Excellent fracture toughness and hardness along with high transparency

Epoxy resins modified with nanoparticles exhibit a significantly higher flexural strength and hardness. Thanks to their excellent transparency and low viscosity, Nanopox® F and Albipox® F are extremely suitable for injection processes. The shrinkage is signifcantly reduced which enables Class A surfaces to be attained.

Product overview
Improvements to properties
How it works

Product overview [back]

Technical data (no specification)

Improvements to properties [back]

Modifying resins for fiber composites with about 10 % nanoparticles significantly enhances the mechanical properties of composites. Also, with increasing nanoparticle content the shrinkage is considerably reduced which enables a class-A surface to be attained. The CTE is also significantly reduced.

Albipox® F 080 or 081: If laminating or injection resins are modified with both copolymers (based on NBR) and nanoparticles, as realized in these two Albipox® types, the fracture toughness can be significantly increased compared to a modification with copolymers alone. Damage-tolerant systems, e.g. for ballistic applications (armor), with a superior property profile can be designed using this approach.

Figure 1 shows the flexural strength of a glass-fiber reinforced composite produced using VRTM (epoxy resin, anhydride-cured, 60 % glass fiber).

Figure 1: Flexural strength of a GFC depending on the nanoparticle content

Due to their small size and the absence of any larger aggregates, the nanoparticles can easily penetrate all fiber structures without compromising the impregnation by excessive viscosity, thereby enabling all the state-of-the-art process technologies like resin infusion, RTM, or resin injection. In addition to significantly improved mechanical properties (modulus, fracture toughness), the thermal expansion, shrinkage and electrical properties can also be improved.

How it works [back]

Nanopox® F products are colloidal silica sols in a resin matrix with surface-modified, spherically shaped silica nanoparticles having diameters below 50 nm and an extremely narrow particle size distribution (Fig. 2). Depending on the application, colloidal silica sols are used in corresponding epoxy resins or as ready-for-use products.

Figure 2:  Particle size distribution (Determined by SANS)

The spherical silica is distributed agglomerate-free in the resin matrix (Figure 3). This results in a very low viscosity of the dispersion with SiO2 contents of up to 40 wt%.

The nanoparticles are chemically synthesized from aqueous sodium silicate solution. In this unique process the binding agent is not damaged, in contrast to processes in which powdered fillers are dispersed with dissolvers or other equipment using high shear energy.

Figure 3: TEM – images of a cured Nanopox® sample with 5 % SiO2 nanoparticles

For further details, please contact our application specialists.