Characterization of Comb-Shaped Copolymers by Multidetection SEC, DLS and SANS

Giulia Gelardi (1) , Nicolas Sanson (2) , Gergely Nagy (3) , Robert Flatt (1)

1 Institute for Building Materials
2 SIMM - Sciences et Ingénierie de la Matière Molle
3 LNS - Laboratory for Neutron Scattering and Imaging [Paul Scherrer Institute]

PolyCarboxylate ether-based superplasticizers (PCEs) are a type of comb-shaped copolymers used as polymeric dispersants in cementitious materials. PCEs have a high degree of dispersity, which limits the suitability of conventional characterization techniques, such as Size Exclusion Chromatography (SEC). Properties of PCEs strongly depend on their molecular structure and a comprehensive characterization is needed to fully understand the structure–property relationships. PCEs with well-defined molecular structures were synthesized to study their solution conformation by SEC and scattering techniques. The combined use of SEC, dynamic light scattering and small-angle neutron scattering allowed us to demonstrate the validity of a scaling law describing the radius of gyration of comb-shaped copolymers as a function of their molecular structure. Moreover, we show that the use of SEC with standard calibration, although widely spread, is not adequate for PCEs

Mots clés: comb-shaped copolymers; superplasticizer; solution conformation; radius of gyration; multidetection size-exclusion chromatography; dynamic light scattering; small-angle neutron scattering

Domaines: Matière Molle [cond-mat.soft]

Giulia Gelardi, Nicolas Sanson, Gergely Nagy, Robert Flatt. Characterization of Comb-Shaped Copolymers by Multidetection SEC, DLS and SANS. Polymers, 2017, 9 (2), pp.61. ⟨10.3390/polym9020061⟩. ⟨hal-01474074⟩