Molecular self-assembly is the spontaneous association of molecules under equilibrium conditions into stable, structurally well-defined aggregates joined by noncovalent bonds. Molecular self-assembly is ubiquitous in biological systems and underlies the formation of a wide variety of complex biological structures. Understanding self-assembly and the associated noncovalent interactions that connect complementary interacting molecular surfaces in biological aggregates is a central concern in structural biochemistry. Self-assembly is also emerging as a new strategy in chemical synthesis, with the potential of generating nonbiological structures with dimensions of 1 to 10(2) nanometers (with molecular weights of 10(4) to 10(10) daltons). Structures in the upper part of this range of sizes are presently inaccessible through chemical synthesis, and the ability to prepare them would open a route to structures comparable in size (and perhaps complementary in function) to those that can be prepared by microlithography and other techniques of microfabrication.

Molecular self-assembly and nanochemistry: A chemical strategy for the synthesis of nanostructures

Renewable resources are used increasingly in the production of polymers. In particular, monomers such as carbon dioxide, terpenes, vegetable oils and carbohydrates can be used as feedstocks for the manufacture of a variety of sustainable materials and products, including elastomers, plastics, hydrogels, flexible electronics, resins, engineering polymers and composites. Efficient catalysis is required to produce monomers, to facilitate selective polymerizations and to enable recycling or upcycling of waste materials. There are opportunities to use such sustainable polymers in both high-value areas and in basic applications such as packaging. Life-cycle assessment can be used to quantify the environmental benefits of sustainable polymers.

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Sustainable polymers from renewable resources

Chemical modification of lignins: Towards biobased polymers

Synthesis, properties, and applications of magnetic iron oxide nanoparticles

A review on pyrolysis of plastic wastes

Thermal behavior of biodegraded lime wood.

pH-Sensitive hydrogels of 2-hydroxyethyl methacrylate/citraconic anhydride–modified collagen were obtained by free radical copolymerization/crosslinking in the presence of ammonium persulfate/N,N,N...

pH-Responsive 2-hydroxyethyl methacrylate/citraconic anhydride–modified collagen hydrogels as ciprofloxacin carriers for wound dressings:

The enzymatic degradation of poly(N-isopropyl acrylamide) (PNIPAM) grafted to carboxymethylcellulose (CMC) copolymers with a cellulasic preparation (Trichoderma viride) was studied. The enzymatic activity of the cellulasic preparation against CMC and the grafted copolymers was determined by the Petterson–Porath method, while their reduced viscosity variation in the presence of the same preparation was also followed. It has been shown that the enzymatic degradation behavior depends on the copolymer composition and the reaction temperature. Reducing sugars analysis showed that the experimental values for the grafted copolymers were higher than the calculated ones. At 50°C, the enzymatic reaction is completed in about 20 min for the copolymers, whereas for CMC it takes more than 40 min. It can be concluded that their enzymatic degradation is facilitated by the presence of the PNIPAM grafts. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1383–1386, 2003

Enzymatic degradation of thermoresponsive poly(N‐isopropylacrylamide) grafted to carboxymethylcellulose copolymers

Ont ete obtenus des melanges constitues par des polyolefines/lignosulfonates. Dans ce but, ont ete utilises deux procedes : la modification chimique de la lignine et l'incorporation des agents de compatibilisation. Quelques melanges presentent une vitesse satisfainte de biodegradation. A partir des etudes de la compatibilite de ces melanges et du comportement dans les tests de biodegradation, ont ete etablies des rapports optimes de la compatibilite et la quantite minime de lignine qui assure la desintegration/biodegradation des materiaux, designes comme des produits avec une vie medium de service. Par cette procedure, a ete develope un nouveau moyen pour la recuperation superieure de la lignine, comme dechet dans l'industrie du papier.

Cornelia Vasile

Papers

Thermal behavior of biodegraded lime wood.

pH-Responsive 2-hydroxyethyl methacrylate/citraconic anhydride–modified collagen hydrogels as ciprofloxacin carriers for wound dressings:

Enzymatic degradation of thermoresponsive poly(N‐isopropylacrylamide) grafted to carboxymethylcellulose copolymers

Polyolefins/lignosulfonates blends

Thermal behavior of some wood species treated with ionic liquid