BaTiO3/epoxy composites consisting of two three-dimensionally interpenetrating networks of BaTiO3 and epoxy phases were prepared using a new approach. The BaTiO3/epoxy composites exhibit a colossal dielectric constant...BaTiO3/epoxy composites consisting of two three-dimensionally interpenetrating networks of BaTiO3 and epoxy phases were prepared using a new approach. The BaTiO3/epoxy composites exhibit a colossal dielectric constant, low dielectric loss and high flexural strength. In the BaTiO3 networks, chemically bonded grain boundaries between neighboring BaTiO3 grains were established, and they are responsible for the colossal dielectric constant and high flexural strength of the BaTiO3/epoxy composites. Furthermore, unlike the conventional ceramic/polymer composites, this approach also makes high loadings of BaTiO3 contents possible for the BaTiO3/epoxy composites without compromising their high flexural strength.展开更多
用硅烷和钛酸酯偶联剂对 Ba Ti O3粉进行了表面处理 ,使用溶剂法制备了 PVDF/Ba Ti O3复合薄膜。通过疏水亲油实验定性地分析了硅烷和钛酸酯偶联剂对 Ba Ti O3粉的偶联作用可以改善 PVDF/Ba-Ti O3的界面结合 ,通过测定 PVDF/Ba Ti O3的...用硅烷和钛酸酯偶联剂对 Ba Ti O3粉进行了表面处理 ,使用溶剂法制备了 PVDF/Ba Ti O3复合薄膜。通过疏水亲油实验定性地分析了硅烷和钛酸酯偶联剂对 Ba Ti O3粉的偶联作用可以改善 PVDF/Ba-Ti O3的界面结合 ,通过测定 PVDF/Ba Ti O3的介电常数和介电损耗角正切值表征了复合材料的介电性能 ,PVDF/Ba Ti O3扫描电子显微镜 (SEM)的微观形态分析发现 ,经过偶联剂表面处理 ,Ba Ti O3粉在PVDF中的分散情况改善 。展开更多
研究了在 Ba Ti O3水浆料中通过加入丙烯酰胺有机单体原位聚合形成聚丙烯酰胺的过程制备厚膜。生坯的柔韧性通过加入丙三醇作为增塑剂加以改善。实验结果表明 ,由于所制备浆料的均匀性好 ,这种由原位聚合形成的厚膜显微结构均匀 ,电性...研究了在 Ba Ti O3水浆料中通过加入丙烯酰胺有机单体原位聚合形成聚丙烯酰胺的过程制备厚膜。生坯的柔韧性通过加入丙三醇作为增塑剂加以改善。实验结果表明 ,由于所制备浆料的均匀性好 ,这种由原位聚合形成的厚膜显微结构均匀 ,电性能优良。展开更多
BaTiO 3 ceramics doped with Nd 2 O 3 (the additive content was respectively 0.001,0.002,0.003,0.005,0.01,0.03mol)were prepared by Sol-Gel method.Effects of Nd 2 O 3 contents on the dielectric constant (ε),the dielect...BaTiO 3 ceramics doped with Nd 2 O 3 (the additive content was respectively 0.001,0.002,0.003,0.005,0.01,0.03mol)were prepared by Sol-Gel method.Effects of Nd 2 O 3 contents on the dielectric constant (ε),the dielectric loss(tanδ),the Curie-temperature(T C )and the resistivity(ρ)of BaTiO 3 ceramic were studied.When Nd 2 O 3 content was 0.001mol and 0.002mol,t he dielectric constant was increase d obviously,but the dielectric loss was also increased.When Nd 2 O 3 content was 0.003mol,the dielectric constant was increased,and the die lectric loss was decreased,which was suitable fo r application in condenser.The resistivity was decreased obviously with the increasing of Nd 2 O 3 contents,the resistivity was the sm allest when Nd 2 O 3 content was 0.001mol.The Curie-temperature was also decreased with the increasing of Nd 2 O 3 contents.展开更多
基金Funded by the National Natural Science Foundation of China(Nos.21571095 and 51362020)the Jiangxi Provincial Department of Education(KJLD13008)
文摘BaTiO3/epoxy composites consisting of two three-dimensionally interpenetrating networks of BaTiO3 and epoxy phases were prepared using a new approach. The BaTiO3/epoxy composites exhibit a colossal dielectric constant, low dielectric loss and high flexural strength. In the BaTiO3 networks, chemically bonded grain boundaries between neighboring BaTiO3 grains were established, and they are responsible for the colossal dielectric constant and high flexural strength of the BaTiO3/epoxy composites. Furthermore, unlike the conventional ceramic/polymer composites, this approach also makes high loadings of BaTiO3 contents possible for the BaTiO3/epoxy composites without compromising their high flexural strength.
