Light scattering copolymers

Several methods may be applied to obtain the micellar size and shape of block-and-graft copolymers light scattering, small-angle X-ray scattering, small-angle neutron scattering. 

Another example of OTHdC application is the study of the association/ dissociation of copolymer micelles. Using the light-scattering technique, the... 

Brown, W Schillen, K Hvidt, S, Triblock Copolymers in Aqueous Solution Studied by Static and Dynamic Light Scattering and Oscillatory Shear Measurements. Influence of Relative Block Sizes, Journal of Physical Chemistry 96, 038, 1992. 

Branching in the polymer chain affects the relationship between retention and molecular weight.83 Universal calibration has been used with some success in branched polymers, but there are also pitfalls. Viscosimetry84-91 and other instrumental methods have proved to be useful. A computer simulation of the effects of branching on hydrodynamic volume and the detailed effects observable in GPC is available in the literature.92 93 In copolymer analysis, retention may be different for block and random copolymers, so universal calibration may be difficult. However, a UV-VIS detector, followed by a low-angle light-scattering (LALLS) detector and a differential... 

Thus, the results of the studies of poly(NVCl-co-NVIAz) synthesized in an aqueous medium at a temperature above the PST demonstrated that some of the copolymers exhibit typical LCST-properties, whereas other copolymers remain water-soluble upon the heating of their solutions but show the transition effects detected by HS-DSC (as well as by NMR and light scattering, see below). From these data, the following questions can be formulated ... 

However, certain contradictions can be seen from the data of Tables 1 and 2. Indeed, the molecular weights determined for aqueous solutions of these p- and s-fraclions in the SEC experiments (Table 1) coincided well with the results of light scattering for DMSO solutions (Table 2) but why did the molecular weights differ so considerably from the light scattering data (Table 2) for the solutions of given copolymers in pure water, where, in... 

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