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Macromolecular Rapid Communications

Raquel de la Campa, Diego García, Sandra Rodríguez, Gabino A Carriedo, Alejandro Presa Soto
The direct chemical functionalization of poly(spirophosphazene) [NP(O2 C12 H8 )]n (1) can be performed by the lithiation of the aromatic rings at low temperature using Schlosser's base (Li(t) Bu/KO(t) Bu or "superbase"), and the subsequent reaction with various electrophiles such as ClSiMe3 , ClPPh2 , or MeOB(O2 C6 H12 ) (MeOBpin). The functionalized polymers, isolated in very high yields (>90%) and without degradation of the polymeric chains, have an average degree of substitution per repeat unit ranging from 0...
March 27, 2017: Macromolecular Rapid Communications
Yixuan Song, Kevin P Meyers, Joseph Gerringer, Ramesh K Ramakrishnan, Mohammad Humood, Shuang Qin, Andreas A Polycarpou, Sergei Nazarenko, Jaime C Grunlan
A self-healable gas barrier nanocoating, which is fabricated by alternate deposition of polyethyleneimine (PEI) and polyacrylic acid (PAA) polyelectrolytes, is demonstrated in this study. This multilayer film, with high elastic modulus, high glass transition temperature, and small free volume, has been shown to be a super oxygen gas barrier. An 8-bilayer PEI/PAA multilayer assembly (≈700 nm thick) exhibits an oxygen transmission rate (OTR) undetectable to commercial instrumentation (<0.005 cc (m(-2) d(-1) atm(-1) ))...
March 27, 2017: Macromolecular Rapid Communications
Koichiro Beppu, Yuki Nagashima, Mituo Hara, Shusaku Nagano, Takahiro Seki
The microphase separation and photoalignment behavior of a diblock copolymer consisting of two kinds of side chain liquid crystalline (LC) polymers are investigated. Here, the mesogens of photoresponsive azobenzene and non-photoresponsive cyanobiphenyl are introduced in the side chains. The azobenzene and cyanobiphenyl mesogens orient homeotropically and planarly, respectively, in a thin film state. The combination of these contrasting orienting properties leads to a formation of vertically oriented lamella in the microphase separation structure...
March 24, 2017: Macromolecular Rapid Communications
Serter Luleburgaz, Meir Abuaf, Umit Tunca, Gurkan Hizal, Hakan Durmaz
l-Ascorbic acid, commonly known as vitamin C and one of the most important biological compounds, is converted to a α,ω-diene monomer and subsequently polymerized for the first time by acyclic diene metathesis. Various experimental conditions such as polymerization medium, catalyst type, temperature, and monomer/catalyst ratio are studied. The moderate molecular weight polymers are achieved when the polymerizations are conducted under bulk conditions employing the Grubbs first generation (G1) or Hoveyda-Grubbs second generation catalyst (HG-2)...
March 21, 2017: Macromolecular Rapid Communications
Yurim Shin, Chang Eun Song, Woo-Hyung Lee, Sang Kyu Lee, Won Suk Shin, In-Nam Kang
A new acceptor-donor-acceptor (A-D-A) small molecule based on benzodithiophene (BDT) and diketopyrrolopyrrole (DPP) is synthesized via a Stille cross-coupling reaction. A highly conjugated selenophene-based side group is incorporated into each BDT unit to generate a 2D soluble small molecule (SeBDT-DPP). SeBDT-DPP thin films produce two distinct absorption peaks. The shorter wavelength absorption (400 nm) is attributed to the BDT units containing conjugated selenophene-based side groups, and the longer wavelength band is due to the intramolecular charge transfer between the BDT donor and the DPP acceptor...
March 21, 2017: Macromolecular Rapid Communications
Wen Zhu, Liangcai Zhang, Yongming Chen, Ke Zhang
An ultraviolet (UV)-cleavable bottlebrush polymer is synthesized using the "grafting-onto" strategy by combining living radical polymerization and copper-catalyzed azide-alkyne cycloaddition (CuAAC). In this approach, reversible addition-fragmentation chain transfer polymerization is used to prepare a poly(methylacrylate) backbone with azide side groups, while atom transfer radical polymerization is employed to prepare polystyrene (PS) side chains end-functionalized with o-nitrobenzyl (UV-cleavable) propargyl groups...
