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Papers by Daniel Grande
Design of Porous Polymeric Materials from Interpenetrating Polymer Networks (IPNs): Poly(dl-lactide)/Poly(methyl methacrylate)Based Semi-IPN Systems
Macromolecules, 2005
ABSTRACT
Polymer, 2007
The use of semi-hydrolyzable oligoester-derivatized interpenetrating polymer networks (IPNs) as n... more The use of semi-hydrolyzable oligoester-derivatized interpenetrating polymer networks (IPNs) as nanostructured precursors provides a straightforward and versatile approach toward mesoporous networks. Different poly(D,L-lactide) (PLA)/poly(methyl methacrylate) (PMMA)-based IPNs were synthesized by resorting to the so-called in situ sequential method. The PLA sub-network was first generated from a dihydroxy-telechelic PLA oligomer via an end-linking reaction with Desmodur Ò RU as a triisocyanate cross-linker. Subsequently, the methacrylic sub-network was created by free-radical copolymerization of methyl methacrylate (MMA) and a dimethacrylate (either bisphenol A dimethacrylate or diurethane dimethacrylate) with varying compositions (initial MMA/dimethacrylate composition ranging from 99/1 to 90/ 10 mol%). Both cross-linking processes were monitored by real-time infrared spectroscopy. The microphase separation developed in IPN precursors was investigated by differential scanning calorimetry (DSC). Furthermore, the quantitative hydrolysis of the PLA sub-network, under mild basic conditions, afforded porous methacrylic structures with pore sizes ranging from 10 to 100 nm eat moste thus showing the effective role of cross-linked PLA sub-chains as porogen templates. Pore sizes and pore size distributions were determined by scanning electron microscopy (SEM) and thermoporometry via DSC measurements. The mesoporosity of residual networks could be attributed to the good degree of chain interpenetration associated with both sub-networks in IPN precursors, due to their peculiar interlocking framework.
Reactive & Functional Polymers, 2003
New methacrylate monomers having a pendant photocrosslinkable bromo-substituted cinnamoyl group w... more New methacrylate monomers having a pendant photocrosslinkable bromo-substituted cinnamoyl group were synthesized by reacting corresponding hydroxy chalcones with methacryloyl chloride. These monomers were homopolymerized in ethyl methyl ketone solution using benzoyl peroxide as a free radical initiator at 70 8C. The resulting polymers were characterized 1 1 3 by UV, Fourier transform infrared, H-nuclear magnetic resonance (NMR) and C-NMR spectroscopy as well as by size-exclusion chromatography. Thermal properties of the photoreactive polymers were assessed by thermogravimetric analysis and differential scanning calorimetry. The photocrosslinking properties of the polymers were investigated in various solvents in the presence and absence of photosensitizers. The influence of solvent nature and concentration on the rate of photocrosslinking of the newly synthesized polymers were studied for using the latter as negative photoresist materials.
