Small-angle neutron scattering from branched epoxide resins

Dilution and polydispersity in branched polymers

“…The result is that the power laws in the two cases (diluted and undiluted sol) are different and this difference is experimentally measurable. Recent experiments by Schmidt and Burchard [8] and Bantle et al [14] agree with the swelling law corresponding to the distribution of sizes in the percolation model. On the other hand, we expect the classical F.S.…”

Fractal analysis of macromolecules

“…This relation was first obtained by Bantle 78 for the conformation of an isolated branched polymer at the Y-point. Calculation in terms of Eqn (20) for D = 4 gives d c = 6, as for the compensated state.…”

“…Let us consider several experimental estimates of various fractal dimensions for polymers with allowance for the above theoretical statements. The index n in Eqn (4) has been determined by smallangle neutron scattering for epoxy polymers; 78 it was found that n = 0.6. It has been suggested 79 that so great a n value is due to the enhanced chain rigidity of epoxy polymers.…”

“…The cluster with chains protruding from it (`interpenetrating' molecules) assumed in this model resembles the well-known cluster used in the Witten ± Sander (WS) model. 77,78 Such a cluster distinguished in a polymer bulk restricted by the radius R w would possess at least two features typical of fractal clusters. One feature is selfsimilarity, caused by the presence of unstable clusters consisting of fewer segments than thermodynamically stable clusters (Fig.…”