Migration of monomers from liquid crystalline poly(p-hydroxybenzoic acid-co-2-hydroxy-6-naphthoic acid).
Liquid-crystalline co-polyesters (e.g. a random copolyester based on p-hydroxybenzoic acid (HBA) and 2-hydroxy-6-naphthoic acid (HNA) known as Vectra A950) offer good barrier properties, but for food-contact use require overall and specific migration testing. For Vectra A950 films, the highest overall migration level obtained was 2.3 mg kg(-1) in olive oil (10 days at 40 degrees C) well below the EC limit of 60 mg kg(-1). The highest specific migration for p-hydroxybenzoic acid was 15.2 microg dm(-2) in olive oil (2h at 175 degrees C). For 2-hydroxy-6-naphthoic acid, the highest value obtained was 4.3 microg dm(-2) in 10% ethanol (4h at 100 degrees C), although it was not on the EC positive and cannot yet be used for food-contact materials. At conditions considered as severe, the estimated daily intake for p-hydroxybenzoic acid was calculated as 11.9 microg/person day(-1) and for 2-hydroxy-6-naphthoic acid it was 5.3 microg/person day(-1). The results exceed the threshold of regulation of 1.5 microg/person day(-1).
Flodberg
G
G
The Foundation Packforsk, The Institute for Packaging and Distribution, Box 9, SE-164 93 Kista, Sweden. geede@polymer.kth.se
Höjvall
L
L
Hedenqvist
M S
MS
Gedde
U W
UW
D002849:Chromatography, Gas; D002851:Chromatography, High Pressure Liquid; D005506:Food Contamination / Q000032:analysis*; D018857:Food Packaging; D006801:Humans; D000069463:Olive Oil; D010938:Plant Oils / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*
D000069463:Olive Oil; D010938:Plant Oils; D011108:Polymers; C422409:liquid crystal polymer