Kinetics of Gelation

The HM and LM pectins give two very different types of gels the mechanisms of stabilization of the junction zones in the two cases are described and few characteristics given. The different molecular characteristics (DE, distribution of methoxyl or acetyl substituents, neutral sugar content or rhamnose content) play an important role on the kinetic of gelation, mechanical properties of the gel formed and also on the experimental conditions to form the stronger gels. All these points were briefly discussed. 

Kinetics of Gelation Studied by Dynamic Rheological Measurements... 

All models described up to here belong to the class of equilibrium theories. They have the advantage of providing structural information on the material during the liquid-solid transition. Kinetic theories based on Smoluchowski s coagulation equation [45] have recently been applied more and more to describe the kinetics of gelation. The Smoluchowski equation describes the time evolution of the cluster size distribution N(k) ... 

When the helix amount increases the medium changes from a viscous liquid (sol) to an elastic solid (gel). The kinetics of gelation depends strongly on the quenching temperature. The rheological measurements that we performed are particularly focused on the sol-gel transition and on the definition of the "gel point". The greatest difficulty encountered is due to the weakness of the bonds which can easily be destroyed by the mechanical stress. 

The results of rheological investigation of the kinetics of gelation of physical nature, taking place as a result of phase sepiuation of the corresponding polymer... 

Kalnin, I. Hollands, K. Kinetics of gelation of some accelerated acid anhydride cured epoxy resins. In Epoxy Resins ACS Washington, DC, 1970. 

Cellulose aerogels are at the beginning of intensive research and owing to their fascinating structure and properties they promise to have many applications. Various routes have been tested to produce aerogels. There is ample space for improvement and refinement as well as fundamental research on the kinetics of gelation in a solution of the flexible... 

Djabourov M.,J. Maquet, H. Theveneau, J. Leblond and P. Papon, Kinetics of gelation of aqueous gelatin solutions, Br. Polym. J., 17 (1985) 169-174. 

As determined in Sect. 4.2.3, the temperatnre d affects the kinetic of gelation. Additionally, temperature d also influences the size of the primary particles [20]. The nsage of a thermostated tank reactor (see Fig. 8) with stirring speed Hs = 400min is appropriate to account for both effects under influence of stirring. See Table 1 for the composition of the reactants, heated up to experimental temperatnre. 

Felix L, Hernandez J, Arguelles-Monal WM et al (2005) Kinetics of gelation and thermal sensitivity of N-isobutyryl chitosan hydrogels. Biomacromolecules 6 2408-2415 Zhang J, Chen XG, Li YY et al (2007) Self-assembled nanoparticles based on hydrophobi-cally modified chitosan as carriers for doxorubicin. Nanomed Nanotechnol 3 258-265 Tong YJ, Wang SF, Xu JW et al (2005) Synthesis of O, O -dipahnitoyl chitosan and its amphiphilic properties and capability of cholesterol absorption. Carbohyd Poiym 60 229-233... 

Felix, L Hernandez, J Arguelles-Monal, WM Goycoolea, FM. Kinetics of Gelation and Thermal Sensitivity of N-Isobutyryl Chitosan Hydrogels. Biomacromolecules, 2005, 6, 2408-2415. 

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