March 21, 2017: Macromolecular Rapid Communications
Zhongkai Wang, Liang Yuan, Mitra S Ganewatta, Meghan E Lamm, Md Anisur Rahman, Jifu Wang, Shengquan Liu, Chuanbing Tang
Epoxy polymers (EPs) derived from soybean oil with varied chemical structures are synthesized. These polymers are then cured with anhydrides to yield soybean-oil-derived epoxy thermosets. The curing kinetic, thermal, and mechanical properties are well characterized. Due to the high epoxide functionality per epoxy polymer chain, these thermosets exhibit tensile strength over an order of magnitude higher than a control formulation with epoxidized soybean oil. More importantly, thermosetting materials ranging from soft elastomers to tough thermosets can be obtained simply by using different EPs and/or by controlling feed ratios of EPs to anhydrides...
March 21, 2017: Macromolecular Rapid Communications
Jongchan Lee, Jin Chul Kim, Hoyeol Lee, Sungjin Song, Heesoo Kim, Moonhor Ree
Three different series of brush polymers bearing glucosyl, maltosyl, or maltotriosyl moiety at the bristle end are successfully prepared by using cationic ring-opening polymerization and two sequential postmodification reactions. All brush polymers, except for the polymer containing 100 mol% maltotriosyl moiety, demonstrate the formation of multibilayer structure in films, always providing saccharide-enriched surface. These self-assembling features are remarkable, regarding the bulkiness of saccharide moieties and the kink in the bristle due to the triazole linker...
March 21, 2017: Macromolecular Rapid Communications
Yunxia Qian, Hongmei Liu, Haijian Tan, Qingmin Yang, Shuchen Zhang, Lingui Han, Xuegang Yi, Li Huo, Hongchi Zhao, Yonggang Wu, Libin Bai, Xinwu Ba
A potential real-time imaging water-soluble fluorescent polymer (P3) is facilely prepared via one-pot method. For P3, tetraphenylethene unit serves as the fluorescent unit, poly(acryloyl ethylene diamine) (a kind of polyelectrolyte) with specific degree of polymerization acts as water-soluble part. (1) H-NMR, gel permeation chromatography (GPC), UV-vis spectroscopy, photoluminescence (PL), and confocal laser scanning microscopy are undertaken to characterize the structure and property of P3. The results of wash-free cellular imaging show that the signal-to-noise ratio is high as the concentration of P3 is 50 μg mL(-1) ...
March 21, 2017: Macromolecular Rapid Communications
Shunjie Liu, Xun Zhao, Hongchen Guo, Yusheng Qin, Xianhong Wang, Fosong Wang
Due to the axial group initiation in traditional (salen)CoX/quaternary ammonium catalyst system, it is difficult to construct single active center propagating polycarbonates for copolymerization of CO2 /epoxides. Here a redox-responsive poly(vinyl cyclohexene carbonate) (PVCHC) with detachable disulfide-bond backbone is synthesized in a controllable manner using (salen)CoTFA/[bis(triphenylphosphine)iminium, [PPN]TFA binary catalyst, where the axial group initiation is depressed by judiciously choosing 3,3'-dithiodipropionic acid as starter...
March 21, 2017: Macromolecular Rapid Communications
Zubin Wang, Liping Heng, Lei Jiang
Aggregation-induced emission luminogens (AIEgens) have become an emerging field since the concept of AIE was proposed in 2001. Recently, AIEgens have attracted considerable attention due to their abnormal non-emissive fluorescent behavior in solution but strongly emissive behavior in the aggregate state. By utilizing the inherent hydrophobicity, AIEgens can be used to monitor the crystal formation and dewetting behavior in the self-assembly process. More importantly, some stimuli-responsive AIE-active surfaces have been successfully fabricated...
March 17, 2017: Macromolecular Rapid Communications
Susanne C Solleder, Rebekka V Schneider, Katharina S Wetzel, Andreas C Boukis, Michael A R Meier
This review describes different synthetic strategies towards sequence-defined, monodisperse macromolecules, which are built up by iterative approaches and lead to linear non-natural polymer structures. The review is divided in three parts: solution phase-, solid phase-, and fluorous- and polymer-tethered approaches. Moreover, synthesis procedures leading to conjugated and non-conjugated macromolecules are considered and discussed in the respective sections. A major focus in the evaluation is the applicability of the different approaches in polymer chemistry...
March 15, 2017: Macromolecular Rapid Communications
Ling Peng, Jian Zhu, Seema Agarwal
A tubular highly porous scaffold of polylactide (PLA) and poly-ε-caprolactone (PCL) is fabricated by self-rolling of a 2D fibrous bilayer of PLA and PCL in water without use of any classical thermo-/pH-responsive polymers. The self-rolling and diameter of the tube are dependent upon the bilayer thickness and temperature. A 75 µm thick 2D bilayer (PLA = 25 µm; PCL = 50 µm) rolls to a hollow tube of diameter around 0.41 mm with multilayered wall at 40 °C within 5 min. The tubes keep their form and size in water at all temperatures once they are formed...
