Details

Autor(en) / Beteiligte

• Nigro, Valentina
• Angelini, Roberta
• Bertoldo, Monica
• Castelvetro, Valter
• Ruocco, Giancarlo
• Ruzicka, Barbara

Titel

Dynamic light scattering study of temperature and pH sensitive colloidal microgels

Ist Teil von

• Journal of non-crystalline solids, 2015-01, Vol.407, p.361-366

Ort / Verlag

Elsevier B.V

Erscheinungsjahr

2015

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Microgel particles composed of Interpenetrated Polymer Network (IPN) of poly(N-isopropylacrylamide) (PNIPAM) and poly(acrylic acid) (PAAc) dispersed in water have been investigated through dynamic light scattering. The study of the temperature, concentration and pH dependence of the relaxation time has highlighted the existence of a thermoreversible transition corresponding to the swollen–shrunken volume phase transition. The presence of PAAc introduces an additional pH-sensitivity with respect to the temperature-sensitivity due to PNIPAM and leads to interesting differences in the transition process at acid and neutral pH. •We characterize aqueous dispersions of IPN microgels of PNIPAM and PAAc.•The temperature, concentration and pH dependence of the relaxation time are investigated.•An evident transition from a swollen to a shrunken state is observed.•The presence of PAAc widely affects the relaxation time behavior.•The relaxation time behavior as a function of the momentum transfer is provided.