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Titolo:
Photopolymerization behavior of di(meth)acrylate oligomers
Autore:
Yu, Q; Nauman, S; Santerre, JP; Zhu, S;
Indirizzi:
McMaster Univ, Dept Chem Engn, Hamilton, ON L8S 4L7, Canada McMaster UnivHamilton ON Canada L8S 4L7 gn, Hamilton, ON L8S 4L7, Canada Bloorview MacMillan Ctr, Rehabil Engn Dept, Toronto, ON M4G 1R8, Canada Bloorview MacMillan Ctr Toronto ON Canada M4G 1R8 nto, ON M4G 1R8, Canada Univ Toronto, Fac Dent, Toronto, ON M5G 1G6, Canada Univ Toronto Toronto ON Canada M5G 1G6 Dent, Toronto, ON M5G 1G6, Canada
Titolo Testata:
JOURNAL OF MATERIALS SCIENCE
fascicolo: 15, volume: 36, anno: 2001,
pagine: 3599 - 3605
SICI:
0022-2461(2001)36:15<3599:PBODO>2.0.ZU;2-W
Fonte:
ISI
Lingua:
ENG
Soggetto:
PHOTOINITIATED POLYMERIZATION; LIGHT-INTENSITY; KINETICS; DIMETHACRYLATES; TEMPERATURE;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Engineering, Computing & Technology
--discip_EC--
Citazioni:
21
Recensione:
Indirizzi per estratti:
Indirizzo: Zhu, S McMaster Univ, Dept Chem Engn, Hamilton, ON L8S 4L7, Canada McMaster Univ Hamilton ON Canada L8S 4L7 ilton, ON L8S 4L7, Canada
Citazione:
Q. Yu et al., "Photopolymerization behavior of di(meth)acrylate oligomers", J MATER SCI, 36(15), 2001, pp. 3599-3605

Abstract

Photo-initiated polymerizations of two series of di(meth)acrylate oligomers, one bisphenol-A based and the other ethylene glycol based, with a camphorquinone/tertiary amine radical photo-initiator system were studied using differential scanning calorimetry. Bisphenol-A based oligomers polymerized much faster than ethylene glycol based oligomers because the higher viscosity of E-bis-A oligomers induced an autoacceleration upon exposure to ultraviolet (UV) radiation; however, higher vinyl conversions were observed with ethylene glycol oligomers due to their greater segmental mobility and elastomeric character of the cured networks. The two series also showed very different temperature dependence for vinyl group conversion. The polymerizationrate of E-bis-A DMA oligomers increased when the number of oxyethyl units increased from four to six, but the rate decreased when the spacer length further increased. The exponential factors of the rate dependence on the CQ concentration for all the oligomers were smaller than 0.5. Below 70 degreesC, the maximum rate of polymerization increased with temperature, and yielded apparent activation energies between 10.3-11.6kJ/mol. At temperatures greater than or equal to 80 degreesC, the reduced viscosity and improved segmental mobility suppressed autoacceleration, causing the maximum rate to decrease with an increase of temperature. (C) 2001 Kluwer Academic Publishers.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 30/11/20 alle ore 16:43:05