March 15, 2017: Macromolecular Rapid Communications
Chen Hu, Mei Xiang Wang, Lei Sun, Jian Hai Yang, Miklós Zrínyi, Yong Mei Chen
Development of novel photoluminescent hydrogels with toughness, biocompatibility, and antibiosis is important for the applications in biomedical field. Herein, novel tough photoluminescent lanthanide (Ln)-alginate/poly(vinyl alcohol) (PVA) hydrogels with the properties of biocompatibility and antibiosis have been facilely synthesized by introducing hydrogen bonds and coordination bonds into the interpenetrating networks of Na-alginate and PVA, via approaches of frozen-thawing and ion-exchanging. The resultant hydrogels exhibit high mechanical strength (0...
March 15, 2017: Macromolecular Rapid Communications
Haoxuan Li, Chunlei Zhu, Jiajia Xue, Qinfei Ke, Younan Xia
This communication describes a simple and effective method for welding electrospun nanofibers at the cross points to enhance the mechanical properties of their nonwoven mats. The welding is achieved by placing a nonwoven mat of the nanofibers in a capped vial with the vapor of a proper solvent. For polycaprolactone (PCL) nanofibers, the solvent is dichloromethane (DCM). The welding can be managed in a controllable fashion by simply varying the partial pressure of DCM and/or the exposure time. Relative to the pristine nanofiber mat, the mechanical strength of the welded PCL nanofiber mat can be increased by as much as 200%...
March 10, 2017: Macromolecular Rapid Communications
Malte Winnacker, Jacob Sag, Andreas Tischner, Bernhard Rieger
A convenient synthesis of sustainable polyamides, which contain side groups and stereocenters, starting from the biobased small terpene β-pinene is reported. The polyamides, which are obtained via the pinene-based lactam via ring-opening polymerization, show excellent thermal properties, rendering this approach very interesting for the utilization of novel biobased and structurally significant high-performance polymers and materials. Polymer masses and yields are shown to be dependent on different parameters, and the stereoinformation of the lactam monomer can thus be transferred into the polymer chain...
March 8, 2017: Macromolecular Rapid Communications
Hongbo Wang, Hui Zhu, Weigui Fu, Yinyu Zhang, Bing Xu, Fei Gao, Zhiqiang Cao, Wenguang Liu
There is a significant cost to mitigate the infection and inflammation associated with the implantable medical devices. The development of effective antibacterial and anti-inflammatory biomaterials with novel mechanism of action has become an urgent task. In this study, a supramolecular polymer hydrogel is synthesized by the copolymerization of N-acryloyl glycinamide and 1-vinyl-1,2,4-triazole in the absence of any chemical crosslinker. The hydrogel network is crosslinked through the hydrogen bond interactions between dual amide motifs in the side chain of N-acryloyl glycinamide...
March 8, 2017: Macromolecular Rapid Communications
Giancarlo Galli, Elisa Martinelli
A range of amphiphilic polymers with diverse macromolecular architectures has been developed and incorporated into films and coatings with potential for marine antibiofouling applications, without resorting to addition of currently used biocidal, toxic agents. Novel "green" chemical technologies employ different building blocks to endow the polymer film with surface activity, functionality, structure, and reconstruction according to the outer environment as a result of a tailored amphiphilic character of the polymer platform...
March 7, 2017: Macromolecular Rapid Communications
Meiying Liu, Peng Gao, Qing Wan, Fengjie Deng, Yen Wei, Xiaoyong Zhang
Aggregation-induced emission (AIE) is an abnormal phenomenon that has sparked great attention for diverse applications in different fields. In particular, the fabrication and biological imaging applications of AIE-active fluorescent organic nanoparticles (FONs) have become a focus in the emerging and promising fields. A large number of AIE-active polymeric nanoprobes have recently been fabricated through different strategies. The advances and progress in this direction have also recently been summarized by some groups...
March 7, 2017: Macromolecular Rapid Communications
Haw-Lih Su, Dusan N Sredojevic, Hugo Bronstein, Tobin J Marks, Bob C Schroeder, Mohammed Al-Hashimi
The heterocyclic thiazole unit has been extensively used as electron-deficient building block in π-conjugated materials over the last decade. Its incorporation into organic semiconducting materials is particularly interesting due to its structural resemblance to the more commonly used thiophene building block, thus allowing the optoelectronic properties of a material to be tuned without significantly perturbing its molecular structure. Here, we discuss the structural differences between thiazole- and thiophene-based organic semiconductors, and the effects on the physical properties of the materials...
March 2, 2017: Macromolecular Rapid Communications
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