Abstract We have deeply diminished the density of high performance aromatic polyamides or aramids. Thus, we have prepared microcellular films that at the same time maintain the outstanding thermal and mechanical properties characteristic of these high performance materials. Two different cellular aramids were produced, based on commercial poly(m-phenylene isophthalamide), one of them with an additional azide group. Microcellular structures have been obtained by adding ionic liquids combined to ScCO2 foaming process, with cell sizes between 0.6 and 4.7 µm and cell densities between 109 and 1011 cells cm3. The density was lowered for the commercial poly(m-phenylene isophthalamide) (Nomex® and Teijin Conex®) from 1.43 to 0.62 g cm−3 and from 1.48 to 0.31 g cm3 for the aramid containing the azide group. Foams present the following thermal and mechanical properties: 5% weight loss observed at T > 400 °C and relative Young modulus and tensile strength of 1.2 GPa (g cm−3)−1 and 60 MPa (g cm−3)−1, respectively.

中文翻译：

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微孔发泡芳香族聚酰胺（芳纶）。结构、热学和机械性能

摘要 我们大大降低了高性能芳族聚酰胺或芳纶的密度。因此，我们制备了微孔薄膜，同时保持了这些高性能材料出色的热性能和机械性能。基于商业聚（间苯二甲酰间苯二甲酰胺），生产了两种不同的蜂窝状芳纶，其中一种具有额外的叠氮化物基团。通过将离子液体加入 ScCO2 发泡工艺，获得了微孔结构，孔尺寸在 0.6 到 4.7 µm 之间，孔密度在 109 到 1011 孔 cm3 之间。商业聚（间苯二甲酰间苯二甲酰胺）（Nomex® 和 Teijin Conex®）的密度从 1.43 到 0.62 g cm-3，对于含有叠氮基的芳族聚酰胺，密度从 1.48 到 0.31 g cm3。