Hyperbranched Polymers in Cationic Photopolymerization of Epoxy Systems
(2003) In Polymer Engineering and Science 43(8). p.1460-1465- Abstract
Mixtures of epoxy resins in the presence of epoxy hyperbranched polymers (HBP), in the range of 5-15 wt%, were investigated in the cationic photocuring process. No significant differences in rate of polymerization or final epoxy groups conversion were observed. At low concentration, HBP acts as plasticizer and causes a decrease of the glass transition temperature of the epoxy matrix and of the E' value. At higher concentration (about 15 wt%), two Tg values are evident, indicating a biphasic structure of the system. The SEM analysis of the fracture surface of the samples confirms a particulate structure with separate HBP domains interconnected to the epoxy matrix. In all the samples investigated, a clear increase of the impact... (More)
Mixtures of epoxy resins in the presence of epoxy hyperbranched polymers (HBP), in the range of 5-15 wt%, were investigated in the cationic photocuring process. No significant differences in rate of polymerization or final epoxy groups conversion were observed. At low concentration, HBP acts as plasticizer and causes a decrease of the glass transition temperature of the epoxy matrix and of the E' value. At higher concentration (about 15 wt%), two Tg values are evident, indicating a biphasic structure of the system. The SEM analysis of the fracture surface of the samples confirms a particulate structure with separate HBP domains interconnected to the epoxy matrix. In all the samples investigated, a clear increase of the impact resistance was observed, resulting either from the plasticization effect or from the particulate structure induced by the presence of the HBP resin.
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- author
- Sangermano, M. ; Malucelli, G. ; Bongiovanni, R. ; Priola, A. ; Harden, A. and Rehnberg, N. LU
- publishing date
- 2003-08
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Polymer Engineering and Science
- volume
- 43
- issue
- 8
- pages
- 6 pages
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- scopus:1542502817
- ISSN
- 0032-3888
- DOI
- 10.1002/pen.10123
- language
- English
- LU publication?
- no
- id
- 870443a1-4edc-4e78-aa76-30f63e47fc24
- date added to LUP
- 2021-11-25 11:32:53
- date last changed
- 2022-02-02 01:42:25
@article{870443a1-4edc-4e78-aa76-30f63e47fc24, abstract = {{<p>Mixtures of epoxy resins in the presence of epoxy hyperbranched polymers (HBP), in the range of 5-15 wt%, were investigated in the cationic photocuring process. No significant differences in rate of polymerization or final epoxy groups conversion were observed. At low concentration, HBP acts as plasticizer and causes a decrease of the glass transition temperature of the epoxy matrix and of the E' value. At higher concentration (about 15 wt%), two T<sub>g</sub> values are evident, indicating a biphasic structure of the system. The SEM analysis of the fracture surface of the samples confirms a particulate structure with separate HBP domains interconnected to the epoxy matrix. In all the samples investigated, a clear increase of the impact resistance was observed, resulting either from the plasticization effect or from the particulate structure induced by the presence of the HBP resin.</p>}}, author = {{Sangermano, M. and Malucelli, G. and Bongiovanni, R. and Priola, A. and Harden, A. and Rehnberg, N.}}, issn = {{0032-3888}}, language = {{eng}}, number = {{8}}, pages = {{1460--1465}}, publisher = {{John Wiley & Sons Inc.}}, series = {{Polymer Engineering and Science}}, title = {{Hyperbranched Polymers in Cationic Photopolymerization of Epoxy Systems}}, url = {{http://dx.doi.org/10.1002/pen.10123}}, doi = {{10.1002/pen.10123}}, volume = {{43}}, year = {{2003}}, }