Advanced

Nanoscopic properties of silica filled polydimethylsiloxane by means of positron annihilation lifetime spectroscopy

Winberg, Petra LU ; Eldrup, Morten LU and Maurer, Frans LU (2004) In Polymer 45(24). p.8253-8264
Abstract
Positron annihilation lifetime spectroscopy (PALS) was performed on a series of polydimethylsiloxane (PDMS)/fumed silicon dioxide (SiO2) composites at temperatures between -185 and 100degreesC to study the effect of filler content and filler particle size on the free volume properties and the positron annihilation characteristics. The glass transition behavior of the PDMS/SiO2 composites was determined with differential scanning calorimetry. A clear influence on the o-Ps lifetime (73) in the polymer upon addition of nano-sized fumed SiO2 was observed at all temperatures. The observed o-Ps lifetime behavior was related to filler content and filler particle size. A transition in the temperature dependence of the o-Ps lifetime was observed... (More)
Positron annihilation lifetime spectroscopy (PALS) was performed on a series of polydimethylsiloxane (PDMS)/fumed silicon dioxide (SiO2) composites at temperatures between -185 and 100degreesC to study the effect of filler content and filler particle size on the free volume properties and the positron annihilation characteristics. The glass transition behavior of the PDMS/SiO2 composites was determined with differential scanning calorimetry. A clear influence on the o-Ps lifetime (73) in the polymer upon addition of nano-sized fumed SiO2 was observed at all temperatures. The observed o-Ps lifetime behavior was related to filler content and filler particle size. A transition in the temperature dependence of the o-Ps lifetime was observed close to -35degreesC above which temperature PDMS exhibits long o-Ps lifetimes. A relationship between tau(3) and the surface tension, equivalent to the behavior of ordinary molecular liquids was observed in this temperature region. The o-Ps yield was strongly reduced in the crystallization region and by addition Of SiO2. The reduction due to filler addition did, however, in the case of nano-sized SiO2 not follow a linear relationship with filler weight, which was observed for micron-sized fillers. The nonlinear relationship between filler weight and o-Ps yield could be due to out-diffusion of positrons and/or o-Ps from the filler particles to the matrix. (C) 2004 Elsevier Ltd. All rights reserved. (Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Polymer
volume
45
issue
24
pages
8253 - 8264
publisher
Elsevier
external identifiers
  • wos:000225119600019
  • scopus:7644224286
ISSN
0032-3861
DOI
10.1016/j.polymer.2004.09.080
language
English
LU publication?
yes
id
047cf34c-cc67-4593-aae5-abda6aebdf76 (old id 139477)
date added to LUP
2007-07-13 16:47:11
date last changed
2017-11-19 04:15:53
@article{047cf34c-cc67-4593-aae5-abda6aebdf76,
  abstract     = {Positron annihilation lifetime spectroscopy (PALS) was performed on a series of polydimethylsiloxane (PDMS)/fumed silicon dioxide (SiO2) composites at temperatures between -185 and 100degreesC to study the effect of filler content and filler particle size on the free volume properties and the positron annihilation characteristics. The glass transition behavior of the PDMS/SiO2 composites was determined with differential scanning calorimetry. A clear influence on the o-Ps lifetime (73) in the polymer upon addition of nano-sized fumed SiO2 was observed at all temperatures. The observed o-Ps lifetime behavior was related to filler content and filler particle size. A transition in the temperature dependence of the o-Ps lifetime was observed close to -35degreesC above which temperature PDMS exhibits long o-Ps lifetimes. A relationship between tau(3) and the surface tension, equivalent to the behavior of ordinary molecular liquids was observed in this temperature region. The o-Ps yield was strongly reduced in the crystallization region and by addition Of SiO2. The reduction due to filler addition did, however, in the case of nano-sized SiO2 not follow a linear relationship with filler weight, which was observed for micron-sized fillers. The nonlinear relationship between filler weight and o-Ps yield could be due to out-diffusion of positrons and/or o-Ps from the filler particles to the matrix. (C) 2004 Elsevier Ltd. All rights reserved.},
  author       = {Winberg, Petra and Eldrup, Morten and Maurer, Frans},
  issn         = {0032-3861},
  language     = {eng},
  number       = {24},
  pages        = {8253--8264},
  publisher    = {Elsevier},
  series       = {Polymer},
  title        = {Nanoscopic properties of silica filled polydimethylsiloxane by means of positron annihilation lifetime spectroscopy},
  url          = {http://dx.doi.org/10.1016/j.polymer.2004.09.080},
  volume       = {45},
  year         = {2004},
}