CORE
🇺🇦
make metadata, not war
Services
Services overview
Explore all CORE services
Access to raw data
API
Dataset
FastSync
Content discovery
Recommender
Discovery
OAI identifiers
OAI Resolver
Managing content
Dashboard
Bespoke contracts
Consultancy services
Support us
Support us
Membership
Sponsorship
Community governance
Advisory Board
Board of supporters
Research network
About
About us
Our mission
Team
Blog
FAQs
Contact us
Real time dielectric monitoring of glass transition in n-vinyl pyrrolidone polymerization
Authors
Arbuzov A.
Bayrak I.
Nigmatullin R.
Salehli F.
Publication date
1 January 2007
Publisher
Abstract
Real time dielectric spectroscopy was used for monitoring the dynamics during liquid glass transition in radical bulk polymerization of n-vinyl pyrrolidone. Two different relaxation mechanisms were identified. Initially segmental α-relaxation was dominant. Subsequently, contribution from slower motions became more significant and ε′(tr, ω) underwent maxima in all frequency bands up to 10 MHz. Peak amplitude increased and the occurring time was delayed with decreasing frequency. The slow region dynamics were similar to the dynamics of Chamberlin's domain-like model of glass transition. The glassy phase is formed by a segmental relaxation and a relaxation due to glassy regions. The characteristic relaxation times of slow and segmental motions were well described by a modified Vogel-Fulcher-Tammann relation. The high frequency behavior, associated with the segmental motions, is well described by Havriliak-Negami and Kohlrausch-Williams-Watts formulas, which did not provide satisfactory fittings for the dynamics of slow regions. Both real and imaginary parts of the dielectric data were fully described by a complex dielectric relaxation function, the parameters of which are found by the eigen-coordinates (EC) method. © 2007 Elsevier B.V. All rights reserved
Similar works
Full text
Open in the Core reader
Download PDF
Available Versions
Kazan Federal University Digital Repository
See this paper in CORE
Go to the repository landing page
Download from data provider
oai:dspace.kpfu.ru:net/136405
Last time updated on 07/05/2019