Unexpected differences between thermal and photoinitiated cationic curing oa a diglycidyl ether of bisphenol. A modified with a multiarm star poly (styrene)-b-poly (e-caprolactone) polymer

View/Open
Cita com:
hdl:2117/19379
Document typeArticle
Defense date2013-03-18
Rights accessOpen Access
Except where otherwise noted, content on this work
is licensed under a Creative Commons license
:
Attribution-NonCommercial-NoDerivs 3.0 Spain
Abstract
The effect of adding a multiarm star poly(styrene)-b-poly("-caprolactone) polymer on the cationic thermal and
photoinitiated curing of diglycidyl ether of bisphenol A was studied. This star-polymer decelerated the thermal curing of
diglycidyl ether of bisphenol A and modified the final structure of the epoxy matrix. The photocuring was influenced significantly
by the addition of the multiarm star. When the proportion of this modifier added was 5%, much more time was
necessary for complete photocuring (160 min at 40ºC). In the presence of 10% of modifier, the degree of photocuring
reached was very low (0.196 at 120°C). A subsequent thermal post-curing was necessary to cure completely the system.
During photocuring in presence of poly(styrene)-b-poly("-caprolactone), the formation of dormant species, which are reactivated
when the temperature increases, takes places. The kinetics of the thermal curing and the photocuring was analyzed
using an isoconversional method due to the complexity of the reactive process. Applying this method, it has been confirmed
the dependence of activation energy on the degree of conversion. The fracture morphology analyzed by scanning electron
microscopy exhibited a second phase originated during photocuring by the presence of the modifier.
CitationMorancho, J. [et al.]. Unexpected differences between thermal and photoinitiated cationic curing oa a diglycidyl ether of bisphenol. A modified with a multiarm star poly (styrene)-b-poly (e-caprolactone) polymer. "Express polymer letters", 18 Març 2013, vol. 7, núm. 7, p. 565-576.
ISSN1788-618X
Publisher versionhttp://www.expresspolymlett.com
Files | Description | Size | Format | View |
---|---|---|---|---|
EPL-0004309_article.pdf | 629,6Kb | View/Open |