26
|
Peeterbroeck S, Alexandre M, Jérôme R, Dubois P. Poly(ethylene-co-vinyl acetate)/clay nanocomposites: Effect of clay nature and organic modifiers on morphology, mechanical and thermal properties. Polym Degrad Stab 2005. [DOI: 10.1016/j.polymdegradstab.2005.03.023] [Citation(s) in RCA: 107] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
27
|
Riva R, Lenoir S, Jérôme R, Lecomte P. Functionalization of poly(ε-caprolactone) by pendant hydroxyl, carboxylic acid and epoxide groups by atom transfer radical addition. POLYMER 2005. [DOI: 10.1016/j.polymer.2005.03.105] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
28
|
Blacher S, Maquet V, Jérôme R, Pirard JP, Boccaccini AR. Study of the connectivity properties of Bioglass -filled polylactide foam scaffolds by image analysis and impedance spectroscopy. Acta Biomater 2005; 1:565-74. [PMID: 16701836 DOI: 10.1016/j.actbio.2005.06.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2004] [Revised: 06/06/2005] [Accepted: 06/07/2005] [Indexed: 11/16/2022]
Abstract
The porous structure of two series of poly(D,L-lactide)/Bioglass composite foams prepared by thermal-induced phase separation was investigated by image analysis and impedance spectroscopy. Polymer solutions of either low or high molecular weight containing different concentrations (up to 50 wt.%) of Bioglass particles of mean particle size d < 5 microm were studied. The morphology of both macro- and micropores was studied by scanning electron microscopy and image analysis of both neat and composite foams (containing 10-50 wt.% Bioglass). The pore connectivity of both neat polymer and composite foams was characterized by impedance spectroscopy in relation with their transport properties. The influence of the foam composition (i.e., polymer molecular weight and concentration of Bioglass on pore microstructure was studied using these non-destructive methods. It was found that addition of Bioglass particles has a pronounced effect on pore orientation, leading to increasing loss of order of pore structure, especially for low-molecular weight PDLLA foams.
Collapse
|
29
|
Vangeyte P, Leyh B, De Clercq C, Auvray L, Misselyn-Bauduin AM, Jérôme R. Concomitant adsorption of poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers and sodium dodecyl sulfate at the silica-water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:7710-6. [PMID: 16089373 DOI: 10.1021/la047051k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Upon addition of silica to aqueous solutions of poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers (PEO-b-PCL) and sodium dodecyl sulfate (SDS), adsorption of the solutes occurs at the silica-water interface. The amount of the adsorbed constituents has been measured by the total concentration depletion method. Small-angle neutron scattering experiments (SANS) have been carried out to investigate the structure of the adsorbed layer. Although SDS is not spontaneously adsorbed onto hydrophilic silica, adsorption is observed in the presence of PEO-b-PCL diblocks, in relation to the relative concentration of the two compounds. Conversely, SDS has a depressive effect on the adsorption of the copolymer, whose structure at the interface is modified. Copolymer desorption is however never complete at high SDS content. These observations have been rationalized by the associative behavior of PEO-b-PCL and SDS in water.
Collapse
|
30
|
Jérôme C, Jérôme R. Tailoring of Thin Polymer Films Chemisorbed onto Conductive Surfaces by Electrografting. ACTA ACUST UNITED AC 2005. [DOI: 10.1021/bk-2005-0912.ch006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
|
31
|
Vangeyte P, Leyh B, Rojas OJ, Claesson PM, Heinrich M, Auvray L, Willet N, Jérôme R. Adsorption of poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers at the silica-water interface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:2930-2940. [PMID: 15779968 DOI: 10.1021/la047425+] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The adsorption of amphiphilic poly(ethylene oxide)-b-poly(epsilon-caprolactone) and poly(ethylene oxide)-b-poly(gamma-methyl-epsilon-caprolactone) copolymers in aqueous solution on silica and glass surfaces has been investigated by flow microcalorimetry, small-angle neutron scattering (SANS), surface forces, and complementary techniques. The studied copolymers consist of a poly(ethylene oxide) (PEO) block of M(n) = 5000 and a hydrophobic polyester block of poly(epsilon-caprolactone) (PCL) or poly(gamma-methyl-epsilon-caprolactone) (PMCL) of M(n) in the 950-2200 range. Compared to homoPEO, the adsorption of the copolymers is significantly increased by the connection of PEO to an aliphatic polyester block. According to calorimetric experiments, the copolymers interact with the surface mainly through the hydrophilic block. At low surface coverage, the PEO block interacts with the surface such that both PEO and PCL chains are exposed to the aqueous solution. At high surface coverage, a dense copolymer layer is observed with the PEO blocks oriented toward the solution. The structure of the copolymer layer has been analyzed by neutron scattering using the contrast matching technique and by tapping mode atomic force microscopy. The experimental observations agree with the coadsorption of micelles and free copolymer chains at the interface.
