Search

The formation of ternary inclusion complexes of γ-cyclodextrin (γ-CD) with two different pairs of interacting monomers (4-vinylpyridine (4VP) with styrenesulfonate (SS), which can interact through attractive Coulombic interactions, and styrene (S) with 2,3,4,5,6-pentafluorostyrene (PFS), which interact through quadrupole interactions) is studied. Ternary inclusion complexes are formed for both monomer pairs, but 4VP and SS are included in the complexes in approximately the same ratio as is present in solution, whereas S and PFS are preferentially included as a pair. The influence of the ternary inclusion complexation on the copolymerization was studied. For the copolymerization of 4VP with SS no significant influence was found, whereas an enhanced tendency toward alternating copolymerization was found for the copolymerization of S and PFS in the presence of γ-CD, which is ascribed to the preferential heteroinclusion of the monomers in the γ-CD cavity. [ABSTRACT FROM AUTHOR]

A tri(ethyleneglycol)-containing lactide analogue was synthesized via thiol–enechemistry between a bifunctional triethylene glycol and allyl lactide.Subsequent tin octoate catalyzed ring-opening polymerization yieldedwell-defined poly(lactide)-graft-poly(ethylene glycol)copolymers with molecular weights of 6 × 103 g/mol and polydispersity indices of 1.6. The tri(ethylene glycol)chains along the copolymers contain azide termini that are capableof efficient postpolymerization functionalization. The utility ofthis strategy was demonstrated via successful Staudinger ligationto install the Gly-Arg-Gly-Asp-Ser (GRGDS) peptide. [ABSTRACT FROM AUTHOR]

A series of copolymers with varying degrees of alternation are synthesized by free-radical polymerization from 2,3,4,5,6-pentafluorostyrene (PFS) and propargyl-containing styrene derivatives. The degree of alternation varied with the electronic nature of the styrene derivative: random copolymers were obtained using monomers with electron withdrawing moieties, whereas increasingly alternating copolymers were obtained by increasing the electron donating nature of the substituent. The copolymers could be functionalized in an orthogonal fashion using a nucleophilic substitution (with thiols) to functionalize PFS and the copper-catalyzed 3 + 2 cycloaddition between azides and the alkyne of the propargyl groups. This methodology allows for the facile synthesis of functional alternating copolymers.

We report the first attachment of polymers with pendant vinyl groups to hydrogen-terminated silicon(111) (Si(111)-H); 1,2-polybutadiene (M(w) = 3200-3500 g/mol) was attached to Si(111)-H under mild conditions at room temperature with visible light. We also report the partial functionalization, in solution, of 1,2-polybutadiene with various thiols using thiol-ene chemistry and the subsequent attachments of these compounds to Si(111)-H. The partially functionalized or unfunctionalized polybutadienes allow further functionalization at the surface through their unreacted carbon-carbon double bonds. We present this as a useful strategy for silicon surface modification. Surfaces were characterized with contact angle goniometry, spectroscopic ellipsometry, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and atomic force microscopy (AFM).