Abstract
In this Letter we applied for the first time a small-angle neutron scattering (SANS) extrapolation method to study the influence of nanoparticles (NPs) on polymer chain conformation in polymer nanocomposites (PNCs). This new approach is based on a perfect NP matching thanks to a statistical hydrogenated (H)/ deuterated (D) polymer matrix in which a certain amount of labeled chain (H) is added. The extrapolation to zero H content gives the intrachain structure factor, S1(q), and the interchain correlations, S2(q), the latter not being accessible under the zero average contrast (ZAC) condition preferentially used in the previous studies. We validate the method on well-known silica/polystyrene (PS) PNCs and compare the results with our previous ZAC measurements. The analysis of both S1(q) and S2(q) shows (i) no significant modifications of the radius of gyration Rg of the chain and of the interchain interaction induced by the presence of NPs and more interestingly (ii) the existence of chain domains with lower densities included inside NP clusters as the result of excluded volume effects that create an extra scattering at low q. The extrapolation method unambiguously shows that the unexpected behavior observed at low q comes from the chains and not from the unmatched NPs.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
