A study of polymer-modified mortars by the AC impedance technique

作者：Zhong Shiyun^*; Shi Meilun; Chen Zhiyuan

来源：Cement and Concrete Research, 2002, 32(6): 979-982.

DOI：10.1016/S0008-8846(02)00740-8

• Polymer-modified mortar (PMM)

Cement mortar can be regarded as a composite consisting of the cement paste, fine aggregate, and the interfacial transition zone (ITZ). In this paper, the formation and development of the ITZ of polymer-modified mortar (PMM) was studied by alternating current impedance spectroscopy (ACIS). The test results showed that the AC impedance spectra of the PMMs had the following characteristics: (1) the AC impedance spectra of the fresh PMMs were almost parallel to the imaginary axis;(2) The AC impedance spectra of the hardened PMMs showed a high-frequency part not connected to the intermediate frequency part. This characteristic was maintained over a rather long period, and then obvious changes appeared in the AC impedance spectra. The age at which the impedance spectra of the mortars changed appeared to shorten with an increase of the sand volume fractions (SVFs). These characteristics of the AC impedance spectra of the PMMs were related to the close contact, the packing, and the formation of a mechanically rigid film of the polymer particles.

• 出版日期2002
• 单位同济大学