6533b7d8fe1ef96bd126afb9

RESEARCH PRODUCT

Guar gum/borax hydrogel: Rheological, low field NMR and release characterizations

G. TeseiMario GrassiGesmi MilcovichFranco AlhaiqueRossella FarraPietro MatricardiSimona Maria FiorentinoTommasina CovielloFioretta Asaro

subject

Low field NMRMaterials sciencePolymers and PlasticsField (physics)General Chemical EngineeringDiffusionTransport processeslcsh:Chemical technologyPolymer Gels; Rheology; Low Field NMR; Transport processes; Mesh-sizechemistry.chemical_compoundRheologylcsh:TA401-492Materials ChemistryPolymer Gellcsh:TP1-1185Physical and Theoretical ChemistryComposite materialTransport processeGuar gumBoraxPolymer gelsOrganic ChemistryMesh-sizeLow field nuclear magnetic resonanceLow Field NMRlow field nmr; mesh-size; polymer gels; rheology; transport processesChemical engineeringchemistrySettore CHIM/09 - Farmaceutico Tecnologico ApplicativoSelf-healing hydrogelsViscous effectlcsh:Materials of engineering and construction. Mechanics of materialsRheology

description

Guar gum (GG) and Guar gum/borax (GGb) hydrogels are studied by means of rheology, Low Field Nuclear Magnetic Resonance (LF NMR) and model drug release tests. These three approaches are used to estimate the mesh size (ζ) of the polymeric network. A comparison with similar Scleroglucan systems is carried out. In the case of GGb, the rheological and Low Field NMR estimations of ζ lead to comparable results, while the drug release approach seems to underestimate ζ. Such discrepancy is attributed to the viscous effect of some polymeric chains that, although bound to the network to one end, can freely fluctuate among meshes. The viscous drag exerted by these chains slows down drug diffusion through the polymeric network. A proof for this hypothesis is given by the case of Scleroglucan gel, where the viscous contribution is not so significant and a good agreement between the rheological and release test approaches was found.

yearjournalcountryeditionlanguage
2013-09-01Express Polymer Letters
https://doi.org/10.3144/expresspolymlett.2013.71