THE STUDY OF POLYESTER TYPE CONCRETE RETARDER

THE CONTROLL OF RETARDING RATE AND THE TREATMENT PROPERTIES OF VERTICAL CONSTRUCTION JOINT

Abstract

The polyester type concrete retarder (coated on polyethyleneterephtalate film) shows some good retarding effects; the effects are stable and last for a long time, a high waterproof against rain and sprinkling. In this study, we examine the relation between the chemical structure of the polyester and the retarding effects, and we find that the retarding effects can be controlled by the chemical structure concerning with the hydrolysis rate of the polyester. We also examine the treatment properties of vertical construction joint with polyester type retarder, and it shows that the treatment with polyester has almost the same effect as the conventional method, such as tipping.