The waterproofing characteristics of polymer sodium carboxymethyl-cellulose

The mechanism of waterproofing of sodium carboxymethyl-cellulose is still unknown. In this project some special samples at the ages of 7 and 28 days were tested by means of scanning electron microscope, mercury intrusion porosimeter, and infrared absorption spectrum analyses. A number of filmy matters were found in hardened cement paste combined with sodium carboxymethyl-cellulose. The film was smooth and transparent, and matured well with hydration products. The whole system was seemingly divided into a lot of small areas by the film net. The waterproofing mechanism of the polymer is discussed according to the results of the test. Published by Elsevier Science Ltd.