Compared with chemical modification of ferroelectric poly (vinylidene fluoride) (PVDF) for electric energy storage, polymer blends, whether miscible or immiscible, represent a much easier approach to suppress the ferroelectricity of PVDF. In this study, we explored both miscible [i.e., poly (methyl methacrylate) or PMMA] and immiscible (i.e., polycarbonate or PC) blends with poly (VDF-co-hexafluoroethylene) [P(VDF-HFP)], as well as the PC/P(VDF-HFP) multilayer films. For miscible PMMA/P(VDF-HFP) blend films, the addition of PMMA significantly decreased the crystallinity of P(VDF-HFP). At a high PMMA content of ca. 40 wt%, the stretched PMMA/P(VDF-HFP) blend films started to exhibit the linear dielectric behavior with suppressed ferroelectricity. For the immiscible PC/P(VDF-HFP) blend films, a high PC content of ∼50 vol% was required to suppress the ferroelectricity in P(VDF-HFP). Instead, the PC/P(VDF-HFP) multilayer films started to show linear hysteresis loops when the content of P(VDF-HFP) was only 30 vol%. More importantly, the PC/P(VDF-HFP) multilayer films exhibited significantly higher breakdown strength than the blend films. This could be attributed to the perpendicular interfaces (with respect to the applied electric field), which serve as effective blocks for hot electrons injected from the metal electrodes to pass through the film. From this study, compared to conventional miscible and immiscible blends, multilayer films are promising for next generation film capacitors, aiming to achieve high temperature tolerance, high energy density, and low loss simultaneously.

与用于储电的铁电聚偏二氟乙烯（PVDF）的化学改性相比，无论是可混溶还是不可混溶的聚合物共混物，都是抑制PVDF铁电性的更容易方法。在这项研究中，我们研究了与聚（VDF- co-六氟乙烯）[P（VDF-HFP）]以及PC / P（VD​​F-HFP）多层膜。对于可混溶的PMMA / P（VD​​F-HFP）混合膜，添加PMMA会显着降低P（VDF-HFP）的结晶度。在高PMMA含量的情况下。40％（重量）时，拉伸的PMMA / P（VD​​F-HFP）共混薄膜开始表现出线性介电行为，并且铁电性受到抑制。对于不混溶的PC / P（VD​​F-HFP）混合膜，需要约50 vol％的高PC含量才能抑制P（VDF-HFP）中的铁电。相反，当P（VDF-HFP）的含量仅为30体积％时，PC / P（VD​​F-HFP）多层膜开始显示线性磁滞回线。更重要的是，PC / P（VD​​F-HFP）多层膜的击穿强度明显高于共混膜。这可以归因于垂直界面（相对于所施加的电场），垂直界面用作从金属电极注入的热电子穿过薄膜的有效块。根据这项研究，与常规的可混溶和不可混溶的共混物相比，多层膜有望用于下一代薄膜电容器，旨在同时实现高温耐受性，高能量密度和低损耗。