Ghislain David

Bio: Ghislain David is an academic researcher from Centre national de la recherche scientifique. The author has contributed to research in topics: Radical polymerization & Monomer. The author has an hindex of 28, co-authored 120 publications receiving 2891 citations. Previous affiliations of Ghislain David include Commissariat à l'énergie atomique et aux énergies alternatives & École Normale Supérieure.

Biobased thermosetting epoxy: present and future.

Abstract: Reḿi Auvergne,† Sylvain Caillol,† Ghislain David,*,† Bernard Boutevin,† and Jean-Pierre Pascault‡,§ †Institut Charles Gerhardt UMR CNRS 5253 Laboratoire Ingeńierie et Architecture Macromolećulaire, Ecole Nationale Supeŕieure de Chimie de Montpellier, 8 rue de l’Ecole Normale, 34296 Montpellier Cedex 05, France ‡INSA-Lyon, IMP, UMR5223, F-69621, Villeurbanne, France Universite ́ de Lyon, F-69622, Lyon, France

Use of iodocompounds in radical polymerization.

Abstract: Iodocompounds are highly attractive as potential intermediates for the synthesis of various organic and macromolecular molecules because of the ability of the iodine atom to be a good leaving atom. In addition, they are efficient transfer agents in radical polymerization. In fact, the ability of the iodine atom to transfer onto growing macromolecular chains allowed the development of such compounds. An important class of iodocompounds employed as chain transfer agents (CTAs) are the fluorinated iodocompounds, R FI. These compounds could be obtained in good yield by simple addition of either HI or ICl onto fluorovinylic monomers. These fluorinated CTAs enabled both initiation of the polymerization under UV, thermally or in the presence of redox catalysis, and transfer of the iodine atom onto the growing chains. Oligomers of low molar masses could then be obtained. Then, in the late 1970s, Tatemoto 1 pened the route to the iodine transfer polymerization (ITP). Hence, by using an initiating radical, iodofluorocompounds could enter in a controlled process, based on a degenerative transfer (DT). This real breakthrough was first realized with fluoroolefin monomers but was rapidly extended to other common nonhalogenated vinyl monomers. For specific applications, nonfluorinated CTAs were preferred. Some iodoalkanes, such as iodoform, were then investigated in the ITP process. Recently, reverse iodine transfer polymerization (RITP), another DT process, was discovered by us and is based on the use of molecular iodine. It was thus of interest to deeper summarize the synthesis and the use of iodinated derivatives involved in telomerization, ITP, and RITP, and these are the objectives of this review, divided in four main parts. The first part reports the syntheses of such iodocompounds, fluorinated and nonfluorinated ones. The structural requirements are also investigated for further efficient transfer reactions. The following parts describe their uses in several radical processes, i.e., telomerization, ITP, and RITP. A wide range of vinyl monomers (halogenated and nonhalogenated) have been involved in these radical techniques. Then, syntheses of well-architectured copolymers (especially block * To whom correspondence should be addressed. Tel: (0033)4 67 14 43 01. Fax: (0033)4 67 14 72 20. E-mail: bernard.boutevin@enscm.fr. 3936 Chem. Rev. 2006, 106, 3936−3962

New Fluorinated Polymers Bearing Pendant Phosphonic Acid Groups. Proton Conducting Membranes for Fuel Cell

Abstract: The synthesis and characterizations of original fluorinated copolymers bearing phosphonic acid side functions for novel membranes potentially involved in fuel cell applications are presented. These copolymers were obtained by chemical modifications of various poly(CTFE-alt-IEVE) and poly[(CTFE-alt-IEVE)-co-(CTFE-EVE)] terpolymers (where CTFE, IEVE, and EVE stand for chlorotrifluoroethylene, 2-iodoethyl vinyl ether, and ethyl vinyl ether) via the Arbuzov reaction. Then, the hydrolysis of the phosphonate moieties into phosphonic acid groups was carried out quantitatively in mild conditions, in the presence of bromotrimethylsilane. The ionic exchange capacities (IECs) determined by potentiometric titration were ranging from 2.9 to 6.8 mequiv/g. The thermal and electrochemical properties of the resulting membranes (processed by casting) were investigated. Whatever the phosphonic acid content, the main degradation started from 250 °C, showing a high thermo-oxidative stability of these copolymers. At 25 °C and ...