Polymer, 2004
New photoreactive homo-and copolymers containing pendant chlorocinnamoyl moieties were respective... more New photoreactive homo-and copolymers containing pendant chlorocinnamoyl moieties were respectively synthesized by homopolymerization of corresponding acrylic monomer and copolymerization with glycidyl methacrylate. The diverse structures were characterized by different spectroscopic techniques. The thermal properties of the photosensitive polymers were investigated by thermogravimetric analysis in air and differential scanning calorimetry under nitrogen atmosphere. The compositions of polymers were determined by 1 H-NMR analysis. The reactivity ratios of both comonomers were calculated using the conventional linearization methods such as Fineman-Ross, Kelen-Tudos, extended Kelen -Tudos and a non-linear error-in-variables model (EVM) method using a computer program, RREVM, in order to optimize the reaction conditions for industrial applications. The photoreactivity of newly synthesized homoand copolymers containing pendant chlorocinnamoyl moieties was investigated in solution as well as in thin films. The effects of solvent nature, concentration, temperature, copolymer compositions and photosensitizers on the rate of photocrosslinking of these new photoresponsive polymers were evaluated. Suitable conditions were discussed for using as negative photoresists in industries. q
Design of Porous Polymeric Materials from Interpenetrating Polymer Networks (IPNs): Poly(dl-lactide)/Poly(methyl methacrylate)Based Semi-IPN Systems
Macromolecules, 2005
ABSTRACT
Polymer, 2007
The use of semi-hydrolyzable oligoester-derivatized interpenetrating polymer networks (IPNs) as n... more The use of semi-hydrolyzable oligoester-derivatized interpenetrating polymer networks (IPNs) as nanostructured precursors provides a straightforward and versatile approach toward mesoporous networks. Different poly(D,L-lactide) (PLA)/poly(methyl methacrylate) (PMMA)-based IPNs were synthesized by resorting to the so-called in situ sequential method. The PLA sub-network was first generated from a dihydroxy-telechelic PLA oligomer via an end-linking reaction with Desmodur Ò RU as a triisocyanate cross-linker. Subsequently, the methacrylic sub-network was created by free-radical copolymerization of methyl methacrylate (MMA) and a dimethacrylate (either bisphenol A dimethacrylate or diurethane dimethacrylate) with varying compositions (initial MMA/dimethacrylate composition ranging from 99/1 to 90/ 10 mol%). Both cross-linking processes were monitored by real-time infrared spectroscopy. The microphase separation developed in IPN precursors was investigated by differential scanning calorimetry (DSC). Furthermore, the quantitative hydrolysis of the PLA sub-network, under mild basic conditions, afforded porous methacrylic structures with pore sizes ranging from 10 to 100 nm eat moste thus showing the effective role of cross-linked PLA sub-chains as porogen templates. Pore sizes and pore size distributions were determined by scanning electron microscopy (SEM) and thermoporometry via DSC measurements. The mesoporosity of residual networks could be attributed to the good degree of chain interpenetration associated with both sub-networks in IPN precursors, due to their peculiar interlocking framework.
Reactive & Functional Polymers, 2003
New methacrylate monomers having a pendant photocrosslinkable bromo-substituted cinnamoyl group w... more New methacrylate monomers having a pendant photocrosslinkable bromo-substituted cinnamoyl group were synthesized by reacting corresponding hydroxy chalcones with methacryloyl chloride. These monomers were homopolymerized in ethyl methyl ketone solution using benzoyl peroxide as a free radical initiator at 70 8C. The resulting polymers were characterized 1 1 3 by UV, Fourier transform infrared, H-nuclear magnetic resonance (NMR) and C-NMR spectroscopy as well as by size-exclusion chromatography. Thermal properties of the photoreactive polymers were assessed by thermogravimetric analysis and differential scanning calorimetry. The photocrosslinking properties of the polymers were investigated in various solvents in the presence and absence of photosensitizers. The influence of solvent nature and concentration on the rate of photocrosslinking of the newly synthesized polymers were studied for using the latter as negative photoresist materials.
Polymer, 2004
New photoreactive homo-and copolymers containing pendant chlorocinnamoyl moieties were respective... more New photoreactive homo-and copolymers containing pendant chlorocinnamoyl moieties were respectively synthesized by homopolymerization of corresponding acrylic monomer and copolymerization with glycidyl methacrylate. The diverse structures were characterized by different spectroscopic techniques. The thermal properties of the photosensitive polymers were investigated by thermogravimetric analysis in air and differential scanning calorimetry under nitrogen atmosphere. The compositions of polymers were determined by 1 H-NMR analysis. The reactivity ratios of both comonomers were calculated using the conventional linearization methods such as Fineman-Ross, Kelen-Tudos, extended Kelen -Tudos and a non-linear error-in-variables model (EVM) method using a computer program, RREVM, in order to optimize the reaction conditions for industrial applications. The photoreactivity of newly synthesized homoand copolymers containing pendant chlorocinnamoyl moieties was investigated in solution as well as in thin films. The effects of solvent nature, concentration, temperature, copolymer compositions and photosensitizers on the rate of photocrosslinking of these new photoresponsive polymers were evaluated. Suitable conditions were discussed for using as negative photoresists in industries. q