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You searched for: Journal Macromolecules Remove constraint Journal: Macromolecules Publication Year 2016 Remove constraint Publication Year: 2016 Source 2016 v.49 no.22 Remove constraint Source: 2016 v.49 no.22
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1. All-Aromatic (AB)n-Multiblock Copolymers via Simple One-Step Melt Condensation Chemistry

Author:
Guan, Qingbao; Norder, Ben; Chu, Liangyong; Besseling, Nicolaas A. M.; Picken, Stephen J.; Dingemans, Theo J.
Source:
Macromolecules 2016 v.49 no.22 pp. 8549-8562
ISSN:
1520-5835
Subject:
4-hydroxybenzoic acid; atomic force microscopy; composite polymers; crosslinking; glass transition temperature; heat treatment; isotropy; liquid crystals; melting; polymerization; scanning electron microscopy; separation; texture; transesterification
Abstract:
... We have prepared (AB)ₙ-multiblock copolymers based on N-(3′-hydroxyphenyl)trimellitimide (IM), 4-hydroxybenzoic acid (HBA), and 6-hydroxy-2-naphthoic acid (HNA) via a simple one-pot melt condensation method. The blocky nature is the result of phase separation taking place in the early stages of the melt polymerization process. The liquid crystal HBA/HNA fraction phase separates from the isotropic ...
DOI:
10.1021/acs.macromol.6b01341

2. A Metal Salt Dependent Self-Healing Response in Supramolecular Block Copolymers

Author:
Enke, Marcel; Bose, Ranjita K.; Bode, Stefan; Vitz, Jürgen; Schacher, Felix H.; Garcia, Santiago J.; van der Zwaag, Sybrand; Hager, Martin D.; Schubert, Ulrich S.
Source:
Macromolecules 2016 v.49 no.22 pp. 8418-8429
ISSN:
1520-5835
Subject:
chlorides; composite polymers; crosslinking; ligands; manganese; polymerization; polystyrenes; rheological properties
Abstract:
... Different block copolymers containing terpyridine were synthesized applying the reversible addition–fragmentation chain transfer (RAFT) polymerization. The block copolymers contain polystyrene as hard block, and the soft block consists of n-butyl acrylate (BA) as well as terpyridine units as ligand. These block copolymers were further cross-linked with several metal salts in order to tune the self ...
DOI:
10.1021/acs.macromol.6b02108

3. Anisotropic Nonlinear Mechanical Behavior in Carbon Nanotubes/Poly(1,4-cis-isoprene) Nanocomposites

Author:
Agnelli, Silvia; Pandini, Stefano; Serafini, Andrea; Musto, Sara; Galimberti, Maurizio
Source:
Macromolecules 2016 v.49 no.22 pp. 8686-8696
ISSN:
1520-5835
Subject:
anisotropy; carbon nanotubes; compression molding; energy; isotropy; mechanical properties; mixing; polymer nanocomposites; transmission electron microscopy
Abstract:
... This work shows the remarkable anisotropic nonlinear mechanical behavior of nanocomposites based on carbon nanotubes and poly(1,4-cis-isoprene), prepared by mechanical mixing, calendering, and compression molding. The dynamic-mechanical moduli were measured as a function of the applied strain and along specific directions. The specimens revealed, at all filler contents, an orthotropic and transver ...
DOI:
10.1021/acs.macromol.6b01682

4. A Novel Bis-Lactam Acceptor with Outstanding Molar Extinction Coefficient and Structural Planarity for Donor–Acceptor Type Conjugated Polymer

Author:
Yoon, Won Sik; Kim, Dong Won; Park, Jun-Mo; Cho, Illhun; Kwon, Oh Kyu; Whang, Dong Ryeol; Kim, Jin Hong; Park, Jung-Hwa; Park, Soo Young
Source:
Macromolecules 2016 v.49 no.22 pp. 8489-8497
ISSN:
1520-5835
Subject:
absorption; electrochemistry; energy; polymers; solar cells
Abstract:
... A novel electron-accepting bis-lactam building block, 3,7-dithiophen-2-yl-1,5-dialkyl-1,5-naphthyridine-2,6-dione (NTDT), and a conjugated polymer P(NTDT-BDT) comprising NTDT as an electron acceptor and benzo[1,2-b:4,5-b′]dithiophene (BDT) as an electron donor are designed and synthesized for producing efficient organic solar cells. The thermal, electronic, photophysical, electrochemical, and stru ...
DOI:
10.1021/acs.macromol.6b01680