From a bio-based phosphorus-containing epoxy monomer to fully bio-based flame-retardant thermosets

Abstract: In this work, phloroglucinol was used as a renewable resource to prepare an epoxy monomer and phosphorus containing reactive flame retardant (FR). These building blocks were reacted with diamines to obtain partly or fully bio-based flame retardant epoxy resins. It was highlighted that the glass transition temperature of the materials was tightly related to the functionality of the reactive monomers and the resulting crosslink density. Thermal stability and char yield of the thermosets seems to be mainly governed by the aromaticity of the monomers, the linking rate of the aromatic ring and the phosphorus content. Phosphorus FR are more efficient in intrinsically poorly charring matrices. It was evidenced that the flammability of bio-based epoxies can be monitored by two strategies: (i) choosing bio-based monomers with high charring ability and low combustion energy, (ii) incorporating bio-based phosphorus-containing reactive FR in the polymer network.

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Bright Side of Lignin Depolymerization: Toward New Platform Chemicals

Abstract: Lignin, a major component of lignocellulose, is the largest source of aromatic building blocks on the planet and harbors great potential to serve as starting material for the production of biobased products. Despite the initial challenges associated with the robust and irregular structure of lignin, the valorization of this intriguing aromatic biopolymer has come a long way: recently, many creative strategies emerged that deliver defined products via catalytic or biocatalytic depolymerization in good yields. The purpose of this review is to provide insight into these novel approaches and the potential application of such emerging new structures for the synthesis of biobased polymers or pharmacologically active molecules. Existing strategies for functionalization or defunctionalization of lignin-based compounds are also summarized. Following the whole value chain from raw lignocellulose through depolymerization to application whenever possible, specific lignin-based compounds emerge that could be in the fu...

Transition metal-catalyzed living radical polymerization : toward perfection in catalysis and precision polymer synthesis

Abstract: 2.1.6. Tacticity and Sequence: Advanced Control 4967 2.2. Transition Metal Catalysts 4967 2.2.1. Overviews of Catalysts 4967 2.2.2. Ruthenium 4967 2.2.3. Copper 4971 2.2.4. Iron 4971 2.2.5. Nickel 4975 2.2.6. Molybdenum 4975 2.2.7. Manganese 4976 2.2.8. Osmium 4976 2.2.9. Cobalt 4976 2.2.10. Other Metals 4976 2.3. Cocatalysts (Additives) 4977 2.3.1. Overview of Cocatalysts 4977 2.3.2. Reducing Agents 4977 2.3.3. Free Radical Initiators 4977 2.3.4. Metal Alkoxides 4977 2.3.5. Amines 4978 2.3.6. Halogen Source 4978 2.4. Initiators 4978 2.4.1. Overview of Initiators: Scope and Design 4978 2.4.2. Alkyl Halides 4978 2.4.3. Arenesulfonyl Halides 4979 2.4.4. N-Chloro Compounds 4979 2.4.5. Halogen-Free Initiators 4979 2.5. Solvents 4980 2.5.1. Overview of Solvents 4980 2.5.2. Catalyst Solubility and Coordination of Solvent 4981 2.5.3. Environmentally Friendly Solvents 4981 2.5.4. Water 4981 2.5.5. Catalytic Solvents: Catalyst Disproportionation 4981

Strategies for the Conversion of Lignin to High-Value Polymeric Materials: Review and Perspective

Abstract: The majority of commodity plastics and materials are derived from petroleum-based chemicals, illustrating the strong dependence on products derived from non-renewable energy sources. As the most accessible, renewable form of carbon (in comparison to CO2), lignocellulosic biomass (defined as organic matter available on a renewable basis) has been acknowledged as the most logical carbon-based feedstock for a variety of materials such as biofuels and chemicals. This Review focuses on methods developed to synthesize polymers derived from lignin, monolignols, and lignin-derived chemicals. Major topics include the structure and processing of lignocellulosic biomass to lignin, polymers utilizing lignin as a macromonomer, synthesis of monomers and polymers from monolignols, and polymers from lignin-derived chemicals, such as vanillin.