We herein report the synthesis and characterization of dual stimuli-responsive poly­(2-iso-propyl-2-oxazoline)-block-poly­(2-acrylamido glycolic acid) (PiPrOx-b-PAGA) double hydrophilic block copolymers (BCPs) by an effective combination of ring-opening and reversible addition–fragmentation chain transfer (RAFT) polymerization. The resulting materials are responsive toward several external triggers: (1) the PiPrOx segment undergoes a coil-to-globule transition upon heating above the cloud point temperature (T CP), (2) the PAGA block chelates M2+ metal ions and provides straightforward access to nanostructured hybrid materials, and (3) prolonged heating above the T CP for PiPrOx enables crystallization-driven solution self-assembly (CDSA) toward anisotropic micelles and superstructures. We are further able to show that the cloud point temperature (T CP) of PiPrOx-b-PAGA micelles can be tuned from ∼30 to 68 °C by varying either the BCP composition (PiPrOx to PAGA ratio) or by the amount of metal ions being present. The different aggregates were characterized by transmission electron microscopy (TEM), wide-angle X-ray scattering (WAXS), and dynamic light scattering (DLS). Our results indicate that micellar size, shape, and T CP are closely connected to BCP composition and the nature of chelated metal ions. In our opinion, such inorganic–organic hybrid materials are of interest with regard to (photo)­catalysis, as sensors, or as potential drug delivery systems.

In this work, we present an ew synthetics trategy for fourfold-substituted perylene monoimides via tetrabrominated perylene monoanhydrides. X-ray diffraction analysis unveiled the intramolecular stacking orientation between the substituents and semicircular packing behavior.W eo bserved the remarkable influence of the substituent on the longevity and nature of the excited state upon visible light excitation.I nt he presenceo fp oly(dehydroalanine)-graftpoly(ethylene glycol)g raft copolymers as solubilizing template, the chromophores are capable of sensitizing [Mo 3 S 13 ] 2À clustersi na queous solution for stable visible light driven hydrogen evolution over three days.

Three triggers result in two measurable outputs from polymeric sensors: multiresponsive polyampholytic graft copolymers respond to pH‐value and temperature, as well as the type and concentration of metal cations and therefore, allow the transformation of external triggers into simply measurable outputs (cloud point temperature (TCP) and surface plasmon resonance (SPR) of encapsulated silver nanoparticles). The synthesis relies on poly(dehydroalanine) (PDha) as the reactive backbone and gives straightforward access to materials with tunable composition and output. In particular, a rather high sensitivity toward the presence of Cu2+, Co2+, and Pb2+ metal cations is found.

An effective strategy to enhance the performance of inorganic semiconductors is moving towards organic‐inorganic hybrid materials. Here, we report the design of core–shell hybrid materials based on a TiO2 core functionalized with a polyampholytic (poly(dehydroalanine)‐graft‐(n‐propyl phosphonic acid acrylamide) shell (PDha‐g‐PAA@TiO2). The PDha‐g‐PAA shell facilitates the efficient immobilization of the photosensitizer Eosin Y (EY) and enables electronic interactions between EY and the TiO2 core. This resulted in high visible‐light‐driven H2 generation. The enhanced light‐driven catalytic activity is attributed to the unique core–shell design with the graft copolymer acting as bridge and facilitating electron and proton transfer, thereby also preventing the degradation of EY. Further catalytic enhancement of PDha‐g‐PAA@TiO2 was possible by introducing [Mo3S13]2− cluster anions as hydrogen‐evolution cocatalyst. This novel design approach is an example for a multi‐component system in which reactivity can in future be independently tuned by selection of the desired molecular or polymeric species.

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Ordered mesoporous silica has been drawn great interest in many areas of modern science and technology. In this study, mesoporous silica KIT-6 was modified with 3-mercaptopropyl-trimethoxysilane by sono-chemical method and reflux. Low-angle powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) images confirmed the presence well-ordered arrangement of large pores and a relatively ordered mesostructure for the functionalized materials. The nanocomposites of polyamide-6 and modified-KIT (3 and 6 wt %) were prepared under reflux and followed by sonication for 2h. The prepared hybrid nanocomposites were characterized by Fourier transform-infrared spectroscopy, XRD, field emission-scanning electron microscopy and TEM techniques. Thermogravimetric analysis data showed that the onset of decomposition temperature of the nanocomposites was higher than that of pristine polyamide-6, shifting toward higher temperatures as the amount of modified-KIT was increased. V C 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43098.

Citric acid (CA) with one hydroxyl and three carboxyl groups exists widely in citrus fruits and pineapples, where it is the main organic acid. In this article, nanosized CA‐modified ZnAl‐layered double hydroxide (CA‐LDH) was synthesized by coprecipitation method in aqueous media. Several nanocomposite (NC) films of poly(vinyl alcohol) (PVA) were prepared by casting through the dispersion of the CA‐LDH into the PVA aqueous solution under ultrasonic irradiation. The structures of individual layers of CA‐LDH and PVA/CA‐LDH NC films were characterized by X‐ray diffraction (XRD), Fourier transform infrared, field emission scanning electron microscopy, and transmission electron microscopy techniques. Uniform dispersion of LDH nanoplatelets in PVA matrix was observed. The thermal stability of the NC was study by thermogravimetric analysis technique, and the results show that the thermal properties were improved as compared with the original PVA. The mechanical properties of the PVA/CA‐LDH NCs are obviously enhanced compared to that of neat PVA. Uniform distribution of clay due to intimate interaction between clay and polymer appears to be the cause for improved properties. The UV–Visible transmission spectra of the composite films exhibited that, the samples retained high optical clarity and they could be potentially used in the packaging industry. POLYM. COMPOS., 38:E128–E136, 2017. © 2016 Society of Plastics Engineers

Double hydrophilic copolymers consist of two chemically different but water-soluble segments. We present synthetic approaches and both established as well as emerging applications such as photocatalysis or sensing.