Targeted β-Phase Formation in Poly(fluorene)-Ureasil Grafted Organic-Inorganic Hybrids

© 2017 American Chemical Society. The development of synthetic strategies to control the molecular organization (and inherently linked optoelectronic properties) of conjugated polymers is critical for the development of efficient light-emitting devices. Here, we report a facile route using sol-gel chemistry to promote the formation of the β-phase through the covalent-grafting of poly[(9,9-dioctylfluorene)-co-(9,9-bis(8-hydroxyoctyl)fluorene)] (PFO-OH) to poly(oxyalkylene)/siloxane hybrids known as ureasils, due to the urea linkages binding the organic and inorganic components. Although grafting occurs within the siliceous domains, the degree of branching of the organic backbone determines the packing of the PFO-OH chains within the ureasil framework. Moreover, photoluminescence studies indicate that physical confinement also plays a key role in promoting the evolution of the β-phase of PFO-OH as the sol-gel transition proceeds. Spectroscopic and structural analyses reveal that dibranched ureasils promote linear packing of the PFO-OH chains, while tribranched ureasils exhibit a more open, distorted structure that restricts the packing efficacy and reduces the number of covalent anchorages. These results indicate that the organic-inorganic hybrid structure induces distinct levels of β-phase formation and that covalent grafting is a versatile approach to design novel poly(fluorene) hybrid materials with tailored optical properties

Targeted design leads to tunable photoluminescence from perylene dicarboxdiimide-poly(oxyalkylene)/siloxane hybrids for luminescent solar concentrators

The chain length and branching of the organic backbone of poly(oxyalkylene)/siloxane ureasils can be used to control the placement and orientation of a covalently-grafted perylene, leading to tunable photoluminescence.</p

Ureasil organic-inorganic hybrids as photoactive waveguides for conjugated polyelectrolyte luminescent solar concentrators

We test the potential of resonance energy transfer to enhance the performance of conjugated copolyelectrolyte donor–acceptor luminescent solar concentrators immobilised within a photoactive organic–inorganic ureasil waveguide.</p

The spectrum of Apert syndrome: phenotype, particularities in orthodontic treatment, and characteristics of orthognathic surgery

In the PubMed accessible literature, information on the characteristics of interdisciplinary orthodontic and surgical treatment of patients with Apert syndrome is rare. The aim of the present article is threefold: (1) to show the spectrum of the phenotype, in order (2) to elucidate the scope of hindrances to orthodontic treatment, and (3) to demonstrate the problems of surgery and interdisciplinary approach. Children and adolescents who were born in 1985 or later, who were diagnosed with Apert syndrome, and who sought consultation or treatment at the Departments of Orthodontics or Craniomaxillofacial Surgery at the Dental School of the University Hospital of Münster (n = 22; 9 male, 13 female) were screened. Exemplarily, three of these patients (2 male, 1 female), seeking interdisciplinary (both orthodontic and surgical treatment) are presented. Orthodontic treatment before surgery was performed by one experienced orthodontist (AH), and orthognathic surgery was performed by one experienced surgeon (UJ), who diagnosed the syndrome according to the criteria listed in OMIM™. In the sagittal plane, the patients suffered from a mild to a very severe Angle Class III malocclusion, which was sometimes compensated by the inclination of the lower incisors; in the vertical dimension from an open bite; and transversally from a single tooth in crossbite to a circular crossbite. All patients showed dentitio tarda, some impaction, partial eruption, idopathic root resorption, transposition or other aberrations in the position of the tooth germs, and severe crowding, with sometimes parallel molar tooth buds in each quarter of the upper jaw. Because of the severity of malocclusion, orthodontic treatment needed to be performed with fixed appliances, and mainly with superelastic wires. The therapy was hampered with respect to positioning of bands and brackets because of incomplete tooth eruption, dense gingiva, and mucopolysaccharide ridges. Some teeth did not move, or moved insufficiently (especially with respect to rotations and torque) irrespective of surgical procedures or orthodontic mechanics and materials applied, and without prognostic factors indicating these problems. Establishing occlusal contact of all teeth was difficult. Tooth movement was generally retarded, increasing the duration of orthodontic treatment. Planning of extractions was different from that of patients without this syndrome. In one patient, the sole surgical procedure after orthodontic treatment with fixed appliances in the maxilla and mandible was a genioplasty. Most patients needed two- jaw surgery (bilateral sagittal split osteotomy [BSSO] with mandibular setback and distraction in the maxilla). During the period of distraction, the orthodontist guided the maxilla into final position by means of bite planes and intermaxillary elastics. To our knowledge, this is the first article in the PubMed accessible literature describing the problems with respect to interdisciplinary orthodontic and surgical procedures. Although the treatment results are not perfect, patients undergoing these procedures benefit esthetically to a high degree. Patients need to be informed with respect to the different kinds of extractions that need to be performed, the increased treatment time, and the results, which may be reached using realistic expectations

