Many inspiring achievements have been made in inducing chiral amplification in helical polymers; however, the induction of helical chirality in random coil polymers by the intermolecular noncovalent force in solutions so far is still an intractable task, which is almost only accomplishable in biopolymer systems. In this contribution, we found that a random coil poly(Npropargylamide) with an L-or D-alanine residue as the pendant (P-L(or -D)-ala-NH 2 ) can be induced to form a predominantly onehanded helical structure in an aqueous solution by complexing with metal ions, including Cu 2+ and Ag + . The random coil to predominantly one-handed helix transformation and the chiral amplification therein were clearly evidenced by the remarkable red-shift of the UV−vis absorption peak, the occurrence of strong circular dichroism (CD), and the sharp increase in the absolute value of specific rotation. When Cu 2+ was used as an inducer, the CD and UV−vis absorptions of P-L-ala-NH 2 were barely affected by heating and changing anions, demonstrating the high stability of the induced helical structure. The results obtained from CD, UV−vis, resonance Raman, Fourier transform infrared (FT-IR), and X-ray photoelectron spectroscopies and differential scanning calorimetry indicate that a contracted cis-cisoidal helical structure was formed in the polymer main chain through the generation of cis nearly square-planar complexes between each Cu 2+ ion and the four nitrogens of two pendants. The metal ion coordination concurrently provided appropriate linkage among the pendants and reduced the pendant flexibility, thus endowing the main chain with helicity and triggering chiral amplification. Inspired by this mechanism, a universal and convenient methodology for preparing helical polymer/metal ion complexes and the corresponding chiral materials from random coil polymers may be established.

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The chiral composite materials were synthesized by the helical polymers directly compounded with the substrate at present, due to changes in chemical bonds and steric hindrance during the compounding process...

The stimuli-responsive circularly polarized luminescence (CPL) property is highly desirable in the development of advanced multifunctional optical materials. However, the fabrication of CPL solid materials showing stimuli-responsive behavior in terms...

Reversible addition−fragmentation chain-transfer (RAFT)-mediated hybrid emulsion polymerization is an in situ growth method of increasing interest for preparation of colloidal polymers/inorganic hybrid latex with precise structures and properties. However, the challenges of the conventional organic sulfur-based RAFT agents causing color and undesired odor problems still attract attention. In response to this problem, herein, a cationic amphipathic statistic sulfur-free (SF) macro-RAFT agent with a vinyl end group is proposed to disperse organic pigment particles (C.I. Pigment Red 170), where the vinyl group is the living point to regulate the sulfur-free and surfactant-free RAFT hybrid emulsion polymerization of methyl methacrylate (MMA) or MMA with butyl acrylate (BA). Benefitting from this SF macro-RAFT agent acting as both coupling agent and stabilizer, the "living" chain growth of the polymers onto the C.I. Pigment Red 170 surface causes the formation of encapsulating pigment hybrid particles as proven by size-exclusion chromatography and transmission electron microscopy analyses. As a proof-of-concept experiment, the film-forming P(MMA-co-BA)/pigment hybrid latex particles are applied to textile colorants to pad dyeing cotton fabric. Owing to the unique structure of hybrid particles with high pigment content (81.3%), the dyed cotton fibers exhibit high color strength, dryand wet-rubbing fastness, good air permeability, and softness in comparison with the traditional mixture system. This study will not only broaden the area of RAFT-mediated hybrid emulsion polymerization for preparing hybrid particles but also provide a facile application for clear production.

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Although the supramolecular helical structures of biomacromolecules have been studied, the examples of supramolecular systems that are assembled using coils to form helical polymer chains are still limited. Inspired by enhanced helical chirality at the supramolecular level in metal coordination-induced protein folding, a series of alanine-based coil copolymers (poly-(L-co-D)-ala-NH 2 ) carrying (L)-and (D)-alanine pendants were synthesized as a fresh research model to study the cooperative processes between homochirality property and metal coordination. The complexes of poly-(L-co-D)-ala-NH 2 and metal ions underwent a coil-to-helix transition and exhibited remarkable nonlinear effects based on the enantiomeric excess of the monomer unit in the copolymers, affording enhanced helical chirality compared to poly-(L-co-D)-ala-NH 2 . More importantly, the synergistic effect of amplification of asymmetry and metal coordination triggered the formation of a helical molecular orbital on the polymer backbone via the coordination with the d orbital of copper ions. Thus, the helical chirality enhancement degree of poly-(L-co-D)-ala-NH 2 /Cu 2+ complexes (31.4) is approximately 3 times higher than that of poly-(L-co-D)-ala-NH 2 /Ag + complexes (9.8). This study not only provides important mechanistic insights into the enhancement of helical chirality for self-assembly but also establishes a new strategy for studying the homochiral amplification of asymmetry in biological supramolecular systems.