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Microgel Adhesives for Wet Cellulose: Measurements and Modeling
journal contribution
posted on 2012-03-27, 00:00 authored by Quan Wen, Robert PeltonNanostructured adhesive layers were prepared by adsorbing
and/or
grafting polyvinylamine (PVAm) onto carboxylated poly(N-isopropylacrylamide) (PNIPAM) microgels that were then assembled
between layers of wet oxidized cellulose. The wet delamination force
was measured as functions of PVAm content, PVAm molecular weight,
coverage (mass adhesive/joint area), and the distribution of carboxyl
groups in the PNIPAM microgels. The use of microgels is attractive
because simple physical adsorption onto the cellulose surfaces before
lamination gives much higher adhesive content and strength compared
to the corresponding adsorbed linear PVAm. Wet adhesion increased
with PVAm content in the microgels and the quantity of microgels in
the joint whereas adhesion was independent of PVAm molecular weight.
Physical adsorption of the PVAm onto/into the microgels gave the same
adhesion as covalently coupled PVAm. Finally, the roles of microgel
diameter, elasticity, and coverage were simulated by a simple peel
adhesion model in which the microgels were treated as ideal springs.