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  • 1. Alizadehheidari, Mohammadreza
    et al.
    Werner, Erik
    Noble, Charleston
    Reiter-Schad, Michaela
    Nyberg, Lena K.
    Fritzsche, Joachim
    Mehlig, Bernhard
    Tegenfeldt, Jonas O.
    Ambjornsson, Tobias
    Persson, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology.
    Westerlund, Fredrik
    Nanoconfined Circular and Linear DNA: Equilibrium Conformations and Unfolding Kinetics2015In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 48, no 3, p. 871-878Article in journal (Refereed)
    Abstract [en]

    Studies of circular DNA confined to nanofluidic channels are relevant both from a fundamental polymer-physics perspective and due to the importance of circular DNA molecules in vivo. We here observe the unfolding of confined DNA from the circular to linear configuration as a light-induced double-strand break occurs, characterize the dynamics, and compare the equilibrium conformational statistics of linear and circular configurations. This is important because it allows us to determine to what extent existing statistical theories describe the extension of confined circular DNA. We find that the ratio of the extensions of confined linear and circular DNA configurations increases as the buffer concentration decreases. The experimental results fall between theoretical predictions for the extended de Gennes regime at weaker confinement and the Odijk regime at stronger confinement. We show that it is possible to directly distinguish between circular and linear DNA molecules by measuring the emission intensity from the DNA. Finally, we determine the rate of unfolding and show that this rate is larger for more confined DNA, possibly reflecting the corresponding larger difference in entropy between the circular and linear configurations.

  • 2.
    Atthoff, Björn
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Nederberg, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Biodegradable Ionomers2006In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 39, no 11, p. 3907-3913Article in journal (Refereed)
    Abstract [en]

    Several telechelic anionic or cationic ionomers were synthesized starting from poly(trimethylene carbonate) diols (PTMC) of different molecular weight, ranging from 1000 to 12 000 g/mol. In the synthesis of the anionomer, addition of sulfur trioxide trimethylene complex to the PTMC end-group hydroxyls and subsequent ion exchange afforded a disulfate monoester sodium salt. The cationomer was synthesized in two steps. Acylation of the PTMC diol using 4-chlorobuturyl chloride was followed by displacement of the alkyl chloride with trimethylamine to give a quaternary ammonium salt. These ionomers showed excellent swelling properties, up to around 500% in H2O, while the unfunctionlized PTMC did not swell at all. The lowest molecular weight ionomers were soluble in both water and chloroform. The physical properties of the ionomers were analyzed with oscillating rheological experiments. Interestingly, the ionomers displayed "rubbery plateau". The mechanical and swelling properties may be linked to phase separation resulting in ionic aggregates within the bulk, which may function as physical cross-links. At ambient temperatures, the PTMC starting material behaved like a highly viscous fluid, while the ionomers behaved as elastomers. In a hydrophilic environment, the ionomers displayed a surface rearrangement making the surface of the ionomer hydrophilic by allowing the ionic end groups to appear at the water ionomer interface. In air or vacuum all the ionic groups were found in the bulk of the material as analyzed by XPS or contact angle measurements. Finally, we showed that with the specific ionic groups it was possible to complex specific molecules to the ionomers.

  • 3.
    Ebadi, Mahsa
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Eriksson, Therese
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Mandal, Prithwiraj
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Costa, Luciano T.
    Univ Fed Fluminense, Inst Quim, Dept Fis Quim, BR-24020150 Niteroi, RJ, Brazil.
    Araujo, Carlos Moyses
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Theory.
    Mindemark, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Restricted Ion Transport by Plasticizing Side Chains in Polycarbonate-Based Solid Electrolytes2020In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 53, no 3, p. 764-774Article in journal (Refereed)
    Abstract [en]

    Increasing the ionic conductivity has for decades been an overriding goal in the development of solid polymer electrolytes. According to fundamental theories on ion transport mechanisms in polymers, the ionic conductivity is strongly correlated to free volume and segmental mobility of the polymer for the conventional transport processes. Therefore, incorporating plasticizing side chains onto the main chain of the polymer host often appears as a clear-cut strategy to improve the ionic conductivity of the system through lowering of the glass transition temperature (T-g) This intended correlation between Tg and ionic conductivity is, however, not consistently observed in practice. The aim of this study is therefore to elucidate this interplay between segmental mobility and polymer structure in polymer electrolyte systems comprising plasticizing side chains. To this end, we utilize the synthetic versatility of the ion-conductive poly(trimethylene carbonate) (PTMC) platform. Two types of host polymers with side chains added to a PTMC backbone are employed, and the resulting electrolytes are investigated together with the side chain-free analogue both by experiment and with molecular dynamics (MD) simulations. The results show that while added side chains do indeed lead to a lower Tg, the total ionic conductivity is highest in the host matrix without side chains. It was seen in the MD simulations that while side chains promote ionic mobility associated with the polymer chain, the more efficient interchain hopping transport mechanism occurs with a higher probability in the system without side chains. This is connected to a significantly higher solvation site diversity for the Li+ ions in the side-chain-free system, providing better conduction paths. These results strongly indicate that the side chains in fact restrict the mobility of the Li+ ions in the polymer hosts.

