The scope of this Perspective is to highlight innovative contributions in the synthesis of well-defined complex macromolecular architectures and to emphasize the importance of these materials to polymer physical chemistry, physics, theory, and applications. In addition, this Perspective tries to enlighten the past and show possible pathways for the future. Among the plethora of polymerization methods, we briefly report the impact of the truly living and controlled/ living polymerization techniques focusing mainly on anionic polymerization, the mother of all living and controlled/living polymerizations. Through anionic polymerization well-defined model polymers with complex macromolecular architectures having the highest molecular weight, structural and compositional homogeneity can be achieved. The synthesized structures include star, comb/graft, cyclic, branched and hyberbranched, dendritic, and multiblock multicomponent polymers. In our opinion, in addition to the work needed on the synthesis, properties, and application of copolymers with more than three chemically different blocks and complex architecture, the polymer chemists in the future should follow closer the approaches Nature, the perfect chemist, uses to make functional complex macromolecular structures by noncovalent chemistry. Moreover, development of new analytical methods for the characterization/purification of polymers with complex macromolecular architectures is essential for the synthesis and properties study of this family of polymeric materials.

Two well-defined cyclic triblock terpolymers, missing pieces of the terpolymer morphology puzzle, consisting of poly(isoprene), polystyrene, and poly(2-vinylpyridine), were synthesized by combining the Glaser coupling reaction with anionic polymerization. An α,ω-dihydroxy linear triblock terpolymer (OH-PI 1,4 -b-PS-b-P2VP-OH) was first synthesized followed by transformation of the OH to alkyne groups by esterification with pentynoic acid and cyclization by Glaser coupling. The size exclusion chromatography (SEC) trace of the linear terpolymer precursor was shifted to lower elution time after cyclization, indicating the successful synthesis of the cyclic terpolymer. Additionally, the SEC trace of the cyclic terpolymer produced, after cleavage of the ester groups, shifted again practically to the position corresponding to the linear precursor. The first exploratory results on morphology showed the tremendous influence of the cyclic structure on the morphology of terpolymers.

CitationDesign of block copolymer membranes using segregation strength trend lines 2016 Mol. Syst. Des. Eng. Block copolymer self--assembly and non--solvent induced phase separation are now being combined to fabricate membranes with narrow pore size distribution, and high porosity. The method has the potential to be used with a broad range of tailor made block copolymers to control functionality and selectivity for specific separations. However, the extension of this process to any new copolymer is challenging and time consuming, due to the complex interplay of influencing parameters, such as solvent composition, polymer molecular weights, casting solution concentration, and evaporation time. We propose here an effective method for designing new block copolymer membranes. The method consists of predetermining a trend line for preparation of isoporous membranes, obtained by computing solvent properties, interactions and copolymer block sizes for a set of successful systems and using it as a guide to select the preparation conditions for new membranes. We applied the method to membranes based on poly(styrene--b--ethylene oxide) diblocks and extended it to newly synthesized poly(styrene--b--2--vinyl pyridine--b--ethylene oxide) (PS--b--P2VP--b--PEO) terpolymers. The trend line method can be generally applied to other new systems and is expected to dramatically shorten the path of isoporous membrane manufacture. The PS--b--P2VP--b--PEO membrane formation was investigated by in situ Grazing Incident Small Angle X--ray Scattering (GISAXS), which revealed a hexagonal micelle order with domains spacing clearly correlated to the membrane interpore distances. Eprint version

CitationSutisna B, Polymeropoulos G, Mygiakis E, Musteata V, Peinemann K-V, et al. (2016) Our results demonstrate that artificial channels can be designed for protein transport via block copolymer self--assembly using classical methods of membranes preparation. text goes here.

Tadpole polymers are excellent candidates to explore how architecture can influence self-assembly because they combine two topologies in the same molecule (ring polymer as the head and linear polymer as the tail). In this work, we synthesize well-defined tadpole homo-/co-/terpolymers derived from the appropriate chemical modification reactions of the corresponding 3-miktoarm star homo-/co-/ terpolymers via anionic polymerization, high vacuum techniques, and chlorosilane chemistry in combination with the Glaser coupling reaction. The 3-miktoarm star homo-/ co-/terpolymers bear two arms with t-butyl dimethylsiloxypropyl functional end-groups, whereas after deprotection, the ωhydroxyl chain-ends were modified to alkyne moieties. The dialkyne star polymers in the presence of Cu(I)Br and N,N,N′,N″,N″-pentamethyldiethylenetriamine were then transformed to well-defined tadpole homo-/co-/terpolymers. We employed strongly immiscible blocks to enable characterization using electron microscopy and X-ray scattering to explore how the molecular topology influences the self-assembled bulk-state microdomain morphologies.