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You searched for: Journal name Macromolecules Remove constraint Journal name: Macromolecules Publication year rev 7983-2017 Remove constraint Publication year rev: 7983-2017 Source 2017 v.50 no.3 Remove constraint Source: 2017 v.50 no.3
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1. Anisotropic Three-Particle Interactions between Spherical Polymer-Grafted Nanoparticles in a Polymer Matrix

Author:
Tang Tsung-Yeh; Arya Gaurav
Source:
Macromolecules 2017 v.50 no.3 pp. 1167-1183
ISSN:
1520-5835
Subject:
anisotropy; isotropy; molecular dynamics; nanoparticles; physical phases; polymers; simulation models
Abstract:
... Spherical nanoparticles (NPs) uniformly grafted with polymer chains have recently been shown to assemble into anisotropic phases like strings and sheets. Here we investigated the underlying basis for anisotropic interactions between polymer-grafted NPs in a polymer matrix by computing via molecular dynamics simulations the potential of mean force (PMF), and its three-body contribution, for a test ...
DOI:
10.1021/acs.macromol.6b01936

2. Chromogenic Tubular Polydiacetylenes from Topochemical Polymerization of Self-Assembled Macrocyclic Diacetylenes

Author:
Heo Jung-Moo; Kim Youngmee; Han Seulki; Joung Joonyoung F.; Lee Sang-hwa; Han Sejin; Noh Jaegeun; Kim Jaeyong; Park Sungnam; Lee Haiwon; Choi Yoon Mi; Jung Young-Sik; Kim Jong-Man
Source:
Macromolecules 2017 v.50 no.3 pp. 900-913
ISSN:
1520-5835
Subject:
chemical bonding; colorimetry; crystal structure; geometry; models; nanotubes; polymerization; solvents; xylene
Abstract:
... Tubular materials formed by self-assembly of small organic molecules find great utility in chemical and material science. Conventional tubular structures often lack stability because noncovalent molecular interactions are responsible for their conformational integrities. Herein we report the development of covalently linked chromogenic organic nanotubes which are prepared by using topochemical pol ...
DOI:
10.1021/acs.macromol.6b02493

3. Conformation and Dynamics of Individual Star in Shear Flow and Comparison with Linear and Ring Polymers

Author:
Chen Wenduo; Zhang Kexin; Liu Lijun; Chen Jizhong; Li Yunqi; An Lijia
Source:
Macromolecules 2017 v.50 no.3 pp. 1236-1244
ISSN:
1520-5835
Subject:
deformation; molecular dynamics; polymers; rheological properties; rheology; shear stress; simulation models
Abstract:
... How polymers with different architectures respond to shear stress is a key issue to develop a fundamental understanding of their dynamical behaviors. We investigate the conformation, orientation, dynamics, and rheology of individual star polymers in a simple shear flow by multiparticle collision dynamics integrated with molecular dynamics simulations. Our studies reveal that star polymers present ...
DOI:
10.1021/acs.macromol.6b02636

4. Designing Sequence-Specific Copolymer Compatibilizers Using a Molecular-Dynamics-Simulation-Based Genetic Algorithm

Author:
Meenakshisundaram Venkatesh; Hung Jui-Hsiang; Patra Tarak K.; Simmons David S.
Source:
Macromolecules 2017 v.50 no.3 pp. 1155-1166
ISSN:
1520-5835
Subject:
algorithms; composite polymers; emulsions; energy; models; thermodynamics
Abstract:
... Compatibilizerssurfactant molecules designed to improve the stability of an interfaceare employed to enhance material properties in settings ranging from emulsions to polymer blends. A major compatibilization strategy employs block or random copolymers composed of distinct repeat units with preferential affinity for each of the two phases forming the interface. Here we pose the question of wheth ...
DOI:
10.1021/acs.macromol.6b01747

