Search results for "SS-NMR"
showing 2 items of 2 documents
Study of the Curing Process of DGEBA Epoxy Resin Through Structural Investigation
2015
In this work, a multi-scale approach with different analytical methods is applied to study the curing process and the structural properties of a diglycidyl ether of bisphenol A (DGEBA) epoxy resin. This monomer, thermally cured using 4,4′-diaminodiphenilsulfone (DDS) as hardener, is analyzed after 10, 45, 90, and 120 min of reaction time at 180 °C to obtain information on samples with different cross-linking densities. Samples are also characterized after extraction in acetone in order to obtain structural information on the insoluble parts. For this purpose, differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), solid-state nuclear magnetic resonance (ss-NMR),…
La spettroscopia di risonanza magnetica nucleare in stato solido per lo studio dello stato di conservazione di materiali cellulosici
2013
This work shows the potentiality of the solid state nuclear magnetic resonance (ss-NMR) technique applied to characterize cellulosic materials and the possibility of analyze small amounts of starting material within reasonable experimental time using a modern equipment. The NMR analyses were performed to assess the conservation state of a material in order to plan appropriate conservative and restorative interventions. 13C {1H} Cross Polarization (CP) Magic Angle Spinning (MAS) NMR was used to identify the paper and wood components and the crystalline degree of the cellulose. Besides, in wood holocellulose/lignin ratio and the condensation degree of the lignin were determined.