98%
921
2 minutes
20
The EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) assessed the safety of the combined use of cyclooctene homopolymer (PCOE) and cobalt stearate (CoS) intended as a oxygen scavenger in the packaging of all kinds of food stored at room temperature or below for up to 6 months. The CoS is the oxidation catalyst and the PCOE is intentionally oxidised for the oxygen scavenging function. They are incorporated into a plastic layer that is intended to be either in direct or indirect contact with the food. The potential migration of cobalt and cyclooctene monomer were below their respective specific migration limit (SML). The potential migration of PCOE non-oxidised oligomeric low molecular weight fraction (LMWF) < 1,000 Da was estimated to be up to ■■■■■ The Panel concluded that this fraction does not raise concern for genotoxicity potential and that the no observed adverse effect level (NOAEL) derived from a subchronic toxicity study would ensure a margin of exposure large enough to not raise a safety concern. However, the Panel considered the analysis of the oxidised PCOE LMWF not sufficiently comprehensive, i.e. that additional oxidation products of different nature may be formed, and that the limit of detection corresponding to ca. ■■■■■ for individual substances is too high. The oxidised PCOE LMWF was not covered by the genotoxicity tests or the 90-day study on the PCOE oligomers. The assessment of the identified potential oxidised migrants was considered conclusive, but not that of the migrants having remained undetected. Therefore, the CEP Panel was not able to conclude on the safety of the proposed use of cyclooctene homopolymer and cobalt stearate together as active substances in a layer for scavenging oxygen, either in direct contact with the food or separated from the food by a passive layer of polymer.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC9219899 | PMC |
http://dx.doi.org/10.2903/j.efsa.2022.7364 | DOI Listing |
ACS Macro Lett
December 2022
Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455, United States.
Polymer blend compatibilization is an attractive solution for mechanical recycling of mixed plastic waste because it can result in tough blends. In this work, hydroxy-telechelic polyethylene (HOPEOH) reactive additives were used to compatibilize blends of polyethylene terephthalate (PET) and linear low-density polyethylene (LLDPE). HOPEOH additives were synthesized with molar masses of 1-20 kg/mol by ring-opening metathesis polymerization of cyclooctene followed by catalytic hydrogenation.
View Article and Find Full Text PDFThe EFSA Panel on Food Contact Materials, Enzymes and Processing Aids (CEP) assessed the safety of the combined use of cyclooctene homopolymer (PCOE) and cobalt stearate (CoS) intended as a oxygen scavenger in the packaging of all kinds of food stored at room temperature or below for up to 6 months. The CoS is the oxidation catalyst and the PCOE is intentionally oxidised for the oxygen scavenging function. They are incorporated into a plastic layer that is intended to be either in direct or indirect contact with the food.
View Article and Find Full Text PDFChemistry
November 2009
Molecular Design Institute and Department of Chemistry, New York University, 100 Washington Square East, New York, NY 10003, USA.
We report the synthesis of telechelic poly(norbornene) and poly(cyclooctene) homopolymers by ring-opening metathesis polymerization (ROMP) and their subsequent functionalization and block copolymer formation based on noncovalent interactions. Whereas all the poly(norbornene)s contain either a metal complex or a hydrogen-bonding moiety along the polymer side-chains, together with a single hydrogen-bonding-based molecular recognition moiety at one terminal end of the polymer chain. These homopolymers allow for the formation of side-chain-functionalized AB and ABA block copolymers through self-assembly.
View Article and Find Full Text PDFChemistry
May 2005
School of Chemistry and Biochemistry, Georgia Institute of Technology, 770 State Street NW, Atlanta, Georgia 30332-0400, USA.
A novel methodology for the formation of block copolymers has been developed that combines ring-opening metathesis polymerization (ROMP) with functional chain-transfer agents (CTAs) and self-assembly. Telechelic homopolymers of cyclooctene derivatives end-functionalized with hydrogen-bonding or metal-coordination sites are formed through the combination of ROMP with a corresponding functional CTA. These telechelic homopolymers are fashioned with a high control over molecular weight and without the need for post-polymerization procedures.
View Article and Find Full Text PDF