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  • 4.
    Eriksson, Therese
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Gudla, Harish
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Manabe, Yumehiro
    Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8 Kita-ku, Sapporo, Hokkaido060-8628, Japan.
    Yoneda, Tomoki
    Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8 Kita-ku, Sapporo, Hokkaido060-8628, Japan.
    Friesen, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Zhang, Chao
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Inokuma, Yasuhide
    Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8 Kita-ku, Sapporo, Hokkaido060-8628, Japan.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Mindemark, Jonas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Carbonyl-Containing Solid Polymer Electrolyte Host Materials: Conduction and Coordination in Polyketone, Polyester, and Polycarbonate Systems2022In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 55, no 24, p. 10940-10949Article in journal (Refereed)
    Abstract [en]

    Research on solid polymer electrolytes (SPEs) is now moving beyond the realm of polyethers that have dominated the field for several decades. A promising alternative group of candidates for SPE host materials is carbonyl-containing polymers. In this work, SPE properties of three different types of carbonyl-coordinating polymers are compared: polycarbonates, polyesters, and polyketones. The investigated polymers were chosen to be as structurally similar as possible, with only the functional group being different, thereby giving direct insights into the role of the noncoordinating main-chain oxygens. As revealed by experimental measurements as well as molecular dynamics simulations, the polyketone possesses the lowest glass transition temperature, but the ion transport is limited by a high degree of crystallinity. The polycarbonate, on the other hand, displays a relatively low coordination strength but is instead limited by its low molecular flexibility. The polyester performs generally as an intermediate between the other two, which is reasonable when considering its structural relation to the alternatives. This work demonstrates that local changes in the coordinating environment of carbonyl-containing polymers can have a large effect on the overall ion conduction, thereby also showing that desired transport properties can be achieved by fine-tuning the polymer chemistry of carbonyl-containing systems.

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  • 5.
    Gogoll, Adolf
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Biochemistry and Organic Chemistry, Organic Chemistry I.
    Tegenfeldt, Jörgen
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Inorganic Chemistry.
    Oscarsson, Sven
    UNIV UPPSALA, CTR BIOMED, INST BIOCHEM, S-75123 UPPSALA, SWEDEN .
    CP/MAS carbon-13 NMR spectroscopy of epoxypropyl-activated agarose functionalized with pyridine derivatives1991In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 24, no 16, p. 4727-4728Article in journal (Refereed)
  • 6. Golker, Kerstin
    et al.
    Karlsson, Bjorn C. G.
    Olsson, Gustaf D.
    Rosengren, Annika M.
    Nicholls, Ian A.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC.
    Influence of Composition and Morphology on Template Recognition in Molecularly Imprinted Polymers2013In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 46, no 4, p. 1408-1414Article in journal (Refereed)
    Abstract [en]

    A combination of theoretical and experimental studies has provided correlations between molecularly imprinted polymer composition, morphology, and recognition behavior obtained using a series of bupivacaine-imprinted methacrylic acid (MAA)-ethylene glycol dimethacrylate copolymers differing in molar ratios of the respective monomers. Results extracted from analysis of molecular dynamics (MD) trajectory data demonstrated that stability and frequency of interactions between bupivacaine and the monomers in the prepolymerization phase were strongly affected by minor changes in polymer composition, which in turn affected binding site affinity and heterogeneity of the imprinted polymers. Moreover, through the characterization of polymer morphology, we show that higher molar fractions of MAA resulted in polymeric materials with increased pore size, a feature that enhanced the binding capacity of the polymers. Furthermore, the results presented point at the strength of MD for predicting MIP-template binding capacity and affinity.