5. Effect of Confinement on the Synthesis of PMMA in AAO Templates and Modeling of Free Radical Polymerization

Author:
Sanz Belén; Ballard Nicholas; Asua José M.; Mijangos Carmen
Source:
Macromolecules 2017 v.50 no.3 pp. 811-821
ISSN:
1520-5835
Subject:
aluminum oxide; free radicals; mathematical models; molecular weight; polymerization; polymethylmethacrylate
Abstract:
... The hierarchical surface structure of polymer materials leads to unique properties which are of both academic and commercial interest. In this work we explore the ability to replicate the well-defined surface structure of anodic aluminum oxide (AAO) templates by in situ polymerization of methyl methacrylate. When the reaction is conducted inside the templates, the rate of polymerization was signif ...
DOI:
10.1021/acs.macromol.6b02282

6. Effect of Short Chain Branching on the Interlamellar Structure of Semicrystalline Polyethylene

Author:
Kumar Vaibhaw; Locker C. Rebecca; in ’t Veld Pieter J.; Rutledge Gregory C.
Source:
Macromolecules 2017 v.50 no.3 pp. 1206-1214
ISSN:
1520-5835
Subject:
crystallites; models; molecular dynamics; polyethylene; thermodynamics; topology
Abstract:
... We use molecular simulations with a united atom force field to examine the effect of short chain branching (SCB) on the noncrystalline, interlamellar structure typical of linear low density polyethylene (LLDPE). The model is predicated on a metastable thermodynamic equilibrium within the interlamellar space of the crystal stack and accounts explicitly for the various chain topologies (loops, tails ...
DOI:
10.1021/acs.macromol.6b02458

7. Efficient Synthesis of Fluorinated Phenanthrene Monomers Using Mallory Reaction and Their Copolymerization

Author:
Fukumoto Hiroki; Ando Masatoshi; Shiota Tomomi; Izumiya Hirokazu; Kubota Toshio
Source:
Macromolecules 2017 v.50 no.3 pp. 865-871
ISSN:
1520-5835
Subject:
Suzuki reaction; chloroform; composite polymers; condensation reactions; copolymerization; iodides; irradiation; phenanthrenes; wavelengths
Abstract:
... The Mallory reaction of 1,2-diarylhexafluorocyclopentene (1, aryl = 3-bromophenyl; 2, aryl = 4-bromophenyl) under light irradiation (λ = 365 nm) in the presence of iodide proceeded to give dibromophenanthrene derivatives, 3 and 4. Polycondensation of 9,9-dioctylfluorene-2,7-diboronic acid bis(1,3-propanediol)ester with the obtained monomers by Suzuki–Miyaura coupling afforded the phenanthrene-type ...
DOI:
10.1021/acs.macromol.6b02151

8. Insights into the Vulcanization Mechanism through a Simple and Facile Approach to the Sulfur Cleavage Behavior

Author:
Lian Qingsong; Li Yan; Li Kai; Cheng Jue; Zhang Junying
Source:
Macromolecules 2017 v.50 no.3 pp. 803-810
ISSN:
1520-5835
Subject:
Fourier transform infrared spectroscopy; anions; epoxides; free radicals; heterolytic cleavage; homolytic cleavage; models; moieties; rubber; sulfur; thiols
Abstract:
... The vulcanization mechanism remains unclear due to the difficulty of characterization and the complexity of the vulcanization systems. In this work, a series of epoxy model systems were used to study the sulfur cleavage behavior, from which the study process of the vulcanization mechanism was significantly simplified and a brand new sulfur-only vulcanization mechanism was revealed by the FTIR and ...
DOI:
10.1021/acs.macromol.6b02335

9. Ion-Pairing Strength in Polyelectrolyte Complexes

Author:
Fu Jingcheng; Fares Hadi M.; Schlenoff Joseph B.
Source:
Macromolecules 2017 v.50 no.3 pp. 1066-1074
ISSN:
1520-5835
Subject:
Gibbs free energy; diffusivity; electrolytes; nanoparticles; polymers; potassium bromide; primary amines; sodium chloride; sulfonates; water content
Abstract:
... Polyelectrolyte complexes, PECs, are spontaneously formed blends of polyelectrolytes bearing positive, Pol⁺, and negative, Pol–, repeat units. Many interesting PEC morphologies have been observed, ranging from dense precipitates to liquidlike coacervates to quasi-stable nanoparticles, depending on the identity of the polymers and the preparation conditions. While the number of polyelectrolytes ava ...
DOI:
10.1021/acs.macromol.6b02445

