驻极体的研究现状

驻极体是电介质物理、材料科学、传感器工程及生物医学的重要交叉学科。近年来，驻极体在生物驻极体、驻极体的应用及有机驻极体的非线性光学效应等方面取得了瞩目的进展。文章就上述几个问题，从材料制备、实验方法和驻极体的应用等方面进行了综述。

Studies on the Pyroelectric and Piezoelectric Properties of PT/P(VDF TrFE) Composites

Composites of calcium modified lead titanate (PTCa) powder dispersed in a vinylidene fluoride/trifluoroethylene P(VDF TrFE) copolymer matrix were prepared using solvent casting followed by compression moulding. Two types of samples were prepared, one with only the ceramic phase polarized and the other with both phases polarized. When the ceramic and copolymer phases have polarizations in the same direction, the piezoelectric contributions from the two phases partially cancelled each other while the pyroelectric properties reinforced. Hence, there exists a certain volume fraction of ceramic at which the composite is pyroelectric but not piezoelectric. The electromechanical parameters such as the piezoelectric coefficients d 33 , thickness coupling coefficient k t and the pyroelectric coefficient p were measured and compared to model calculation.