Copolymers in solution

In solution-based polymerisation, use of the initiating anionic species allows control over the trans /cis microstmcture of the diene portion of the copolymer. In solution SBR, the alkyUithium catalyst allows the 1,2 content to be changed with certain modifying agents such as ethers or amines. The use of anionic initiators to control the molecular weight, molecular weight distribution, and the microstmcture of the copolymer has been reviewed (15). 

Tuzar Z, Kratochvil P (1993) Micelles of block and graft copolymers in solution. In Matijevic E (ed) Surface and colloid science, vol 15. Plenum, New York... 

Zana R (2000) Fluorescence studies of amphiphilic block copolymers in solution. In Alexandridis P, Lindman B (eds) Amphiphilic block copolymers self assembly and applications. Elsevier, Amsterdam... 

Hamley, I. 2004. Developments in Block Copolymer Science and Technology. Wiley, Hoboken, NJ. Hamley, I. 2006. Block Copolymers in Solution Fundamentals and Applications. Wiley, Hoboken, NJ. Harada, A., Hashidzume, A., and Takashima, Y. 2006. Supramolecular Polymers, Oligomers, Polymeric Betains. Springer, New York. 

Rodriguez-Hernandez J, ChecotF, Gnanou Y, Lecommandoux S. Toward smart nano-objects by self-assembly of block copolymers in solution. Prog Polym Sci 2005 30 691-724. 

Block copolymers are widely used industrially. In the solid and rubbery states they are used as thermoplastic elastomers, with applications such as impact modification, compatibilization and pressure-sensitive adhesion. In solution, their surfactant properties are exploited in foams, oil additives, solubilizers, thickeners and dispersion agents to name a few. Particularly useful reviews of applications of block copolymers in the solid state are contained in the two books edited by Goodman (1982,1985) and the review article by Riess etal. (1985). The applications of block copolymers in solution have been summarized by Schmolka (1991) and Nace (1996). This book is concerned with the physics underlying the practical applications of block copolymers. Both structural and dynamical properties are considered for melts, solids, dilute solutions and concentrated solutions. The book is organized such that each of these states is considered in a separate chapter. 

Because the essentials of micellization have been discussed in depth for poly(oxyethylene)-containing block copolymers, we do not describe experimental studies on styrenic block copolymers in solution in great detail. Instead, the features are summarized in tabular form (see Tables 3.1-3.4). Experiments on ionic block copolymers containing polystyrene are discussed in Section 3.6.2. 

Table 3.3 Studies of PS-PMMA block copolymers in solution... 

Among other approaches, a theory for intermolecular interactions in dilute block copolymer solutions was presented by Kimura and Kurata (1981). They considered the association of diblock and triblock copolymers in solvents of varying quality. The second and third virial coefficients were determined using a mean field potential based on the segmental distribution function for a polymer chain in solution. A model for micellization of block copolymers in solution, based on the thermodynamics of associating multicomponent mixtures, was presented by Gao and Eisenberg (1993). The polydispersity of the block copolymer and its influence on micellization was a particular focus of this work. For block copolymers below the cmc, a collapsed spherical conformation was assumed. Interactions of the collapsed spheres were then described by the Hamaker equation, with an interaction energy proportional to the radius of the spheres. 

Tuzar, Z. and Kratochvfl, P. (1976). Advances in Colloid and Interface Science, 6, 201. Tuzar, Z. and Kratochvfl, P. (1993). Micelles of block and graft copolymers in solutions. 

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