10. Lateral Structure Formation in Polyelectrolyte Brushes Induced by Multivalent Ions

Author:
Brettmann Blair; Pincus Philip; Tirrell Matthew
Source:
Macromolecules 2017 v.50 no.3 pp. 1225-1235
ISSN:
1520-5835
Subject:
colloids; energy balance; ions; micelles; polymers; solvents; theoretical models
Abstract:
... We provide a theoretical model for the collapse of polyelectrolyte brushes in the presence of multivalent ions, focusing on the formation of lateral inhomogeneties in the collapsed state. Polyelectrolyte brushes are important in a variety of applications, including stabilizing colloidal particles and lubricating surfaces. Many uses rely on the extension of the densely grafted polymer chains from t ...
DOI:
10.1021/acs.macromol.6b02563

11. Mechanical Behaviors of Highly Swollen Supramolecular Hydrogels Mediated by Pseudorotaxanes

Author:
Li Zhiqiang; Zhang Ying-Ming; Wang Huan-Yu; Li Huanrong; Liu Yu
Source:
Macromolecules 2017 v.50 no.3 pp. 1141-1146
ISSN:
1520-5835
Subject:
hydrogels; laponite; molecular weight; strength (mechanics); water content
Abstract:
... Supramolecular self-assemblies based on multiple noncovalent forces have emerged as an effective way to fabricate multistimuli-responsive and self-healable intelligent materials. However, the development of supramolecular nanostructures as advanced functional materials in practical fields is always subjected to their relatively weaker mechanical strength and overuse of organic components. In this ...
DOI:
10.1021/acs.macromol.6b02459

12. Mixed-Ligand Approach to Palladium-Catalyzed Direct Arylation Polymerization: Highly Selective Synthesis of π-Conjugated Polymers with Diketopyrrolopyrrole Units

Author:
Wakioka Masayuki; Takahashi Rina; Ichihara Nobuko; Ozawa Fumiyuki
Source:
Macromolecules 2017 v.50 no.3 pp. 927-934
ISSN:
1520-5835
Subject:
arylation; catalysts; catalytic activity; composite polymers; crosslinking; ligands; molecular weight; optical properties; polymerization; toluene
Abstract:
... The combined use of P(2-MeOC₆H₄)₃ (L1) and TMEDA as ligands effectively prevents defect formation in palladium-catalyzed direct arylation polymerization (DArP) to give donor–acceptor type alternating copolymers (DA polymers) with diketopyrrolopyrrole (DPP) units. The reaction of 3,6-bis(5-bromo-2-thienyl)diketopyrrolopyrrole (1-Br) and 3,4-dicyanothiophene (2-H) in toluene at 100 °C for 6 h in the ...
DOI:
10.1021/acs.macromol.6b02679

13. Molecular Doping of a High Mobility Diketopyrrolopyrrole–Dithienylthieno[3,2-b]thiophene Donor–Acceptor Copolymer with F6TCNNQ

Author:
Karpov Yevhen; Erdmann Tim; Stamm Manfred; Lappan Uwe; Guskova Olga; Malanin Mikhail; Raguzin Ivan; Beryozkina Tetyana; Bakulev Vasiliy; Günther Florian; Gemming Sibylle; Seifert Gotthard; Hambsch Mike; Mannsfeld Stefan; Voit Brigitte; Kiriy Anton
Source:
Macromolecules 2017 v.50 no.3 pp. 914-926
ISSN:
1520-5835
Subject:
absorption; composite polymers; density functional theory; thiophene
Abstract:
... Herein we present a molecular doping of a high mobility diketopyrrolopyrrole–dithienylthieno[3,2-b]thiophene donor–acceptor copolymer poly[3,6-(dithiophene-2-yl)-2,5-di(6-dodecyloctadecyl)pyrrolo[3,4-c]pyrrole-1,4-dione-alt-thieno[3,2-b]thiophene], PDPP(6-DO)₂TT, with the electron-deficient compound hexafluorotetracyanonaphthoquinodimethane (F6TCNNQ). Despite a slightly negative HOMOdₒₙₒᵣ–LUMOₐccₑ ...
DOI:
10.1021/acs.macromol.6b02452

