Suppressing Syneresis in Poly(<italic style="font-style: italic">N</italic>-isopropylacrylamide) Hydrogels by Incorporating Poly(ethylene glycol)

Hao-Dong Hu; Yu Kang; Jian Tang; Quan Chen

doi:10.1007/s10118-025-3354-2

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Suppressing Syneresis in Poly(N-isopropylacrylamide) Hydrogels by Incorporating Poly(ethylene glycol)

RESEARCH ARTICLE | Updated：2025-07-26

- Suppressing Syneresis in Poly(N-isopropylacrylamide) Hydrogels by Incorporating Poly(ethylene glycol)
- Chinese Journal of Polymer Science Vol. 43, Issue 8, Pages: 1415-1422(2025)
- Affiliations：
  
  a.State Key Laboratory of Polymer Science and Technology, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China
  b.School of Applied Chemistry and Engineering, University of Science and Technology of China, Hefei 230026, China
- Author bio：
  
  tangjian@ciac.ac.cn (J.T.)
  qchen@ciac.ac.cn (Q.C.)
- Funds：
- DOI：10.1007/s10118-025-3354-2
  CLC： M
- Received：14 February 2025，
  
  Revised：2025-03-19，
  
  Accepted：10 April 2025，
  
  Online First：18 June 2025，
  
  Published：01 August 2025
- Accepted：
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Hu, H. D.; Kang, Y.; Tang, J.; Chen, Q. Suppressing syneresis in poly(N-isopropylacrylamide) hydrogels by incorporating poly(ethylene glycol). Chinese J. Polym. Sci. 2025, 43, 1415–1422

Hao-Dong Hu, Yu Kang, Jian Tang, et al. Suppressing Syneresis in Poly(N-isopropylacrylamide) Hydrogels by Incorporating Poly(ethylene glycol)[J]. Chinese Journal of Polymer Science, 2025, 43(8): 1415-1422. DOI: 10.1007/s10118-025-3354-2.
Hu, H. D.; Kang, Y.; Tang, J.; Chen, Q. Suppressing syneresis in poly(N-isopropylacrylamide) hydrogels by incorporating poly(ethylene glycol). Chinese J. Polym. Sci. 2025, 43, 1415–1422 DOI： 10.1007/s10118-025-3354-2.

Hao-Dong Hu, Yu Kang, Jian Tang, et al. Suppressing Syneresis in Poly(N-isopropylacrylamide) Hydrogels by Incorporating Poly(ethylene glycol)[J]. Chinese Journal of Polymer Science, 2025, 43(8): 1415-1422. DOI: 10.1007/s10118-025-3354-2. DOI：

摘要

Shape-reversible hydrogels are achieved by copolymerizing PNIPAm with hydrophilic PEG

which enables water expelled from the PNIPAm-rich phase during heating to be temporarily absorbed by the PEG-rich phase; this recoverability depends on the swellability of PEG

determined by its molecular weight and concentration.

Abstract

Thermoresponsive hydrogels based on poly(

-isopropylacrylamide) (PNIPAm) often undergo syneresis upon heating

and thus become irrecoverable in shape. To overcome this limitation

we copolymerize tetra-armed PNIPAm precursor with tetra-armed poly(ethylene glycol) (PEG) precursor. After incorporating the hydrophilic PEG components

the hydrogel samples exhibited recoverable swellability during repeated heating-cooling cycles

during which phase segregation occurred

and the water repelled from the PNIPAm-rich phase can be accommodated in the PEG-rich phase. As a result

recoverability relied on the swellability of the PEG-rich phase

which correlated quantitatively with the molar mass and concentration of the precursor solution. This study provides an effective p

rotocol for the molecular design of stimuli-responsive hydrogels with a desired degree of shape recoverability.

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Keywords

references

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Suppressing Syneresis in Poly(N-isopropylacrylamide) Hydrogels by Incorporating Poly(ethylene glycol)

DOI：10.1007/s10118-025-3354-2

摘要

Abstract

关键词

Keywords

references