5. Assembly of Amphiphilic Hyperbranched Polymeric Ionic Liquids in Aqueous Media at Different pH and Ionic Strength

Author:
Korolovych, Volodymyr F.; Ledin, Petr A.; Stryutsky, Alexandr; Shevchenko, Valery V.; Sobko, Oleh; Xu, Weinan; Bulavin, Leonid A.; Tsukruk, Vladimir V.
Source:
Macromolecules 2016 v.49 no.22 pp. 8697-8710
ISSN:
1520-5835
Subject:
aggregation behavior; hydrophilicity; hydrophobicity; ionic liquids; ionic strength; ionization; micelles; neutralization; pH; polyesters; triazoles
Abstract:
... We demonstrated the assembly of amphiphilic hyperbranched protic ionic liquids (HBP-ILs) based on aliphatic hyperbranched polyester (HBP) in aqueous media in a wide range of pH and ionic conditions. The series of new branched polyionic liquids with different terminal groups, HBP-ILs, was synthesized by neutralization of carboxylic and sulfonic terminal acid groups of hypebranched core with N-methy ...
DOI:
10.1021/acs.macromol.6b01562

6. Bioinspired Engineering of Two Different Types of Sacrificial Bonds into Chemically Cross-Linked cis-1,4-Polyisoprene toward a High-Performance Elastomer

Author:
Liu, Jie; Wang, Sheng; Tang, Zhenghai; Huang, Jing; Guo, Baochun; Huang, Guangsu
Source:
Macromolecules 2016 v.49 no.22 pp. 8593-8604
ISSN:
1520-5835
Subject:
alkenes; cracking; crosslinking; crystallization; energy; extensibility; hydrogen bonding; mechanical properties
Abstract:
... The development of advanced elastomers with a combination of high strength, large extensibility, and excellent flex-cracking resistance is a huge challenge. In this contribution, we proposed a novel strategy to engineer a multinetwork by incorporating weaker sacrificial hydrogen bonds and stronger Zn-based units into a chemically cross-linked cis-1,4-polyisoprene network. The dynamic nature allows ...
DOI:
10.1021/acs.macromol.6b01576

7. Brushes of Cycled Macromolecules: Structure and Lubricating Properties

Author:
Zhulina, Ekaterina B.; Leermakers, Frans A. M.; Borisov, Oleg V.
Source:
Macromolecules 2016 v.49 no.22 pp. 8758-8767
ISSN:
1520-5835
Subject:
analytical methods; lubricants; models; polymers; prediction
Abstract:
... We present a theory describing structural properties of brushes formed by cycled macromolecules tethered to planar surface. Diverse architectures of macromolecules that differ with respect to position and number of subchains in macrocycle are considered. We use the self-consistent field analytical approach based on strong stretching approximation and assumption of Gaussian elasticity of brush-form ...
DOI:
10.1021/acs.macromol.6b01275

8. Can Hyperbranched Polymers Entangle? Effect of Hydrogen Bonding on Entanglement Transition and Thermorheological Properties of Hyperbranched Polyglycerol Melts

Author:
Schubert, Christian; Osterwinter, Carina; Tonhauser, Christoph; Schömer, Martina; Wilms, Daniel; Frey, Holger; Friedrich, Christian
Source:
Macromolecules 2016 v.49 no.22 pp. 8722-8737
ISSN:
1520-5835
Subject:
hydrogen bonding; melting; molecular weight; polymers; rheology; stickiness; topology; viscoelasticity; viscosity
Abstract:
... Melt rheology and thermal phase transition of a series of hyperbranched polyglycerol samples (hbPG) (DB ≈ 60%) in a broad molecular weight range (Mₙ = 600–440 000 g/mol) were investigated and correlated to both molecular weight and nature of the end group (hydroxyl vs permethylated and trimethylsilylated). The well-characterized and defined flexible polyethers are particularly suitable to shed lig ...
DOI:
10.1021/acs.macromol.6b00674

