Effect of PEO/PPO type triblock copolymers on dispersion behaviour of aqueous alumina suspensions

Şakar A. M., Polat H., Çiftçioǧlu M.

7th Conference of the European Ceramic Society, Brugge, Belçika, 9 - 13 Eylül 2001, cilt.206-213, ss.421-424, (Tam Metin Bildiri) identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Cilt numarası: 206-213
  • Basıldığı Şehir: Brugge
  • Basıldığı Ülke: Belçika
  • Sayfa Sayıları: ss.421-424
  • Anahtar Kelimeler: Alumina, Dispersion, Stabilization and block copolymers
  • Manisa Celal Bayar Üniversitesi Adresli: Hayır

Özet

The aim of this study was to investigate the stability and dispersion behaviour of aqueous alumina suspensions in the presence of polyethylene oxide-polypropylene oxide-polyethylene oxide (PEO/PPO/PEO) type block copolymers. The influence of water soluble triblock copolymers with molecular weight ranging from 2900 to 12600 g/mole were tested at Φ = 0.125, 1, 10, 20 vol % solid loading alumina suspensions by rheological, turbidity, sedimentation and surface tension measurements. The results indicate that an alternative dispersant for alumina suspensions is the PEO/PPO triblock copolymers. Their stabilisation mechanism was attributed to the depletion stabilisation. Rheological measurements indicated that these block copolymers (at high EO percentages) coupled with ultrasonic treatment have a positive effect on the dispersion of the agglomerated alumina suspensions. It was not possible to create stable dispersions in the absence of ultrasonic bath treatment. Turbidity measurements at Φ = 0.025, 0.125 vol % showed that, alumina suspensions with PEO/PPO added were stable and have higher turbidity values than block copolymer free suspensions.