Polymeric nanostructures

With its proven capabilities to image the structure and nanoscale composition of polymers, AFM can be applied to a sheer unlimited range of problems. Below we show a concise collection of examples that illustrate the power of AMF to analyze essentially nano- or microstmctured polymers and architectures as is in ambient conditions. 

IMAGING POLYMER MORPHOLOGY USING ATOMIC FORCE MICROSCOPY 

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Toyota Technological Institute Advanced Polymeric Nanostructured Materials Engineering Graduate School of Engineering 2-12-1 Hisakata, Tempaku Nagoya 468 8511 Japan... 

Makinen R, Ruokolainen J, Ikkala O, De Moel K, ten Brinke G, De Odorico W, Stamm M. Orientation of supramolecular self-organized polymeric nanostructures by oscillatory shear flow. Macromolecules 2000 33 3441-3446. 

We have carried out the study of the adsorption on surfaces of finite double rosette l3 (DEB)6 assemblies and the polymeric nanostructures [ 13 631, (Figure 4.6)35 by means of atomic force microscopy.36-41... 

Ordered Polymeric Nanostructures at Surfaces Volume Editor Vancso, G. J., Reiter, G. 

Particulate nanostructures Capsular nanostructures Crystalline nanostructures Polymeric nanostructures... 

The standard molecular structural parameters that one would like to control in block copolymer structures, especially in the context of polymeric nanostructures, are the relative size and nature of the blocks. The relative size implies the length of the block (or degree of polymerization, i.e., the number of monomer units contained within the block), while the nature of the block requires a slightly more elaborate description that includes its solubility characteristics, glass transition temperature (Tg), relative chain stiffness, etc. Using standard living polymerization methods, the size of the blocks is readily controlled by the ratio of the monomer concentration to that of the initiator. The relative sizes of the blocks can thus be easily fine-tuned very precisely to date the best control of these parameters in block copolymers is achieved using anionic polymerization. The nature of each block, on the other hand, is controlled by the selection of the monomer for instance, styrene would provide a relatively stiff (hard) block while isoprene would provide a soft one. This is a consequence of the very low Tg of polyisoprene compared to that of polystyrene, which in simplistic terms reflects the relative conformational stiffness of the polymer chain. 

Fig. 15.5. Schematic depiction of the generalized strategy for preparation of polymeric nanostructures via bulk phase-separated block copolymers.

Ordered Polymeric Nanostructures at Surfaces Materials, Chemistry, Formation, Properties, and Applications... 

Zhao Y. 2007a. Azobenzene containing block copolymers. In Nalwa HS, editor. Polymeric Nanostructures and Their Applications. Vol. 2. California American Scientific Pub lisher. pp. 281 309. 

Firstly, electrolyte solvents for the electropolymerization had to be chosen that do not destabilize the styrenic polymer templates. Note that polymeric nanostructures are highly susceptible to plasticization and the slightest swelling of the template by solvent molecules has to be excluded. Simultaneously, the monomers and salts added for better electrolyte conductivity have to be soluble. Importantly, the solvent must be electrochemically stable at the particular deposition potential and be neutral towards the radicals formed during electrosynthesis. 

Designed Block Copolymers for Ordered Polymeric Nanostructures... 

Hadjichristidis, N. and Pispas, S.i Designed Block Copolymers for Ordered Polymeric Nanostructures. Vol. 200, pp. 37-56. 

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