  • 7. Kamata, Yohei
    et al.
    Parnell, Andrew J.
    Gutfreund, Philipp
    Skoda, Maximilian W. A.
    Dennison, Andrew J. C.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy.
    Barker, Robert
    Mai, Shaomin
    Howse, Jonathan R.
    Ryan, Anthony J.
    Torikai, Naoya
    Kawaguchi, Masami
    Jones, Richard A. L.
    Hydration and Ordering of Lamellar Block Copolymer Films under Controlled Water Vapor2014In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 47, no 24, p. 8682-8690Article in journal (Refereed)
    Abstract [en]

    Amphiphilic block copolymers within a range of volume fraction spontaneously form vesicles in aqueous solution, where a water core is enclosed by a polymer bilayer. Thin-film rehydration is a method used to produce vesicles routinely; a thin film is immersed in water, the film swells, and vesicles are formed which bleb off from the film surface. We have studied the early stages of hydration for PEOPBO block copolymer thin films under controlled water vapor conditions to understand this formation mechanism and so enable more efficient ways to encapsulate molecules using this method. Neutron and X-ray measurements show that the initial film exhibits weakly ordered structure with isotropic parallel and vertical orientation; the films initially swell and maintain the same orientation. At a critical point the layer swells rapidly and makes highly ordered lamellae structure at the same time. The lamellae are almost exclusively oriented parallel to the substrate and swell with increasing water absorption.

  • 8.
    Kamerlin, Natasha
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics, Algebra and Geometry.
    Elvingson, Christer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Collapse Dynamics of Core-Shell Nanogels2016In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 49, no 15, p. 5740-5749Article in journal (Refereed)
    Abstract [en]

    Stimuli-responsive core shell nanogels display collapse properties which are determined by both the core and the shell. We examine the equilibrium properties and the detailed structural changes during a collapse transition of polymer core shell nanoparticles using Brownian dynamics simulations. Gel particles with randomly distributed cross-linking nodes are created. The influence of the cross-linking degree, core/shell mass ratio, and the strength of the interparticle attractive interaction on the collapse behavior is investigated. Both collapsed core and collapsed shell structures are considered and compared with collapsed homopolymer networks. The transition time was found to be reduced with increasing cross-linking degree and inversely related to the depth of the Lennard-Jones potential. Similar to the kinetics of single chain collapse, there is an initial formation of clusters, in this case near cross-linking nodes, and a subsequent coarsening to form a compact globule. Where the nanogels were collapsed into a compact core, the deformation was found to be essentially symmetric, with a significantly slower relaxation time for the shell units compared to the core collapse transition time. Reducing the core size, the shell units were less affected by the presence of a collapsing core. For the system with a collapsing shell, our simulations reveal in some cases an inversion, with the shell compressing and eventually squeezing out the core units. This effect was more pronounced with decreasing cross-linking degree and core/shell mass ratio.

  • 9.
    Kamerlin, Natasha
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics.
    Elvingson, Christer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Deformation Behavior and Failure of Bimodal Networks2017In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 50, no 19, p. 7628-7635Article in journal (Refereed)
    Abstract [en]

    Using computer simulations, we have investigated the deformation and stress-strain behavior of a series of ideal gels without any defects, with a bimodal molecular weight distribution, subject to tensile strains. These networks were prepared with a spatially homogeneous distribution of short and long chains, where all chains are elastically active, without needing to consider possible effects of chain aggregation or entanglements on the physical properties. For all fractions of short chains, the first chains to rupture were the short chains that were initially oriented along the strain axis. The average orientation of the short chains slightly increased with decreasing fraction of short chains. This could be explained by the detailed structure of the network at different compositions. Analysis of the stress-strain relation for the short and long chains showed that the stress was not uniformly shared. Instead, the short chains are more strongly deformed whereas the long chains only make a negligible contribution at smaller strains. The mechanical properties of the bimodal networks at lower fractions of short chains also deviated from the behavior of equivalent unimodal networks with the corresponding average chain length, showing that bimodality alone is sufficient to increase both the maximum extensibility and toughness.