14. Morphological Evolution of Ionomer/Plasticizer Mixtures during a Transition from Ionomer to Polyelectrolyte

Author:
Zhang Zhijie; Liu Chang; Cao Xiao; Wang Jing-Han Helen; Chen Quan; Colby Ralph H.
Source:
Macromolecules 2017 v.50 no.3 pp. 963-971
ISSN:
1520-5835
Subject:
X-ray scattering; dielectric properties; ions; liquids; plasticizers; polymers; sodium; styrene; temperature
Abstract:
... X-ray scattering data were used to examine the morphological evolution that accompanies the ionomer-to-polyelectrolyte transition. Bulk random ionomer based on methacryl diglyme side chains and sodium sulfonated styrene exhibits an amorphous halo, a backbone correlation peak, and an ionic aggregate spacing peak in X-ray scattering. The ionic peak intensifies as either polymer content or temperatur ...
DOI:
10.1021/acs.macromol.6b02225

15. Multi-Scale Assembly of Polythiophene-Surfactant Supramolecular Complexes for Charge Transport Anisotropy

Author:
Bilger David; Sarkar Amrita; Danesh Cameron; Gopinadhan Manesh; Braggin Gregory; Figueroa Jose; Pham Thanh Vy; Chun Danielle; Rao Yashas; Osuji Chinedum O.; Stefik Morgan; Zhang Shanju
Source:
Macromolecules 2017 v.50 no.3 pp. 1047-1055
ISSN:
1520-5835
Subject:
absorption; anisotropy; electrolytes; fluorescence emission spectroscopy; ionic surfactants; light microscopy; liquids; microstructure; polymers; small-angle X-ray scattering; spectral analysis
Abstract:
... Multiscale assembly of poly(3-alkylthiophene)s complexed with various alkyl-chain surfactant architectures has been investigated in dilute and concentrated solutions by means of ultraviolet–visible absorption and fluorescence spectroscopy, polarized optical microscopy, small-angle X-ray scattering, and four-point probe conductivity measurements. Supramolecular complexation occurs via ionic interac ...
DOI:
10.1021/acs.macromol.6b02416

16. Nanoscale Structure and Morphology of Sulfonated Polyphenylenes via Atomistic Simulations

Author:
Abbott Lauren J.; Frischknecht Amalie L.
Source:
Macromolecules 2017 v.50 no.3 pp. 1184-1192
ISSN:
1520-5835
Subject:
algorithms; hydrophilicity; ions; nanomaterials; water content
Abstract:
... We performed atomistic simulations on a series of sulfonated polyphenylenes systematically varying the degree of sulfonation and water content to determine their effect on the nanoscale structure, particularly for the hydrophilic domains formed by the ionic groups and water molecules. We found that the local structure around the ionic groups depended on the sulfonation and hydration levels, with t ...
DOI:
10.1021/acs.macromol.6b02232

17. Naphthodithiophenediimide–Benzobisthiadiazole-Based Polymers: Versatile n-Type Materials for Field-Effect Transistors and Thermoelectric Devices

