In this study, poly(methyl methacrylate) (PMMA)/carbon black (CB), PMMA/carbon fiber (CF), and PMMA/carbon nanotube (CNT) conductive composite films with different filler concentrations are prepared using the solution casting technique. Both perpendicular and in‐plane direction conductivity of all the binary composite films are investigated, percolation thresholds (ϕ_c) of both directions of PMMA/CB, PMMA/CF, and PMMA/CNT composite films are investigated and the experimental data are fitted using McLachlan’s equation. For all the three investigated films, the perpendicular ϕ_c,⊥ and in‐plane ϕ_c,∥ with different fillers show totally different behaviors. Pristine CB, CF, and CNT as well as PMMA/CB, PMMA/CF, and PMMA/CNT composite films are discussed. The gravity effect of the fillers is found to be most significant in the PMMA/CB system. A schematic diagram of PMMA composite films with CB, CF, and CNT as filler prepared from solution casting process is presented to explain the distribution gradient of the fillers in the perpendicular direction of the film after solution casting. A power law behavior is revealed for different filler types (CB, CF, CNT) correlating the exponent t for McLachlan’s equation and corresponding ϕ_c for in‐plane and perpendicular directions.

中文翻译：

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溶液浇铸法制备的填充有碳基填料的聚（甲基丙烯酸甲酯）复合膜的垂直和平面内电导率

在这项研究中，使用溶液流延技术制备了具有不同填料浓度的聚甲基丙烯酸甲酯（PMMA）/炭黑（CB），PMMA /碳纤维（CF）和PMMA /碳纳米管（CNT）导电复合膜。研究了所有二元复合膜的垂直和面内方向电导率，研究了PMMA / CB，PMMA / CF和PMMA / CNT复合膜两个方向的渗透阈值（ϕ _c），并使用麦克拉克兰方程。对于所有三部研究的胶片，垂直方向ϕ _c，⊥和面内ϕ _c，∥具有不同填料的填料表现出完全不同的行为。讨论了原始的CB，CF和CNT以及PMMA / CB，PMMA / CF和PMMA / CNT复合膜。发现填料的重力作用在PMMA / CB系统中最为明显。通过溶液流延法制备了以CB，CF和CNT为填料的PMMA复合薄膜的示意图，以解释溶液流延后填料在薄膜垂直方向上的分布梯度。揭示了不同填料类型（CB，CF，CNT）的幂律行为，这与麦克拉克兰方程的指数t和面内和垂直方向的相应ϕ _c相关。