Neutron scattering intermediate angle

O Reilly, J. M., Teegarden, D. M. and Wignall, G. D. (1985) Small-angle and intermediate-angle neutron-scattering from stereoregular poly(methyl methacrylate). Macromolecules, 18, 2747-2752. 

There has been a sharp debate for many years on the best description of the real macroconformation. Much experimental research has been carried out on pure polymers using different techniques (225) [small angle and intermediate angle neutron scattering (226), electron microscopy, IR, etc.]. Yoon and Flory (40, 228-231) and Gawrisch et al. (232) held the view that the probability of adjacent reentry in polymeric lamella is rather low (<50%) and does not justify the validity of such a model. The trajectory of the chain extends across numerous lamellae and its macroconformation is not far from that of the random coil. In the view of Keller and co-workers (224, 233-236) the adjacent reentry, although not complete (3 1 with respect to other possibilities) largely prevails. 

Small angle neutron scattering (SANS) [27] shows that the main chain orients parallel to the director. The detailed behaviour of the combined LC polymers is intermediate between that of LC main-chain and LC side-chain polymers. The polymer chain adopts an anisotropy of about 30% in the ne-... 

Small-angle neutron scattering (SANS) studies on melt crystallized linear polyethylene, isotactic polypropylene, and poly(ethylene oxide) have shown that deuteriated molecules in a hydro-chain matrix have the same radius of gyration, and so molecular conformation, as in melt. This is evidently inconsistent with a regular adjacent re-entry folded chain lamellae. Recently Stamm et in comparing the scattering of neutrons at intermediate angles, of... 

A more thorough investigation at intermediate humidity levels is needed. In addition, it is clear that a number of other studies including scattering at larger Q, quantitative investigations of intensities, and a comparison of small-angle neutron and x-ray results are needed to understand the complex structure present in hydrated Nafions. 

---