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Titolo:
High temperature lifetime of polyimide/poly(silsesquioxane)-like hybrid films
Autore:
Tsai, MH; Whang, WT;
Indirizzi:
Natl Chiao Tung Univ, Dept Mat Sci & Engn, Hsinchu 30049, Taiwan Natl Chiao Tung Univ Hsinchu Taiwan 30049 & Engn, Hsinchu 30049, Taiwan
Titolo Testata:
JOURNAL OF POLYMER RESEARCH-TAIWAN
fascicolo: 2, volume: 8, anno: 2001,
pagine: 77 - 89
SICI:
1022-9760(200106)8:2<77:HTLOPH>2.0.ZU;2-G
Fonte:
ISI
Lingua:
ENG
Soggetto:
SOL-GEL PROCESS; LOW-DIELECTRIC-CONSTANT; VAPOR-DEPOSITION POLYMERIZATION; RELATIVE PERMITTIVITY; POLYIMIDE FILMS; SILICA; POLY(SILSESQUIOXANE); ALKOXYSILANE; COMPOSITES; RELAXATION;
Keywords:
polyimide/poly(silsesquioxane)-like decomposition activation energy; master curve; WLF equation; dynamic relaxation modulus; lifetime;
Tipo documento:
Article
Natura:
Periodico
Settore Disciplinare:
Physical, Chemical & Earth Sciences
Citazioni:
42
Recensione:
Indirizzi per estratti:
Indirizzo: Whang, WT Natl Chiao Tung Univ, Dept Mat Sci & Engn, Hsinchu 30049, TaiwanNatl Chiao Tung Univ Hsinchu Taiwan 30049 sinchu 30049, Taiwan
Citazione:
M.H. Tsai e W.T. Whang, "High temperature lifetime of polyimide/poly(silsesquioxane)-like hybrid films", J POLYM R, 8(2), 2001, pp. 77-89

Abstract

Decomposition kinetics in thermogravimetric analysis (TGA) and dynamic mechanical relaxation in dynamic mechanical analysis (DMA) are used to study the high temperature lifetime of the new type of polyimide/poly(silsesquioxane)-like (PI/PSSQ-like) hybrid films, which are designed to form three-dimensional structures with linear polyimide blocks and a crosslinked PSSQ-likestructure. Both TGA and DMA analysis reveal that the PI/PSSQ-like hybrid films have a longer lifetime (are more reliable) with regard to their thermal and mechanical characteristics than that of pure PI. Even just 2 wt% of p-aminophenyltrimethoxysilane (APTS) in a PI/PSSQ-like hybrid film can significantly improve the service lifetime by as much as at least four times in a TGA decomposition kinetic study. The dynamical relaxation data are well fitted to the calculated WLF (Williams-Landel-Ferry) master curves. In a series of X-PIS (PI modified with APTS) hybrid films, decreasing the PI block chain length increases the decomposition activation energy, lifetime (in both TGA and DMA) and relaxation modulus. In a series of X-PIS-y-PTS [PI modified with APTS and phenyltrimethoxysilane (PTS)] films, the decomposition activation energy and lifetime (in TGA) increase with the PTS content. Interestingly, the dynamic mechanical relaxation modulus of 10000-PIS-100-PTS film is lower than that of the corresponding 10000-PIS film at frequency > 10(2) rad/sec, but higher at frequency < 10(2) rad/sec. The 10000-PIS-100-PTShas a lower relaxation time than the 10000-PIS at the modulus 5x10(8) Pa, but the relaxation time of the former becomes higher at 5x10(7) Pa.

ASDD Area Sistemi Dipartimentali e Documentali, Università di Bologna, Catalogo delle riviste ed altri periodici
Documento generato il 08/07/20 alle ore 07:40:58