TITLE:
Effects of Solar UV Radiation on Materials Used in Agricultural Industry in Salta, Argentina: Study and Characterization
AUTHORS:
Carlos Cadena, Delicia Acosta
KEYWORDS:
Polyethylene Films, Photovoltaic Modules, Sunscreen Characterization, Degradation Effects, Stability
JOURNAL NAME:
Journal of Materials Science and Chemical Engineering,
Vol.2 No.4,
April
23,
2014
ABSTRACT: The current study presents the characterization
of three types of materials after exposure to solar UV radiation. The selection
of the materials is related to socio-economic aspects and rural activities in
the northwest of Argentina (a.k.a. NOA). The objective was to establish a time
parameter that allows estimating the durability of the materials according to
their use. One of the materials is used as a protective cover (polyethylene
film) of greenhouses, which are used for crop cultivation in the area. Another
material is used in photovoltaic modules (PVMs), which are used to supply energy
in isolated areas and the third material is sunscreen used by people that are
exposed to UV radiation during rural activities. Degradation or deterioration
of the materials was monitored using different spectroscopic assays: infrared
was used to detect any structural changes in the material, X-rays were used
for possible changes in the crystalline structure of the material, and spectral
transmittance as this property is likely to be affected by changes in the
structure of the material. The results showed that degradation of polyethylene
seems to be related to the diminution in transparency and the loss of
mechanical resistance with increasing exposure time. The decrease in
transparency of one of the layers of a PVM caused a considerable decrease in
the energy generated, whereas the sunscreens with a low sun protection factor
(SPF) rapidly lost their protective properties and changed their photostability
properties. Our results revealed a relationship between relative
transmittance loss and exposure timse, which allows estimating the stability of
different materials.