Poly nanodomains

Papadopoulos, P. etal. Nanodomain-induced chain folding poly(gamma-benzyl-L-glutamate)-b-polyglycine diblock copolymers. Biomacromolecules, 6, 2352, 2005. 

The power law-type spectral dependencies of x and x" are well supported by our experiments. While the unpoled sample exhibits an exponent ft 0.2 (not shown), i. e. large poly-dispersivity, the poled sample yields ft 0.67 for both components of x (Figure 15.14 [58]). Obviously the polydispersivity is largely suppressed at low domain wall densities. This seems to show that polydispersivity is less affected by the nonlinearity in the creep regime, v oc Es, than by the mutual wall interactions in the nanodomain regime [46], Very satisfactorily, also the Cole-Cole plot, Equation (15.21), which is another independent test of the ansatz, Equation (15.18), reveals a very similar exponent, ft 0.69 (Figure 15.15 [58]). 

In another recent report, a thin layer (-200 nm) of homopolymer over BCP film (-80 nm) led to formation of nano-pores (-15 nm diameter) within the films after etching by acetic acid. In this case, small cylindrical nanodomains of poly(methyl methacrylate) (PMMA) are found in polysty-rene-block-PMMA (PS-b-PMMA) when the thickness of the BCP membrane is about 80 nm, which reaches the limit of... 

Fig. 10.8 Example of hierarchical structuration in polystyrene-fc-poly(ethoxy ethyl acrylate) diblock copolymer honeycomb film (AFM topography images). Left hexagonal-pattern of pore Middle zoom of honeycomb film showing diblock copolymer structuration into nanodomains Right SANS curves measured on the deprotected HC film soaked to D2O (from ref. [Ill])...

A schematic picture of the structure of semi-crystalline PODMA is shown in the insets of Fig. 12.1. Basic idea is that the alkyl groups belonging to different monomeric units form layer-like alkyl nanodomains which are separated by main chains. The periodicity dnps of this lamellar structure reflected by the prepeak in x-ray scattering data is indicated. We assume that the alkyl groups within the alkyl nanodomains are basically interdigitated and not to far away from an extended chain conformation. This can be concluded from the dependence of the d ps value on the number of alkyl carbons per side chain C for atactic poly(n-alkyl methacrylates) (Fig. 12.2). The dependence of dnps on (7 is nearly linear and the slope is about 0.13 nm [50] per additional CH2 unit in the side chain corresponding to the value reported for extended chain alkanes (0.127 nm/carbon). 

Nojima S, Ohguma Y, Kadena K, Ishizone T, Iwasaki Y, Yamaguchi K. Crystal orientation of poly(c-caprolactone) homopolymers confined in cylindrical nanodomains. Macromolecules 2010 43 3916-3923. 

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