A covering material for an optical-fiber sensor used for an apparatus for detecting leakage oil by using the change in light propagation loss or in intensity of backscattering light produced in an optical fiber. The covering material has a refractive index smaller than that of a core or clad material of the optical fiber and consists of the polymer (I) obtained by polymerizing a monomer (A) mainly composed of the monomer having polymerizable unsaturated groups in the molecule made of the monomer with the solubility parameter (SP value) of 9 or less and/or the monomer having polyalkylsiloxane groups or fluorohydrocarbon groups.
一种光纤传感器的覆盖材料,用于利用光纤中产生的光传播损耗或背向散射光强度的变化来检测漏油的设备。该覆盖材料的折射率小于光纤芯材或包层材料的折射率,由
聚合物 (I) 组成,
聚合物 (I) 是通过聚合单体 (A) 而获得的,单体 (A) 主要由分子中具有可聚合不饱和基团的单体组成,单体的溶解度参数 (
SP 值) 为 9 或以下,和/或单体具有聚烷基
硅氧烷基团或
氟烃基团。