Structure and rheology of aqueous poly(vinyl acetate) dispersions modified with montmorillonite
- 62 Downloads
It has been shown that the rheological properties and resistance to sedimentation of aqueous poly(vinyl acetate) (PVA) latexes, which are used for the preparation of coatings and adhesives, can be controlled by adding sodium montmorillonite (MMT). The adding of MMT initiates gelation of the PVA dispersions, which manifests itself as the appearance of the yield stress, thixotropy, and viscoelasticity. X-ray diffraction analysis of the complex dispersions and films based on them has shown a transition from exfoliated to intercalated clay tactoids with an increase in their content. In view of the complex composition of the PVA latexes, which contain a stabilizer (poly(vinyl alcohol)) and a plasticizer (dibutyl phthalate), the components that are predominantly intercalated into the MMT interplanar space, have been identified. The highest yield stress and rigidity of the structural network, which arises in a sample as a result of the joint coagulation of PVA and MMT particles, are observed upon the incorporation of 1.2 wt % MMT into the latex.
Unable to display preview. Download preview PDF.
- 1.Handbook of Industrial Water Soluble Polymers, Williams, P.A., Ed., Oxford: Blackwell, 2007.Google Scholar
- 2.Paints, Coatings and Solvents, Freitag, W. and Stoye, D., Eds., Weinheim: Wiley-VCH, 2008.Google Scholar
- 10.Kurenkov, V.V., Gerasin, V.A., Korolev, Yu.M., et al., Plast. Massy, 2015, nos. 7–8, p. 53.Google Scholar
- 13.Handbook of Clay Science, Bergaya, F. and Lagaly, G., Eds., Amsterdam: Elsevier, 2013, vol. 5.Google Scholar
- 14.Khailen, V., Dobavki dlya vodorastvorimykh lakokrasochnykh materialov (Dopants for Water-Soluble Paint and Varnish Materials), Moscow: Peint-Media, 2011.Google Scholar
- 26.Gordeeva, N.V., Tolmachev, I.A., Mashlyakovskii, L.N., and Vasil’ev, V.K., Izv. SPbGTI(TU), 2012, no. 14(40), p. 41.Google Scholar
- 36.Ngothai, Y. and Bhattacharya, S.N., Kolloidn. Zh., 1995, vol. 57, p. 220.Google Scholar