Investigations into the Potential Abrasive Release of Nanomaterials due to Material Stress Conditions-Part A: Carbon Black Nano-Particulates in Plastic and Rubber Composites

Johannes Bott,Roland Franz

doi:10.3390/app9020214

Abstract

Plastic and rubber based composites containing carbon black (CB) were investigated for the potential to release CB nano-particulates under stress conditions into food simulants. Nanocomposites were exposed to thermal, chemical, and mechanical stress, followed by mechanical abrasion of their surface. Particle sensitive asymmetric flow field-flow fractionation (AF4) with multi angle laser light scattering (MALLS) detection was used to detect and quantify CB nano-particulates. This study demonstrates that, even under dynamic stress conditions, CB nano-particulates are not released from the plastic or rubber compounds into food. This study intends also to propose a general nano-release stress test protocol for plastic materials coming into contact with foodstuff.

Highlights

This article is the first in a series of two dealing with the investigation of the potential release of Nanomaterials (NMs) from nanocomposites under intense material stress conditions
Printex® 80 (Orion Engineered Carbons GmbH, Frankfurt am Main, Germany) and Printex® 85 (Orion Engineered Carbons GmbH, Frankfurt am Main, Germany) are typical grades used in plastic food packaging while N550 and N772 are widely used in rubber applications
The relevant AF4 elution times for carbon black (CB) were between t = 17 to 32 min, material and the sand into 96% ethanol, AF4/multi angle laser light scattering (MALLS) measurements were performed to detect potential but no signal other than that obtained from the sand blank was CB nano-particulates

Summary

Introduction

This article is the first in a series of two dealing with the investigation of the potential release of Nanomaterials (NMs) from nanocomposites under intense material stress conditions. An overview of the published literature can be found in the reviews by Duncan et al, Kuorwel et al and Störmer et al [6,7,8] Results from these migration studies are often inconsistent and in some cases even contradictory. Positive migration results were typically found either when direct contact of the food (simulant) with the NM was possible e.g., at cutting edges of the test specimen or when the surrounding matrix caused severe interactions with the nanocomposite e.g., due to the swelling or even degradation of the polymer. The occurrence of experimental errors or artefacts due to inadequate experimental designs might play a non-negligible role. This issue finds, insufficient consideration in the reported studies so far. A comprehensive experimental design (i.e., sample preparation, storage conditions of the samples, matrix interactions, and the choice of analytical method for the detection of NMs) should respect the

Methods

Results

Conclusion