Polymer dielectrics with outstanding temperature resistance and mechanical properties are expected to be used in 5G communication systems. Here, self-reinforced cross-linked polyarylene ether nitrile (CPEN) films were rationally designed and fabricated by introducing polyarylene ether nitrile terminated with hydroxyl (PEN-OH) into phthalonitrile end-capped polyarylene ether nitrile (PEN-Ph) and applying post-solid phase chemical reaction. For the catalytic effect on cross-linking reaction and crystallization enhancement of PEN-OH, the comprehensive performance of composite had been greatly improved, which showed a synergistic effect of crosslinking-crystallization. Intriguingly, properties of CPEN films can be finely tuned with the increase of PEN-OH crystallinity. The results show that CPEN films have excellent overall performance with a T_g of 390 °C, a long service life at 300 °C (4.05 × 10² min, 95 wt% residual weight), and low dielectric constant of 2.9. More commendably, CPEN film possessed a higher tensile modulus (3.6 GPa) of over 194% compared to the untreated film due to the crystals immobilized by chemical crosslinking reaction. Tuning the properties of composites by modulating the crosslinking-crystallization behavior opens up a new way to design high-performance polymeric dielectric materials.

具有出色耐温性和机械性能的聚合物电介质有望用于 5G 通信系统。在此，通过将羟基封端的聚亚芳基醚腈（PEN-OH）引入邻苯二甲腈封端的聚亚芳基醚腈（PEN-Ph）中，并应用后处理，合理设计和制造了自增强交联聚亚芳基醚腈（CPEN）薄膜。固相化学反应。PEN-OH对交联反应和结晶增强的催化作用，使复合材料的综合性能有了很大提高，表现出交联-结晶的协同作用。有趣的是，CPEN 薄膜的性能可以随着 PEN-OH 结晶度的增加而微调。结果表明，CPEN薄膜具有优异的综合性能，T _g为 390 °C，在 300 °C 下具有较长的使用寿命（4.05 × 10 ²  min，95 wt% 剩余重量），以及 2.9 的低介电常数。更值得称道的是，由于晶体通过化学交联反应固定，CPEN 薄膜的拉伸模量（3.6 GPa）比未经处理的薄膜高出 194% 以上。通过调节交联-结晶行为来调整复合材料的性能为设计高性能聚合物介电材料开辟了一条新途径。