TY - JOUR
T1 - Water-based latex dispersions. 5
T2 - NMR relaxation studies of deuterium labeled nonylphenol ethoxylate
AU - Boissier, Catherine
AU - Holmberg, Krister
AU - Löfroth, Jan-Erik
AU - Nydén, Magnus
PY - 2009
Y1 - 2009
N2 - 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.
AB - 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.
KW - ²H relaxation
KW - nonylphenol ethoxylate
KW - nuclear magnetic resonance (NMR)
KW - polystyrene
KW - silica
UR - http://www.scopus.com/inward/record.url?scp=70449369472&partnerID=8YFLogxK
U2 - 10.1080/01932690802644061
DO - 10.1080/01932690802644061
M3 - Article
AN - SCOPUS:70449369472
VL - 30
SP - 873
EP - 880
JO - Journal of Dispersion Science and Technology
JF - Journal of Dispersion Science and Technology
SN - 0193-2691
IS - 6
ER -