Conjugated polymers block copolymers

Recent advances in polymer chemistry have yielded better control over the architecture and polydispersivity of simple polymers, polymer-conjugates and block copolymers such that they can be efficiently produced and can spontaneously form sterically stabilized, nanoscale, self-assembling structures with macrophage evading properties. ... 

In these two decades remarkable progress has been made in the development of excellent catalysts for living and stereospecific acetylene polymerizations (10,26-28). The r-conjugated polymers prepared by the sequential polsrmerization are strictly limited to polyacetylenes, except for only a few examples. Thus, synthesis of tailor-made conjugated macromolecules such as end-functionalized polymers, block copolymers, star-shaped polymers is possible only in the case of substituted acetylenes. 

Recent advances in synthetic polymer preparation and formulation have enabled a rapid advancement of nanomedicine, with over 40 formulations being approved for routine human use in the last 20 years and many more currently in clinical development [6]. Examples include polymer-drug and protein conjugates [5], block copolymer polymeric micelles [7] and polyplexes developed for... 

One cannot rule out, however, the possible assumption that this effect is a consequence of an interaction of conjugated blocks in graft and block copolymers that may lead to the overlap of wave functions of various conjugated blocks, followed by an increase in conjugation efficiency in the polymers. 

Fig. 30 Types of nanocarriers for drug delivery, (a) Polymeric nanoparticles polymeric nanoparticles in which drugs are conjugated to or encapsulated in polymers, (b) Polymeric micelles amphiphilic block copolymers that form nanosized core-shell structures in aqueous solution. The hydrophobic core region serves as a reservoir for hydrophobic drugs, whereas hydrophilic shell region stabilizes the hydrophobic core and renders the polymer water-soluble.

Kim et al. have introduced silicon atoms in PPV block copolymers to confine the conjugation length and achieve blue EL materials. Copolymers 188-190 [215] and 191 [216] have been synthesized by Wittig-Horner and Knoevenagel condensation, respectively. The emission band in this series can be tuned between 410 and 520 nm, and ITO/polymer/Al PLEDs with turn-on voltages 7 V have been reported (Chart 2.41). 

The above approaches used the idea of conjugation length control in PTs by distorting the polymer backbone with bulky substituents as side groups. Hadziioannou and coworkers [509,510] demonstrated PL and EL tuning via exciton confinement with block copolymers... 

X. Kong and S.A. Jenekhe, Block copolymers containing conjugated polymer and polypeptide sequences synthesis and self-assembly of electroactive and photoactive nanostructures, Macromolecules, 37 8180-8183, 2004. 

Several groups have engaged in the study of linear polymer-dendrimer conjugates (i.e. architectural copolymers). These structures combine block copolymer and dendrimer branching features within one molecular architecture [69-71],... 

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