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Macromolecular Rapid Communications

Pratik Gurnani, Caroline P Bray, Robert A E Richardson, Raoul Peltier, Sébastien Perrier
Heparin plays a significant role in wound healing and tissue regeneration applications, through stabilization of fibroblast growth factors (FGF). Risks associated with batch-to-batch variability and contamination from its biological sources have led to the development of synthetic, highly sulfonated polymers as promising heparin mimics. In this work, a systematic study of an aqueous polymerization-induced self-assembly (PISA) of styrene from poly(2-acrylamido-2-methylpropane sodium sulfonate) (P(AMPS)) macro reversible addition-fragmentation chain transfer (macro-RAFT) agents produced a variety of spherical heparin-mimicking nanoparticles, which were further characterized with light scattering and electron microscopy techniques...
July 12, 2018: Macromolecular Rapid Communications
Yilong Cheng, Chaoliang He, Kaixuan Ren, Yan Rong, Chunsheng Xiao, Jianxun Ding, Xiuli Zhuang, Xuesi Chen
An advanced hydrogel that features facile formation and injectability as well as light-controlled degradation profile is reported here. By modifying 4-arm poly(ethylene glycol) (4-arm PEG) with 2-nitrobenzyl (NB) and phenol, the 4-arm PEG precursor solutions could form enzymatically cross-linked hydrogels in the presence of horseradish peroxidase (HRP) and hydrogen peroxide (H2 O2 ). The gelation time, mechanical strength, and porous structure could be simply tuned by the concentration of HRP and H2 O2 . Moreover, the hydrogels underwent controlled degradation under UV light irradiation via photo-cleavage reaction of the NB ester bond...
July 12, 2018: Macromolecular Rapid Communications
Xuan Liu, Zibiao Li, Xian Jun Loh, Kaifeng Chen, Zhen Li, Yun-Long Wu
Coadministration of chemotherapeutics as well as therapeutic gene could play a synergistic effect on cancer treatment. It is noteworthy that targeted and sustained codelivery of chemotherapeutic and therapeutic gene was rarely achieved in previous reports, while it might serve as an important platform for treating solid tumor with possible surrounding lesions. Herein, an injectable supramolecular hydrogel formed by α-cyclodextrin (α-CD) and cationic amphiphilic copolymer made of methoxy-poly(ethylene glycol)-b-poly(ε-caprolactone)-b-poly(ethylene imine) with folic acid targeted group (MPEG-PCL-PEI-FA), is rationally designed to achieve sustained codelivery of chemotherapeutic paclitaxel (PTX) and B-cell lymphoma-2 (Bcl-2) conversion gene Nur77 in the form of nanocomplex up to 7 days, to effectively inhibit the growth of folate receptor overexpressing H460/Bcl-2 therapeutic-resistant tumors (induced by overexpression of anti-apoptotic Bcl-2 protein), with peritumoral injection rather than direct intratumoral injection of hydrogel...
July 10, 2018: Macromolecular Rapid Communications
Or Galant, Maya Davidovich-Pinhas, Charles E Diesendruck
The conformation of a polymer in a solvent is typically defined by the solvent quality, which is a consequence of the solvent and macromolecule's chemistry. Yet, additional factors can affect the polymer conformation, such as non-covalent interactions to surfaces or other macromolecules, affecting the amount of polymer-solvent interactions. Herein, chemically folded polymers with protein-like architectures are studied and compared to their unfolded linear precursor in good solvents using rheology measurements...
July 8, 2018: Macromolecular Rapid Communications
Shamila Firdaus, Martin Geisler, Peter Friedel, Susanta Banerjee, Dietmar Appelhans, Brigitte Voit, Albena Lederer
Molar mass and end group number of a hyperbranched polyester are significantly increased by its transformation to a pseudodendrimer. Three generations of pseudodendrimers are obtained from hyperbranched aliphatic polyester core by modification with a protected AB*2 monomer. A sequence of protection and deprotection steps leads to OH-terminated pseudodendrimers. NMR studies confirm maximum degree of branching in the first generation, which slightly decreases in the next two generations. Uniform, dense molecular structure formation was confirmed by MD simulation...
July 8, 2018: Macromolecular Rapid Communications
Jiajia Zhang, Guangjie Song, Lin Qiu, Yanhui Feng, Jie Chen, Jie Yan, Liyao Liu, Xing Huang, Yutao Cui, Yimeng Sun, Wei Xu, Daoben Zhu
Polythiophene (PTh) with highly regular molecular structure is synthesized as nearly amorphous thin films by electrochemical methods in a BFEE/DTBP mixed medium (BFEE = boron fluoride ethyl ether; DTBP = 2,6-di-tert-butypyridine). The doping level and film morphology of PTh are modulated through adjusting the current density applied during the polymerization process. A combined analysis with solid-state NMR, FT-IR, and Raman spectra reveals the molecular structural regularity of the resulted PTh films, which leads to the highest electrical conductivity up to 700 S cm-1 for films obtained under an optimized current density of 1 mA cm-2 ...