Collapse
|
32
|
Peeterbroeck S, Alexandre M, Nagy J, Moreau N, Destrée A, Monteverde F, Rulmont A, Jérôme R, Dubois P. Polymer Layered Silicate/Carbon Nanotube Nanocomposites: Morphological and Rheological Properties. ACTA ACUST UNITED AC 2005. [DOI: 10.1002/masy.200550312] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
33
|
Harrats C, Jérôme R. Block balance in hydrogenated polybutadiene-b-polymethylmethacrylate diblock copolymer for efficient interfacial activity in low-density polyethylene/polymethylmethacrylate blend: Phase morphology development. ACTA ACUST UNITED AC 2005. [DOI: 10.1002/polb.20365] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
34
|
Boccaccini A, Blaker J, Maquet V, Day R, Jérôme R. Preparation and characterisation of poly(lactide-co-glycolide) (PLGA) and PLGA/Bioglass® composite tubular foam scaffolds for tissue engineering applications. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2005. [DOI: 10.1016/j.msec.2004.03.002] [Citation(s) in RCA: 118] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
35
|
Rieger J, Van Butsele K, Lecomte P, Detrembleur C, Jérôme R, Jérôme C. Versatile functionalization and grafting of poly(ε-caprolactone) by Michael-type addition. Chem Commun (Camb) 2005:274-6. [PMID: 15724210 DOI: 10.1039/b411565a] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The Michael-type addition of aliphatic (co)polyesters onto gamma-acryloyloxy epsilon-caprolactone units is a very straightforward technique of functionalization and grafting, which is tolerant to a variety of functional groups and does not require intermediate protection/deprotection steps.
Collapse
|
36
|
Maquet V, Boccaccini AR, Pravata L, Notingher I, Jérôme R. Porous poly(alpha-hydroxyacid)/Bioglass composite scaffolds for bone tissue engineering. I: Preparation and in vitro characterisation. Biomaterials 2004; 25:4185-94. [PMID: 15046908 DOI: 10.1016/j.biomaterials.2003.10.082] [Citation(s) in RCA: 280] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2002] [Accepted: 10/10/2003] [Indexed: 11/21/2022]
Abstract
Highly porous composites scaffolds of poly-D,L-lactide (PDLLA) and poly(lactide-co-glycolide) (PLGA) containing different amounts (10, 25 and 50 wt%) of bioactive glass (45S5 Bioglass)were prepared by thermally induced solid-liquid phase separation (TIPS) and subsequent solvent sublimation. The addition of increasing amounts of Bioglass into the polymer foams decreased the pore volume. Conversely, the mechanical properties of the polymer materials were improved. The composites were incubated in phosphate buffer saline at 37 degrees C to study the in vitro degradation of the polymer by measurement of water absorption, weight loss as well as changes in the average molecular weight of the polymer and in the pH of the incubation medium as a function of the incubation time. The addition of Bioglass to polymer foams increased the water absorption and weight loss compared to neat polymer foams. However, the polymer molecular weight, determined by size exclusion chromatography, was found to decrease more rapidly and to a larger extent in absence of Bioglass. The presence of the bioactive filler was therefore found to delay the degradation rate of the polymer as compared to the neat polymer foams. Formation of hydroxyapatite on the surface of composites, as an indication of their bioactivity, was recorded by EDXA, X-ray diffractometry and confirmed by Raman spectroscopy.