  • 10.
    Kamerlin, Natasha
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics, Algebra and Geometry.
    Elvingson, Christer
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Deformation Behavior of Homogeneous and Heterogeneous Bimodal Networks2017In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 50, no 23, p. 9353-9359Article in journal (Refereed)
    Abstract [en]

    In this study, the effect of spatial heterogeneities on the deformation behavior during uniaxial elongation as well as the ultimate properties of bimodal gels consisting of both short and long chains was investigated by molecular simulations. Defect-free networks were created containing dense short-chain clusters and compared with gels having a homogeneous distribution of chains. In both cases, the first chains to rupture were the ones already aligned along the strain axis prior to imposing a strain. The presence of clusters was generally not found to improve the ultimate stress or toughness; the short chains within the clusters were effectively shielded from deformation, even at large fractions of short chains. The heterogeneous network tended to be weaker than the corresponding homogeneous network at a given fraction of short chains, fracturing before any significant deformation of clusters had taken place. The deformation behavior was, however, found to be sensitive to the degree of heterogeneity and the number of intercluster connections. At large fractions of short chains, clustering offered an improvement in the ultimate strain compared to a homogeneous bimodal network and also an equivalent unimodal network with the corresponding number-average chain length, thus providing a small improvement in toughness.

  • 11.
    Korolkovas, Airidas
    et al.
    Inst Laue Langevin, 71 Rue Martyrs, F-38000 Grenoble, France.;Univ Grenoble Alpes, Liphy, 140 Rue Phys, F-38402 St Martin Dheres, France..
    Rodriguez-Emmenegger, Cesar
    Rhein Westfal TH Aachen, DWI Leibniz Inst Interact Mat, Forckenbeckstr 50, D-52074 Aachen, Germany.;Rhein Westfal TH Aachen, Inst Tech & Macromol Chem, Forckenbeckstr 50, D-52074 Aachen, Germany.;Univ Sheffield, Dept Phys & Astron, Sheffield S10 2TN, S Yorkshire, England..
    Pereira, Andres de los Santos
    Acad Sci Czech Republic, Inst Macromol Chem, Vvi, Heyrovsky Sq 2, CR-16206 Prague, Czech Republic..
    Chenneviere, Alexis
    Univ Paris Saclay, CNRS, CEA, Lab Leon Brillouin, F-91191 Gif Sur Yvette, France..
    Restagno, Frederic
    Univ Paris Saclay, Univ Paris Sud, CNRS, Phys Solides Lab, F-91405 Orsay, France..
    Wolff, Maximilian
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics.
    Adlmann, Franz
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Materials Physics.
    Dennison, Andrew J. C.
    Inst Laue Langevin, 71 Rue Martyrs, F-38000 Grenoble, France.;Tech Univ Berlin, Dept Chem, D-10623 Berlin, Germany..
    Gutfreund, Philipp
    Inst Laue Langevin, 71 Rue Martyrs, F-38000 Grenoble, France..
    Polymer Brush Collapse under Shear Flow2017In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 50, no 3, p. 1215-1224Article in journal (Refereed)
    Abstract [en]

    Shear responsive surfaces offer potential advances in a number of applications. Surface functionalization using polymer brushes is one route to such properties, particularly in the case of entangled polymers. We report on neutron reflectometry measurements of polymer brushes in entangled polymer solutions performed under controlled shear as well as coarse-grained computer simulations corresponding to these interfaces. Here we show a reversible and reproducible collapse of the brushes, increasing with the shear rate. Using two brushes of greatly different chain lengths and grafting densities, we demonstrate that the dynamics responsible for the structural change of the brush are governed by the free chains in solution rather than the brush itself, within the range of parameters examined. The phenomenon of the brush collapse could find applications in the tailoring of nanosensors and as a way to dynamically control surface friction and adhesion.

  • 12.
    Liu, Chun-Yan
    et al.
    Sichuan Univ, Coll Polymer Sci & Engn, State Key Lab Polymer Mat Engn, Chengdu 610065, Peoples R China..
    Li, De -Long
    Sichuan Univ, Coll Polymer Sci & Engn, State Key Lab Polymer Mat Engn, Chengdu 610065, Peoples R China..
    Wang, Zhi-Hao
    Sichuan Univ, Coll Polymer Sci & Engn, State Key Lab Polymer Mat Engn, Chengdu 610065, Peoples R China..
    Li, Yue
    Sichuan Univ, Coll Polymer Sci & Engn, State Key Lab Polymer Mat Engn, Chengdu 610065, Peoples R China..
    Zhou, Sheng-Yang
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Nanotechnology and Functional Materials.
    Xu, Ling
    Sichuan Univ, Sch Aeronaut & Astronaut, Chengdu 610065, Peoples R China..
    Zhong, Gan-Ji
    Sichuan Univ, Coll Polymer Sci & Engn, State Key Lab Polymer Mat Engn, Chengdu 610065, Peoples R China..
    Huang, Hua-Dong
    Sichuan Univ, Coll Polymer Sci & Engn, State Key Lab Polymer Mat Engn, Chengdu 610065, Peoples R China..
    Li, Zhong-Ming
    Sichuan Univ, Coll Polymer Sci & Engn, State Key Lab Polymer Mat Engn, Chengdu 610065, Peoples R China..
    Massively Parallel Aligned Poly(vinylidene fluoride) Nanofibrils in All-Organic Dielectric Polymer Composite Films for Electric Energy Storage2023In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 56, no 4, p. 1481-1491Article in journal (Refereed)
    Abstract [en]

