Fire-retardant, self-extinguishing multiblock poly(esterimide)s/graphene composites with segregated structure for electromagnetic interference shielding
Fire-retardant, self-extinguishing multiblock poly(esterimide)s/graphene composites with segregated structure for electromagnetic interference shielding
复制标题
用于电磁干扰屏蔽的具有隔离结构的阻燃、自熄性多嵌段聚酯酰亚胺/石墨烯复合材料
DOI：
10.1016/j.compositesa.2022.107262
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发表时间：
2022
期刊：
影响因子：
--
通讯作者：
Meifang Zhu
中科院分区：
文献类型：
--
作者：
Xiaowen Wang;Paul Smith;Zhe Qiang;Qingbao Guan;Zhengwei You;Changhuai Ye;Meifang Zhu
基于全芳香族液晶聚合物 (LCP) 的隔离导电复合材料是电磁干扰 (EMI) 屏蔽的理想候选材料。然而，由于液晶向列相转变温度下粘度急剧下降以及 LCP 的熔体粘度非常低，构建偏析 LCP 复合材料仍然存在巨大挑战。在此，基于全芳香族多嵌段聚酯酰亚胺（BPEI）和具有明确分离结构的多层石墨烯（MLG）的导电复合材料是通过具有宽加工窗口的固态压缩成型来制造的，这是通过源自合成的BPEI嵌段共聚物的两个截然不同的玻璃化转变温度的橡胶状态下的适当粘度实现的。具有 5.0 wt% MLG 负载量的分离 BPEI/MLG 复合材料可在仅 2.3 mm 的厚度下实现 313.5 S/m 的超高电导率和 62.2 dB 的高 EMI 屏蔽效能。此外，分离的BPEI/MLG复合材料表现出高热稳定性和出色的阻燃性。
Segregated conductive composites based on all-aromatic liquid crystal polymers (LCPs) are ideal material candidates for electromagnetic interference (EMI) shielding. However, grand challenges still remain for constructing segregated LCP composites due to the sharp viscosity decrease at crystal-to-nematic transition temperature and the very low melt-viscosity of LCPs. Herein, conductive composites based on all-aromatic multiblock poly(esterimide)s (BPEI) and multilayer graphene (MLG) with well-defined segregated structure were fabricated by solid-state compression molding with a broad processing window, which was enabled by the appropriate viscosity at the rubbery state originating from the two very distinct glass transition temperatures of the as-synthesized BPEI block copolymer. The segregated BPEI/MLG composite with 5.0 wt% MLG loading achieves an ultrahigh electrical conductivity of 313.5 S/m and a high EMI shielding effectiveness of 62.2 dB at a thickness of only 2.3 mm. Moreover, the segregated BPEI/MLG composites exhibit high thermal stability and outstanding flame retardancy.