Toughness and microstructure of anionic polyacrylamide modified potassium magnesium phosphate cement
To study the improvement of anionic polyacrylamide(APAM)on the toughness of potassium magnesium phosphate cement,the anionic polyacrylamide-modified potassium magnesium phosphate cement was used as the research object,and the effect of different content of APAM on the setting time,compressive strength,flexural strength,flexural toughness factor and impact energy of potassium magnesium phosphate cement were studiedthrough pore structure analysis,scanning electron microscope,X-ray diffraction and other microscopic tests.The results demonstrated that the addition of appropriate amount of APAM improved the toughness of magnesium potassium phosphate cement.When the contentof anionic polyacrylamide was less than 2.0%,the flexural toughness factor increased with the increasedcontent of APAM.The addition of APAM did not change the type of hydration products in magnesium potassium phosphate cement,but the morphology and internal structure of the hydration products changed.The APAM formed a colloid intercalation within the structure,thus enhancing the toughness of potassium magnesium phosphate cement.In conclusion,the optimal comprehensive performance was achieved when the APAM content was 2.0%.