Thermal expansion coefficients and moduli of uniaxially stretched polyimide films with rigid and flexible molecular chains

Numata, Shinichi; Miwa, Takao

doi:10.1016/0032-3861(89)90100-6

Cited by 56 publications

(31 citation statements)

References 9 publications

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“…Negative TECs were previously reported for some rigid polyimide films by Numata and Miwa 46 and Kim et al 29 Numata and Miwa 46 have prepared films of several polyimides, such as rigid poly(p-phenylene biphenyltetracarboximide) (BPDA-PDA) and semi-rigid poly(4,4Ј-oxydiphenylene pyromellitimide) (PMDA-ODA) and poly(4,4Ј-oxydiphenylene biphenyltetracarboximide) (BPDA-ODA), under stretching conditions. Before TEC measurements, the polyimide films were preheated up to the imidization temperature employed, in order to remove residual stress in the films.…”

Section: Thermal Expansivitymentioning

confidence: 84%

“…However, in the case of BPDA-PDA, its film prepared in a free-standing (that is, unstretched) condition shows a small positive TEC. 8,46 From these results, they have concluded that a polyimide with a high chain linearity and rigidity has a strong tendency to reveal a negative TEC in films prepared under stretching conditions and, however, a low TEC, even in films prepared without unstretching. Kim et al 29 have measured TECs of poly(p-phenylene pyromellitimide)s (PMDA-PDAs) with side groups such as methyl, methoxy, and trifluoromethyl in films prepared on substrates.…”

Section: Thermal Expansivitymentioning

confidence: 91%

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Synthesis and characterization of fully rodlike poly(4,4?-biphenylene pyromellitimide)s with various short side groups

Pyo

Kim

Shin

et al. 1999

J. Polym. Sci. A Polym. Chem.

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Section: Thermal Expansivitymentioning

confidence: 84%

Section: Thermal Expansivitymentioning

confidence: 91%

Synthesis and characterization of fully rodlike poly(4,4?-biphenylene pyromellitimide)s with various short side groups

Pyo

Kim

Shin

et al. 1999

J. Polym. Sci. A Polym. Chem.

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“…Although negative CTEs are often observed in highly uniaxially stretched samples (typically fibers) along the stretching direction, 31 it is very curious that 2,3,6,7-NTDA/TFMB film displayed a negative CTE (À3:2 ppm K À1 ) despite that the film was non-stretched. This unusual behavior is also observed in some limited systems, PMDA/TFMB and PMDA/m-tolidine (m-TOL).…”

Section: Film Properties Of 2367-ntda-derived Polyimidesmentioning

confidence: 99%

Low-CTE Polyimides Derived from 2,3,6,7-Naphthalenetetracarboxylic Dianhydride

Hasegawa

Horii

2007

Polym J

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ABSTRACT:2,3,6,7-naphthalenetetracarboxylic dianhydride (NTDA) showed high reactivity in the polymerization of polyimide precursors [poly(amic acid)s (PAAs)] with various aromatic and cycloaliphatic diamines with an exception of trans-1,4-cyclohexanediamine (CHDA). On the other hand, another isomer 1,4,5,8-NTDA did not allow the formation of high molecular weight PAAs. The poor reactivity of 1,4,5,8-NTDA is probably attributed to the more stable six-membered anhydride structure. The polyimide (PI) films derived from 2,3,6,7-NTDA with some diamines possessing stiff/linear structures, i.e., p-phenylenediamine (PDA), 4-aminophenyl-4 0 -aminobenzoate (APAB), and 2,2 0 -bis(trifluoromethyl)benzidine (TFMB) exhibited no distinct glass transitions on the dynamic mechanical thermal analysis or a considerably high T g exceeding 400 C, extremely low CTE values close to that of silicon wafer or lower, and relatively low degrees of water absorption simultaneously in addition to excellent thermal stability. A polyimide system derived from 2,3,6,7-NTDA and 4,4 0 -oxydianiline (4,4 0 -ODA) achieved a low CTE approximate to that of copper foil (20.0 ppm K À1 ) in spite of the presence of flexible ether linkages in the structure while retaining excellent film toughness (elongation at break > 80%). The low CTE characteristics observed probably results from the longer naphthaldiimide mesogenic unit which acts more effectively for the imidization-induced in-plane orientation. The properties of 2,3,6,7-NTDA-based PIs were compared with those of PIs derived from a fixed diamine with different dianhydrides, i.e., pyromellitic dianhydride (PMDA) and 3,3 0 ,4,4 0 -biphenyltetracarboxylic dianhydride (s-BPDA) to elucidate the merits of the use of 2,3,6,7-NTDA. The results revealed that 2,3,6,7-NTDA is a useful monomer for lowering both CTE and water absorption and enhancing T g . [doi:10.1295/polymj.PJ2006234] KEY WORDS Polyimides / 2,3,6,7-Naphthalenetetracarboxylic Dianhydride / 1,4,5,8-Naphthalenetetracarboxylic Dianhydride / Low Linear Coefficient of Thermal Expansion (CTE) / Low Water Absorption / Polyimides (PIs) have been widely utilized in a variety of micro-and optoelectronic applications such as the substrates for flexible printed circuit (FPC) and tape automated bonding (TAB), buffer-coating films and interlayer dielectrics for LSI chips, high temperature adhesives, light wave guides for their combined excellent properties, i.e., high glass transition temperatures (T g ), high resistance to chemicals and radiation, relatively low dielectric constants (K or "), and good mechanical properties.1-10 The advantages of PI materials are considerably high purity in the resins, simple production processes, and the ease of structural modifications through copolymerization using various commercially available monomers.Recently, the demands of PIs for the FPC applications have been increasing more and more in the world. Particularly, adhesive-free PI film/Cu laminates (flexible copper clad laminates, FCCL) for FPC fabrications, where the ...

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“…We have reported that when montmorillonite was intercalated with an ammonium salt of 12-aminododecanoic acid, it dispersed at the molecular level into a nylon 6 matrix.' This nylon 6 hybrid had high strength, high modulus, and high heat distortion temperature in comparison with ordinary nylon 6. Therefore, we tried to apply its technique to other polymeric systems.…”

Section: Introductionmentioning

confidence: 99%