Amphiphilic Double-Brush Polymers Based on Itaconate Diesters

Abstract

Itaconic anhydride, a biosourced molecule, was readily transformed to polymerizable nonionic amphiphiles of the type R-Ita-R′; these amphiphiles carry an exo-chain double bond, which upon polymerization yielded amphiphilic doublebrush polymers, especially when R and R′ are immiscible, and consequently exhibit a tendency to self-segregate. DSC, WAXS, SAXS, and variable temperature FT-IR studies of these amphiphilic double-brush polymers confirm the occurrence of self-segregation followed by crystallization of the cetyl segments; in most cases a lamellar morphology is seen wherein the two immiscible segments form the alternating lamellae and the polymer backbone presumably lie along their interface. C16-Ita-HEG, which carries a hydrophobic cetyl chain and a hydrophilic heptaethylene glycol monomethyl ether unit, forms a hydrogel upon polymerization at concentrations above 2.5 wt %; an interesting feature of this hydrogel is that it exhibits a reversible thermal and shear-induced transformation to a sol, a property that could be of interest for biomedical applications.

Synthesis and Self‐Assembly of Mixed‐Graft Block Copolymers

“…Branched macromonomers can be viewed as linear diblock copolymers with a polymerizable functionality at the block junction. Typically, norbornene is used as the polymerizable functionality because it is highly active in ROMP, but a synthetic route based on an itaconate‐functionalized BMM has also been reported . As with the alternating copolymerization of macromonomers, the advantage of this synthetic strategy is that full grafting density can be ensured, and the side chain sequence is also controlled in a pseudo‐alternating fashion, resulting in an mGBCP with a defined structure.…”

A Calix[4]arene‐Based Cyclic Dinuclear Ruthenium Complex for Light‐Driven Catalytic Water Oxidation

“…The dinuclear calix [4]arene-based cyclic Ru complex dimer 1, bearinge ight tri(ethylene glycol)c hains as water-solubilizing groups,w as synthesized accordingt ot he route depicted in Scheme1.T he solubilizing groups were incorporated into the axial calix [4]arene-based ligand 9 in five steps by literature adaptedp rocedures, [49][50][51] startingf rom commercially available 4-tert-butylcalix [4]arene 1.T he target Ru complex dimer 1 was then synthesized through al igand exchange reaction of the precursor[ Ru(bda)(dmso) 2 ] 10 [52] with the phenylpyridine-functionalized calix [4]arene ligand 9 in ac hloroform/methanol mixture under an itrogen atmosphere.P urification of the crude product by column chromatography afforded the desired dinuclear complex dimer 1 in 50 %i solated yield. The structures of dimer 1 and all unknown precursors were elucidated by 1D and 2D NMR spectroscopy and high-resolution mass spectrometry.T he purity of the compounds were confirmed by elemental analysis.…”

“…The dinuclear calix[4]arene‐based cyclic Ru complex dimer 1 , bearing eight tri(ethylene glycol) chains as water‐solubilizing groups, was synthesized according to the route depicted in Scheme 1. The solubilizing groups were incorporated into the axial calix[4]arene‐based ligand 9 in five steps by literature adapted procedures, [49–51] starting from commercially available 4‐ tert ‐butylcalix[4]arene 1 . The target Ru complex dimer 1 was then synthesized through a ligand exchange reaction of the precursor [Ru(bda)(dmso) 2 ] 10 [52] with the phenylpyridine‐functionalized calix[4]arene ligand 9 in a chloroform/methanol mixture under a nitrogen atmosphere.…”

“…Boronic ester 8 was prepared in two steps starting from the respective pyridine boronic acid according to ref. [50].…”

Multilayered Lamellar Materials and Thin Films by Instant Self-Assembly of Amphiphilic Random Copolymers

“…Controlled self-assembly of (co)­polymers and related compounds is a key technology to construct ordered nanostructures and nanopatterns in functional materials, thin films, and devices for various applications (e.g., bioapplications, membranes, electronic devises, and lithography). − Among them, controlling sub-10 nm scale structures is often required to realize targeted properties and performance, while easy access to such small nanostructures is still challenging in self-assembly of polymers. For this purpose, two types of strategies have typically been examined: One is self-assembly of high-χ low- N block copolymers comprising short and incompatible chains (χ, Flory–Huggins interaction parameter; N , the total degree of polymerization) − and the other is that of (co)­polymers bearing short and incompatible side chains, including brush, graft, random, copolymers, and homopolymers. − The former method involves well-controlled block copolymers with narrow molecular weight distribution, because N and molecular weight distribution directly affect the domain spacing and the uniformness . However, the latter possibly affords the control of the domain size and structures by the side chain length and composition, and thus, N and molecular weight distribution may not affect the domain spacing.…”