Collapse
|
37
|
Rieger J, Bernaerts KV, Du Prez FE, Jérôme R, Jérôme C. Lactone End-Capped Poly(ethylene oxide) as a New Building Block for Biomaterials. Macromolecules 2004. [DOI: 10.1021/ma048768h] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
38
|
Voccia S, Bech L, Gilbert B, Jérôme R, Jérôme C. Preparation of poly(epsilon-caprolactone) brushes at the surface of conducting substrates. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:10670-10678. [PMID: 15544400 DOI: 10.1021/la048357u] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This paper reports on the preparation of polyester brushes at the surface of electrically conducting materials. A two-step strategy has been worked out that consists of the electropolymerization of an acrylate under a cathodic potential, such that the polyacrylate layer is chemisorbed at the surface. In a second step, either preformed poly(epsilon-caprolactone) chains are grafted onto the polyacrylate sublayer or the ring-opening polymerization of epsilon-caprolactone is initiated from it.
Collapse
|
39
|
Harrats C, Benabdallah T, Groeninckx G, Jérôme R. Stress-strain behavior of low-density polyethylene/poly(methyl methacrylate) blends with modulated interfaces with a hydrogenated polybutadiene-block-poly(methyl methacrylate) diblock copolymer. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/polb.20300] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
40
|
Stassin F, Jérôme R. Contribution of Supercritical CO2to the Preparation of Aliphatic Polyesters and Materials Thereof. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/masy.200451310] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
41
|
Hrobarikova J, Robert JL, Calberg C, Jérôme R, Grandjean J. Solid-state NMR study of intercalated species in poly(epsilon-caprolactone)/clay nanocomposites. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:9828-9833. [PMID: 15491221 DOI: 10.1021/la048705s] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The structure and dynamics of surfactant and polymer chains in intercalated poly(epsilon-caprolactone)/clay nanocomposites are characterized by (31)P magic-angle spinning (MAS) and (13)C cross-polarization MAS NMR techniques. To obtain hybrid materials with the low polymer content required for this study, in situ intercalative polymerization was performed by adapting a published procedure. After nanocomposite formation, the chain motion of the surfactant is enhanced in the saponite-based materials but reduced in the Laponite ones. Compared to the starting clay, the trans conformer population of the surfactant hydrocarbon chain in the nanocomposite decreases for the saponite systems. Mobility of the polymer chain is higher in the nanocomposites than in the bulk phase. The charge of the modified saponite does not significantly influence chain mobility in the nanocomposites.
Collapse
|
42
|
Vangeyte P, Leyh B, Auvray L, Grandjean J, Misselyn-Bauduin AM, Jérôme R. Mixed self-assembly of poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers and sodium dodecyl sulfate in aqueous solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:9019-9028. [PMID: 15461482 DOI: 10.1021/la048848e] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Interaction of amphiphilic poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers with anionic sodium dodecyl sulfate (SDS) has been investigated in aqueous solution. Formation of mixed micelles has been confirmed by surface tension measurements, whereas the influence of the surfactant on the copolymer self-assembling has been studied by measurement of the 1H NMR self-diffusion coefficients and by small-angle neutron scattering. As a rule, the surfactant decreases the heterogeneity of the micellar structures formed by the copolymer in water. Moreover, increasing the content of SDS results in the increasingly more important extension of the poly(ethylene oxide) (PEO) corona chains and the copolymer micelle deaggregation. The stability of the micelles against SDS increases with the length of the hydrophobic block. Preliminary two-dimensional NMR measurements with nuclear Overhauser enhancement have confirmed the spatial vicinity between SDS and the constitutive blocks of the copolymer.