Author:
Wang Yang; Nakano Masahiro; Michinobu Tsuyoshi; Kiyota Yasuhiro; Mori Takehiko; Takimiya Kazuo
Source:
Macromolecules 2017 v.50 no.3 pp. 857-864
ISSN:
1520-5835
Subject:
chemical interactions; electrical properties; electron transfer; energy; films (materials); moieties; polymers; solubilization; transistors; ultraviolet-visible spectroscopy
Abstract:
... New π-conjugated polymers with strong electron affinity, PNDTI-BBTs, consisting of naphtho[2,3-b:6,7-b′]dithiophenediimide (NDTI) and benzo[1,2-c:4,5-c′]bis[1,2,5]thiadiazole (BBT) units, were synthesized. PNDTI-BBTs have low-lying LUMO energy levels (∼−4.4 eV), which is sufficiently low for air-stable electron transport in organic field-effect transistors and for being readily doped by a well-kno ...
DOI:
10.1021/acs.macromol.6b02313

18. Perfectly Alternating Ethylene/2-Butene Copolymers by Hydrogenation of Highly Stereoregular 1,4-Poly(1,3-diene)s: Synthesis and Characterization

Author:
Ricci Giovanni; Leone Giuseppe; Boccia Antonella Caterina; Pierro Ivana; Zanchin Giorgia; Mauri Massimiliano; Scoti Miriam; Malafronte Anna; Auriemma Finizia; De Rosa Claudio
Source:
Macromolecules 2017 v.50 no.3 pp. 754-761
ISSN:
1520-5835
Subject:
X-radiation; composite polymers; hydrazides; hydrogenation; imines; isoprene; ligands; nuclear magnetic resonance spectroscopy; olefin; polymerization; rare earth elements
Abstract:
... In recent years it has been introduced a new generation of complexes of transition metals and lanthanides with various ligands containing donor atoms such as P, N, and O (e.g., phosphines, imines, iminopyridines, and ketoimines) that, in combination with MAO, give highly stereoregular polymers (cis-1,4, iso- and syndiotactic; 1,2, iso- and syndiotactic) from various substituted butadienes (i.e., i ...
DOI:
10.1021/acs.macromol.6b02165

19. Photoregulated Cross-Linking of Superparamagnetic Iron Oxide Nanoparticle (SPION) Loaded Hybrid Nanovectors with Synergistic Drug Release and Magnetic Resonance (MR) Imaging Enhancement

Author:
Zhu Kangning; Deng Zhengyu; Liu Guhuan; Hu Jinming; Liu Shiyong
Source:
Macromolecules 2017 v.50 no.3 pp. 1113-1125
ISSN:
1520-5835
Subject:
cetyltrimethylammonium bromide; composite polymers; crosslinking; cytotoxicity; doxorubicin; emulsions; evaporation; hydrophobicity; image analysis; magnetic materials; magnetic resonance imaging; magnetism; nanoparticles; oleic acid; photosensitivity; polyethylene glycol; polymerization; solvents; ultraviolet radiation
Abstract:
... The development of stimuli-responsive magnetic resonance imaging (MRI) contrast agents that can selectively enhance imaging contrasts at pathological sites is of potential use in clinical diagnosis. Herein, a T₂-type MRI contrast agent with synergistically photoregulated enhanced MRI contrast and drug release was achieved by coassembly of superparamagnetic iron oxide nanoparticles (SPIONs) and dox ...
DOI:
10.1021/acs.macromol.6b02162

20. Polymer Assemblies with Nanostructure-Correlated Aggregation-Induced Emission

Author:
Huo Meng; Ye Qiquan; Che Hailong; Wang Xiaosong; Wei Yen; Yuan Jinying
Source:
Macromolecules 2017 v.50 no.3 pp. 1126-1133
ISSN:
1520-5835
Subject:
benzene; fluorescence; micelles; nanomaterials; polymers
Abstract:
... The correlation of aggregation-induced emission (AIE) to the nanostructure of polymer assemblies was investigated. A series of AIE-active PDMA-b-P(BzMA-TPE) [PDMA: poly(N,N-dimethylaminoethyl methacrylate); P(BzMA-TPE): poly[benzyl methacrylate-co-1-ethenyl-4-(1,2,2-triphenylethenyl)benzene]] assemblies with controlled nanostructures were prepared via polymerization-induced self-assembly of BzMA a ...
DOI:
10.1021/acs.macromol.6b02499