Targeted design leads to tunable photoluminescence from perylene dicarboxdiimide-poly(oxyalkylene)/siloxane hybrids for luminescent solar concentrators

A series of organic-inorganic hybrid materials in which a perylene carboxdiimide-bridged triethoxysilane (PDI-Sil) is covalently grafted to the siliceous domains of poly(oxyalkylene)/siloxane hybrids from the ureasil family has been synthesised (PDI-Sil-ureasils), with the aim of tailoring the optical properties towards their future application in luminescent solar concentrators (LSCs). Steady-state and time-resolved photoluminescence studies revealed that the ureasil host is able to isolate PDI-Sil, which inhibits the formation of aggregates. The ureasil also functions as an active host, with its intrinsic photoluminescence contributing to the optical properties of the hybrid material. Through strategic variation of the branching and molecular weight of the poly(oxyalkylene) backbone, it was shown that the efficiency of energy transfer from the ureasil host to the PDI-Sil can be modulated, which tunes the emission colour from pink to orange. The chain length, rather than the number of branches, on the poly(oxyalkylene) backbone was shown to influence the photoluminescence most significantly. Since ureasils demonstrate waveguiding properties, the results indicate that covalent grafting of a fluorophore directly to a waveguide host may provide an attractive route to more efficient LSCs

Dewetting acrylic polymer films with water/propylene carbonate/surfactant mixtures - Implications for cultural heritage conservation

7The removal of hydrophobic polymer films from surfaces is one of the top priorities of modern conservation science. Nanostructured fluids containing water, good solvents for polymers, either immiscible or partially miscible with water, and surfactants have been used in the last decade to achieve controlled removal. The dewetting of the polymer film is often an essential step to achieve efficient removal; however, the role of the surfactant throughout the process is yet to be fully understood. We report on the dewetting of a methacrylate/acrylate copolymer film induced by a ternary mixture of water, propylene carbonate (PC) and C9-11E6, a nonionic alcohol ethoxylate surfactant. The fluid microstructure was characterised through small angle X-ray scattering and the interactions between the film and water, water/PC and water/PC/C9-11E6, were monitored through confocal laser-scanning microscopy (CLSM) and analised both from a thermodynamic and a kinetic point of view. The presence of a surfactant is a prerequisite to induce dewetting of μm-thick films at room temperature, but it is not a thermodynamic driver. The amphiphile lowers the interfacial energy between the phases and favors the loss of adhesion of the polymer on glass, decreasing, in turn, the activation energy barrier, which can be overcome by the thermal fluctuations of polymer film stability, initiating the dewetting process.nonemixedBaglioni, M.; Montis, C.; Brandi, F.; GUARAGNONE, TERESA; Meazzini, I.; Baglioni, P.; Berti, D.Baglioni, M.; Montis, C.; Brandi, F.; Guaragnone, Teresa; Meazzini, I.; Baglioni, P.; Berti, D

Research data supporting "Ureasil Organic-Inorganic Hybrids as Photoactive Waveguides for Conjugated Polyelectrolyte Luminescent Solar Concentrators"

The folder “Figure 2” contains the data for the steady-state optical properties of PBS-PFP-PDI in solution (water:1,4-dioxane (1:1(v/v)) and selected doped and undoped di- and tri-ureasil LSCs in the solid-state: (a) Absorption, excitation and emission spectra of PBS-PFP-PDI (10-6 mol dm-3, λex = 360 nm, λem = 660 nm). Emission spectra of (b) DU-CPE-0, (c) DU-CPE-08 and (d) TU-CPE-08 at different excitation wavelengths and excitation spectra of (e) DU-CPE-08 and (f) TU-CPE-08 at different emission wavelengths. The folder “Figure 3” contains the data for FTIR spectra and the corresponding Gaussian curve-fits of the amide I region of (a) DU-CPE-0 and (b) TU-CPE-0. The folder “Figure 4” contains the data for emission decay curves, the corresponding fits and the instrument response function (IRF) for PBS-PFP-PDI in solution (water/1,4-dioxane (1:1 (v/v)), DU-CPE-x and TU-CPE-x at selected excitation and emission wavelengths: (a) DU-CPE-0 and TU-CPE-0 (λex = 370 nm, λem = 420 and 500 nm). (b) PBS-PFP-PDI and DU-CPE-x (λex = 370 nm, λem = 420 nm) and (c) PBS-PFP-PDI and TU-CPE-x (λex = 370 nm, λem = 420 nm). As well as the weighted residuals for each fit. The folder “Figure 5” contains the data for (a) optical power spectra of DU-CPE-0, DU-CPE-08, TU-CPE-0, TU-CPE-08 with a dark absorbing background and (e) optical power spectra of DU-LR305 and DU-PBS-LR305 with a dark absorbing background. The folder “Figure S1” contains the data for the excitation spectra of (a) DU-CPE-0 and (c) TU-CPE-0 at different emission wavelengths and the emission spectra of (b) TU-CPE-0 at different excitation wavelengths. The folder “Figure S2” contains the data for the emission spectra of (a) DU-CPE-02, (b) DU-CPE-04, (c) TU-CPE-02 and (d) TU-CPE-04 at different excitation wavelengths. The folder “Figure S3” contains the data for the excitation spectra of (a) DU-CPE-02, (b) DU-CPE-04, (c) TU-CPE-02 and (d) TU-CPE-04 at different emission wavelengths. The folder “Figure S4” contains data for the FTIR spectra and the corresponding Gaussian curve0fits of the Amide I region of (a) DU-CPE-02, (b) DU-CPE-04, (c) DU-CPE-08, (d) TU-CPE-02, (e) TU-CPE-04 and (f) TU-CPE-08 The folder “Figure S5” contains data for the emission decay curve and the corresponding fir for TU-CPE-08 (λex = 466 nm and λem = 600 nm). The fitted decay times, weighted residuals and the instrument response function are also shown. The folder “Figure S6” contains data for the emission decay curves and the corresponding fits for a (a) DU-CPE-02 (b) DU-CPE-04 and (c) DU-CPE-08 upon excitation at 370 nm (λem = 500 nm). The fitted decay times, weighted residuals and the instrument response function are also shown. The folder “Figure S7” contains data for the emission decay curves and the corresponding fits for (a) TU-CPE-02, (b) TU-CPE-04 and (c) TU-CPE-08 upon excitation at 370 nm (λem = 500 nm). The fitted decay times, weighted residuals and the instrument response function are also shown. The folder “Figure S8” contains the data for the optical pwer spectrum of the solar simulator (AM1.5G)

