On the effect of particle surface chemistry in film stratification and morphology regulation
Artikel i vetenskaplig tidskrift, 2020

Combinations of colloids and binders are often used to formulate functional coatings. In these mixtures, competition between particle migration, polymer chain diffusion, evaporation and sedimentation affects their respective spatial location and therefore can govern the surface features. In addition to this, the surface chemistry of the nanoparticles (NPs) and the resulting interparticle interactions can play a significant role in dictating the morphology and the properties of resultant films. Hence it would be possible to tune the surface and bulk topology of the films by controlling these parameters. A combination of various acrylic binders with two types of silica sols, bare (BSiO2) and modified silica (MSiO2), differing in their ability to gel, were formulated and dried under controlled conditions. Factors influencing the mobility and migration of binder and silica particles were evaluated with respect to particle concentration and drying rate. MSiO2 films showed prominent pores with gradual increase in Si% across the cross-section of the films, whereas, BSiO2 films had no pores and showed a uniform Si content across the cross-section of the films. This difference is explained by the variation in gelation between BSiO2 compared to MSiO2, that hindered the NPs migration and affects the infiltration and stratification process. This study paves a path forward to achieve desired surface and bulk porosity from colloidal silica coatings by effective control of chemistry of particles along with process parameters.

Protective coatings

Surface chemistry

Binders

Association reactions

film stratification

particles

morphology regulation

Gelation

Sols

Silica

Silicon

Författare

Archana Samanta

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Romain Bordes

Chalmers, Kemi och kemiteknik, Tillämpad kemi

Soft Matter

1744-683X (ISSN) 1744-6848 (eISSN)

Vol. 16 27 6371-6378

SilCoTex: Hållbart smutsavvisande textilier (del 2)

Ludvig Svensson AB, 2017-12-01 -- 2020-01-30.

VINNOVA, 2017-12-01 -- 2020-01-30.

Ämneskategorier

Polymerkemi

Polymerteknologi

Materialkemi

Infrastruktur

Chalmers materialanalyslaboratorium

Styrkeområden

Materialvetenskap

DOI

10.1039/d0sm00317d

Mer information

Senast uppdaterat

2021-01-21