Thermoset epoxy adhesives are such a widely- and successfully-used set of products that you might question whether the technology needs further improvement. For example, in the production of high-performance composites, thermosetting epoxy adhesives offer an excellent cost:performance ratio. Nevertheless, ever more demanding requirements do necessitate improvements in areas such as the degree to which the adhesive shrinks upon curing, toughness and reworkability.
One relatively new class of additives and modifiers that looks to be capable of meeting these needs is the hyperbranched polymers (HBPs), large molecules with many functional endings to branches extending from a central chemical group. It was only around the beginning of this decade that the synthesis of such molecules became sufficiently economical to be considered for use in adhesives1, moving from an expensive and wasteful step-wise process used to produce true dendrimers to one- or two-step HBP bulk manufacturing2.[ Last edited by Pureland on 2012-12-16 at 16:50 ] |