Micellization of cationic amphiphilic copolymers

The earlier studies in this area, mostly those of Selb and Gallot [190], were devoted to vinylpyridine (2VP and 4VP) containing block copolymers, readily accessible by anionic sequential polymerization and which could be transformed into water-soluble cationic species by quaternization or by simple protonation at low pH. The more recent development, pioneered by Armes and co-workers [57, 93, 191], concerns the micellization of amino-methacrylate-based block copolymers. 

In fact, the first systematic micellization studies of copolymers containing cationic hydrophilic blocks were those of Selb and Gallot, who have also given a review of this topic [190]. The typical polyelectrolyte copolymers investigated by these authors were polystyrene-b-poly(quaternized 4-vinylpyridine) PS-PQV4P with the following structure  

Similar to their work on anionic block copolymers, Eisenberg and co-workers [178, 192] have shown that crew-cut micelles can be obtained with PS-PQ4VP of high PS content. 

A typical example of the polyelectrolyte effect of quaternized PS-P4VP copolymers was reported by Calderara [126] and Riess and Hurtrez [129], The P4VP block is soluble in methanol, whereas the corresponding quaternized block PQ4VP, obtained with methyl iodide, is soluble in water. The micellar characteristics of a diblock copolymer with Nps= 154 

So-called schizophrenic block copolymers containing tertiary amine methacrylic sequences were developed in the recent years by Armes and co-workers [57, 93, 193,194] and Liu and Armes [191]. They offer interesting combinations of solubility properties versus pH, temperature and electrolytes that make them very attractive for micellization studies. These authors investigated essentially the combination of four types of tertiary amine ethylmethacrylates blocks with the following structures  

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