Measurement of the Second Virial Coefficient of C60in CS2Solution from Small-Angle Neutron Scattering

Langmuir ◽  
1997 ◽  
Vol 13 (23) ◽  
pp. 6139-6145 ◽  
Author(s):  
Stephen J. Henderson
Keyword(s):  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Virial Coefficient ◽  
Second Virial Coefficient

scholarly journals Structural Characterization of a Polymer Substituted Fullerene (Flagellene) by Small Angle Neutron Scattering

1994 ◽  
Vol 359 ◽  
Author(s):  
K.A. Affholter ◽  
G.J. Bunick ◽  
J.M. Desimone ◽  
M.O. Hunt ◽  
Y.Z. Menceloglu ◽  
...  
Keyword(s):  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Virial Coefficient ◽  
Scattering Length ◽  
Second Virial Coefficient ◽  
Radius Of Gyration ◽  
Polystyrene Sample ◽  
Negative Scattering Length

ABSTRACTSmall-angle neutron scattering (SANS) can structurally characterize fullerenes1in solvents with strong SANS contrast (e.g. CS2). Deuterated solvents (e.g. toluene-d8) have a high scattering length density (SLD), which is close to that of C60and C70moieties. Hence, there is virtually no SANS contrast with the solvent and these particles are practically “invisible” in such media. On the other hand, the negative scattering length of hydrogen means that the SLD of H1-containing materials is much lower, so they have strong contrast with toluene-d8. Thus, SANS makes it possible to study the size and shapes of modified buckyballs such as the polymer-substituted fullerenes, or flagellenes2. These consist of C60cores to which 1-4 polystyrene chains (with a molecular weight, MW ≃ 2000) are attached. The extrapolated cross section at zero angle of scatter [dΣ/dΩ(0)]s is a function of the number of pendant chains, so SANS can be used to assess the number of “arms” which are covalently attached to the fullerene “sphere”. Close agreement (± 4%) between the measured and calculated values of dΣ/dΩ(0) along with independent estimates of the radius of gyration (Rg) and second virial coefficient (A2) for a calibration linear polystyrene sample serves as a cross check on the validity of this methodology.

SANS Studies of Octyl-β-glucoside and Glycine Micellar Solutions

1997 ◽  
Vol 30 (5) ◽  
pp. 761-764 ◽  
Author(s):  
R. Giordano ◽  
G. Maisano ◽  
J. Teixeira
Keyword(s):  
Neutron Scattering ◽  
Detailed Analysis ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Virial Coefficient ◽  
Critical Micellar Concentration ◽  
Steric Interaction ◽  
Micellar Solutions ◽  
High Concentration ◽  
Low Concentration

Small-angle neutron scattering (SANS) experiments were performed on micellar solutions of octyl-β-glucoside (OBG) in water and on solutions of OBG + glycine in water. A detailed analysis of the results obtained for different concentrations (from 0.026 to 1 M) of glycine and OBG shows that: (i) the structure of the micelles of OBG is always ellipsoidal with the long axis increasing as the concentration of OBG increases from the critical micellar concentration (c.m.c. = 0.022 M) to 1 M; (ii) there is a tendency to form aggregates at concentrations of OBG smaller than 0.5 M; (iii) steric repulsive interactions are clearly seen for concentrations above 0.6 M. The virial coefficient is evaluated as a function of the concentration in OBG. The negative values at low concentration reveal the presence of attractive interactions, while at high concentration the repulsive steric interaction dominates. At high concentration of OBG, the spectra with or without glycine are the same. The analysis shows that glycine remains in water and that its presence does not affect the structure of the micelles.

Small-Angle Neutron Scattering Study of Poly(oxyethylene)-block-poly(oxypropylene)-block-poly(oxyethylene) in Aqueous Solutions

1993 ◽  
Vol 58 (10) ◽  
pp. 2428-2436 ◽  
Author(s):  
Herman Pospíšil ◽  
Josef Pleštil ◽  
Zdeněk Tuzar
Keyword(s):  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Structural Parameters ◽  
Second Virial Coefficient ◽  
Scattering Data ◽  
Radius Of Gyration ◽  
Deuterated Water ◽  
Neutron Scattering Study ◽  
Copolymer Poly

Solutions of a triblock copolymer, poly(oxyethylene)-block-poly(oxypropylene)-block-poly(oxyethylene) (POE-POP-POE), in deuterated water were studied by small-angle neutron scattering (SANS) in the temperature range from 20 to 45 °C. Radius of gyration, molecular weight, second virial coefficient for both unimers and micelles, critical micelle concentration and unimer concentration were determined from the scattering data. Under assumption of the spherical core/shell micellar model structural parameters were estimated. Degree of swelling of the micellar core was evaluated from the mean-square fluctuation of scattering density.

Microstructure of die-cast alloys Mg–Zn–Al(–Ca): a study by electron microscopy and small-angle neutron scattering

2003 ◽  
Vol 94 (5) ◽  
pp. 564-571 ◽  
Author(s):  
Michael Vogel ◽  
Oliver Kraft ◽  
Peter Staron ◽  
Helmut Clemens ◽  
Rainer Rauh ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Neutron Scattering ◽  
Small Angle ◽  
Small Angle Neutron Scattering ◽  
Die Cast ◽  
Cast Alloys
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