MoS₂ nanoplatelet fillers for enhancement of the properties of waterborne pressure-sensitive adhesives.

Nanocomposite pressure-sensitive adhesives (PSAs) composed of polyurethane (PU)/(meth)acrylates reinforced with MoS2 nanoplatelets were prepared by blending aqueous dispersions. MoS2 crystals were exfoliated by sonication in water in the presence of poly(vinylpyrrolidone) (PVP, molecular weight of 10,000 g mol(-1)) to prepare an aqueous dispersion. Waterborne colloidal polymer particles (latex) were synthesized by miniemulsion photopolymerization in a continuous tubular reactor. The adhesive and mechanical properties from the resulting nanocomposite films were determined as the MoS2 fraction was increased. A superior balance of viscoelastic properties was achieved with 0.25 wt % loading of the MoS2 nanoplatelets, leading to a tack adhesion energy that was three times greater than that for the original PSA.