Case Study The Lifecycle of Conductive Plastics Based on Carbon Nanotubes - Safety of Nanomaterials along Their Lifecycle - page 402

TABLE 18.1
Areas for Detection and Identiication before Selective Quantiication Can Begin
Release Scenario
(Anticipated
Degradation
Mechanism)

Method to Simulate the
Lifecycle to Induce,
Detect, and Quantify
Release

Key Findings and Research
Needs

Morphology of Typical Released Fragments

Outdoor use
(UV degradation,
hydrolysis and weak
mechanical forces)

Accelerated dry or wet
weathering (ISO 4892;
International Organization
for Standardization 2011),
followed by immersion to
induce release into water,
detected by AUC, TEM,
EDX, LD, XPS

Nguyen et al. (2011) found a
collapsed layer of CNTs on
CNT-epoxy after UV
irradiation

Weathering tests are highly
standardized for plastics and
coatings, but the CNT network
formed on the composite
essentially eliminates the
release of CNT (Nguyen et al.
2011)
Methods to induce a release
during or after degradation are
exploratory, and miss selective
quantiication

500 nm

Hirth et al. (2013) performed
wet and dry weathering of
CNT-polyurethane followed
by immersion and shaking:
release of polymer-CNT
fragments, but free CNTs
only by sonication

200 nm