Altering the Crosslinking Density of Polyacrylamide Hydrogels to Increase Swelling Capacity and Promote Calcium Hydroxide Growth in Cement Voids
| Autor: | Carlos J. Martinez, Baishakhi Bose, Cole R. Davis, Kendra A. Erk, Alejandro M. Alcaraz |
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| Rok vydání: | 2019 |
| Předmět: |
Cement
Polyacrylamide Hydrogel Polyacrylamide Swelling capacity technology industry and agriculture macromolecular substances chemistry.chemical_compound Compressive strength stomatognathic system chemistry Superabsorbent polymer Chemical engineering parasitic diseases medicine Swelling medicine.symptom Curing (chemistry) |
| Zdroj: | 3rd International Conference on the Application of Superabsorbent Polymers (SAP) and Other New Admixtures Towards Smart Concrete ISBN: 9783030333416 |
| Popis: | Polyacrylamide (PAM) superabsorbent polymer microspheres were synthesized for use as internal curing agents in low water-to-cement ratio mixtures. An increase in PAM swelling capacity in pore solutions was achieved by reducing the crosslinking density during synthesis: 5.1 g/g swelling was observed for 2 wt.% crosslinker and 20.6 g/g for 0.5 wt.% crosslinker. Capillary micromechanical experiments showed that a reduction in crosslinking density decreased the PAM elastic modulus from 1100 ± 310 kPa to 110 ± 15 kPa. Yet all PAM maintained mechanical integrity when mixed with cement and cured under a compressive load. SEM analysis showed hydrated product formation within cement voids left behind by dehydrated PAM. PAM with reduced crosslinking densities resulted in a 26 ± 7.3% increase in hydrated product formation within these voids. Cement paste density and compressive strength was not compromised by the addition of PAM. |
| Databáze: | OpenAIRE |
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