Effect of food additives on the microstructure, mechanical and watertransport properties of polyurethane films

AMALVY, JAVIER; ANBINDER, PABLO SEBASTIÁN; PERUZZO, PABLO

PROGRESS IN ORGANIC COATINGS

ELSEVIER SCIENCE SA

Lugar: Amsterdam; Año: 2016 vol. 101 p. 207 - 215

0300-9440

The objective of this work is to study the effects of common food preservatives (BHT, -tocopherol,EDTA-Na and potassium sorbate) on the morphological, mechanical and water transport properties ofpolyurethane (PU) as films or coatings. The influence of these additives on the polymer structure andthe polymer-additive interaction was evaluated by using SAXS, FTIR and DSC. The addition of additivesresults either in the formation of aggregates or modification of the polymer microstructure, dependingon the molecular size and nature of additive, i.e. number of polar groups, hydrophilicity, etc. The additionof BHT molecules seems to break the typical hard segments interactions in PUs, leading therefore to agood incorporation of the molecule in the polymer matrix, however, -tocopherol does not incorporateonto the PU matrix leading to an evident phase separation and not affecting therefore the microrangeof heterogeneities of the PU matrix. On the contrary, films doped with EDTA-Na or potassium sorbateshowed important changes in both soft and hard segments domains. As consequence, the water transportproperties were greatly affected by the incorporation of these food additives in the polymeric matrix.Films with potential antimicrobial or antioxidant activity were obtained, with a moderated decrease inthe mechanical properties.