Polymethylmethacrylate by XPS

Wang

Dental Materials Journal

et al. 2015

Atmospheric-pressure cold plasma was applied to process the surface of heat-polymerized acrylic resin. Changes to the physical properties and early adherence of Candida albicans were investigated. Alternating current cold plasma with Ar/O2 as working gas was used. Scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) were employed to study the possible mechanism. Experimental results showed that after plasma treatment, the contact angle of acrylic resin significantly decreased. There were no significant differences in roughness, flexural strength and elasticity modulus, but microhardness was significant improved in the treated group. More importantly, the early adherence of Candida albicans on the surface was reduced after plasma treatment. Cold plasma seemed to be a promising and convenient strategy of preventing the early adherence of Candida albicans on acrylic resins, which would greatly benefit potential dental applications.

Section: Semmentioning

confidence: 99%

“…6a). Peaks near 284.8, 286.1, and 288.5 eV were respectively assigned to the functional groups of C-C-H, O-CH 3 and O-C=O 25,26) detected on the acrylic resin surface. After Fig.…”

Section: Semmentioning

confidence: 99%

Cold plasma-induced surface modification of heat-polymerized acrylic resin and prevention of early adherence of <i>Candida albicans </i>

Wang

Dental Materials Journal

et al. 2015

“…The ratio of the O1s to C1s is 0.31 ± 0.00, which correlates well with ordered PMMA surface groups. 56 After applying azide 1, irradiating and washing, the XPS spectrum of the surface showed additional peaks at 407.1, 695.8, and 625.0 eV, which correspond to N1s, F1s and I3d5, respectively. The ratio of the O1s to C1s in PMMA modified with azide 1 decreased approximately 50% when compared to native PMMA.…”

Section: Resultsmentioning

confidence: 99%

Photochemical Functionalization of Polymer Surfaces for Microfabricated Devices

et al. 2008

Herein we report the topochemical modification of polymer surfaces with perfluorinated aromatic azides. The aryl azides, which have quaternary amine or aldehyde functional groups, were linked to the surface of the polymer by UV irradiation. The polymer substrates used in this study were cyclic olefin copolymer and poly(methyl methacrylate). These substrates were characterized before and after modification using reflection-absorption infrared spectroscopy, sessile water contact angle measurements, and X-ray photoelectron spectroscopy. Analysis of the surface confirmed the presence of aromatic groups with aldehyde or quaternary amine functionality. Enzyme immobilization and patterning onto polymer surfaces were studied using confocal microscopy. Enzymatic digests of protein were carried out on modified probes manufactured from thermoplastic substrates, and the resulting peptide analysis was completed using matrix-assisted laser desorption/ionization mass spectrometry. The use of functionalized perfluorinated aromatic azides allows the surface chemistry of thermoplastics to be tailored for specific lab-on-a-chip applications.

Beilstein J. Nanotechnol.

“…5 ,b shows the C 1s HAXPES spectra acquired with 3000 eV photons together with the deconvolution using least-square fits after background subtraction. Both spectra show the characteristic 287.5 eV (continuous green line) and 290 eV (continuous magenta line) peaks of PMMA, corresponding to O–CH 3 and O–C=O configurations, respectively, with a 1:1 stoichiometric relationship [ 21 ]. The continuous red and blue lines correspond to C–C/C–H bonding and to hydroxyl bonding, respectively, as described in Fig.…”

Section: Resultsmentioning

confidence: 99%

Identifying the nature of surface chemical modification for directed self-assembly of block copolymers

Evangelio¹,

Gramazio²,

Lorenzoni³

et al. 2017

In recent years, block copolymer lithography has emerged as a viable alternative technology for advanced lithography. In chemical-epitaxy-directed self-assembly, the interfacial energy between the substrate and each block copolymer domain plays a key role on the final ordering. Here, we focus on the experimental characterization of the chemical interactions that occur at the interface built between different chemical guiding patterns and the domains of the block copolymers. We have chosen hard X-ray high kinetic energy photoelectron spectroscopy as an exploration technique because it provides information on the electronic structure of buried interfaces. The outcome of the characterization sheds light onto key aspects of directed self-assembly: grafted brush layer, chemical pattern creation and brush/block co-polymer interface.