Applicable Base Polymer Properties
Epoxy adhesives are generally more resistant to a wide variety of liquid environments than other structural adhesives. However, they are generally considered to be very rigid systems, and as such they do not have exceptionally good impact or peel resistance unless modified with tougheners.
Nanopox products are epoxy resins containing amorphous silica nanoparticles with a spherical shape. Supplied as concentrates, they can be used like standard epoxy resins and blended with all standard epoxy resins. No special dispersing or mixing equipment is necessary. These particles have diameters around 20 nm and a very narrow particle size distribution. They are uniformly and agglomerate-free dispersed in the resin. As a consequence these resins have a comparable low viscosity, although they contain 40 wt% silica nanoparticles.
The above table presents typical two component epoxy adhesive formulations using SiO2 nanoparticle and ATBN toughening agents. Tensile shear strength and temperature resistance of these adhesives are relatively high. Peel strength is also high and does not decrease rapidly with lower temperatures. The durability of modified epoxies is satisfactory as measured by most long term moisture tests.
(Source: Evonik also A. J. Kinloch , et.al., “Toughening Structural Adhesives via Nano- and MicroPhase Inclusions”, The Journal of Adhesion, 79:8-9, 867-873, 2003)