Telechelic hydrogel

The synthetic systems described above have not been tested in vivo and their mechanical properties have not been determined. In our group, brfunctional telechelic hydrogelators were developed based on PEG cross-linked with UPy groups at both ends of the polymer (Fig. 6a) [123]. In dilute solutimi, stacking of UPy dimers results in the formation of nanolibrous structures, aided by additional urea hydrogen bonds in a hydrophobic pocket formed by long alkyl spacers. Above a critical concentration, bundling causes formatimi of a transient network (Fig. 6b). 

There are 22 chapters in the book and they cover the most important aspects of polymers as drugs, prodrugs, dmg delivery systems, and in situ prostheses. The major features promulgated are synthesis, derivatization, degradation, characterization, application, and evaluation techniques as well as new biodegradable materials, assemblies, hydrogels, telechelic polymers, derivatized polysaccharides, micro- and nanoparticles, mimetic... 

Fig. 6 Ureido-pyriinidinone (UPy)-based hydrogelators. (a) Chemical structure of telechelic UPy-functionalized PEG. (b) Chemical stracture of monofunctional UPy-functional PEG monomethylether. (c) (1-4) Formation of fibers and subsequent bundling, leading to a 3D hydrogel [131]. Copyright (c) Wiley-VCH Verlag GmbH Co. KGaA, Weinheim. (d) Chemical structures of chain-extended UPy- modified PEGs [127]. (e) Chemical structure of RGD-peptide functionalized with the UPy moiety [128]...

Amphiphilic ABA triblock copolymers, capable of forming pH-sensitive reversible hydrogels useful in waterborne formulations, have been prepared by anionic polymerization and explored in aqueous media. Telechelic polyelectrolytes, for example, poly(acrylic acid) (PAA) end-capped by PSt short blocks, were prepared by the coupling agent method using tert-butyl acrylate (tBA) and postpolymerization hydrolysis to obtain the desired PAA central block (Scheme 3). ... 

The goal of this study is to explore the synthesis of amphiphilic hydrogels using telechelic PEG and surface-ftinctionalized poly(benzyl ether) dendrimers. The networks formed should have randomly distributed linear (hydrophilic) and globular (hydrophobic) segments, but with precisely engineered size and chemical composition of both components. 

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