Effect of Surface Interactions on Adhesion of ElectrospunMeshes on Substrates.

Despitethe importance of adhesion between electrospun meshes andsubstrates, the knowledge on adhesion mechanism and the method toimprove the adhesion remain limited. Here, we precisely design themodel system based on electrospun poly(ethylene oxide) (PEO) meshesand the substrate of styrene-b-(ethylene-co-butylene)-b-styrene elastomer (SEBS),and quantitatively measure the adhesion with a weight method. Thesurfaces of SEBS with different roughness are obtained by castingSEBS solution on the smooth and rough glass slides, respectively.Then, the surfaces of casted SEBS are respectively grafted with PEGoligomers and long PEG chains much larger than the entanglement molecularweight by surface-initiated atom transfer radical polymerization (SI-ATRP)of poly(ethylene glycol) methyl ether methacrylate (PEGMA). The detachedsurfaces of SEBS and electrospun fibers after adhesion measurementsare analyzed by scanning electron microscopy (SEM). The adhesive forceand adhesion energy are found to lie in the range from 68 to 220 mNand from 12 to 46 mJ/m2, respectively, which are slightlyaffected by surface roughness of substrate but mainly determined bysurface interactions. Just as the chemical cross-linking induces thestrong adhesion, the chain entanglements on the interface lead tothe higher adhesion than those generated by hydrophilic–hydrophobicinteractions and hydrophilic interactions. The long grafted chainsand the enhanced temperature facilitate the chain entanglements, resultingin the strong adhesive force. This work sheds new light on the adhesionmechanism at molecular level, which may be helpful to improve theadhesion between the electrospun fibers and substrates in an environmentallyfriendly manner. [ABSTRACT FROM AUTHOR]