Abstract
The setting and hydration process of calcium sulphoaluminate (CSA) cement within 24 h in the presence of five grades of cellulose ethers (CE) that have different chemistry or substitution degrees were studied by the Vicat test, ultrasonic test and isothermal calorimetry. X-ray diffraction (XRD) was further utilized to characterize the mineral phases of hydrates. Test results reveal that hydroxyethyl cellulose (HEC) prolongs the setting time less than hydroxyethyl methyl cellulose (HEMC) or hydroxypropyl methyl cellulose (HPMC). Higher CE dosage causes very limited change to the setting time of the mortar with HEMC/HPMC but narrows their gap with HEC. CE advance the second exothermal peak of CSA cement hydration where HEC works the most while highly-substituted HEMC/HPMC do the least. The trend is more pronounced at high dosage. The total hydration heat and the crystalized phases of hydrates are impacted slightly. CE work similarly in mortar on hydration to that in cement paste, but their effect is greatly weakened. A model is proposed to illustrate the hydration process. CE film is suggested to work as a medium for easier water migration that helps with the acceleration of the cement hydration reaction.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.