Produção de um filme sobreposto de PET/PVB com propriedades de contenção da radiação UV avaliado através da foto estabilidade de nifedpino

Abstract

The demand for new packaging materials with more speci c characteristics, such as transparency and containment of ultraviolet (UV) radiation, has been increasing in recent years. A great consumer of this technology is the pharmaceutical industry, as it needs materials with these characteristics. Aiming to reduce cost in the development of new materials, an alternative is the superimposed coating using polymers already known, and at least one of the polymers to be used has or can be added a speci c desired characteristic. It was evaluated through Dependent Time Density Functional Theory (DT-DFT) calculations the electronic transitions and their involved boundary molecular orbitals, in order to demonstrate the photophysical properties that provide stability to UV radiation in absorbers. A lm was developed with potential use as a packaging material capable of containing UV radiation in the tested range (190 to 400 nm), which presented complete protection under the conditions tested in the range from 377 to 388 nm, representing 94 to 97 % of the proposed range, in addition to maintaining the characteristics of a transparent material, with a small absorption in the visible region (VIS) up to 422 nm and average transmittance (T) in the same region of approximately 85 %. The lm remained stable after a cycle in a photostability chamber and when the effectiveness of the lm as a packaging material was evaluated through the decay of active matter from a solution of nifedipine (NIF), a decay for the lm of 0.27 mm of only 9.60 %, when compared to the control sample (coated with aluminum), that is, a high protection when compared to lms without absorbers. It can be inferred, therefore, that the PET/PVB overlay lm with UV absorbers is effcient in containing a large portion of UV radiation and maintains the characteristics of a transparent material.