Search results for "Photopolymer"
showing 10 items of 33 documents
Cast multibilayer films from polymerizable lipids
1987
Controlled synthesis of poly(acetone oxime acrylate) as a new reactive polymer: Stimuli-responsive reactive copolymers
2007
Abstract Acetone oxime acrylate has been synthesized as a new active ester monomer. Free radical polymerization yielded a reactive polymer soluble in various organic solvents, such as chloroform, dioxane, DMSO, acetone, methanol, dichloromethane, DMF, and ethanol. Controlled radical polymerization of acetone oxime acrylate was successfully conducted using the RAFT, NMP and Iniferter method. Partly polymer analogous reaction with N-isopropylamine resulted in the reactive copolymer poly(N-isopropylacrylamide-co-acetone oxime acrylate), which featured a lower critical solution temperature (LCST) of 61 °C in water. Further, the reactivity of the copolymer was exemplary proven by complete reacti…
Photochemistry of 7-acetoxybenzopyran derivatives. Synthesis of eupatoriochromene and encecalin
1989
Abstract The photolysis of the 7-acetoxybenzopyran derivatives 1a-5a has been carried out. Chromene 1a was found to undergo extensive photopolymerization. Chromanone 2a underwent a rather inefficient photo-Fries rearrangement to the 6 - and 8 - acetyl derivatives 2b and 2c . Diacetoxychromene 3a gave the unsaturated ketone 8 as the main product, besides its deacetylation analogue 9 and chromanone 11 . Diacetoxychroman 4a afforded a mixture of four C-acetyl products: 1b, 1c, 2b and 2c , together with Chromene 1a and chromanone 2a. Finally, irradiation of chroman 5a gave rise to a mixture of the two possible photo-Fries products 5b (43%) and 5c (52%). The mechanistic implications of the above…
Photoimaging through in-Situ Photopolymerization of Heterobifunctional Mesogenic Compounds in Liquid Crystalline State
2007
A series of heterobifunctional mesogenic biphenyl esters having two different polymerizable groups, i.e., acryl and diacetylene groups, were synthesized and their thermal behaviors and polymerization investigated. All compounds showed enantiotropic transitions. Under POM, highly birefringent focal-conic fan textures appeared on heating and cooling from the isotropic melt. Compounds 6−8 having a butyl spacer between a biphenyl and a diacetylene group exhibited LC phases even at room temperature. The X-ray diffractograms of compounds 6−8 showed a set of reflections in the small-angle region. They consisted of more than three sharp diffraction peaks with d spacings in the ratio of 1:1/2:1/3, s…
Oligothiophenes for Pattern Formation by Stamping
2003
Oligothiophene monomers with a fixed length varying from 3 to 5 thiophene rings were prepared by Stille coupling. They were functionalised with one or two methacrylate groups to allow polymerization and cross-linking. These monomers can be patterned with the help of soft silicon stamps (e.g., with the micro-injection moulding in capillaries process) on substrates like glass or flexible polymer foils. If a photoinitiator has been added, they can then be hardened by exposure to UV-light through the transparent stamp. Afterwards the stamp can be removed. This allows the preparation of several centimeters long oligothiophene lines of a width varying between 50 and 0.5 μm. These lines of semicon…
Synthèse et formulation de résines photopolymérisables issues de la biomasse : application pour l'impression Braille
2014
The work of the PhD deals with the synthesis of polymerizable monomers derived from biomass, the study of their photopolymerization and the characterization of the resulting materials. The formulated monomers were tested in a printing method of Braille characters.The monomers were prepared in a two-steps reaction that is simple, economic and environmentally friendly. The first step comprised a reaction between glycerol derivatives (glycerol carbonate or glycidol) and fatty acids. In the second step, the obtained [alpha]-monoglycerides were functionalized to obtain photopolymerizable monomers. The different obtained monomers that bear (meth)acrylate and/or epoxy groups were photopolymerized …
New biodegradable hydrogels based on a photo-cross-linkable polyaspartamide and poly(ethylene glycol) derivatives. Release studies of an anticancer d…
2001
The functionalization of α,β-poly(N-2-hydroxyethyl)-dl-aspartamide (PHEA) with glycidyl methacrylate (GMA) gives rise to a water-soluble photosensitive copolymer PHEA-GMA (PHG). Aqueous solutions of PHG alone or in combination with various concentrations of poly(ethylene glycol) dimethacrylate or poly(ethylene glycol) diacrylate (PEGDA) have been exposed to a source of UV rays at 313 nm in order to obtain polymeric networks. All samples have been prepared both as water-swellable microparticles and as gel systems. Microparticles have been characterised by Fourier transform IR spectrophotometry, dimensional analysis and swelling measurements in aqueous media mimicking biological fluids. In vi…
Undecylenic acid: A tunable bio-based synthon for materials applications
2016
International audience; An undecylenic acid-based monoglyceride prepared from glycidol and undecylenic acid is used as suitable and tunable synthon for polymerization applications. Epoxidation and acrylation reactions lead to photopolymerizable monomers while transesterification with dimethyl carbonate, metathesis and aminolysis reactions provide access to polyhydroxyurethane-based materials. The successive intermediates were synthesized according to a green chemistry approach implicating solvent-less and catalyzed reactions, and were at each step fully characterized by infrared, 1H and 13C{1H} NMR spectroscopy, elemental analysis and mass spectrometry. Analyses of the resulting polymer mat…
Designed biodegradable hydrogel structures prepared by stereolithography using poly(ethylene glycol)/poly(D,L-lactide)-based resins
2010
Designed three-dimensional biodegradable poly(ethylene glycol)/poly(D,L-lactide) hydrogel structures were prepared for the first time by stereolithography at high resolutions. A photo-polymerisable aqueous resin comprising PDLLA-PEG-PDLLA-based macromer, visible light photo-initiator, dye and inhibitor in DMSO/water was used to build the structures. Porous and non-porous hydrogels with well-defined architectures and good mechanical properties were prepared. Porous hydrogel structures with a gyroid pore network architecture showed narrow pore size distributions, excellent pore interconnectivity and good mechanical properties. The structures showed good cell seeding characteristics, and human…
1987
Preparation de vesicules contenant une matrice polymere reticule hydrophile (couches bimoleculaires phospholipides revetues de microparticules polymeres)