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Peptide sciences developed dramatically as a result of routine use of solid-phase peptide synthesis and nowadays offer a rich set of well-established strategies to design and identify functional peptide sequences for advanced applications in materials sciences. Appropriate sequences for a wide range of interesting material targets, ranging from molecules to materials surfaces and internal interfaces, can be selected via combinatorial means, and sequence specificities within the resulting peptide-target interactions can be routinely investigated. Based on this understanding, macromolecular sciences can define new polymer structures that meet required functionalities or functional sequences with fully synthetic, nonpeptidic precision polymers to endeavor toward information-based design of next-generation, purpose-adapted macromolecules., (© 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

For the copolymerization of non-conjugated olefins and maleimides, it is known that under certain conditions periodic ABA monomer sequences are formed. In this work, such a copolymerization is used to create polymers which have defined (periodic) monomer sequences and can be functionalized after polymerization. The copolymerization of pentafluorophenol (PFP) active esters of 4-pentenoic acid and perillic acid with N -phenyl maleimide (PhMI) was studied in 1,2-dichloroethane (DCE) and 1,1,1,3,3,3-hexafluoro-2-phenyl-2-propanol (HFPP). In DCE and for the copolymerization of the PFP ester of 4-pentenoic acid and PhMI in HFPP, polymers were formed where the active esters were separated by at least one PhMI unit. The average number of separating PhMI units can be controlled by varying the feed ratio of the monomers. For the copolymerization of the PFP ester of perillic acid in HFPP, a preference for the formation of periodic copolymers was observed, where active esters were preferably separated from each other by a maximum of two PhMI moieties. Therefore, the copolymerization of said active ester containing monomers with PhMI provides a platform to create polymers in which reactive moieties are distributed along the polymer chain in different fashions. The active esters in the non-conjugated vinyl monomers could be used in a post-polymerization functionalization step to create functionalized polymers with defined monomer sequences in a modular way., Competing Interests: The authors declare no conflict of interest.

β-Hairpin formation is one of the fundamental folding actions in biomacromolecules. We present a linear triblock copolymer synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization, that is able to mimic on a very basic level hairpin formation by using π-π stacking interactions between phenyl and 2,3,4,5,6-pentafluorophenyl residues.

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.

Effects of pH, ionic strength, and type of salt (variation of anions) on the cloud-point temperature (T(CP)) of thermoresponsive poly(2-ethyl-2-oxazoline) star ionomers are investigated. T(CP) s can be varied in a wide range, from 10 to >95 °C, corresponding with the Hofmeister series and the ionization of the core. Addition of salt weakens the influence of pH. For star copolymer with an amine core similar trends are observed as for star copolymers with a carboxylic acid core, although the presence of a chaotropic salt affords an inversion of the effect of pH, that is, T(CP) s are lowest at pH 3, where the amine groups are fully protonated. This effect is likely due to the specific binding of chaotropic anions to the amine and ammonium groups, which is not observed for carboxylic acid groups., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Commercially available 1,2-PB was transformed into a well-defined reactive intermediate by quantitative bromination. The brominated polymer was used as a polyfunctional macroinitiator for the cationic ring-opening polymerization of 2-ethyl-2-oxazoline to yield a water-soluble brush polymer. Nucleophilic substitution of bromide by 1-methyl imidazole resulted in the formation of polyelectrolyte copolymers consisting of mixed units of imidazolium, bromo, and double bond. These copolymers, which were soluble in water without forming aggregates, were used as stabilizers in the heterophase polymerization of styrene and were also studied for their ionic conducting properties., (Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

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).