Host-guest polymerization

Arshady R, Mosbach K. S3mthesis of substrate-selective polymers by host-guest polymerization. Maktomol Chem 1981 182 687-692. 

C SPs. The assembly belongs to the class of clathrates (inclusion compounds) that have interest for separation processes. Single chains are confined in small channels (diameter — 6 A) for a wide variety of crystalline adducts. These systems suggests that smoothed-out effects assist rhe formation of host-guest polymeric assemblies in addition to localized interactions. The nonlocalized effects may arise from the suppression of... 

It has been shown that N-vinylearbazole and vinyl ethers can be used for the cationic host-guest polymerization in MCM-41 and MCM-48 mesoporous molecular sieves, leading to new polymer/MCM-41 and polymer/MCM-48 host-guest hybrid materials. " It seems that the molecular weight and the degree of the loading of the enclosed polymers ean be adjusted to a certain degree by modification of the polymerization conditions. 

Spange, S. Graser, A. Huwe, A. Kremer. F. Tintemann, C. Behrens, P. Cationic host-guest polymerization of N-vinylcarbazole and vinyl ethers in MCM-41, MCM-48. and nanoporous glasses. Chem. Eur. J. 2001, 7. 3722-3728. 

The self-assembly of natural and synthetic multifunctional unimers occurs, in fact, by a combination of classical molecular recognition and growth mechanisms. Self-assembled, reversible structures include linear, helical, columnar, and tubular polymers micelles monolayers and three-dimensional phases and networks. Self-assembled systems based on an interplay between covalent chains and supramolecular interactions are also important. Typical examples are side-chain SPs (Chapter 5), host-guest polymeric composites and dendrimers (Chapters 2 and 7), polymers with mechanical bonds (Chapter 8), and block copolymers (Chapters 9-11). 

The last system included in Table 2, the tobacco mosaic virus (TMV), illustrates the induction of helicity in host-guest polymeric assemblies [3,126], Columnar, helical, and helical-columnar assemblies often have a cavity in which guest molecules can be hosted. A cavity of only 6 A diameter can host a polymer chain for instance, stacks of a-cyclodextrin rings can host a poly(ethylene oxide) chain [141] without induction of helicity. Columnar stacks have also been observed with... 

Another example of a side-chain supra-raolecular polymer is prepared from poly(4-vinylpyridine) and H-bonding side chains [32-35]. In this case, mesogenic side-chain groups are directly attached to the polymer backbone and liquid-crystalline polymers such as 19 are formed by the noncovalent interaction [33]. This molecular design has been used to incorporate functional molecules into liquid-crystalline, host-guest polymeric systems [32]. 

Ffg. 7 Structure of electric field effect type capacitor using the host-guest polymerized membrane. 

Kitagawa and coworkers have recently described an interesting but different host-guest-polymerization concept to synthesize cross-linked polymers such as polystyrene, methylmethacrylate, and vinylacetate with pseudo-crystallinity in non-photochemical route [57]. In order to achieve this, they have first incorporated the cross-linker 2,5-divinyl-benzene-1,4-dicarboxylate (DVTP) into the porous CP [Cu(DVTP)(triethylenediamine)o.5] (51). The host framework containing porous channels with dangling vinyl groups provides a suitable environment for radical polymerization of these monomers as shown in Fig. 31. This is obviously different from photopolymerization by [2+2] cycloaddition reaction. 

Loh, X.J. Supramolecular host-guest polymeric materials for biomedical applications. Mater. Horiz. 2014(1), 185-195 (2013). doi 10.1039/C3MH00057E... 

The calculation of the binding energies in different host-guest polymeric systems has allowed us to hypothesize a competitive mechanism for the interpretation of their properties. In particular, the competition between the host-host and guest-host hydrogen-bonding and electrostatic interactions is at the root of some properties of the considered materials. 

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