Transparent and high permittivity films of poly(methyl methacrylate)-grafted 7 nm barium titanate particles prepared by surface-initiated atom transfer radical polymerization
Transparent and high permittivity films of poly(methyl methacrylate)-grafted 7 nm barium titanate particles prepared by surface-initiated atom transfer radical polymerization
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DOI：
10.1016/j.polymer.2015.11.010
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发表时间：
2015-12
期刊：
影响因子：
4.6
通讯作者：
Naoto Iwata;Osamu Sato;K. Ohno;Koichi Sakajiri;Sungmin Kang;M. Tokita
中科院分区：
文献类型：
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作者：
Naoto Iwata;Osamu Sato;K. Ohno;Koichi Sakajiri;Sungmin Kang;M. Tokita
采用熔融压制法制备了聚甲基丙烯酸甲酯（PMMA）接枝7 nm钛酸钡（BT）粒子的透明高介电常数薄膜。通过表面引发的甲基丙烯酸甲酯原子转移自由基聚合，将分子量为32-40 kDa的PMMA链以0.2-0.7链nm− 1的密度接枝到BT颗粒表面。这产生了BT/PMMA复合材料，其中BT体积分数（φ）为3.2%至10%。在熔融压制的BT/PMMA复合膜中，BT颗粒分散均匀，在550 nm处具有较高的透过率，100 μm厚度的标准化透过率为80%。根据Lichtenecker的对数混合公式，在1 kHz和25 °C下，当φ增加到10%时，薄膜的相对介电常数增加到4.1，而损耗角正切保持低至0.04。
Transparent and high permittivity films were prepared by melt pressing poly(methyl methacrylate) (PMMA)-grafted 7 nm barium titanate (BT) particles. PMMA chains with molecular weights of 32–40 kDa were grafted on BT particle surfaces at a density of 0.2–0.7 chains nm−1through surface-initiated atom transfer radical polymerization of methyl methacrylate. This yielded BT/PMMA composites with BT volume fractions (φ) ranging from 3.2% to 10%. In melt-pressed BT/PMMA composite films, BT particles were well-dispersed and exhibited high transmittance at 550 nm, with the values standardized for 100 μm thickness being 80%. The relative permittivity of the films at 1 kHz and 25 °C increased to 4.1 upon increasingφto 10%, according to Lichtenecker's logarithmic mixture formula, while the loss tangent remained as low as 0.04.