1994 Volume 5 Issue 1 Pages 99-108
Polymer dispersions have been used in polymer-modified mortars for many years, and are also being used as sealers for bed concrete of mortar or tile finished exterior walls. This study mainly deals with the stability of polymer films formed with polymer dispersions in alkali environment, and the influence of alkali on the physical properties of the polymer films in polymer-modified mortars. The conclusions obtained are summarised as follows : (1) Homopolymers containing ester linkage and copolymers containing vinyl acetate are less stable in alkali environment, because their chemical structures are altered by the alkali. (2) Polymer films formed with polymer dispersions are used as sealers are apt to deteriorate compared with polymer films in polymer-modified mortars. The reason for this may be explained to be due to the difference of exposure conditions of the polymer films to concentrated alkali such as in pore solution.
