Reversible film formation from nano-sized PNIPAM particles below glass transition

Creative Commons License

Uğur Ş., Elaissari A., Yargı Ö., Pekcan M. Ö.

COLLOID AND POLYMER SCIENCE, vol.285, pp.423-430, 2007 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 285
  • Publication Date: 2007
  • Doi Number: 10.1007/s00396-006-1584-6
  • Journal Name: COLLOID AND POLYMER SCIENCE
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.423-430
  • Keywords: film formation, nanoparticles, poly (N-isopropylacrylamide), microgels, N-ISOPROPYLACRYLAMIDE GELS, VOLUME PHASE-TRANSITION, T LATEX-PARTICLES, PHOTON TRANSMISSION, MOLECULAR-WEIGHT, POLY(N-ISOPROPYLACRYLAMIDE) MICROGELS, ENERGY-TRANSFER, POLYSTYRENE, DISPERSION, FRACTURE
  • Yıldız Technical University Affiliated: Yes

Abstract

Reversible film formation process from nano-sized Poly(N-isopropylacrylamide) (PNIPAM) microgel particles were studied during heating-cooling cycles at various rates. Photon transmission technique was used and transmitted photon intensity I (tr) was monitored during heating-cooling cycles. The increase and decrease in I (tr) during heating and cooling was explained with the void closure and void reconstruction processes, and the corresponding activation energies were measured. It was observed that PNIPAM microgels required less energy during reconstruction of voids than their closure.