Brush type architectures

Star-type and Bottle-Brush-type Architectures... 

A number of different types of copolymers are possible with ATRP—statistical (random), gradient, block, and graft copolymers [Matyjaszewski, 2001]. Other polymer architectures are also possible—hyperbranched, star, and brush polymers, and functionalized polymers. Statistical and gradient copolymers are discussed in Chap. 6. Functionalized polymers are discussed in Sec. 3-16b. 

There are many polymer architectures beyond chains such as stars, combs, and brushes. An example of a star-type oligophenylene is structure 100.276 It can be described as possessing three oli-... 

The synthesis of polyelectrolytes with well-defined architectures, however, has imposed many challenges to the polymer chemists. Many polymerization techniques are not tolerable to the ionic functional groups. In most cases, preparation of polyelectrolytes involves the protection and deprotection of the ionic groups in the monomer. For polyelectrolytes with different architectures, various synthetic strategies are required. Recently, we have synthesized various complex architectures containing polyelectrolytes with different nonlinear topologies, such as combshaped [22], hyperbranched [23-25], Janus-type [26], stars [27, 28] and brushes [29-31],... 

A different approach was used by Milner [326] in order to predict the phase diagram for asymmetric copolymer architectures (for example A2B, A3B etc. types of miktoarm stars). The free energy of the system can be calculated by summing the free energies of the polymer brushes existing on the two sides of the interphase. Milner described the effects of both chain architecture (i.e., number of arms) and elastic (conformational) asymmetry of the dissimilar chains, in the strong segregation limit, by the parameter... 

Most of the publications on polycations for DNA condensation possessing a steric stabilizer deal with the influence of the polymer architecture on the properties of the polyplexes (physico-chemical characteristics and transfection efficiency). Two types of architectures are mainly studied linear copolymers with block and/or graft (eventually brush) architectures (Scheme 17). The steric stabilizers most commonly used are based on ethylene glycol or contain hydroxyl groups such as hydroxyethyl methacrylate or sugars (only a few examples are presented here because sugar-based polycations are out of the scope of this review). 

Ishizu, K., Satoh, J. and Sogabe, A. (2004) Architecture and solution properties of AB-type brush-block-brush amphiphilic copolymers via ATRP techniques. /. Colloid. Inter/. Sci., 274, 472-479. 

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