July 5, 2018: Macromolecular Rapid Communications
Suyeong An, Hyun Jin Kim, Sangwon Chi, Jonghwi Lee
Silicone-based polymers have been widely used for many applications, but their extremely low surface energies and the resulting poor adhesion have been the cause for continuous problems. Herein, a novel adhesion improvement technique using an interlocked finger structure is demonstrated, which enables up to 24.8 and 7.3-fold increases in adhesion compared to the untreated and conventional plasma-treated cases, respectively. The interlocked finger structure is fabricated by surface-confined dissolution and subsequent directional melt crystallization of a solvent...
July 4, 2018: Macromolecular Rapid Communications
Nicolas Busatto, Vlad Stolojan, Michael Shaw, Joseph L Keddie, Peter J Roth
The use of 2,3,4,5,6-pentafluorobenzyl methacrylate (PFBMA) as a core-forming monomer in ethanolic reversible addition-fragmentation chain transfer dispersion polymerization formulations is presented. Poly[poly(ethylene glycol) methyl ether methacrylate] (pPEGMA) macromolecular chain transfer agents were chain-extended with PFBMA leading to nanoparticle formation via polymerization-induced self-assembly (PISA). pPEGMA-pPFBMA particles exhibited the full range of morphologies (spheres, worms, and vesicles), including pure and mixed phases...
July 4, 2018: Macromolecular Rapid Communications
Sella Kurnia Putri, Yun Hwan Kim, Dong Ryeol Whang, Joo Hyun Kim, Dong Wook Chang
A series of quinoxaline-based conjugated polymers, in which the electron-donating benzodithiophene (BDT) unit is linked to the electron-accepting 6,7-difluorinated quinoxaline (DFQ) derivatives by a thiophene bridge, is synthesized. To investigate their effects on the intrinsic properties of polymers, strong electron-withdrawing trifluoromethyl (CF3 ) groups were incorporated into the meta-position of the phenyl ring at the 2,3-positions of the DFQ unit of the reference polymer, labelled PEhB-FQx, to yield the target polymer PEhB-FQxCF3...
July 4, 2018: Macromolecular Rapid Communications
Laura A Lanier, Harry Bermudez
Recently there have been notable synthetic successes in supramolecular polymerization. By contrast, it has long been known that DNA can undergo supramolecular polymerization (concatemerization). Concatemerization is a step-like polymerization and consequently suffers from broad molecular weight distributions and generally undesirable cyclization reactions. Here we demonstrate that another supramolecular polymerization of DNA, hybridization chain reaction (HCR), is in fact a living polymerization. After consumption of initial monomer, the polymerization can be continued with further addition of monomer, and the molecular weight can be varied by the ratio of monomer to initiator...
July 4, 2018: Macromolecular Rapid Communications
Xiao Wang, Zesheng An
Polymerization-induced self-assembly (PISA) has been established as an efficient, robust, and versatile approach to synthesize various block copolymer nano-objects with controlled morphologies, tunable dimensions, and diverse functions. The relatively high concentration and potential scalability makes it a promising technique for industrial production and practical applications of functional polymeric nanoparticles. This feature article outlines recent advances in PISA via reversible addition-fragmentation chain transfer dispersion polymerization...
July 4, 2018: Macromolecular Rapid Communications
Yaoming Zhang, Zongyu Wang, Krzysztof Matyjaszewski, Joanna Pietrasik
The evolution of particle morphology occurring during polymerization-induced self-assembly (PISA) of a block copolymer poly(oligo(ethylene glycol) methacrylate)-b-poly(benzyl methacrylate) (POEGMA-b-PBzMA) is studied. A well-controlled reversible addition-fragmentation chain transfer (RAFT) polymerization yields nano-objects with various morphologies: spheres, aggregates, worm-like structures, and vesicles. A comparison of the morphology of the nano-objects formed from two different chain-length stabilizers established that the unreacted monomer played an important role during the morphology transitions, which is contrary to previous observations...
July 4, 2018: Macromolecular Rapid Communications
Haifei Wang, Ziya Wang, Jian Yang, Chen Xu, Qi Zhang, Zhengchun Peng
Ionic gels represent a novel class of stretchable materials where ionic conducting liquid is immobilized in a polymer matrix. This review focuses on the design of ionic gel materials and device fabrication of ionic-gel-based stretchable electronics. In particular, recent progress in ionic-gel-based electronic skin (pressure/strain sensors, electric double-layer transistors, etc.), flexible displays, energy storage devices, and soft actuators are summarized, followed by a discussion of challenges in developing ionic-gel-based electronics and suggestions for future research directions that might overcome those challenges...
