Aperçu du fichier PDF 01694243-2e2015-2e1105123.pdf - page 3/16

Page 1 2 34516

Aperçu texte

Downloaded by [University of Tokyo] at 00:24 17 November 2015


  M. F. Zaki et al.

branches of applied science such as radiation protection, dosimetry, earth science, and
radiation biology.[7–10] On the other hand, poly (butylene terephthalate), also known as
PBT, has excellent thermal and mechanical properties and high chemical resistance. Blend
of these two polymeric materials give them superior mechanical and optical properties even
if some of them possess undesirable properties.[11–13] Makroblend is distinct by a good
chemical resistance, good paint ability, low moisture uptake, high toughness even at low
temperatures, and reduced susceptibility to stress cracking.[14–17] PC/PBT polymer blend
is used in different industrial applications such as electrical engineering/microelectronics,
automotive engineering, photonic crystal applications, sports and leisure, and lighting technology.[18–22] Modification of polymeric materials by radiation is a promising technique
for the production of new polymeric materials that can be used in different applications.
Study of radiation interaction with polymeric material has a special importance; it is a
selective phenomenon.
Irradiation of polymers with low and high energy transfer can play an important role to
modify both physical and chemical properties of polymeric materials. Ion beam irradiation
(as a high linear energy transfer radiation) and electron beam and gamma irradiation (as a
low linear energy transfer radiation) have been used to modify the properties of polymers
for high-technology applications.[23] Furthermore, the interaction of ionizing radiation
with polymers causes modifications of the polymer structure, which lead to changes in its
physical, chemical, structural, mechanical, optical, and surface properties.[24] These modifications of polymer properties by radiation have been due to crosslinking, scissioning, formation of carbon clusters [25], and creation of volatile species during the irradiation process.
More than that, during gamma irradiation of polymeric materials, chemical bonds may be
disrupted and leads to release of hydrogen atoms in the form of hydrogen molecules, which
causes changes in the properties of the irradiated polymers. In general, theses alterations in
irradiated polymers are depend on the irradiation conditions such as the type of radiation,
fluence/dose, the energy, linear energy transfer, and the nature of polymeric material.[26]
In the present work, the alterations of optical, structural, chemical, and surface properties
of PC/PBT have been studied as a result of gamma irradiation. The characterizations of
PC/PBT samples were carried out by using UV–vis spectroscopy, X-ray diffraction (XRD),
Fourier transform infrared (FTIR) spectroscopy as well as surface wettability by contact
angle measurements. In addition, the principle objective of this study aimed to modify the
properties of PC/PBT through gamma irradiation induced modifications on a molecular
level. For more informative from a scientific point of view of this study, an attempt has been
made to correlate the obtained results with reported data.

2.  Experimental details
PC/PBT composite used in this study was manufactured by Bayer Material Science Company,
Leverkusen, Germany. The polymeric blend material samples have a thickness of 1.0 mm
and dimension 2 × 2 cm2. The chemical structure of PC/PBT is as [27]: