Heat Aging Behavior of Novel Poly (Phenylene-Ether) Based Thermoplastic Elastomers

2008 ◽  
Vol 81 (2) ◽  
pp. 244-264 ◽  
Author(s):  
Samik Gupta ◽  
Radha Kamalakaran ◽  
Avdhut Maldikar ◽  
Ashok Menon ◽  
Anil K. Bhowmick

Abstract The heat aging performance of a series of novel poly (phenylene ether) (PPE) based thermoplastic elastomers (TPEs) from styrene-ethylene-butylene-styrene (SEBS), ethylene vinyl acetate (EVA) and PPE-polystyrene (PS), was studied. This quaternary blend showed superior heat aging performance due to the high Tg thermoplastic component (PPE). At 80 °C, different compositions of the quaternary blends were exposed for 500 hours. Effects of compositions, vinyl acetate (VA) content of EVA and different molecular weights (MW) of SEBS, on the mechanical properties upon heat aging were analyzed in detail. A representative composition (based on the mechanical properties) of the quaternary blend (SEBS/EVA/PPE-PS: 45/30/25) was exposed at different temperatures, i.e. 80 °C, 120 °C, 140 °C and 170 °C, for 2000 hours. Thermal degradation profiles of change in tensile strength and percent elongation at break due to thermal degradation of the blends were monitored and “half-life” temperature was estimated. Using the Arrhenius equation, the “lifetime” of the quaternary blend was predicted (100,000 hours at ∼131 °C). Change in functionalities due to chemical degradation was also monitored using Fourier Transform Infrared Spectroscopy (FTIR). As a consequence of degradation, the shift in Tg was observed by temperature modulated DSC (Differential Scanning Calorimeter). Detailed microstructural studies were done to establish the structure-property correlation, for degraded as well as pristine materials. The degradation mechanism was elucidated on the basis of morphology and structure studies of the blends.

2001 ◽  
Vol 74 (5) ◽  
pp. 815-833 ◽  
Author(s):  
S. Chattopadhyay ◽  
T. K. Chaki ◽  
Anil K. Bhowmick

Abstract New thermoplastic elastomers have been prepared from the blends of metallocene-based polyolefins (Engage) with low-density polyethylene (LDPE), and ethylene-vinyl acetate copolymers (EVA) of different grades with LDPE by electron beam modification. Structural changes of these blends with or without sensitizer in presence of irradiation have been evaluated by X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Scanning electron microscopy (SEM) in conjunction with atomic force microscopy (AFM) indicate the soft rubber domain in the continuous plastic matrix. Significant improvements of mechanical, dynamic mechanical and set properties have been obtained by electron beam modification, retaining its reprocessibility characteristics. Effects of ditrimethylol propane tetraacrylate (DTMPTA) as radiation sensitizer have also been evaluated from the mechanical, dynamic mechanical properties and reprocessibility.


1996 ◽  
Vol 47 (1) ◽  
pp. 247-258 ◽  
Author(s):  
M. L. Marín ◽  
A. Jiménez ◽  
J. López ◽  
J. Vilaplana

2019 ◽  
Vol 19 (11) ◽  
pp. 7476-7486
Author(s):  
Jinze Du ◽  
Hongyan Zeng ◽  
Enguo Zhou ◽  
Bo Feng ◽  
Chaorong Chen ◽  
...  

The microcapsule nanoparticles were prepared by in-situ copolymerization of hydrotalcites (MAH) with the polymer (MF, PF, PS and PU) monomers, respectively, where the MF-wrapped MAH (MAH@MF) had the best monodispersity. The composites of the microcapsules and EVA were prepared by incorporating the microcapsule nanoparticles into ethylene vinyl acetate (EVA), respectively. To further understand the intrinsic correlation between microcapsule fillers and EVA matrix, molecular dynamics (MD) simulation was introduced to qualitatively analyze the contribution of microcapsule fillers on improving compatibility and mechanical properties of the EVA matrix. The compatibility of microcapsule nanoparticles with EVA matrix were detected in sequence through SEM, DSC and tensile strength tests. And the combustion, thermal behavior and flame retardance were also characterized by TG analyses as well as LOI and UL-94 level. As a result, the MAH@MF filler had the best performances in improving the flame retardancy and mechanical properties among the microcapsule fillers, attributed to high compatibility of the MAH@MF and EVA matrix, which made uniform distribution of the MAH@MF filler due to the reciprocity of triazine functional ring with vinyl acetate linkages.


2018 ◽  
Vol 935 ◽  
pp. 79-83
Author(s):  
A.N. Volotskoy ◽  
Yuriy V. Yurkin ◽  
V.V. Avdonin

This research is devoted to the actual problem of the development of damping polymer materials which are effective in a wide range of temperatures and having satisfactory strength characteristics. There are many works devoted to the study of dynamic mechanical properties of filled composites, but most do not take into account the influence of plasticizer on the strength properties of the polymer, as they change its characteristics for the worse. In this respect, the study and comparison of the mechanical properties of the polymer base with the introduction of different types and concentrations of plasticizers is an urgent task. According to the received regularities it was possible to define the type, concentration and boundaries of the polarity of the plasticizer, which reduces the strength characteristics of ethylene-vinyl acetate to a lesser degree.


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