Tacky microspheres having pendant hydrophilic polymeric or oligomeric moieties
AssigneeMinnesota Mining and Manufacturing Company
InventorsJoaquin Delgado, Richard J. Goetz, Spencer F. Silver
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Abstract
The invention provides inherently tacky, polymeric, organic, solvent-insoluble, solvent dispersible, elastomeric, pressure sensitive adhesive microspheres having pendant hydrophilic polymeric or oligomeric moieties having a degree of polymerization greater than or equal to 2. The microspheres which are sterically stabilized can offer enhanced stability against coagulation caused by alkali, alkali salts, polyelectrolytes and repeated freeze/thaw cycles. The present invention also provides pressure-sensitive adhesives comprising these microspheres including aerosol spray PSAs, coated sheet materials prepared therefrom, and method of making the microspheres.
Claims41
Inherently tacky, polymeric, organic, solvent-insoluble, solvent dispersible, elastomeric, pressure sensitive adhesive microspheres having pendant hydrophilic polymeric or oligomeric moieties having a degree of polymerization greater than or equal to 2;
- wherein the microspheres once dried will disperse in an organic liquid and wherein the microspheres have diameters of about 1 to about 300 micrometers.
Inherently tacky, polymeric, solvent-insoluble, solvent dispersible elastomeric microspheres having pendant hydrophilic polymeric or oligomeric moieties comprising:
- 100 parts by weight of the polymerization product of:
- (a) at least about 30 parts by weight of at least one free radically polymerizable monomer selected from the group consisting of vinyl esters, alkyl acrylate esters, alkyl methacrylate esters, and mixtures thereof, wherein a polymer prepared from said monomers would have a Tg of less than about -10.degree. C.;
- (b) about 0 to about 30 parts by weight of at least one polar monomer copolymerizable with the monomer of element (a);
- and
- (c) about 0.5 to about 40 parts by weight of at least one hydrophilic component selected from the group consisting of free radically reactive hydrophilic oligomers and polymers having a degree of polymerization greater than or equal to 2, functionalized derivatives thereof, and mixtures thereof, wherein the microspheres once dried will disperse in an organic liquid and wherein the microspheres have diameters in the range of about 1 to about 300 micrometers.
A sheet material having coated there on at least a portion thereof the pressure-sensitive adhesive microspheres of claim.
Dependencies are inferred from the claim text.