Molecular dynamics in semifluorinated‐side‐chain polysulfone studied by broadband dielectric spectroscopy

Tsuwi, Julius; Pospiech, Doris; Jehnichen, Dieter; Häußler, Liane; Kremer, Friedrich

doi:10.1002/app.26045

Cited by 10 publications

(21 citation statements)

References 48 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The relaxation is observed in crystalline as well as in liquid crystalline phase for the copolymer 31 mol%, while for the copolymer 68 mol% the relaxation can be resolved only in the crystalline phase. A relaxation in the same frequency/temperature range has been observed by dielectric spectroscopy in systems with a main-chain of polysulfones and sf side chains identical with those of the present work [20]. The relaxation was assigned there to a glass transition of the domains formed by sf side chains.…”

Section: β Sf Relaxationsupporting

confidence: 58%

“…The copolymers where the side chains are organized follow the additive rule, however the values in these samples are lower than those expected taking into account the value observed for the 11 of dielectric strength due to cancellation of dipole moments. A relaxation with similar characteristics has already been observed in systems having fluoroalkanes as side chains and has been ascribed to motions of CF 3 -groups [19,20,22,29].…”

Section: γ Sf Relaxationmentioning

confidence: 62%

“…Results of molecular dynamics have been reported for sf alkanes [15][16], as well as for various polymers with attached sf chains as side chains either as homopolymers [17][18][19][20] or as copolymers [21][22][23]. The molecular mobility of the chain backbone, as well as that of the sf side chains, ranging from local to segmental motions was followed and related to 28/[282] S. Kripotou et al the structure of the systems.…”

Section: Introductionmentioning

confidence: 97%

See 2 more Smart Citations

Semifluorinated Methacrylate Random Copolymers: Phase Transitions and Molecular Dynamics

Kripotou

Pandis

Kyritsis

et al. 2015

Molecular Crystals and Liquid Crystals

View full text Add to dashboard Cite

Random copolymers of methyl methacrylate (MMA) and sermifluorinated methacrylate (sfMA), with constant side chain length (H 10 F 10 ), as comonomers and various sfMA molar contents were studied by Dielectric Relaxation Spectroscopy (DRS) technique with respect to their phase transitions and molecular dynamics. DRS technique was proven a suitable technique for the detection of the phase transitions that take place in the systems under investigation, as it follows from the comparison with Differential Scanning Calorimetry (DSC) technique, which is traditionally used. Regarding molecular mobility, molecular motions of both the main chain and the sf side chains were followed, while different dynamics was recorded depending on the structure of the copolymers.

show abstract

Section: β Sf Relaxationsupporting

confidence: 58%

Section: γ Sf Relaxationmentioning

confidence: 62%

Section: Introductionmentioning

confidence: 97%

See 1 more Smart Citation

Semifluorinated Methacrylate Random Copolymers: Phase Transitions and Molecular Dynamics

Kripotou

Pandis

Kyritsis

et al. 2015

Molecular Crystals and Liquid Crystals

View full text Add to dashboard Cite

show abstract

“…1,4 The stability of fluorinated and semifluorinated polymers is a result of the packing of the fluorinated segments along the backbone. [5][6][7][8][9] Recent developments for semifluorinated carbon chains include the field of ophthalmology where they are finding uses in retinal unfolding and permanent retinal tamponade. 2 Diverse medical applications include their use as temporary blood substitutes and burn treatments 3,10-12 because they are biologically compatible and physiologically inert.…”

Section: Introductionmentioning

confidence: 99%

Interfacial properties of semifluorinated alkane diblock copolymers

Pierce

Tsige

Borodin

et al. 2008

The Journal of Chemical Physics

View full text Add to dashboard Cite

The liquid-vapor interfacial properties of semifluorinated linear alkane diblock copolymers of the form F(3)C(CF(2))(n-1)(CH(2))(m-1)CH(3) are studied by fully atomistic molecular dynamics simulations. The chemical composition and the conformation of the molecules at the interface are identified and correlated with the interfacial energies. A modified form of the Optimized Parameter for Liquid Simulation All-Atom (OPLS-AA) force field of Jorgensen and co-workers [J. Am. Chem. Soc. 106, 6638 (1984); 118, 11225 (1996); J. Phys. Chem. A 105, 4118 (2001)], which includes specific dihedral terms for H-F blocks-and corrections to the H-F nonbonded interaction, is used together with a new version of the exp-6 force field developed in this work. Both force fields yield good agreement with the available experimental liquid density and surface tension data as well as each other over significant temperature ranges and for a variety of chain lengths and compositions. The interfacial regions of semifluorinated alkanes are found to be rich in fluorinated groups compared to hydrogenated groups, an effect that decreases with increasing temperature but is independent of the fractional length of the fluorinated segments. The proliferation of fluorine at the surface substantially lowers the surface tension of the diblock copolymers, yielding values near those of perfluorinated alkanes and distinct from those of protonated alkanes of the same chain length. With decreasing temperatures within the liquid state, chains are found to preferentially align perpendicular to the interface, as previously seen.

show abstract

“…As a result of the strong interaction between the fluorinated segments, e.g. perfluoroalkyl groups, the side chains determine the structure behaviour strongly (Friedel et al, 2000;Gottwald et al, 2002) and influence physical parameters and application properties significantly (Gopalan et al, 2002;Appelhans et al, 2005;Tsuwi et al, 2007). In general, sufficiently long SF side chains are organized in ordered structures Busch et al, 2007).…”

Section: Introductionmentioning

confidence: 99%

Temperature dependant structural changes in thin films of random semifluorinated PMMA copolymers

et al. 2013

Self Cite

View full text Add to dashboard Cite

Semifluorinated (SF) side chain polymers show phase separation between polymer backbone and SF side chains. Due to strong interaction between SF segments the side chains determine the structure behaviour strongly, often resulting in layered structures in which backbones and layers of SF side chains alternate. The interest in this work was directed to find out the dependence of these structures on concentration of SF side chains. Thin films of random copolymers consisting of methylmethacrylate (MMA) and semifluorinated side chain methacrylate (SFMA) segments and with different fluorine content in the perfluoroalkyl side chains (abbreviated as H10F10 and H2F8) were prepared by spin-coating. Phase separation and structure changes were initiated by external subsequent annealing. Corresponding bulk material served as basic information. Generation of ordered structures and variation of film parameters were observed using different X-ray scattering methods (XRR, GIWAXS, and GISAXS). The phase behaviour in bulk is governed by the SF side chain amount and their specific fluorine content which control the self-organization tendency of SF side chains.Additionally, the confinement in thin films generates an orientation of side chains normally to film surface.

show abstract

Molecular dynamics in semifluorinated‐side‐chain polysulfone studied by broadband dielectric spectroscopy

Cited by 10 publications

References 48 publications

Semifluorinated Methacrylate Random Copolymers: Phase Transitions and Molecular Dynamics

Semifluorinated Methacrylate Random Copolymers: Phase Transitions and Molecular Dynamics

Interfacial properties of semifluorinated alkane diblock copolymers

Temperature dependant structural changes in thin films of random semifluorinated PMMA copolymers

Contact Info

Product

Resources

About