Details

Autor(en) / Beteiligte

• Ghose, Sayata
• Isayev, Avraam I.
• von Meerwall, Ernst

Titel

Effect of ultrasound on thermoset polyurethane: NMR relaxation and diffusion measurements

Ist Teil von

• Polymer (Guilford), 2004-05, Vol.45 (11), p.3709-3720

Ort / Verlag

Oxford: Elsevier Ltd

Erscheinungsjahr

2004

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Recycling of rubber-based materials is of increasing industrial environmental importance. In order to characterize the effect of ultrasound on polymer networks, nuclear magnetic resonance (NMR) relaxation and pulsed-gradient diffusion measurements were made at 70.5 °C in polyurethane rubber (PUR) and foam after subsequent treatment by intense ultrasound. The proton transverse relaxation decay was analyzed in terms of molecular and segmental mobilities of all motional species, a chemical and physical network as well as diffusing sol. The diffusivity spectrum, measurable in foams, reflected the changing molecular weight distribution of low-molecular weight sol and oligomers. It was observed that the effect of ultrasound was less pronounced in PUR than rubbers like SBR, PDMS and BR owing to its low degree of unsaturation. The investigation on the foams is the first of its kind to be reported.