Copolymer homopolymer blends

F. S. Bates, W. Maurer, T. Lodge, M. F. Schulz, M. W. Matsen, K. Almdal, K. Mortensen. Isotropic Lifshitz behavior in block copolymer-homopolymer blends. Phys Rev Lett 75 4429-4432, 1995. 

Instead of the familiar sequence of morphologies, a broad multiphase window centred at relatively high concentrations (ca. 50-70% block copolymer) truncates the ordered lamellar regime. At higher epoxy concentrations wormlike micelles and eventually vesicles at the lowest compositions are observed. Worm-like micelles are found over a broad composition range (Fig. 67). This morphology is rare in block copolymer/homopolymer blends [202] but is commonly encountered in the case of surfactant solutions [203] and mixtures of block copolymers with water and other low molecular weight diluents [204,205]. 

Microdomains of block copolymer/ homopolymer blends 25-A-diameter Pd clusters Metal-ion precursors, introduced into cast thin films of polymer microdomains, are reduced by high pressure hydrogen 60,61... 

This chapter is organized as follows. Section 6.2 is concerned with experiments on binary block copolymer/homopolymer blends, Section 6.3 deals with experiments on ternary blends containing a block copolymer and in Section 6.4 experiments on binary blends of block copolymers are reviewed. Theory for the corresponding type of blend is discussed successively in Sections 6.5 to 6.7. Finally, experiments on thin films are discussed in Section 6.8, separately from the work on bulk blends, in keeping with earlier chapters. 

Experiments on binary block copolymer/homopolymer blends... 

Table 6.1 Experimental studies of binary block copolymer/homopolymer blends. Adapted and extended from Roe and Rigby (1987)...

Urbas, A., Fink, Y, and Thomas, E., One-dimensionaUy periodic dielectric reflectors from self-assembled block copolymer-homopolymer blends. Macromolecules, 32, 4748, 1999. 

K. R. Shull (1993) Interfacial phase-transitions in block copolymer homopolymer blends. Macrom,olecules 26, pp. 2346-2360... 

Lee, J.H., Balsara, N.P., Chakraborty, A.K., Krishnamoorti, R. and Hammouda, B. (2002) Thermodynamics and phase behavior of block copolymer/homopolymer blends with attractive and repulsive interactions. Macromolecules, 35, 7748-7757. 

Bates, RS., Maurer, W., Lodge, T.P., Schulz, M.R, Matsen, M.W., Almdal, K. and Mortensen, K. (1995) Isotropic lifshitz behavior in block copolymer-homopolymer blends. Phys. Rev. Lett., 75, 4429-4432. 

Banaszak M, Whitmore MD. Mean field theory of the phase behavior of ternary block copolymer-homopolymer blends. Macromolecules 1992 25 249-260. 

Surface Activity of Block Copolymers. Modification of surface properties of a homopolymer by incorporating a small proportion of block copolymer has been studied for several block copolymer-homopolymer blends. LeGrand... 

Information on the phase diagrams of copolymer/ homopolymer blends can be found in reviews by... 

This brief summary of compatibilizer effects on the flow behavior of polymer blends substantiate that many aspects of the behavior remain unclear. For example, the effects of limited miscibihty of copolymer, the copolymer structure and molecular weight, micelle formations and inter-particle interactions are still beyond the capability of the proposed models. Similarly, little information has been published on copolymer/homopolymer blends. 

Ibarboure, E., Bousquet, A., Toquer, G., Papon, E., Rodriguez-Hemandez, J. Tunable hierarchical assembly on polymer surfaces Combining microphase and macrophase separation in copolymer/homopolymer blends. Langmuir 24(13), 6391-6394 (2008)... 

Phase Separation in Block Copolymer-Homopolymer Blends... 

Winey, K.I., Thomas, E.L., Fetters, L.J. The ordered bicontinuous double-diamond morphology in diblock copolymer/homopolymer blends. Macromolecules 25, 422-428 (1992)... 

Information on the phase diagrams of copolymer/homopolymer blends can be found in reviews by Ajji and Utracki (1996, 1997) and in Chap. 2, Thermodynamics of Polymer Blends in this handbook. The interface thickness of AIA-B mixtures was not theoretically calculated, but experimental measurements indicate that the presence of the homopolymer leaves the domain boundary unchanged (Bates et al. 1983 Hashimoto et al. 1990a Tanaka et al. 1991 Zin and Roe 1984 Green et al. 1989). On the other hand, the part of the phase diagram where the concentration of the block copolymer in the mixture is low was studied in detail (Whitmore and Noolandi 1985 Leibler et al. 1983 Leibler 1988). The proposed models were similar. In both, the conditions for the formation of spherical micelles... 

Floudas et al. (1997) studied theoretically and experimentally microphase segregation in block copolymer/homopolymer blends for an asymmetric diblock copolymer and homopolymer concentrations of less than 25 %. It was observed that the minority phase could solubilize only a small amount of added homopolymer. The addition of higher amounts resulted in the formation of nonequilibrium structures. Theoretical predictions in the strong segregation limit showed that (xN)c,... 

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