Small‐angle neutron scattering by two‐component particles: Application to block copolymers

Abstract

General equations for small‐angle neutron scattering are derived for block copolymers in dilute solution. The effects of excluded volume and polydispersity are examined. The applicability of the method of variable contrast to such systems is discussed.

Organization of surfactant micelles adsorbed on a polymer molecule in water : a neutron scattering study

“…Similar considerations apply to the apparent radius Rapp which can be deduced from the slope of the CII(Q) vs. Q2 plot [21][22][23][24]. For a solution of particles which all have the same composition, this radius is related to the radius of gyration Rg of a homogeneous particle which would have the same volume by :…”

“…One way to do it is to observe separately the scattering from each component. This requires the use of the contrast matching method [21][22][23][24]. First one should make sure that the 2 components have very different indices of refraction for the radiation used in the experiment.…”

“…with NaBr(0.4 M). Of course the scattered intensities depend on the contrast [21][22][23][24], i.e. on the difference between the average scattering length density of the aggregates p and that of the solvent p..…”

Interpretation of small angle neutron scattering by copolymer solutions as a function of concentration

“…with Rn and a n are respectively the number average radius of gyration and composition [10]. In the numerical calculations we have used the value of the radius of gyration of the copolymer given by the relation :…”

Microphase separation transition of weakly charged copolymers in solution

“…The second term on the rhs of eq 9 is the structure factor one would measure if the increments of the refractive indices of the two blocks are equal but have opposite signs. [8][9][10][11][12][13][14][15][16] In this so-called optical condition or zero average contrast condition, one has 4S,(q) P1/2(q)-P(q) -* =--(Ha) l-|0AT[P1/2(q)-PT(q)] Si(q) represents the static correlations of composition fluctuations, namely if pi(q) is the quantity…”