9. Comparison of Critical Adsorption Points of Ring Polymers with Linear Polymers

Author:
Ziebarth, Jesse D.; Gardiner, Abigail Anne; Wang, Yongmei; Jeong, Youncheol; Ahn, Junyoung; Jin, Ye; Chang, Taihyun
Source:
Macromolecules 2016 v.49 no.22 pp. 8780-8788
ISSN:
1520-5835
Subject:
Monte Carlo method; adsorption; computer simulation; liquid chromatography; molecular weight; polystyrenes; silica; temperature
Abstract:
... The critical adsorption points (CAP) for ring and linear polymers are determined and compared using Monte Carlo simulations and liquid chromatography experiments. The CAP is defined as the coelution point of ring or linear polymers with different molecular weights (MW). Computational studies show that the temperature at the CAP, TCAP, for rings is higher than TCAP for linear polymers regardless of ...
DOI:
10.1021/acs.macromol.6b01925

10. Complexation in Weakly Attractive Copolymers with Varying Composition and Topology: Linking Fluorescence Experiments and Molecular Monte Carlo Simulations

Author:
Hebbeker, Pascal; Steinschulte, Alexander A.; Schneider, Sabine; Okuda, Jun; Möller, Martin; Plamper, Felix A.; Schneider, Stefanie
Source:
Macromolecules 2016 v.49 no.22 pp. 8748-8757
ISSN:
1520-5835
Subject:
Monte Carlo method; composite polymers; fluorescence; fluorescence emission spectroscopy; fluorescent dyes; models; propylene oxide; topology
Abstract:
... The intramolecular complex formation occurring in miktoarm star polymers and block copolymers is investigated experimentally and by means of Monte Carlo simulations. The driving force of the complex formation is an attractive interaction between the different blocks. In the simulations, a simple bead–spring model with an attractive Lennard-Jones potential is used to mimic the complexation. The eff ...
DOI:
10.1021/acs.macromol.6b01786

11. Conditions Leading to Polyelectrolyte Complex Overcharging in Solution: Complexation of Poly(acrylate) Anion with Poly(allylammonium) Cation

Author:
Kremer, Tomislav; Kovačević, Davor; Salopek, Jasmina; Požar, Josip
Source:
Macromolecules 2016 v.49 no.22 pp. 8672-8685
ISSN:
1520-5835
Subject:
calorimetry; cations; flocculation; neutralization; pH; polymers
Abstract:
... Complexation between poly(acrylate) (PA) and poly(allylammonium) (PAH) macroions at pH = 7.0 was studied by means of electrokinetics, microcalorimetry, and DLS. At low polyelectrolyte concentrations and no electrolyte present strong overcharging of primary nanocomplexes occurred. In contrast, the increase in polyelectrolyte concentration led to flocculation taking place near the equivalence. The n ...
DOI:
10.1021/acs.macromol.6b01892

12. Criticality and Connectivity in Macromolecular Charge Complexation

Author:
Qin, Jian; de Pablo, Juan J.
Source:
Macromolecules 2016 v.49 no.22 pp. 8789-8800
ISSN:
1520-5835
Subject:
Gibbs free energy; dendrimers; electrolytes; fractal dimensions; osmotic pressure; physical phases
Abstract:
... We examine the role of molecular connectivity and architecture on the complexation of ionic macromolecules (polyelectrolytes) of finite size. A unified framework is developed and applied to evaluate the electrostatic correlation free energy for point-like, rod-like, and coil-like molecules. That framework is generalized to molecules of variable fractal dimensions, including dendrimers. Analytical ...
DOI:
10.1021/acs.macromol.6b02113

