Small-angle neutron scattering study on microstructure of poly(N-isopropylacrylamide)-block-poly(ethylene glycol) in water

Ryuhei Motokawa, Annaka Masahiko, Takayuki Nakahira, Satoshi Koizumi

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

By employing small-angle neutron scattering (SANS), we investigated the microstructures of, poly(N-isopropylacrylamide) (PNIPA)-block-poly(ethylene glycol) (PEG) (NE) in deuterated water D 2O, as related to macroscopic behaviors of fluidity, turbidity and synerisis. SANS revealed following results: (i) microphase separation occurs at around above 17°C in a temperature range of transparent sol below 30°C. In the microdomain appeared in the transparent sol state, both block chains of PNIPA and PEG are swollen by water; (ii) for the NE solution of polymer concentration W p > 3.5% (w/v), corresponding to opaque gel above 30°C, a percolated structure, i.e., network-like domain is formed by NE as a result of macrophase separation due to dehydration of the PNIPA chains. As the temperature increases toward 40°C, the network domain is squeezed along a direction parallel to the NE interface, which leads to increase of the interfacial thickness given by swollen PEG chains and to the macroscopic synerisis behavior.

Original languageEnglish
Pages (from-to)213-219
Number of pages7
JournalColloids and Surfaces B: Biointerfaces
Volume38
Issue number3-4 SPEC. ISS.
DOIs
Publication statusPublished - Nov 15 2004

Fingerprint

Small Angle Scattering
Ethylene Glycol
Neutrons
Neutron scattering
Polyethylene glycols
glycols
neutron scattering
ethylene
Polymethyl Methacrylate
Sols
microstructure
Microstructure
Water
water
Microphase separation
Temperature
Fluidity
turbidity
Turbidity
Dehydration

All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Surfaces and Interfaces
  • Physical and Theoretical Chemistry
  • Colloid and Surface Chemistry

Cite this

Small-angle neutron scattering study on microstructure of poly(N-isopropylacrylamide)-block-poly(ethylene glycol) in water. / Motokawa, Ryuhei; Masahiko, Annaka; Nakahira, Takayuki; Koizumi, Satoshi.

In: Colloids and Surfaces B: Biointerfaces, Vol. 38, No. 3-4 SPEC. ISS., 15.11.2004, p. 213-219.

Research output: Contribution to journalArticle

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