Synthesis and Thermoreversible Gelation Properties of Main-Chain Poly(pyridine-2,6-dicarboxamide-triazole)s

Designing luminescent diimine-Cu (I)-phosphine complexes by tuning N-ligand and counteranions: correlation of weak interactions, luminescence and THz absorption spectra

Herein, six new [Cu(N^N)(P^P)]+/0 complexes with different N-ligand and counteranions [Cu2(dmp)2(bdppmapy)I2] (1), [Cu2(dmp)2(bdppmapy)(CN)2]·3CH3OH (2), [Cu(dmp)(bdppmapy)](BF4) (3), [Cu(dmp)(bdppmapy)](ClO4) (4), [Cu(phen)(bdppmapy)](BF4) (5), [Cu(phen)(bdppmapy)](ClO4) (6) have been synthesized and characterized (bdppmapy = N,N-bis[(diphenylphosphino)methyl]-2-pyridinamine,...

Infinite coordination polymer networks: metallogelation of aminopyridine conjugates and in situ silver nanoparticle formation

Herein we report silver(i) directed infinite coordination polymer network (ICPN) induced self-assembly of low molecular weight organic ligands leading to metallogelation. Structurally simple ligands are derived from 3-aminopyridine and 4-aminopyridine conjugates which are composed of either pyridine or 2,2'-bipyridine cores. The cation specific gelation was found to be independent of the counter anion, leading to highly entangled fibrillar networks facilitating the immobilization of solvent molecules. Rheological studies revealed that the elastic storage modulus (G') of a given gelator molecule is counter anion dependent. The metallogels derived from ligands containing a bipyridine core displayed higher G' values than those with a pyridine core. Furthermore, using single crystal X-ray diffraction studies and ¹H-¹⁵N two-dimensional (2D) correlation NMR spectroscopy, we show that the tetracoordination of silver ions enables simultaneous coordination polymerization and metallosupramolecular cross-linking. The resulting metallogels show spontaneous, in situ nanoparticle (d < 2-3 nm) formation without any additional reducing agents. The silver nanoparticle formation was followed using spectroscopic studies, and the self-assembled fibrillar networks were imaged using transmission electron microscopy (TEM) imaging.

Photochromic, organogelating and self-sorting behaviour of di-(dithienylethene) derivatives

They wouldn't mix! – Narcissistic self-sorting was found to exist in a 1 : 1 mixture of the two photoisomers of a di-(dithienylethene)-containing organgelator.

A photo-responsive poly(amide–triazole) physical organogel bearing azobenzene residues in the main chain

The synthesis of a click poly(amide–triazole) bearing multiple azobenzene units along the main chain was reported.

Different Gelation and Self-Sorting Properties of Two Isomeric Polyamides Owing to the Parallel versus Anti-Parallel Alignment of Backbone Dipoles

Two isomeric bottlebrush polyamides P-1 and A-1, with the same repeating monomer dipole units aligned along the polymer backbone in pseudo-parallel and pseudo-antiparallel fashion, respectively, were synthesized and characterized. Both polymers can form thermoreversible gels with aromatic solvents but P-1 was found to show inferior gelation strength compared with that of A-1. Furthermore, despite their close structural resemblance, a 1:1 mixture of the P-1 and A-1 polymers was shown to exhibit self-sorting in the gel state. Gel formation was found to be a kinetically trapped process through hydrogen bonding, π-π stacking interactions, and side chain interdigitation. The different gelation and self-sorting properties can be explained by the local dipole-dipole interactions originating from the different modes of backbone dipole alignment. In single gel systems, the antiparallel-aligned dipoles in A-1 facilitated a more compact molecular packing owing to the enthalpically more favorable polymer chain association. On the other hand, the parallel-aligned dipoles in P-1 gave rise to a less stable head-to-head packing, which had difficulties to convert to the more stable head-to-tail packing in a kinetically trapped environment. In the mixed gel system, it is the unfavorable hetero-polymer mismatch dipole-dipole interaction that inhibited the mixing of the A-1 and P-1 polymers and led to self-sorting.

A class of polytriazole metallogels via CuAAC polymerization: preparation and properties

Coordination-driven polytriazole metallogels possess good self-healing abilities.

Synthesis and properties of polyurethane urea with pyridine-2,6-dicarboxamide moieties in their structure

The inclusion of 2,6-pyridinedicarboxamide into polyurethanes structure strongly influenced their morphology, surface and thermo-mechanical properties. The 2,6-pyridinedicarboxamide units adopt syn-syn conformations into polyurethane matrix.

Formation of long sub-chain hyperbranched poly(methyl methacrylate) based on inhibited self-cyclization of seesaw macromonomers

Well-defined hyperbranched PMMA almost without self-cyclization was obtained through a click reaction, facilitated by a high concentration, good solvent and disubstituted chain ends.

Transition from low molecular weight non-gelating oligo(amide-triazole)s to a restorable, halide-responsive poly(amide-triazole) supramolecular gel

Switching between non-gelating and gelating polymer: the cation vs anion game.