TSU

 

 

 

  

 

 

PROJECT 00-500

 

 

 

New approaches to the studies of associating ionic polysaccharides in solution and at interface

 

 

 

July 1, 2001 June 30, 2004

 

 

 

Co-ordinator -  Professor M.Rinaudo

 

 

 

 

The main objective of the project is to understand the structure and nature of aggregates formed in aqueous solutions of industrially important ionic polysaccharides: chitosan and hydrophobically modified (HM) chitosan.

The work consists of several tasks:

1) to prepare a series of well characterized samples of HM chitosan with different content, chain length and degree of branching of hydrophobic alkyl side chains;

2) to study experimentally and theoretically the nature of aggregates in aqueous solutions of charged unmodified chitosan which seem to be a peculiar feature for many charged polysaccharides;

3) to study the self-association in aqueous solutions of HM chitosan with a particular attention to the search for finite size clusters recently predicted theoretically for any polyelectrolytes with associative groups;

4) to study the kinetics of adsorption of HM chitosan on air/water interface in order to develop a new chromatographic procedure, which allows one to fractionate the hydrophobically associating macromolecules according to their degree of hydrophobicity;

5) to investigate the self-association in the adsorption monolayers of HM chitosan submitted to a lateral compression with a particular attention to the role which is played by the interface in the formation of micelle-like aggregates.

 

These studies will permit to better understand a picture of various intermolecular interactions in associating ionic polysaccharides, which is important in the unfolding of numerous practical applications of these polymers.

 

 

 

 

 

Cooperation

 

 

 

 

Five research teams (two from INTAS members and three from Russia) with complementary expertise will be involved in the project. Different experimental techniques (small-angle X-ray and neutron scattering, static and dynamic light scattering, fluorescence spectroscopy, tensiometry, monolayer technique etc.) will be used. The experimental studies will be supported by theoretical investigations.

 

 

Professor

Marguerite Rinaudo

 

Centre de Recherches sur les Macromolecules Vegetales

Rue de la Chimie 601, BP 53

38041 Cedex 9 Grenoble

FRANCE

 

Professor

Kell Mortensen

Riso National Laboratory

Danish Polymer Centre

Polymer Science Laboratory

Frederiksborgvej 399

DK 4000 Roskilde

DENMARK

 

Professor

Alexei Khokhlov

Chair of Polymer and Crystal Physics

Physics Department

Moscow State University

Vorobyovy Gory, 117234 Moscow

RUSSIA

 

Professor

Yuri Monakov

Institute of Organic Chemistry

Ufa Research Center

Laboratory of Stereoregular Polymers

Prospekt Oktiabria 71, 450054 Ufa

RUSSIA

 

Professor

Valery Babak

 Institute of Organoelement Compounds of the RAS

Laboratory of Physicochemistry

of Interfacial Phenomena

Vavilova str., 28, 117813 Moscow

RUSSIA