La lignine, une molécule d'intérêt issue du bioraffinage

in Chimie Nouvelle (2012), 111

The implementation of lignocellulosic biorefinery initiatives generates significant amounts of underexploited lignins. Lignin, one of the most abundant renewable molecules on earth, is a highly branched ... [more ▼]

The implementation of lignocellulosic biorefinery initiatives generates significant amounts of underexploited lignins. Lignin, one of the most abundant renewable molecules on earth, is a highly branched biopolymer consisting of aromatic units. Generally intended for energy purposes, lignin has nowadays opened new vistas for higher added-value applications such as syngas, additive in the plastics industry or as a source of aromatic compounds dedicated to the chemical sector. This article provides an update on this molecule and its potential applications. [less ▲]

L'extrapolation des bioréacteurs : un problème de génie des procédés ou de physiologie microbienne ?

in Chimie Nouvelle (2010), 104

Bioreactor scale-up often pose a serious issue during the industrial development of a bioprocess considering the numerous physical and biological phenomena occurring in the reacting volume. The basic ... [more ▼]

Bioreactor scale-up often pose a serious issue during the industrial development of a bioprocess considering the numerous physical and biological phenomena occurring in the reacting volume. The basic principles of scale-up coming from the traditional chemical and process engineering approaches will be first reviewed and will be then compared to a new one involving recent development at the level of microbial strain manipulation. This "physiological" approach of scale-up involves directly a biological component of the system (by comparison with the traditional approach for scaling-up involving physical parameters indirectly linked to the physiological phenomena occurring in the bioreactor), i.e. the synthesis of a reporter fluorescent protein when microbial cells are exposed to stress. It will be shown how this principle can be used for a better understanding of the relationship between bioreactor hydrodynamics and microbial stress. [less ▲]

Amphiphilic and biodegradable copolymers for applications in vectorisation

in Chimie Nouvelle (2007), (94), 8-13

The development of controlled drug delivery systems is today a topic of an intense research activity. In this field, biocompatible and (bio)degradable polymers are particularly studied. The production of ... [more ▼]

The development of controlled drug delivery systems is today a topic of an intense research activity. In this field, biocompatible and (bio)degradable polymers are particularly studied. The production of nanosized particles (polymer micelles, nanoparticles,...) generally requires the elaboration of functional amphiphilic copolymers able to stabilize efficiently these colloidal dispersions. Various strategies to synthesize such copolymers keeping their (bio)degradability are described here. The complexity of these amphiphilic materials will be gradually increased in parallel to the improvement of the nanocarriers properties. [less ▲]

Controlled radical polymerization of vinyl acetate based on cobalt(II) acetyl acetonate

in Chimie Nouvelle (2005)

Controlled radical polymerization (CRP) is a valuable strategy to design a large range of polymers with well defined molecular characteristics under non very demanding conditions. However, the known CRP ... [more ▼]

Controlled radical polymerization (CRP) is a valuable strategy to design a large range of polymers with well defined molecular characteristics under non very demanding conditions. However, the known CRP techniques, such as nitroxide mediated polymerization (NMP), atom transfer radical polymerization (ATRP) and radical addition-fragmentation chain transfer polymerization (RAFT), suffer from limitations, including a moderate control on the vinyl acetate polymerization. Within the search for new controlled radical polymerization processes, we designed a system based on the reversible combination of growing macroradicals with a cobalt(II)acetylacetonate complex which provides an effective control of the vinyl acetate polymerization even when carried out in suspension in water. In a macromolecular engineering effort, well-defined end-functional poly(vinyl acetate), and poly(vinyl acetate) or poly(vinyl alcohol) containing block copolymers have been synthesized. [less ▲]

Des matériaux CMI-n aux matériaux macro-mésoporeux hiérarchisés: Evolution vers la notion de "One-pot reactor"

in Chimie Nouvelle (2005), 89

Les ingénieurs chimistes et leurs instruments: Le cas de l'analyse polarimétrique dans l'industrie sucrière

in Chimie Nouvelle (1999), 17(68), 3008-3011

This article put forward the complexe relations that exists between chemists ingeneers and the development of the Sugar industry in Belgium (in the 19s century). The argument is that the technical ... [more ▼]

This article put forward the complexe relations that exists between chemists ingeneers and the development of the Sugar industry in Belgium (in the 19s century). The argument is that the technical dimension of the implementation of a new chemical protocol for the delivery of sugar beets may be of some importance in order to understand the sociological dimension of contractual relations between actors and the role of scientific expertise in such a context. [less ▲]

Psychrophiles et thermophiles : un problème d’enzyme

in Chimie Nouvelle (1997), 15