title: Dynamic crossover in hydration water of curing cement paste: the effect of superplasticizer.
abstract: The influence of a new comb-shaped polycarboxylate-based superplasticizer (CSSP) on the hydration kinetics and transport properties of aged cement pastes has been investigated by high-resolution quasi-elastic neutron scattering (QENS) and low temperature differential scanning calorimetry (LT-DSC). A new method of analysis of QENS spectra is proposed. By applying the refined method we were able to access to four independent physical parameters including the self-diffusion coefficient of the hydration water confined in the cement paste. Mean squared displacement (MSD) of the hydrogen atom for mobile water molecules displays a dynamic crossover temperature in agreement with DSC data. The experimental results indicate that CSSP polymer added into cement paste moderates the hydration process and decreases the dynamic crossover temperature of the hydration water.
authors.affiliation: Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors.forename: Hua
authors.initials: H
authors.lastname: Li
authors.forename: Wei-Shan
authors.initials: WS
authors.lastname: Chiang
authors.forename: Emiliano
authors.initials: E
authors.lastname: Fratini
authors.forename: Francesca
authors.initials: F
authors.lastname: Ridi
authors.forename: Francesco
authors.initials: F
authors.lastname: Bausi
authors.forename: Piero
authors.initials: P
authors.lastname: Baglioni
authors.forename: Madhu
authors.initials: M
authors.lastname: Tyagi
authors.forename: Sow-Hsin
authors.initials: SH
authors.lastname: Chen