Free volume and swelling in thin films of poly(N-isopropylacrylamide) end-capped with N-butyltrithiocarbonate

S. Harms, K. Rätzke, F. Faupel, W. Egger, L. Ravello, A. Laschewsky, W. Wang, P. Müller-Buschbaum

Research output: Contribution to journalArticlepeer-review

21 Scopus citations

Abstract

The free volume in thin films of poly(N-isopropylacrylamid) end-capped with n-butyltriocarbonate (nbc-PNIPAM) is probed with positron annihilation lifetime spectroscopy (PALS). The PALS measurements are performed as function of energy to obtain depth profiles of the free volume of nbc-PNIPAM films. The range of nbc-PNIPAM films with thicknesses from 40 to 200 nm is focused. With decreasing film thickness the free volume increases in good agreement with an increase in the maximum swelling capability of the nbc-PNIPAM films. Thus in thin hydrogel films the sorption and swelling behavior is governed by free volume. (Figure Presented)

Original languageEnglish
Pages (from-to)1364-1367
Number of pages4
JournalMacromolecular Rapid Communications
Volume31
Issue number15
DOIs
StatePublished - 3 Aug 2010

Keywords

  • Block copolymers
  • Films
  • Free volume
  • Positron annihilation
  • Stimuli-sensitive polymers
  • Swelling hydrogel films

Fingerprint

Dive into the research topics of 'Free volume and swelling in thin films of poly(N-isopropylacrylamide) end-capped with N-butyltrithiocarbonate'. Together they form a unique fingerprint.

Cite this