Collapse
|
43
|
Vangeyte P, Leyh B, Heinrich M, Grandjean J, Bourgaux C, Jérôme R. Self-assembly of poly(ethylene oxide)-b-poly(epsilon-caprolactone) copolymers in aqueous solution. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:8442-8451. [PMID: 15379459 DOI: 10.1021/la049695y] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The associative behavior of monodisperse diblock copolymers consisting of a hydrophilic poly(ethylene oxide) block and a hydrophobic poly(epsilon-caprolactone) or poly(gamma-methyl-epsilon-caprolactone) block has been studied in aqueous solution. Copolymers have been directly dissolved in water. The solution properties have been studied by surface tension, in relation to mesoscopic analyses by NMR (self-diffusion coefficients), transmission electron microscopy, and small-angle neutron and X-ray scattering. The experimental results suggest that micellization occurs at low concentration (approximately 0.002 wt %) and results in a mixture of unimers and spherical micelles that exchange slowly. The radius of the micelles has been measured (ca. 11 nm), and the micellar substructure has been extracted from the fitting of the SANS data with two analytical models. The core radius and the aggregation number change with the hydrophobic block length according to scaling laws as reported in the scientific literature. The poly(ethylene oxide) blocks are in a moderately extended conformation in the corona, which corresponds to about 25% of the completely extended chain. No significant modification is observed when poly(gamma-methyl-epsilon-caprolactone) replaces poly(epsilon-caprolactone) in the diblocks.
Collapse
|
44
|
Abraham T, Christendat D, Xu Z, Masliyah J, Gohy JF, Jérôme R. Role of polyelectrolyte charge density in tuning colloidal forces. AIChE J 2004. [DOI: 10.1002/aic.10255] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
45
|
Deumens R, Koopmans GC, Den Bakker CGJ, Maquet V, Blacher S, Honig WMM, Jérôme R, Pirard JP, Steinbusch HWM, Joosten EAJ. Alignment of glial cells stimulates directional neurite growth of CNS neurons in vitro. Neuroscience 2004; 125:591-604. [PMID: 15099673 DOI: 10.1016/j.neuroscience.2004.02.010] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/10/2004] [Indexed: 11/25/2022]
Abstract
Olfactory ensheathing cells (OECs) together with olfactory nerve fibroblasts (ONFs) and neonatal astrocytes are potent stimulators of neurite growth in adulthood and during development, respectively. Since it is known that alignment of glial cells is important for the correct outgrowth of axon tracts, it was hypothesized that the alignment of glial cells stimulates directional and enhanced neurite outgrowth. Adult OEC/ONF and neonatal astrocytes were cultured either on biodegradable poly(d,l)-lactide matrices or in Petri dishes for 4 days. Thereafter neonatal cerebral cortical neurons were added. After a 2-days coculture period the cultures were fixed and processed for a combined MAP-2 and phosphorylated neurofilament (RT97) staining. The neurite growth (neurite elongation and neurite formation) and the neurite direction were assessed. We show that (1). OEC/ONF cultures are more potent in stimulating the length of the longest neurite of cocultured neurons, (2). alignment of glial is achieved in vitro on our biomatrices, (3). aligned glial/biomatrix complexes do not enhance neurite growth, and (4). aligned glial/biomatrix complexes direct neurite outgrowth. These data have significant implications for in vivo experiments focusing on glial transplantation. Transplanting glial/biomatrix complexes may stimulate the directional regrowth of severed axons across a lesion site.
Collapse
|
46
|
Lecomte P, Stassin F, Jérôme R. Recent Developments in the Ring-Opening Polymerization ofε-Caprolactone and Derivatives Initiated by Tin(IV) Alkoxides. ACTA ACUST UNITED AC 2004. [DOI: 10.1002/masy.200451125] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
47
|
Koulic C, François G, Jérôme R. Formation of Polyamide 12−Polyisoprene Core−Shell Particles in Polystyrene by Reactive Blending. Macromolecules 2004. [DOI: 10.1021/ma035826a] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
48
|
Lenoir S, Riva R, Lou X, Detrembleur C, Jérôme R, Lecomte P. Ring-Opening Polymerization of α-Chloro-ε-caprolactone and Chemical Modification of Poly(α-chloro-ε-caprolactone) by Atom Transfer Radical Processes. Macromolecules 2004. [DOI: 10.1021/ma035003l] [Citation(s) in RCA: 116] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
49
|
Vankan R, Fayt R, Jérôme R, Teyssié P. Contribution of polyalkyl(meth)acrylates to the design of PVC melt viscosity. POLYM ENG SCI 2004. [DOI: 10.1002/pen.10564] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
50
|
Jacobsen S, Fritz HG, Degée P, Dubois P, Jérôme R. Polylactide (PLA)-a new way of production. POLYM ENG SCI 2004. [DOI: 10.1002/pen.11518] [Citation(s) in RCA: 154] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|