS domains increase the interfacial curvature, leading to the observed changes in the nanostructure of the complex. Some effects are similar to those of the selective solvent such as toluene on the nanostructure of PS-PVP. Knowledge gained from these studies on the effects of nanoparticle concentration and temperature on the phase behavior of the polymer nanocomposites will be valuable for tailoring the physical properties of novel nanocomposites.

• Research Organization: Argonne National Laboratory (ANL)
• Sponsoring Organization: SC
• DOE Contract Number: AC02-06CH11357
• OSTI ID: 917986
• Report Number(s): ANL/XSD/JA-60376
• Journal Information: Macromolecules, Journal Name: Macromolecules Journal Issue: 3 ; 2007 Vol. 40
• Country of Publication: United States
• Language: ENGLISH

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
COPOLYMERS
NANOSTRUCTURES
NEUTRONS
PHASE DIAGRAMS
PHYSICAL PROPERTIES
POLYMERS
SCATTERING
SOLVENTS
TOLUENE
TRANSITION TEMPERATURE