    It is a formidable challenge to combine the perform-ance advantages of linear and nonlinear polymer dielectrics for developing all-organic film capacitors with high energy density and low loss. In this work, massively parallel aligned poly(vinylidene fluoride) (PVDF) nanofibrils were in situ fabricated for the first time in the polyethylene (PE) matrix via a multistage stretching technology involving hot stretching and solid-state stretching at an elevated temperature. The largely enhanced interfacial area of PVDF nanofibrils could effectively induce interfacial polarization, imparting PE composite films with a high dielectric constant of 4.50. More interestingly, the nanoconfinement effect of PVDF nanofibrils greatly restricted the migration of free electrons and impurity ions, and an impressive breakdown strength of 624 MV m-1 was obtained. As a result, the as-prepared PE/PVDF composite films exhibited an attractive discharged energy density of as high as 6.4 J cm-3, which was more than 10 times of the conventional counterparts, and outperformed the current linear dielectric polymers. The ingenious structure design of in situ nonlinear dielectric nanofibrils provides a promising approach to maximize the advantageous polarizations and minimize the disadvantageous polarizations in the linear and nonlinear polymer dielectric blends, achieving all-organic polymer dielectric composite films with high energy density and low loss.

  • 13.
    Mahlin, Denny
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Ridell, Annika
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Frenning, Göran
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Pharmacy, Department of Pharmacy.
    Engström, Sven
    Solid-state characterisation of PEG 4000/monoolein mixtures2004In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 37, no 7, p. 2665-2667Article in journal (Refereed)
  • 14.
    Mindemark, Jonas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    End-Group-Catalyzed Ring-Opening Polymerization of Trimethylene Carbonate2007In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 40, no 10, p. 3515-3517Article in journal (Refereed)
    Abstract [en]

    A controlled self-catalyzed polymerization reaction yielding well-defined heterotelechelic polymer chains and eliminating low molecular weight catalyst residues in the final polymer product were analyzed by utilizing a ternary amine. The molecular weights were kept relatively low for end-group analysis by Nuclear Magnetic Resonance spectroscopy (NMR) and linear correlation between the degree of polarization and monomer were found. NMR results show that the polydispersities remained low at high monomer conversions and longer reaction times after full conversion led to a larger molecular weight distribution. The results also show that the ternary amine catalyst are attached to the growing polymer chains that is shown by a downfield shift from 2.44 to 2.56 ppm. The benzoic acid ester of the ternary amine is found to be potent catalyst of Ring-Opening Polymerization (ROP).

  • 15.
    Nilsson, Kristian
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Mellin, Lisa
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Nederberg, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Bowden, Tim
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Addition of Thiol-Containing Ligands to a Surface-Active Michael Acceptor2007In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 40, no 4, p. 901-908Article in journal (Refereed)
    Abstract [en]

    This paper introduces the synthesis, characterization, surface properties, and reactions of maleic acid monoester end group functionalized polymers. Acylation using maleic acid anhydride of hydroxyl end groups present in either poly(ethylene glycol) (PEG) or poly(trimethylene carbonate) (PTMC) afforded the corresponding maleic acid monoester salts (PEGDM) or (PTMCM). Michael additions of ethanethiol or cysteine to the conjugated double bonds were performed in solution or at a polymer film−water interface. To further evaluate the reactivity and regioselectivity of the thiol addition to maleic acid monoester, a model compound, benzyl 6-hydroxyhexanoate, was used to aid a spectroscopic characterization. Film properties, evaluated with contact angle measurements, of PTMCM revealed surface-active properties of ionic maleic acid monoester salt. Further contact angle measurements showed that maleic acid monoesters present at the polymer−water interface could be reacted with the mercapto group in cysteine to give an amino acid decorated surface.

