NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.

Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.

U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

PUBLICATIONS

What Causes the Anomalous Aggregation in Pluronic Aqueous Solutions?

Published

Author(s)

Kuo-Chih Shih, Zhiqiang Shen, Ying Li, Martin Kroger, Shing-Yun Chang, Yun Liu, Mu-Ping Nieh, Hsi-Mei Lai

Abstract

Pluronic (PL) block copolymers has been widely used as delivery carriers, molecular templates for porous media, process additive of affecting rheological behavior. Unlike most surfactant systems, where unimer transforms into micelle with increased surfactant concentration, anomalous large PL aggregates below the critical micelle concentration (CMC) were found throughout four PL types (F108, F127, F88 and P84). We characterized their structures using dynamic light scattering and small-angle X-ray/neutron scattering. The formation rate of these aggregates is promoted through vigorous shear. Molecular dynamic simulations suggest that the exposed PPO segments promote the shear-induced formation of large clusters in spite of slow process. Addition of acid and base (e.g citric acid, acetic acid, HCl and NaOH) in F108 solution significantly suppressed the aggregate formation up to 20 days due to the repulsion force from the attached H3O+ molecules on PEO segment and the reduction of CMC through the salting out effect, respectively.
Citation
Soft Matter
Volume
14
Pub Type
Journals

Download Paper

Local Download

Keywords

Poloxamer, Dynamic Light Scattering, Small-Angle Neutron Scattering, Small-Angle X-ray Scattering, Slow Mode, Micelles, Unimer, Aggregates
Materials

Citation

Shih, K. , Shen, Z. , Li, Y. , Kroger, M. , Chang, S. , Liu, Y. , Nieh, M. and Lai, H. (2018), What Causes the Anomalous Aggregation in Pluronic Aqueous Solutions?, Soft Matter, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=924598 (Accessed October 8, 2025)

Issues

If you have any questions about this publication or are having problems accessing it, please contact [email protected].

Created May 27, 2018, Updated October 12, 2021
Was this page helpful?