Commercially Used Sulphate Binders Based on Anhydrite

Abstract

The work was devoted to the analysis of a commercially manufactured binder imported from Germany which is supposed to represent a natural anhydrite according to the accompanying documentation, industrially modified by hydration process activating agents. A similar analysis of the anhydrite binder commercially manufactured in Germany was carried out at the very beginning of investigation into the given problem. In the introductory study of applied research engaged in the feasibility of preparation of self-levelling mixes based on anhydrite binder, a specimen binder made by a German producer declared as a purely anhydrite binder, was analysed. However, it was found out by the analyses performed that this binder is a premium quality -gypsum according to all manifestations by a modified liquefying and retarding agent, possibly by other compounds. Due to potential changes that may have occurred since the initial study in the composition of the so-called anhydrite binders, exploration of composition of the binders currently used in the Czech Republic for preparation of self-levelling mixtures was carried out in this part of the experimental work. The exploration detected that the composition of the binding phase is the matter of know-how for the majority of companies, and as a result, the only one sample of binder has been obtained so far from the company which reserved their anonymity for this work.