3
Table 1
Compounding Formulation
Ingredients
Quantities (phr)
1
2
3
4
5
ENR
100
75
50
25
0
EVA
0
25
50
75
100
Ultrablend 600
5
5
5
5
5
Ultralube 220
1
1
1
1
1
TMQ
1
1
1
1
1
Untrasil (VN3)
a
30
30
30
30
30
Silquest A-171
b
1.8
1.8
1.8
1.8
1.8
A-20
30
30
30
30
30
TMPTMA
c
7.5
7.5
7.5
7.5
7.5
a
Silica,
b
Vinyl Silane,
c
Trimethylolpropane trimethacrylate
Mechanical testing
The dumbbell-shaped specimens of the TPVs with 2 mm thick were prepared by a thermoplastic injection
molding machine (Welltec Machinery Ltd., Hong Kong). Stress-strain behaviors of the TPVs based on ENR/EVA/PP
blends was performed at 25 ± 2°C at a crosshead speed of 500 mm/min according to ASTM D412. The instrument
used was Hounsfield Tensometer (model H 10 KS manufactured by the Hounsfield Test Equipment Co., Ltd., UK).
Aging properties of the TPVs were investigated according to ASTM D573.
Dynamic properties
Dynamic properties of the TPVs were characterized using a rotorless oscillating shear rheometer (RheoTech
MDPT, Cuyahoya Falls, USA) at 180°C. The oscillation frequency was set in the range of 1–30 Hz at a constant
strain of 3%. This was to assure that the test was in the range of linear viscoelasticity of the TPVs. The storage (G’)
and loss shear (G”) moduli, loss factor, tan
δ
=G”/G’ as well as the complex viscosity (i.e.,
η
*=3G*/
ω
=
η
”+ i
η
’) of the
TPVs were characterized.
Thermal properties
Thermal gravimetric analysis was undertaken using a gravimetric analyzer, PerkinElmer, STA6000 . The
samples were scanned from room temperature to 800°C at a heating rate 10°C/min under nitrogen atmosphere.
Morphological studies
Morphological studies were carried out using a Leo scanning electron microscope, model VP 1450,
manufactured by Leo (Cambridge, UK). The TPVs were cryogenic cracked in liquid nitrogen. This is to avoid any
possibility of phase deformation during cracking process. The PP phase was preferentially extracted by immersing the