Research data supporting "Luminescent Solar Concentrators Based on Energy Transfer from an Aggregation-Induced Emitter Conjugated Polymer"

The folder “Figure 2” contains normalised UV/Vis absorption and emission spectra of p-O-TPE (in 50:50 by vol EtOH/THF) and PDI-Sil (in THF). The emission spectra were recorded at front-face configurations, with excitation wavelength of 380 and 520 nm used for p-O-TPE and PDI-Sil, respectively. The folder “Figure 3” contains the emission spectra (λem = 370 nm) of p-O-TPE-dU(600) with various concentrations recorded using front-face configuration (3b), PLQY of p-O-TPE-dU(600) with various concentrations measured with excitation wavelength of 400 nm (3c) and the UV/Vis transmittance spectra of p-O-TPE-dU(600) with various concentrations. The folder “Figure 4” contains the emission spectra of dU(600) ureasils (2 cm × 2 cm × 0.3 cm) measured with front-face (4a) and edge (4b) configurations, with various concentration ratios between p-O-TPE and PDI-Sil, and excitation wavelength of 370 nm. The folder “Figure S1” contains Photoluminescence excitation (λem = 650 nm) and (b) emission spectra (λex = 350 nm) of dU(600) waveguides, measured using front-face configurations. The folder “Figure S3” contains the normalised excitation spectra (a-e, λem = 650 nm) of p-O-TPE-dU(600), p-O-TPE-PDI-Sil-dU(600) and PDI-Sil-dU(600) with varying concentration ratios between p-O-TPE and PDI-Sil. A concentration ratio of 1:1 represents 0.005 wt% of p-O-TPE and 0.005 wt% of PDI-Sil. The folder “Figure S4” contains the normalised emission spectra (a-e, λex = 370 nm) of p-O-TPE-dU(600), p-O-TPE-PDI-Sil-dU(600) and PDI-Sil-dU(600) with varying concentration ratios between p-O-TPE and PDI-Sil. A concentration ratio of 1:1 represents 0.005 wt% of p-O-TPE and 0.005 wt% of PDI-Sil. The folder “Figure S7” contains the normalised emission spectra (λex = 530 nm) of PDI-Sil-dU(600) samples with varying concentrations of PDI-Sil (0.0005 to 0.05 wt%), recorded with front-face configurations. The folder “Figure S9” contains the UV/Vis transmittance spectra of dU(600), p-O-TPE-dU(600) (concentrations of p-O-TPE = 0.05 wt%), PDI-Sil-dU(600) (concentration of PDI-Sil = 0.05 wt%) and p-O-TPE-PDI-Sil-dU(600) (concentration of both p-O-TPE and PDI-Sil = 0.05 wt%). The dimension of the samples is 4.5 cm × 4.5 cm × 0.3 cm. The folder “Figure S10” contains the UV/Vis absorption spectra of dU(600), p-O-TPE-dU(600) (concentrations of p-O-TPE = 0.05 wt%), PDI-Sil-dU(600) (concentration of PDI-Sil = 0.05 wt%) and p-O-TPE-PDI-Sil-dU(600) (concentration of both p-O-TPE and PDI-Sil = 0.05 wt%). The dimension of the samples is 4.5 cm × 4.5 cm × 0.3 cm