Title:
PCEs Molecular Structure Formation for Gypsum and Cement-Gypsum Binders
Author(s):
Anatoly I. Vovk
Publication:
Symposium Paper
Volume:
354
Issue:
Appears on pages(s):
225-232
Keywords:
polycarboxylate, gypsum, structure-property relationship
DOI:
10.14359/51736076
Date:
7/1/2022
Abstract:
Over the past decades, PCEs have become the most popular superplasticizer type in all industrialized countries. This was undoubtedly promoted by the inherent in PCEs “design flexibility”, i.e., the ability to create a molecular structure according to the needs of concrete technology. With understandable and relatively small variations in the structure and composition, PCEs have shown to be effective for all types of Portland cement and their combinations with SCMs. However, when transferring to gypsum and gypsum-cement binders, widely used in dry mixes, standard PCEs proved to be ineffective. Ideas on the preferred PCEs structure for these binders were formulated, and a methodology has been developed for physicochemical evaluation of the PCEs efficiency for gypsum or binders with a high gypsum content. The technical efficiency of the synthesized PCEs in the self-leveling screeds based on various gypsum was confirmed in comparison with the specialized commercially available PCEs of various companies.
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