Abstract
The soft X-ray transmission microscope, which allows the in situ observation of wet samples of cement at normal pressures with high spatial resolutions (25 nm), was used to observe and compare the effects of two polymers — a water soluble polymer (HPMC — hydroxypropyl methylcellulose) and a latex [EVA-poly(ethylene- co-vinyl acetate)] on the early hydration of C 3S and C 3A. These polymers are used to modify the properties of fresh and hardened mortars and concretes, especially when adhesive characteristics are required. The images show that the cellulose ether delays the hydration of the cementitious particles and promotes the formation of inner products rather than outer products. On the other hand, EVA particles agglomerate around the hydrating C 3S grains, and act as nucleation agents in the development of the composite microstructure. While HPMC slightly changed the aspect of C 3A hydration, EVA inhibited or even prevented the formation of ettringite crystals during the early stage of hydration, and resulted in a cloud of small, bright particles concentrated around the hydrating C 3A grains.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
