Semiaromatic Poly Research Articles

New Negative-type Photosensitive Alkaline-developable Semi-aromatic Polyimides with Low Dielectric Constants Based on Poly(amic acid) from Aromatic Diamine Containing Adamantyl Units and Alicyclic Dianhydrides, A Cross-linker, and A Photoacid Generator

A new negative-working and alkaline-developable photosensitive polyimide precursor based on semi-aromatic poly(amic acid)s (4), 4,4′-methylenebis[2,6-bis(hydroxymethyl)]phenol (MBHP) as a cross-linker, and a photoacid generator (5-propylsulfonyloxyimino-5H-thiophen-2-ylidene)-2-(methylphenyl)acetonitrile (PTMA) has been developed. Novel polymers 4 were prepared by ring-opening polyadditions of alicyclic dianhydrides (1), 1,2,3,4-cyclobutanetetracarboxylic dianhydride (1a), bicyclo[2.2.2]oct-7-ene-2,3;5,6-tetracarboxylic dianhydride (1b), and bicyclo[2.2.1]heptane-2-methanecarboxylic-3,5,6-tricarboxylic-2,3:5,6-dianhydride (1c) with 1,3-bis(4-aminophenoxy)adamantane (3). Polymers 4 were converted to corresponding poly(imide)s (5) by thermal treatment. The dielectric constants (ε) of 5 estimated from the refractive indices were 2.72–2.74. The photosensitive polyimide precursor containing 4 (60 wt %), MBHP (30 wt %), and PTMA (10 wt %) cast from 2-methoxyethanol solution showed a clear negative image featuring 15 μm line and space patterns when it was exposed to 436 nm light, post-exposure baked at 110 °C for 3 min, followed by developing with 2.38 wt % aqueous tetramethylammonium hydroxide (TMAH) solution at 25 °C for 40 s.

Novel diols containing ester and amide groups and resulting poly(ester amide ester)s

AbstractThe reaction of terephthaloyl chloride and 4‐hydroxybenzoic acid resulted in terephthalyl bis(4‐oxybenzoic) acid. This diester diacid was converted into its corresponding diester diacid chloride (terephthaloyl dioxydibenzoylchloride) via a reaction with thionyl chloride. Diols with preformed ester and amide groups were prepared through the reaction of terephthaloyl dioxydibenzoylchloride with 4‐aminophenol and 5‐amino‐1‐naphthol. Polycondensation reactions of the prepared diols with different aromatic and aliphatic diacid chlorides afforded eight aromatic and semiaromatic poly(ester amide ester)s. The polymers were fully characterized, and their physical and thermal properties were studied. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2699–2703, 2004

Studies on thermotropic liquid crystalline polymers. XIV. Synthesis and properties of liquid crystalline poly(imide-ester)s by the direct polycondensation

A series of semi-aromatic poly(imide-ester)s were prepared by the direct polycondensation of N-(4-carboxyphenyl) trimellitimide or N-(3-carboxyphenyl) trimellitimide with various pyromellitic diimide diols containing methylene spacer = 2-6, respectively. The effect of the amount of LiCI, pyridine, and the kinds of condensation agents on the direct polycondensation were studied. The structures and thermal properties of the synthesized poly(imide-ester)s were examined by FTIR spectrum, wide-angle x-ray diffraction (WAXD), differential scanning calorimetry (DSC), thermal optical polarized microscopic observation, and thermogravimetric analysis (TGA). It is found that P1 series [derived from N-(4-carboxyphenyl) trimellitimide] with even number methylene spacer (n = 4, 6) exhibit smectic mesophase, but P2 series [derived from N-(3-carboxyphenyl) trimellitimide] do not show LC phase.