Water-Based Latex Dispersions. 5: NMR Relaxation Studies of Deuterium Labeled Nonylphenol Ethoxylate
Artikel i vetenskaplig tidskrift, 2009

The dynamics and conformation of the nonionic surfactant NP100 (nonylphenol ethoxylate with an average of 84 oxyethylene units), adsorbed on colloidal silica and on polystyrene latex particles, have been studied by the nuclear magnetic resonance relaxation technique. To obtain specific information about the spin relaxation from the methylene groups situated at the hydroxyl-terminal end of the polyoxyethylene (POE) chain, this part was labeled with deuterium in a two-step synthesis. Spin relaxation studies of the labeled part of the adsorbed surfactant (2H relaxation) suggested that the dynamics was slower in comparison with the spin relaxation of the surfactant in solution. Also, it was seen that the dynamics was slower on the silica surface than on the polystyrene surface. This was in agreement with previous studies on the average proton spin relaxation of the whole POE chain of the surfactant on silica and on polystyrene surfaces. The correlation time constant for the slow motions of the POE chain was calculated to be as large as 7.4 ms for NP100 on the polystyrene particles. Also this was in good agreement with studies made on the exchange dynamics of the surfactant in different dispersions, where it was found that the exchange between the solution and the particles was slow.

different interfacial properties

nuclear-magnetic-resonance

silica

2H relaxation

polystyrene

ether

(NMR)

nonionic surfactants

nonylphenol ethoxylate

dynamics

atomic-force microscopy

colloidal particles

nuclear magnetic resonance

layers

adsorption

film formation

Författare

Catherine Boissier

AstraZeneca AB

Krister Holmberg

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Jan-Erik Löfroth

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

Magnus Nydén

Chalmers, Kemi- och bioteknik, Teknisk ytkemi

SuMo Biomaterials

Journal of Dispersion Science and Technology

0193-2691 (ISSN) 1532-2351 (eISSN)

Vol. 30 873-880

Ämneskategorier

Fysikalisk kemi

DOI

10.1080/01932690802644061