文摘用硅烷和钛酸酯偶联剂对 Ba Ti O3粉进行了表面处理 ,使用溶剂法制备了 PVDF/Ba Ti O3复合薄膜。通过疏水亲油实验定性地分析了硅烷和钛酸酯偶联剂对 Ba Ti O3粉的偶联作用可以改善 PVDF/Ba-Ti O3的界面结合 ,通过测定 PVDF/Ba Ti O3的介电常数和介电损耗角正切值表征了复合材料的介电性能 ,PVDF/Ba Ti O3扫描电子显微镜 (SEM)的微观形态分析发现 ,经过偶联剂表面处理 ,Ba Ti O3粉在PVDF中的分散情况改善 。
文摘BaTiO 3 ceramics doped with Nd 2 O 3 (the additive content was respectively 0.001,0.002,0.003,0.005,0.01,0.03mol)were prepared by Sol-Gel method.Effects of Nd 2 O 3 contents on the dielectric constant (ε),the dielectric loss(tanδ),the Curie-temperature(T C )and the resistivity(ρ)of BaTiO 3 ceramic were studied.When Nd 2 O 3 content was 0.001mol and 0.002mol,t he dielectric constant was increase d obviously,but the dielectric loss was also increased.When Nd 2 O 3 content was 0.003mol,the dielectric constant was increased,and the die lectric loss was decreased,which was suitable fo r application in condenser.The resistivity was decreased obviously with the increasing of Nd 2 O 3 contents,the resistivity was the sm allest when Nd 2 O 3 content was 0.001mol.The Curie-temperature was also decreased with the increasing of Nd 2 O 3 contents.
文摘采用静电纺丝法制备了平均直径分别为180 nm和220 nm的BaTiO3（BTO）和Ni0.4Co0.2Zn0.4Fe2O4（NCZFO）纳米纤维,使用X射线衍射（XRD）、场发射扫描电镜（FESEM）和矢量网络分析仪（VNA）对纤维的物相结构、表面形貌和微波电磁参数进行了表征,并根据传输线理论分析评估了以BTO和NCZFO纳米纤维为吸收剂的硅橡胶基单层和双层结构吸波涂层在2~18 GHz范围内的微波吸收性能。结果显示,由于BTO纳米纤维的介电损耗与NCZFO纳米纤维的磁损耗的有机结合和阻抗匹配特性的改善,以NCZFO纳米纤维/硅橡胶复合体（S1）为匹配层、BTO纳米纤维/硅橡胶复合体（S2）为吸收层的双层吸波涂层比相应单层吸波涂层表现出更为优异的吸收性能。通过调节匹配层与吸收层的厚度,在4.9~18 GHz范围内反射损耗可达–20 d B以下;当吸收层和匹配层的厚度分别为2.3 mm和0.5 mm时,最小反射损耗位于9.5 GHz达–87.8 d B,低于–20 d B的吸收带宽为5 GHz。优化设计的NCZFO/BTO纳米纤维双层吸波涂层有望发展成为一种新型的宽频带强吸收吸波材料。
