含螺环结构的二胺及其聚酰亚胺的合成与性能

Synthesis and Properties of Polyimides Containing Spiro Structure

首先,以双酚A和甲磺酸反应合成出3,3,3',3'-四甲基-6,6'-二羟基-1,1'-螺旋双茚满,然后与2-氯-5-硝基三氟甲苯反应得到3,3,3',3'-四甲基-6,6'-双[4-硝基-2-三氟甲基苯氧基]-1,1'-螺旋双茚满,最后在Pd/C-水合肼还原作用下得到3,3,3',3'-四甲基-6,6'-双[4-氨基-2-三氟甲基苯氧基]-1,1'-螺旋双茚满。采用上述二胺单体分别与1,2,3,4-环丁烷四酸二酐、均苯四甲酸二酐、联苯二酐、3,3',4,4'-二苯醚四酸二酐、3,3',4,4'-二苯酮四酸二酐和六氟二酐通过两步法制备出6种含螺环结构的聚酰亚胺(PI)。采用核磁、红外光谱、X射线衍射、紫外-可见光谱、热重分析、差示扫描量热分析和溶解性测试等手段表征了所得化合物和PI的结构与性能。研究结果表明,这些含螺环的PI主要表现为非晶结构和较大的分子链间距离,且具有良好的溶解性、光学性能和热性能。

The diamine containing Spiro structure and -CF3 group, 4,4′-（（3,3,3′,3′-tetramethyl-2,2′,3,3′-tetrahydro-1,1′-spirobi[indene]-6,6′-diyl）bis（oxy））bis（3-（trifluoromethyl）aniline） was prepared through the nucleophilic substitution reaction of 2-chloro-5-nitrobenzotrifluoride with 3,3,3′,3′-tetramethyl-1,1′-spirobisindane-6,6′-diol in the presence of potassium carbonate to yield the intermediate dinitro compounds, followed by catalytic reduction with hydrazine and Pd/C. Six kinds of Spiro-containing polyimides （PIs） were prepared from the diamine and six kinds of dianhydrides 1,2,3,4-cyclobutanetetracarboxylic dianhydride （CBDA）, pyromellitic dianhydride （PMDA）, 3,3′,4,4′-biphenyl tetracarboxylic diandhydride （BPDA）, 3,3′,4,4′-oxydiphthalic anhydride （ODPA）, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride （BTDA） and 4,4′-hexafluoroisopropylidinedi（phtalic anhydride） （6FDA） via the thermal and chemical imidization of poly（amic acid）s（PAA） separately. The chemical structure and properties of these PIs were characterized by FT-IR, XRD, UV-vis, DSC, TGA and solubility testing. These obtained experimental results show that these PIs containing Spiro structure show excellent optical properties, thermal properties and solubility. These PIs exhibit amorphous and larger intermolecular chain instance. Most PIs show good solubility in some aprotic polar organic solvents such as NMP and DMF, and PIs based on CBDA, 6FDA and ODPA are even soluble in weak polar solvent THF to some extent. PI-CBDA shows the best optical properties in the visible wavelength region （400～700 nm） with the transmittance of 85% at 450 nm. They also exhibit excellent thermal properties, 10% thermal decomposition temperature is above 450 ℃ and the glass transition temperature （Tg） of PI-CBDA and PI-PMDA is 295 ℃ and 283 ℃ respectively. These obtained PIs containing Spiro structure could be used in the microelectronic, opto-electronic and gas separation applications.