  • 16.
    Ossipov, Dmitri A.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Piskounova, Sonya
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Materials Chemistry, Polymer Chemistry.
    Poly(vinyl alcohol) cross-linkers for in vivo injectable hydrogels2008In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 41, no 11, p. 3971-3982Article in journal (Refereed)
    Abstract [en]

    New poly(vinyl alcohol) (PVA) derivatives containing different pendant chemoselective functionalities have been prepared for the in situ formation of hydrogels at physiological conditions. Particularly, incorporations of thiol, cysteine 1,2-aminothiol, and aminooxy side chains to PVA were performed for the first time by direct coupling of the protected nucleophilic functionalities to PVA's hydroxyl groups via carbamate linkages followed by acidic deprotection. In the second approach, PVA was first derivatized to a low degree (3%) with amino groups which were used to quantitatively react with different N-hydroxysuccinimide esters of carboxylic acids containing maleimide, a-iodoacetyl, or acrylate thiophilic functionalities. The utility of the amino-derivatized PVA was also demonstrated for further functionalization with semicarbazide terminated side chains. The ability of the new PVA derivatives to act as multifunctional cross-linking agents was examined in the course of in situ cross-linking reactions with hyaluronic acid carrying aldehyde groups. Use of multi functional PVA cross-linkers was shown to give short gelation times, i.e., within half a minute, which is critical for clinical applications. The hyaluronan hydrogels were enzymatically degradable as evidenced by the results of in vitro degradation by hyaluronidase. Moreover, these hydrogels were found to be nontoxic to human dermal fibroblasts. Hence, PVA-based multifunctional cross-linkers can extend the scope of in situ preparation and properties of hydrogel-based synthetic mimics of extracellular matrix as compared with well established bifunctional poly(ethylene glycol) analogs.

  • 17.
    Ossipov, Dmitri
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Kootala, Sujit
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Yi, Zheyi
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Yang, Xia
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Hilborn, Jöns
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Polymer Chemistry.
    Orthogonal Chemoselective Assembly of Hyaluronic Acid Networks and Nanogels for Drug Delivery2013In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 46, no 10, p. 4105-4113Article in journal (Refereed)
    Abstract [en]

    Functionalization of hyaluronic acid (HA) with orthogonally reactive aldehyde and thiol groups permitted simultaneous bioconjugation and networking/nanostructuring of the HA chains for potential use as local and systemic delivery vehicles for medical therapies. In one experiment, the thiol-disulfide exchange reaction and carbazone chemistry were employed to construct a disulfide hydrogel matrix of HA macromolecules with the carbazone-linked poly(vinyl alcohol) prodrug of doxorubicin (PVA-DOX). In another experiment, orthogonal chemoselective reactions were utilized to prepare nanogel particles through conjugation of the polymeric PVA-DOX prodrug to HA and simultaneous attachment of hydrophobic fluorescent groups to the HA chains. The effect of the prodrug nanostructuring and functionalization with HA on the in vitro drug release and uptake by cancer cells was preliminary verified.

  • 18. Rangelov, Stanislav
    et al.
    Halacheva, Silvia
    Garamus, Vasil L
    Almgren, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Physical and Analytical Chemistry, Physical Chemistry.
    Structural Polymorphism Exhibited by Polyglycidol-Based Analogues to Pluronic Copolymers in Aqueous Solution2008In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 41, no 22, p. 8885-8894Article in journal (Refereed)
    Abstract [en]

    In this paper, nanostructures formed in water by a novel series of (G)n(PO)68(G)n triblock copolymers, where n = 18−135, and G and PO stand for glycidol and propylene oxide, respectively, are parametrized. The copolymers are considered analogues of Pluronic copolymers in which the flanking poly(ethylene oxide) (PEO) blocks are substituted by polyglycidol (PG). PG is structurally similar to PEO and differs in that each monomer unit bears a hydroxymethylene group. In composition, the copolymers are closest to the Pluronic series L121−F127. Dilute (but invariably above the critical aggregation concentration) aqueous solutions in the temperature interval 25−70 °C were investigated by means of dynamic and static light scattering, cryogenic transmission electron microscopy, and small-angle neutron scattering (SANS). In the temperature-composition continuum studied the novel copolymers exhibit rich structural polymorphism. Large compound particles as those observed earlier for related copolymers, small core-corona micelles, rods, and vesicles were detected and parametrized by combining light scattering and SANS. Upon heating, the simultaneous increase in both hydrophobicity of poly(propylene oxide) and hydrophilicity of PG cause counteracting effects that are reflected in appearance of maxima in the temperature dependence of aggregation numbers of the particles, variations in the density of the latter, and anomalous thermotropic transitions for some of the copolymers.

1 - 18 of 18
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