| 摘要 |
The present invention discloses noncrystalline dibenzofuran polymers composed of repeating units represented by formula (II) and having a molecular weight corresponding to a reduced viscosity of at least 0.2 dl/g as measured for the 0.5 % (W/V) N-methylpyrrolidone solution thereof at 25 DEG C, and a method of producing the same (II). Also disclosed are dibenzofuran copolymers composed of both the repeating units represented by formula (II) and a specified proportion of at least one kind of repeating units represented by general formula (III) and having a molecular weight corresponding to a reduced viscosity of at least 0.2 dl/g as measured for the 0.5 % (W/V) concentrated sulfuric acid solution thereof at 25 DEG C, and a method of producing the same, wherein A represents -O-, -CO-, -S-, -SO2-, an alkylene group or a single bond, and n is 0, 1 or 2. Further disclosed are benzofuran derivatives useful as the starting material of the aforementioned polymers and copolymers, and a method of producing these derivatives. The obtained noncrystalline polymers and copolymers are excellent in the stability during molding and have reduced polarity and hygroscopicity, so that they are useful as the molding material for various applications. |
