Characterization of free volume and density gradients of polystyrene surfaces by low-energy positron lifetime measurements
(2004) In Polymer 45(13). p.4533-4539- Abstract
- Free volume and density gradient widths of the free surface of high molecular mass polystyrene was characterized by use of a pulsed low-energy positron lifetime beam. A density gradient in terms of mass density (g/cm(3)) versus depth (nm) was obtained from the experimental beam data using a novel approach, yielding a width of the density gradient of approximately 3.5 nm. The procedure accounted for the broadening of the positron implantation probe as a function of energy as well as correcting for the increase in positron implantation depths due to the presence of a lower density at the surface region. Moreover, the spectra in the low implantation energy range were found to contain a long-lived lifetime that yielded very large estimates of... (More)
- Free volume and density gradient widths of the free surface of high molecular mass polystyrene was characterized by use of a pulsed low-energy positron lifetime beam. A density gradient in terms of mass density (g/cm(3)) versus depth (nm) was obtained from the experimental beam data using a novel approach, yielding a width of the density gradient of approximately 3.5 nm. The procedure accounted for the broadening of the positron implantation probe as a function of energy as well as correcting for the increase in positron implantation depths due to the presence of a lower density at the surface region. Moreover, the spectra in the low implantation energy range were found to contain a long-lived lifetime that yielded very large estimates of the free volume effects at the surface. Accounting for this lifetime in the evaluation procedure, resulted in a much improved agreement with the results of other experimental and theoretical investigations in the literature. (C) 2004 Elsevier Ltd. All rights reserved. (Less)
Please use this url to cite or link to this publication:
https://lup.lub.lu.se/record/139515
- author
- Algers, John LU ; Suzuki, R ; Ohdaira, T and Maurer, Frans LU
- organization
- publishing date
- 2004
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Polymer
- volume
- 45
- issue
- 13
- pages
- 4533 - 4539
- publisher
- Elsevier
- external identifiers
-
- wos:000221836600021
- scopus:2542478169
- ISSN
- 0032-3861
- DOI
- 10.1016/j.polymer.2004.04.008
- language
- English
- LU publication?
- yes
- additional info
- The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Polymer and Materials Chemistry (LTH) (011001041)
- id
- ca682eab-dd8f-4513-993a-f65e14dc6c71 (old id 139515)
- date added to LUP
- 2016-04-01 16:15:49
- date last changed
- 2022-01-28 18:28:34
@article{ca682eab-dd8f-4513-993a-f65e14dc6c71, abstract = {{Free volume and density gradient widths of the free surface of high molecular mass polystyrene was characterized by use of a pulsed low-energy positron lifetime beam. A density gradient in terms of mass density (g/cm(3)) versus depth (nm) was obtained from the experimental beam data using a novel approach, yielding a width of the density gradient of approximately 3.5 nm. The procedure accounted for the broadening of the positron implantation probe as a function of energy as well as correcting for the increase in positron implantation depths due to the presence of a lower density at the surface region. Moreover, the spectra in the low implantation energy range were found to contain a long-lived lifetime that yielded very large estimates of the free volume effects at the surface. Accounting for this lifetime in the evaluation procedure, resulted in a much improved agreement with the results of other experimental and theoretical investigations in the literature. (C) 2004 Elsevier Ltd. All rights reserved.}}, author = {{Algers, John and Suzuki, R and Ohdaira, T and Maurer, Frans}}, issn = {{0032-3861}}, language = {{eng}}, number = {{13}}, pages = {{4533--4539}}, publisher = {{Elsevier}}, series = {{Polymer}}, title = {{Characterization of free volume and density gradients of polystyrene surfaces by low-energy positron lifetime measurements}}, url = {{http://dx.doi.org/10.1016/j.polymer.2004.04.008}}, doi = {{10.1016/j.polymer.2004.04.008}}, volume = {{45}}, year = {{2004}}, }