July 3, 2018: Macromolecular Rapid Communications
Wen-Jian Zhang, Chun-Yan Hong, Cai-Yuan Pan
Drug delivery systems (DDS) based on functionalized polymeric nanoparticles have attracted considerable attention. Although great advances have been reported in the past decades, the fabrication efficiency and reproducibility of polymeric nanoparticles are barely satisfactory due to the intrinsic limitations of the traditional self-assembly method, which severely prevent further applications of the intelligent DDS. In the last decade, a new self-assembly method, which is usually called polymerization-induced self-assembly (PISA), has become a powerful strategy for the fabrication of the polymeric nanoparticles with bespoke morphology...
July 2, 2018: Macromolecular Rapid Communications
Zhiqing Zhang, Hongzhi Zhang, Fang Wang, Guodong Zhang, Ting Zhou, Xiufeng Wang, Shuzhen Liu, Tingting Liu
A simplified origami strategy to create large-scale complex DNA nanostructures based on the rolling circle amplification (RCA) is developed. The long repetitive block single strand DNA (ssDNA) synthesized from RCA with a few staple strands are used to fabricate DNA origami, which can be assembled into the first level assemblies of micro-scale length mono-nanoladders. Depending on base pairing among the sticky ends of short staple strands in nanoladders, the second level assemblies with large-scale and controlled structures such as tri-nanoladder, penta-nanoladder, and even nanobrocade, can be further achieved...
June 27, 2018: Macromolecular Rapid Communications
Bin He, Xing Zhu, Changwen Zhao, Guan Wang, Yuhong Ma, Wantai Yang
Entrapment of living cells into a polymer network has significant potential in various fields such as biomass conversion and tissue engineering. A crucial challenge for this strategy is to provide a mild enough condition to preserve cell viability. Here, a facile and cytocompatible method to entrap living yeast cells into a poly(ethylene glycol) (PEG) network grafting from polypropylene nonwoven fabrics via visible-light-induced surface living graft crosslinking polymerization is reported. Due to the mild reaction conditions and excellent biocompatibility of PEG, the immobilized yeast cells could maintain their viability and proliferate well...
June 26, 2018: Macromolecular Rapid Communications
Jian Wang, Zhigang Wu, Guowei Wang, Krzysztof Matyjaszewski
Polymerization-induced self-assembly (PISA) and in situ crosslinking of the formed nanoparticles are successfully realized by activators regenerated by electron-transfer atom transfer radical polymerization (ARGET ATRP) of glycidyl methacrylate (GMA) or a mixture of GMA/benzyl methacrylate (BnMA) monomers in ethanol. Poly(oligo(ethylene oxide) methyl ether methacrylate) was employed as macroinitiator/stabilizer, and a cupric bromide/tris(pyridin-2-ylmethyl)amine complex as catalyst. Tin (2-ethylhexanoate) was used as reducing agent for ARGET ATRP, and simultaneously acted as a catalyst for ring-opening polymerization of oxirane ring in GMA...
June 26, 2018: Macromolecular Rapid Communications
Hatice Turgut, Divya Varadharajan, Nico Dingenouts, Guillaume Delaittre
A library of poly(methyl methacrylate)-block-polystyrene (PMMA-b-PS) block copolymers (BCPs) bearing small amounts (<10 mol%) of functional comonomer in either one or both blocks is investigated for their phase separation behavior in bulk and in thin films. Particularly, functionalities typically involved in modern postpolymerization modifications are considered, e.g., azide, pentafluorophenyl, furfuryl. Small-angle X-ray scattering and atomic force microscopy are employed to determine the characteristic dimensional features of lamellae-forming BCPs, which differ essentially in the functional groups...
June 26, 2018: Macromolecular Rapid Communications
Jun He, Qin Xu, Jianbo Tan, Li Zhang
Herein, ketone-functionalized diblock copolymer nano-objects are prepared by photoinitiated reversible addition-fragmentation chain transfer (RAFT) dispersion polymerization of tert-butyl acrylate (tBA) using a poly(diacetone acrylamide) (PDAAM)-based macromolecular RAFT (macro-RAFT) agent in ethanol/water (60/40, w/w) at room temperature. A high polymerization rate is observed via the exposure of visible light (λmax = 405 nm, 0.45 mW cm-2 ) with near quantitative monomer conversion being achieved within 60 min...
June 26, 2018: Macromolecular Rapid Communications
Csilla György, Joseph R Lovett, Nicholas J W Penfold, Steven P Armes
Polymerization-induced self-assembly (PISA) is a powerful and versatile technique for the synthesis of a wide range of sterically stabilized diblock copolymer nano-objects. Recently, PISA has been used to prepare epoxy-functional diblock copolymer worms and spheres directly in aqueous solution by incorporating glycidyl methacrylate (GlyMA) into the core-forming hydrophobic block. Herein, the synthesis of diblock copolymer spheres via reversible addition-fragmentation chain transfer (RAFT) aqueous emulsion polymerization of benzyl methacrylate is examined, in which the epoxy groups are exclusively located within a non-ionic poly(glycerol monomethacrylate)-based stabilizer block...
June 25, 2018: Macromolecular Rapid Communications
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