Alessandro Russo, Andreas Schorer, Marco Rentsch, Giuseppe Nese, Fabio Montagnaro* and Luciano Santoro Pages 27 - 47 ( 21 )
Objective: Aim of this paper is to investigate the interactions between industrial-grade polycarboxylate ether (PCE) polymers and ordinary Portland cement to assess whether is possible to draw structure/performance relations for impure, yet fully characterized, polymers.
Method: To this end thirteen PCE polymers were synthesised in industrial fashion, deeply analyzed and tested in cement paste. Chemical stability and adsorption behaviour have been evaluated through gel permeation chromatography technique, leading to insights regarding the plasticization timing and the adsorption control.
Results: All the results were interpreted and critically discussed by invoking the characteristics of initial dispersers and workability retainers; furthermore a comprehensive description has been attempted through the Gay and Raphael conformation plot, based on the establishment of which molecular feature affects each step of the PCE's working mechanism.
Conclusion: The results confirm many of the findings despite the imperfect nature of the chosen polymers and show that common impurities, such as unreacted side chains, do not noticeably interact with the binder. In particular it is clear that the limiting stage of the entire action lies on adsorption rate and occurrence, which seems to be ruled by the absolute value of charge per chain and by the conformation regime.
Adsorption, initial dispersers, ordinary portland cement, polycarboxylate ether, superplasticizers, workability retainers.
CEMEX Research Group AG, Romerstrasse 13, 2555 Brugg b. Biel, CEMEX Research Group AG, Romerstrasse 13, 2555 Brugg b. Biel, CEMEX Research Group AG, Romerstrasse 13, 2555 Brugg b. Biel, Dipartimento di Scienze Chimiche, Universita degli Studi di Napoli Federico II, Complesso Universitario di Monte Sant'Angelo, 80126 Napoli, University of Naples , Dipartimento di Scienze Chimiche, Universita degli Studi di Napoli Federico II, Complesso Universitario di Monte Sant'Angelo, 80126 Napoli