Multi-Walled Carbon Nanotubes (MWCNT), synthetic graphite in tubular shape

Nanomaterial agglomeration / aggregation

Administrative data

Endpoint:

nanomaterial agglomeration/aggregation

Remarks:

NC7000 4.28.1 Nanocyl, Devoille 2019 agglomerate size, rel 1

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other:

Version / remarks:

NF CEN ISO 19749

Deviations:

not specified

Principles of method if other than guideline:

The measurand was the minimum Ferret diameter of the agglomerate/aggregates.

GLP compliance:

no

Type of method:

scanning electron microscopy

Details on methods and data evaluation:

Results were obtained according to NFCEN ISO 19749 with a relative error of 5 % and a probability of 95%.

Sampling:

2 series of 350 agglomerates/aggregates were analized.

Test material

Test material information

Constituent 1

Reference substance name:

carbon

EC Number:

936-414-1

Molecular formula:

C

IUPAC Name:

carbon

Test material form:

solid: nanoform, no surface treatment

Details on test material:

- State of aggregation: entangled nanotubes, as described in Section 4.28.1
- Particle size distribution: entangled nanotubes, as described in Section 1.2, 1.4. and 4.28.1.
- Mass median aerodynamic diameter (MMAD): As the product tends to agglomerate this depends on the testing conditions. See Section 4.
- Geometric standard deviation (GSD): Depends on the testing conditions. See Section 4.
- Shape of particles:nanotubes, aspect ratio of ~163:1
- Surface area of particles: 250 - 300 m²/g (BET)
- Crystal structure: graphite.
- Coating: None
- Surface properties: No functionalization intended.
- Density: May vary depending on the batch number. Available information is reported in the Confidential details on test material for each study.
- Moisture content: Not determined. May vary depending on the batch number.
- Residual solvent: Not applicable.
- Activation: Not applicable.
- Stabilisation: Not applicable.
- Other: Not applicable.

Specific details on test material used for the study:

Nanocyl NC7000 was tested as supplied, in dry powder form.

Data gathering

Instruments:

Scanning Electron Microscope Zeiss Ultra-Plus with secundary detector In-Lens.

Calibration:

No data available.

Reproducibility:

2 series of 350 agglomerates/aggregates were analized.

Results and discussion

Agglomerate / aggregate diameter

Key result

Mean diameter:

41.2 μm

St. dev.:

1.3 μm

Medium:

Dry powder.

Agglomerate / aggregate size

Key result

Percentile:

D50

Mean:

30.1 μm

St. dev.:

1.5 μm

Medium:

Dry powder.

Applicant's summary and conclusion

Conclusions:

The agglomerates/aggregates in the product as supplied in dry powder form have diverse shapes and sizes.
In this study, 789 agglomerates/agrégates were considered according to the norm CEN ISO 19749.
Mean agglomerate/aggregate size was 41,2 μm ± 1,3 μm while median agglomerate/aggregate size was 30,1 μm ± 1,5 μm.

Executive summary:

Mean minimim Feret diameter of the agglomerates/aggregates is 41,2 μm ± 1,3 μm.

Median minimim Feret diameter of the agglomerates/aggregates is 30,1 μm ± 1,5 μm.