13. Cyclopolymerization of Bis(diazocarbonyl) Compounds Leading to Well-Defined Polymers Essentially Consisting of Cyclic Constitutional Units

Author:
Shimomoto, Hiroaki; Kikuchi, Misaki; Aoyama, Junya; Sakayoshi, Dai; Itoh, Tomomichi; Ihara, Eiji
Source:
Macromolecules 2016 v.49 no.22 pp. 8459-8465
ISSN:
1520-5835
Subject:
glass transition temperature; matrix-assisted laser desorption-ionization mass spectrometry; polymers
Abstract:
... Cyclopolymerization of bis(diazocarbonyl) compounds is described for the first time. By choosing appropriate reaction conditions and monomer structures, the cyclopolymerization of bis(diazoacetate)s efficiently proceeded to give carbon–carbon main chain cyclopolymers with well-defined structures, as confirmed by MALDI-TOF-MS analyses. The products are a new kind of cyclopolymer with respect to pol ...
DOI:
10.1021/acs.macromol.6b01809

14. Dynamics of a Paradigmatic Linear Polymer: A Proton Field-Cycling NMR Relaxometry Study on Poly(ethylene–propylene)

Author:
Hofmann, M.; Kresse, B.; Heymann, L.; Privalov, A. F.; Willner, L.; Fatkullin, N.; Aksel, N.; Fujara, F.; Rössler, E. A.
Source:
Macromolecules 2016 v.49 no.22 pp. 8622-8632
ISSN:
1520-5835
Subject:
isotope dilution technique; melting; models; molecular weight; nuclear magnetic resonance spectroscopy; polymers; temperature; variance
Abstract:
... The dynamics of melts of linear poly(ethylene-alt-propylene) (PEP) of different molar masses (M) is investigated by ¹H field-cycling (FC) NMR relaxometry. Employing a commercial and a home-built relaxometer the spin-lattice relaxation rate R₁(ω) is measured in the frequency range of 200 Hz to 30 MHz and the temperature range of 200–400 K. Transforming the FC NMR relaxation data to the susceptibili ...
DOI:
10.1021/acs.macromol.6b01906

15. Electrostatic Self-Assembly of Dendrimer Macroions and Multivalent Dye Counterions: The Role of Solution Ionic Strength

Author:
Mariani, Giacomo; Schweins, Ralf; Gröhn, Franziska
Source:
Macromolecules 2016 v.49 no.22 pp. 8661-8671
ISSN:
1520-5835
Subject:
dendrimers; dyes; electrolytes; electrostatic interactions; ionic strength; models; nanoparticles
Abstract:
... The fundamental understanding of the driving forces in electrostatic self-assembly is highly desirable for the design of novel systems and of more effective synthesis strategies. The focus of this study is the effects of the electrostatic interaction on supramolecular self-assembled nanoparticles formed by cationic dendrimers as model polyelectrolytes and oppositely charged di- and trivalent dyes, ...
DOI:
10.1021/acs.macromol.6b00565

16. Epoxy Resin Thermosets Derived from Trehalose and β-Cyclodextrin

Author:
Zhang, Quanxuan; Molenda, Monika; Reineke, Theresa M.
Source:
Macromolecules 2016 v.49 no.22 pp. 8397-8406
ISSN:
1520-5835
Subject:
adhesion; anhydrides; beta-cyclodextrin; biodegradability; biological resistance; carboxylic acids; crosslinking; epoxides; feedstocks; glass transition temperature; hydrolysis; modulus of elasticity; moieties; polymers; resins; shrinkage; strength (mechanics); thermal stability; trehalose; water solubility
Abstract:
... Epoxy resins are ubiquitous in high-performance composite applications because of their excellent mechanical strength, thermal and chemical resistance, strong adhesion, and low shrinkage after curing. Bio-based epoxy resins derived from natural products such as carbohydrates offer tremendous potential for creating new polymeric materials. Sugars and their derivatives often offer great biodegradabi ...
DOI:
10.1021/acs.macromol.6b01861

