Stabilizing copolymer, adhesive composition, method of making the same, and article including the same

A method of making an adhesive composition, the method comprising the sequential steps:

• I) providing a first polymerizable composition comprising:
• at least one alkyl (meth)acrylate;
• at least one optional first polar free-radically polymerizable monomer;
• and
• at least one first free-radical polymerization initiator;
• II) forming a syrup composition by partially polymerizing the first polymerizable composition, wherein the syrup composition comprises:
• 1 to 20 weight percent of a solute polymer based on the total weight of the syrup composition, the solute polymer having a weight average molecular weight of at least 100000 daltons;
• and
• 80 to 99 weight percent of solvent monomers based on the total weight of the syrup composition, the solvent monomers comprising:
• the at least one alkyl (meth)acrylate;
• and
• the at least one optional first polar free-radically polymerizable monomer;
• and
• III) preparing a second polymerizable composition comprising:
• the syrup composition;
• at least one optional second polar free-radically polymerizable monomer, wherein the at least one optional second polar free-radically polymerizable monomer and the at least one optional first polar free-radically polymerizable monomer may be the same or different;
• at least one stabilizing copolymer comprising:
• a) 20 to 90 weight percent of at least one first divalent monomer unit represented by:
• or
• wherein:
• each R1 is independently H or methyl;
• each R2 is independently methyl or ethyl;
• each R3 is independently methylene, ethylene, or propylene;
• each R4 is independently methyl, ethyl, propyl, or butyl;
• each n is independently an integer from 2 to 65;
• and
• b) 10 to 80 weight percent of at least one second divalent monomer unit represented by
• wherein:
• each R6 independently represents a poly(alkyleneoxy) group, wherein the poly(alkyleneoxy) group comprises ethyleneoxy groups;
• and
• each X independently represents H or alkyl having 1 to 6 carbon atoms;
• at least one crosslinking agent;
• at least one second free-radical initiator;
• IV) frothing the second polymerizable composition to provide a frothed polymerizable composition;
• and
• V) polymerizing the frothed polymerizable composition to form the adhesive composition.

A stabilizing copolymer comprising:

• a) 20 to 90 weight percent of at least one first divalent monomer unit represented by:
• wherein:
• each R1 is independently H or methyl;
• each R3 is independently methylene, ethylene, or propylene;
• each R4 is independently methyl, ethyl, propyl, or butyl;
• each n is independently an integer from 2 to 65;
• and
• b) 10 to 80 weight percent of at least one second divalent monomer unit represented by
• wherein:
• each R6 independently represents a poly(alkyleneoxy) group, wherein the poly(alkyleneoxy) group comprises ethyleneoxy groups;
• and
• each X independently represents H or alkyl having 1 to 6 carbon atoms.