An elastic microporous material with tunable optical property

• Polytetrafluoroethylene microporous materials exhibit tunable optical property.
• Anisotropy is found to be closely related to the tunable optical property.
• Such anisotropy materials are potentially useful in dynamical sensor fields.

Taking advantage of the fibrillous network structure, polytetrafluoroethylene (PTFE) microporous materials with different structures were fabricated by a series of mechanical operations including preforming, extrusion, calendaring and stretching. Transparent PTFE microporous materials become inherent white gradually during their elastic deformation, exhibiting the tunable optical property. Liquid penetration induced by the pore size variation during the elastic deformation is proposed to be responsible for such transmittance variation. Meanwhile, transmittance variation can be controlled by manipulating the anisotropy of PTFE microporous materials, which is also closely related to the mechanical property. Therefore, this easily prepared and unique elastic microporous material with tunable optical property has significant potential for optical and dynamical sensor fields.