Property improvements of thermoplastic copolyester with a
multifunctional mixture/nanofiller by reactive extrusion
Eid M. Alosime ,
Grant A. Edwards,
Darren J. Martin
Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Queensland 4072, Australia
Nuclear Science Research Institute, King Abdulaziz City for Science and Technology, P.O. Box 6086, Riyadh 11442, Saudi
Correspondence to: E. Alosime (E-mail: firstname.lastname@example.org)
The approach of processing reactive functional nanofillers into thermoplastic copolyester (TPE-E) using reactive extrusion
(REX) has been explored. The mixing of a hydroxyl-bearing organo-fluoromica combined in toluene with a tetraglycidyl-4,4-
diamino-diphenylmethane (TGDDM) led to the intercalation of the TGDDM molecule into the interlayer space. Subsequent REX
work involved processing TPE-E with 0.3% (w/w) TGDDM and 2% (w/w) organoclay in a twin-screw extruder. It is demonstrated
that the effects of the modification route to control morphology on the nanoscale could be systematically investigated. The hard seg-
ment acted as a physical crosslink, imparting elastomeric properties on the soft segment. Increases seen in creep resistance and reduc-
tion in the water vapor transmission rate of TPE-E proved that the reactive organo-fluoromica was able to promote enhanced
dimensional stability and barrier properties of TPE-E.
2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46369.
crosslinking; extrusion; morphology
Received 19 September 2017; accepted 23 December 2017
Although polymer-layered silicate nanocomposites have now
been around for at least two decades, thermoplastic copolyester
(TPE-E) systems have not yet been sufficiently explored. TPE-Es
combine the chemical and material properties of chemically
crosslinked elastomers with engineered plastics, which are often
much easier and affordable to manufacture. These materials
consist of multiple domains, instead of the single domain found
in polyesters, and are commonly referred to as “hard” and
The “soft” blocks are responsible for the elasto-
meric character of the material, whereas the “hard” block con-
tains a fixed-chain network responsible for the reversibility of
the thermal network structure in such materials.
Of particular interest to researchers studying nanocomposite
materials are these thermocopolyesters, or synthetic rubbers,
consisting of hard polyester crystallites dispersed in a soft, flexi-
ble matrix. These materials combine the strength and processing
characteristics available to engineered plastics with the perfor-
mance abilities of thermoset elastomers, with the additional
benefit of attaining optimal properties without vulcanization, a
factor that can significantly reduce part cost.
Hytrel is a trade-
mark product of DuPont for TPE-E (copolyesters, COPEs) ther-
moplastic elastomer. The mechanical strength and durability of
the trademark enables it to be utilized for a range of operations
that are not limited to belts, bushings, and seals. Gears and
pump diaphragms are further applications in the locomotive
manufacturing firm, which need unique exhaustion resistance.
Additionally, its lack of permeability to nonpolar hydrocarbons
and refrigerate gases makes it an operational pipe for conveying
air for heating systems, cooking, and cooling.
Hytrel polymers have a great extent of permeability to polar ele-
ments like H
O, which restricts their use in parts for which
O impermeable or hydrothermal stability are needed.
combination of reactive nanofillers is perceived to be an encour-
aging approach to address this restriction. The addition of the 2
wt % high-aspect ratio organoclay has been discussed in our
previous article; in particular, it showed statistically improved
tensile strength, tear resistance, creep resistance, and water-
vapor permeation barrier enhancement.
However, to the best
of our knowledge, the reactive extrusion (REX) of TPE-E and
tetra-glycidyl ether of diphenyl diamino methane (TGDDM)
has scarcely been reported. Kuramochi et al.
studied the REX
of crosslinked TPE-E with TGDDM using a single-screw
extruder and reported that the ultimate strength and compres-
sion set improved. Until now, TGDDM was applied to increase
the viscosity of poly(butylene terephthalate) (PBT) and enhance
the interfacial adhesion between the PBT matrix and elastomer.
Because of its relatively low molecular mass, TGDDM might, in
concept, be capable of drifting between phases in TPE-E and
2018 Wiley Periodicals, Inc.
J. APPL. POLYM. SCI. 2018, DOI: 10.1002/APP.46369
46369 (1 of 12)