Morphology of block copolymer

The majority of polymers are immiscible and, in bulk, they phase separate to form domains of varying sizes and shapes, depending on their relative volume fraction. This happens because of the very low entropy of mixing in the case of large polymeric molecules. Therefore, unless there is a large favorable enthalpic contribution, most polymers do not form molecularly miscible systems. The same is true for block copolymers, in which the length of each block exceeds a certain critical value. As mentioned earlier, block copolymers are systems wherein two (or more) different types of homopolymers are linked to each other at the chain end(s) diblock copolymers, represented as (A) -(B) , are systems in which two homopolymers are linked to each other at one end, while triblock copolymers, represented as (A)m-(B) -(C)p, are systems in which one central homopolymer block is linked at either end with two other homopolymers. The values m, n and p, represent the 

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Abstract This chapter gives an overview of the research on the self-assembly of amorphous block copolymers at different levels of hierarchy. Besides the influence of composition and topology on the morphologies of block copolymers with linear, cyclic and branched topologies blends of block copolymers with low molecular weight components, other polymers or block copolymers and nanoparticles will also be presented. 

The phase morphology of block copolymers can also be visualized by transmission electron microscopy. Figure 10.8 shows the lamellar structure of Fluoro-PSB-IX. From diblock copolymers it is well known that the resulting microphase morphology depends on the volume fraction (< >) of the two phases. By simple adjustment of the relative block lengths we are able to synthesize block copolymers with specific structures.1718... 

Jiang S, Gopfert A, Abetz V. Novel morphologies of block copolymer blends via hydrogen bonding. Macromolecules 2003 31 6171-6177. 

Ryan, A. J. and Hamley, 1. W. (1997). Morphology of block copolymers. In The physics of glassy polymers, (ed. R. N. Haward and R. J. Young). Chapman and Hall, London. Tuzar, Z. and Kratochvil, P. (1976). Block and graft copolymer micelles in solution. Advances in Colloid and Interface Science, 6,201. 

A review of the thermodynamics of block copolymer melts prior to the discovery of complex phases was presented by Bates and Fredrickson (1990). Ryan and Hamley (1997) have recently reviewed the morphology of block copolymers containing a glassy component, in the melt and glassy states, and a discussion of complex phases is included. Fredrickson and Bates (1996) and Colby (1996) have reviewed the dynamics of block copolymer melts, of which the former is a par-... 

Hasegawa, H. and Hashimoto, T. (1996). Self-assembly and morphology of block copolymer systems. In Comprehensive polymer science. Suppl. 2, (ed. S. L. Aggarwal and S. Russo), p. 497. Pergamon, London. 

Londono, J. D. Dharmapurikar, R. Cochran, H. D. Wignall, G. D. McClain, J. B. Betts, D. E. Canelas, D. A. DeSimone, J. M. Samulski, E. T. Chillura-Martino, D. Triolo, R. The Morphology of Block Copolymer Micelles in Supercritical Carbon Dioxide by Small-Angle Neutron and X-ray Scattering. 

We shall recall the principal theories dealing with the microphase separation and the morphology of block copolymers, but very briefly as they have been recently reviewed in details by Folkes and Keller36. ... 

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