Polyol-assisted vermiculite dispersion in polyurethane nanocomposites

Yong Tae Park, Yuqiang Qian, Chris I. Lindsay, Conny Nijs, Rafael E. Camargo, Andreas Stein, Christopher W. Macosko

Research output: Contribution to journalArticlepeer-review

28 Scopus citations

Abstract

The largest use of polyurethane (PU) is as closed cell rigid foams for thermal insulation. One problem is loss of blowing gases, which leads to slow increase in thermal conductivity. PU composites with plate-like nanofillers create a diffusion barrier, reducing gas transport and slowing insulation aging. In this research, a new in situ intercalative polymerization is described to disperse vermiculite (VMT) in PU. When VMT was modified by cation exchange with long-chain quaternary ammonium, the dispersion in methylene diphenyl diisocyanate (MDI) was significantly improved. Dispersion of clay in MDI was further improved by combining high intensity dispersive mixing with a polyol-clay preblend (master-batch). The VMT dispersibility was characterized using rheology, microscopy, and X-ray scattering/diffraction. With the method of polyol-assisted VMT dispersion, electron microscopy revealed extensive intercalation and exfoliation of clay particles. In contrast, simple mixing of organoclay in MDI resulted in macroscopic localization and poor distribution of clay particles in PU. The final nanocomposites prepared by the master-batch method showed enhancement of mechanical properties (85% increase in elastic modulus) and reduction in permeability to CO2, as much as 40%, at a low clay concentration of 3.3 wt %.

Original languageEnglish (US)
Pages (from-to)3054-3062
Number of pages9
JournalACS Applied Materials and Interfaces
Volume5
Issue number8
DOIs
StatePublished - Apr 24 2013

Keywords

  • gas barrier
  • organoclay
  • polymer-clay nanocomposite
  • polyurethane
  • vermiculite

Fingerprint Dive into the research topics of 'Polyol-assisted vermiculite dispersion in polyurethane nanocomposites'. Together they form a unique fingerprint.

Cite this