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2026 Vol.58, Issue 1 Preview Page

Original Paper

Enhancement of Saline Absorbency in CMC/Starch-Based Superabsorbent Polymers by Incorporation of Sodium Bicarbonate

중탄산나트륨 첨가에 따른 CMC/전분 기반 고흡수성 고분자의 염수 흡수 특성 향상

Chan Hee Shin1*
,
Young Lae Kim2*
,
Byoung-Uk Cho3†
신 찬희1*
,
김 영래2*
,
조 병욱3†
1Department of Pulp and Paper Engineering, College of Forest and Environmental Sciences, Kangwon National University
2Department of Pulp and Paper Engineering, College of Forest and Environmental Sciences, Kangwon National University
3Program of Paper Material Science & Engineering, College of Forest and Environmental Sciences, Kangwon National University
1강원대학교 산림환경과학대학 제지공학과, 학생
2강원대학교 산림환경과학대학 제지공학과, 대학원생
3강원대학교 산림환경과학대학 종이소재과학전공, 교수
†Corresponding Author: E-mail: bucho@kangwon.ac.kr (Address: Program of Paper Material Science & Engineering, College of Forest and Environmental Sciences, Kangwon National University, Chuncheon, 24345, Republic of Korea)
Corresponding Author * These authors contributed equally to this work.
28 February 2026. pp. 102-112
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Abstract

Carboxymethyl cellulose (CMC)/cationic starch (CS)-based superabsorbent polymers (SAPs) were prepared with different sodium bicarbonate (NaHCO3) contents to improve saline absorption behavior while maintaining structural stability. The effects of NaHCO3 addition on network structure, swelling behavior, rheological properties, and mechanical stability under load were systematically investigated. A small amount of NaHCO3 (2.5 wt% on CMC and CS) significantly enhanced saline absorption, which was attributed to partial relaxation of electrostatic interactions between CMC and cationic starch and the formation of additional diffusion pathways. SEM analysis revealed the development of internal porous structures induced by weak foaming associated with CO2 generation during drying. However, increasing NaHCO3 content led to a reduction in gel strength, gel fraction, absorption under load (AUL), and centrifuge retention capacity (CRC) due to decreased effective crosslink density. These results demonstrate that controlled NaHCO3 addition provides an effective strategy to balance saline absorption performance and mechanical stability in eco-friendly polysaccharide-based SAPs.

Keywords
Carboxymethyl cellulose
cationic starch
sodium bicarbonate
superabsorbent polymer
saline absorption
gel stability
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Information
  • Publisher :Korea Technical Association of The Pulp and Paper Industry
  • Publisher(Ko) :한국펄프종이공학회
  • Journal Title :Journal of Korea TAPPI
  • Journal Title(Ko) :펄프종이기술
  • Volume : 58
  • No :1
  • Pages :102-112
  • Received Date : 2026-02-05
  • Revised Date : 2026-02-14
  • Accepted Date : 2026-02-14
  • DOI :https://doi.org/10.7584/JKTAPPI.2026.2.58.1.102
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