17. Free Radical Propagation Rate Coefficients of N-Containing Methacrylates: Are We Family?

Author:
Kockler, Katrin B.; Fleischhaker, Friederike; Barner-Kowollik, Christopher
Source:
Macromolecules 2016 v.49 no.22 pp. 8572-8580
ISSN:
1520-5835
Subject:
esters; free radicals; gel chromatography; polymethylmethacrylate
Abstract:
... Nitrogen-containing methacrylates are a highly interesting class of monomers, yet only very limited data exist describing their propagation rate coefficients, kₚ. Herein, we investigate the propagation behavior of three N-containing monomers, namely 2-(N,N-diethylamino)ethyl methacrylate (DEAEMA), 2-(N,N-dimethylamino)ethyl methacrylate (DMAEMA), and 3-(N,N-dimethylamino)propyl methacrylate (DMAPM ...
DOI:
10.1021/acs.macromol.6b01957

18. Generation of Fluorescent and Stable Conjugated Polymer Nanoparticles with Hydrophobically Modified Poly(acrylate)s

Author:
Yan, Liang; Cui, Xiaolin; Harada, Takaaki; Lincoln, Stephen F.; Dai, Sheng; Kee, Tak W.
Source:
Macromolecules 2016 v.49 no.22 pp. 8530-8539
ISSN:
1520-5835
Subject:
adverse effects; fluorescence; fluorescent dyes; hydrophobicity; image analysis; ionic strength; moieties; nanoparticles; phosphates; photostability; polymers; spectroscopy; stabilizers; toxicity
Abstract:
... Conjugated polymer nanoparticles hold promise as fluorescence imaging agents because of their high brightness and photostability. However, their aggregation and precipitation at the high ionic strengths in physiological conditions present an impediment to their applications in biological imaging. In this study, hydrophobic linear alkyl group substituted poly(acrylate)s, PAACn, are synthesized and ...
DOI:
10.1021/acs.macromol.6b02002

19. High-Purity Semiconducting Single-Walled Carbon Nanotubes via Selective Dispersion in Solution Using Fully Conjugated Polytriarylamines

Author:
Wang, Po-I; Tsai, Chou-Yi; Hsiao, Yung-Jou; Jiang, Jyh-Chiang; Liaw, Der-Jang
Source:
Macromolecules 2016 v.49 no.22 pp. 8520-8529
ISSN:
1520-5835
Subject:
carbon monoxide; carbon nanotubes; energy; molecular models; optical isomerism; polymers; toluene
Abstract:
... A new approach for polytriarylamine (PTAA)-assisted selective dispersion for single-walled carbon nanotubes (SWNTs) in a toluene solution has been developed. The triarylamine-based conjugated polymers are able to selectively wrap the SWNTs with specific chiral indices depending on their backbone structures (e.g., PTAA₁₂, PTAA₁₂-P, and PTAA₁₂-BP) and side-chain functionality (e.g., PTAA₆, PTAA₆-alt ...
DOI:
10.1021/acs.macromol.6b01991

20. Hollow Polymeric Capsules from POSS-Based Block Copolymer for Photodynamic Therapy

Author:
Zhang, Zhenghe; Xue, Yudong; Zhang, Pengcheng; Müller, Axel H. E.; Zhang, Weian
Source:
Macromolecules 2016 v.49 no.22 pp. 8440-8448
ISSN:
1520-5835
Subject:
composite polymers; confocal laser scanning microscopy; copolymerization; coumarin; crosslinking; encapsulation; glutathione; hydrofluoric acid; micelles; pH; photochemotherapy; redox potential; scanning electron microscopy; toxicity; transmission electron microscopy
Abstract:
... A novel amphiphilic diblock copolymer, PHEMAPOSS-b-P(DMAEMA-co-CMA), was prepared via reversible addition–fragmentation chain transfer (RAFT) polymerization, where PHEMAPOSS block was first synthesized using a methacrylate monomer based on polyhedral oligomeric silsesquioxane (HEMAPOSS), and PHEMAPOSS was further utilized to prepare the block copolymer via RAFT copolymerization of 2-(dimethylamino ...
DOI:
10.1021/acs.macromol.6b02414