Copolymer microdomains

Keywords Review Patternable Block copolymer Microdomain Orientation Nanofabrication... 

External fields have been widely used to align block copolymer microdomains. This approach relies on the ability to couple an external applied bias field to some molecular or supermolecular feature, and thus achieve directional control over the microdomains. External fields, such as an electric field [61-63], mechanical flow field [53-55], and temperature gradient [60], have been utilized to control the long-range orientation of block copolymers in the bulk state. 

Fig. 4 Schematic representation of control over block copolymer thin film orientation by directional eutectic solidification. The scheme shows control of polystyrene-b-polyethylene (PS-b-PE) block copolymer microdomain orientation through directional crystallization of benzoic acid (BA), (taken from [95])...

The minor phase of block copolymer microdomains are selectively removed by either chemical or physical degradation, thereby generating a defined porosity in crosslinked polymer bulk matrices or thin films... 

Keywords Electric field Block copolymers Microdomain orientation In situ SFM Orientation mechanism... 

Boker A et al (2002) Microscopic mechanisms of electric-field-induced alignment of block copolymer microdomains. Phys Rev Lett 89(13) 135502... 

The first volume contains review articles on electric field-induced effects on block copolymer microdomains (by H. Schoberth, V. Olszowka, K. Schmidt, and A. Boker) on experiments and simulations of the nanopattern evolution in block... 

Figures 4A and 4B are the ultra-thin cross-sections of OsOi+-stained two-stage (styrene//styrene-butadiene) and (styrene-butadiene/ /styrene) latex particles at the stage ratio of 50/50 (LS-10 and LS-11), respectively. Latex samples were mixed with a polymerizable monomer mix of butyl and methyl methacrylates, cured, and microtomed for examination. Figure 4A shows particle cross-sections much smaller than the actual particle size of LS-10. It appears that since the embedding monomer solution was a solvent for polystyrene, the continuous polystyrene phase was dissolved and small S/B copolymer microdomains were left behind. This is further evidence that the second-stage S-B copolymers phase-separated as microdomains within the first-stage polystyrene phase, as shown in Figures 1A and 1A. Figure 4B shows somewhat swollen and deformed particle cross-sections, suggesting that the first-stage cross-linked S-B copolymers were a continuous phase. Indeed, the former (LS-10) behaved like a hard latex, but the latter (LS-11) behaved like a soft latex.

Helfand has presented a general theory of inhomogeneous polymeric systems and has applied it to the interface between immiscible honmpolymers and to block copolymers In order to simplify the problem of the numerical calculation of the microdomain sizes, he has derived from his general theory a narrow interface approximation The values predicted by the simplified theory for the dimensions of the lamellar block copolymer microdomains are in good agreement with the experimental results ... 

Fukunaga, K., Elbs, H., Magerle, R., Krausch, G. Large-scale alignment of ABC block copolymer microdomains via solvent vapor treatment. Macromolecules 33(3), 947-953 (2000)... 

Park, C., De Rosa, C., Thomas, E.L. Large area orientation of block copolymer microdomains in thin films via directional crystallization of a solvent. Macromolecules 34, 2602 (2001)... 

Lithography with a Pattern of Block Copolymer Microdomains as a Positive or Negative Resist... 

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