کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
7883908 1509645 2018 15 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effect of alkalinity and calcium concentration of pore solution on the swelling and ionic exchange of superabsorbent polymers in cement paste
ترجمه فارسی عنوان
اثر قلیایی و غلظت کلسیم محلول منفی بر روی تورم و تبادل یونی پلیمرهای سوپر جذب کننده در خمیر سیمان
موضوعات مرتبط
مهندسی و علوم پایه سایر رشته های مهندسی مهندسی صنعتی و تولید
چکیده انگلیسی
Swelling kinetics of superabsorbent polymers (SAP) in fresh concrete is complex, but its understanding is crucial for optimisation in practical applications. In this study, the effect of concentration of ions common in pore solution (Na+, K+, Ca2+, Cl−, OH−, SO42−) and cyclic wetting/drying on the swelling and ionic exchange of poly(AA) and poly(AA-co-AM) were investigated. Results show that swelling is not a simple function of concentration or ionic strength. In cement paste, SAP absorbs Ca2+ and releases its counterion (Na+, K+) into pore solution. Ca2+ binds with SAP and decreases initial swelling, but the bound Ca2+ can be displaced and swelling gradually recovers. Swelling increases with increase in alkalinity, but decreases with increase in calcium concentration. The higher the degree of ion exchange, the lower the swelling of SAP. Poly(AA) is more susceptible to Ca2+ complexation and therefore achieves a lower swelling ratio and slower swelling recovery compared to poly(AA-co-AM).
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Cement and Concrete Composites - Volume 88, April 2018, Pages 150-164
نویسندگان
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