Synthetic hybrid materials

Roy D, Guthrie JT, Perrier S (2008) Synthesis of natural-synthetic hybrid materials from cellulose via the RAFT process. Soft Matira 4 145-155... 

Covalently connecting two incompatible polymers at their ends leads to a fascinating class of self-assembling materials [1]. Block copolymers constitute a well-studied and well-documented set of nanostructured hybrid materials [2], Many synthetic techniques are available for generating AB diblock, ABA triblock, ABC triblock and even more complicated block architectures [3,4], Furthermore, the thermodynamics governing the self-assembly... 

Miller and co-workers have recently prepared nanometer-scaled molecular dumbbells based on poly(benzyl ether) dendrons (G1-G4) and oligoimide spacers [64], Their synthetic approach involved the coupling of amine-terminated oligoimides to dendrons with a carboxylic acid focal point. The resulting hybrid materials were found to be quite soluble thus allowing their analysis by cyclic voltammetry in DMF. Consistent with Roncali s observation, the kinetics of reduction of the oligoimide core was not found to be limited by the presence of the dendritic wedges. 

Polymer-stabilized Au NPs have been the object of intense research in recent years because, apart from their intrinsic synthetic interest, these hybrid materials have interesting properties and potential applications. There are also several advantages in the use of polymers as stabilizers enhancement of long-term stability adjustment of solubility or amphiphilicity of nanoparticles, tuning of the properties of Au NPs, and the promotion of compatibility and processability. 

Vandermeulen, G.W.M., and Klok, H.-A. "Peptide/protein hybrid materials enhanced control of structure and improved performance through conjugation of biological and synthetic polymers". Macromol. Biosci. 4(4), 383-398 (2004). 

Fig. 6 Schematic representation of the synthetic route to obtain constitutional silica mesoporous membranes is (a) filled with mesostructured silica-CTAB, (b) then calcinated, (c) reacted with hydrophobic ODS and finally filled with the hydrophobic carriers. Generation of directional ion-conduction pathways which can be morphologically tuned by alkali salts templating within dynamic hybrid materials by the hydrophobic confinement of ureido-macrocyclic receptors within silica mesopores [130]...

Therefore, silanol species can be a driving force of the resulting organization in the hybrid material. More interestingly, silanols are now used as reactive supramolecular functions, that is to say as a synthetic tool allowing the association of molecular units and their further transformation, see below. On the other hand, these self-assembling properties do not appear to be clearly predictable, especially because in the Sol-Gel process other H-bonding species (mainly alcohol, water and sometimes solvent) are present and can disturb the silanol self-association. 

At the crossover between supramolecular and synthetic chemistry the hybrid materials represent a major field of science exploration and applications. In contrast with pure silica, the presence of the organic groups in R-[SiO, 5] (n>l) systems questions the possibility to have organization based on the presence of hydrophobic and hydrophilic parts. 

During the last decades, several studies reported the preparation of synthetic discrete supramolecular assemblies (4-8), polymers (1-9), and hybrid materials (10-12) that possess bases of nucleic acids as side groups or chain-end, which are used as precursors to conceive self-organized hybrid materials at nanometric scale. 

Among the various applications of SFM in polymer science, the imaging of heterogeneous synthetic polymeric materials (blends, copolymers, hybrid materials, etc.) is probably most widespread and can be considered the easiest task, in particular when the materials are (at least partly) glassy at the imaging... 

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