Effects of different drying methods on the microstructure and thermal oxidative aging resistance of natural rubber

2012 ◽  
Vol 126 (6) ◽  
pp. 1808-1813 ◽  
Author(s):  
Chen Mei ◽  
Wang Yong-Zhou ◽  
Lu Guang ◽  
Wang Xiao-Ping
Keyword(s):  
Natural Rubber ◽  
Drying Methods ◽  
Oxidative Aging ◽  
Aging Resistance ◽  
Thermal Oxidative Aging

Study on Aging Resistance Properties of Natural Rubber Dried by Microwave

2013 ◽  
Vol 706-708 ◽  
pp. 266-269
Author(s):  
Yong Zhou Wang ◽  
Fu Quan Zhang ◽  
Mao Fang Huang ◽  
Mei Chen ◽  
Hong Xing Gui ◽  
...  
Keyword(s):  
Natural Rubber ◽  
Oxidative Degradation ◽  
Rate Of Change ◽  
Thermal Oxidative Degradation ◽  
Oxidative Aging ◽  
Degradation Temperature ◽  
Hot Air ◽  
Aging Resistance ◽  
Before And After ◽  
Thermal Oxidative Aging

In this work, thermogravimetry (TG) and Wallace plastometer were used to study the thermal-oxidative aging resistance properties of natural rubber (NR) dried by microwave and hot-air. Showed from the results, thermal degradation temperature, primary thermal-oxidative degradation temperature, the value of P0, PRI and VR for NR dried by microwave were higher than those of NR dried by hot-air; the thermal-oxidative aging resistance properties of NR vulcanizes dried by microwave improved significantly, and the rate of change for elongation at break (-26.76%) and tensile strength (-38.6%) of NR vulcanizes dried by microwave before and after aging were apparently higher than those of NR vulcanizes dried by hot-air, which were (-60.29%) and (-82.11), respectively.

Thermal-Oxidative Aging Resistance and Water Absorption of Natural Rubber Latex/Methyl Methacrylate-Grafted-Natural Rubber Latex Blends

2012 ◽  
Vol 550-553 ◽  
pp. 1755-1758
Author(s):  
Guang Lu ◽  
He Ping Yu
Keyword(s):  
Natural Rubber ◽  
Methyl Methacrylate ◽  
Water Absorption ◽  
Natural Rubber Latex ◽  
Latex Film ◽  
Rubber Latex ◽  
Oxidative Aging ◽  
Aging Resistance ◽  
Before And After ◽  
Thermal Oxidative Aging

Abstract. The natural rubber latex (NRL) concentrate was mixed with 10～50 parts per hundred rubber (phr) of methyl methacrylate-grafted-natural rubber latex having a methyl methacrylate content of 49% (MGL49), prevulcanized, and then cast to obtain prevulcanized NRL/MGL49 films. The leached films of prevulcanized NRL/MGL49 were aged in an hot-air oven for comparison of the mechanical properties before and after aging, whereas the thermal decomposition of these films in an atmosphere of air was carried out in a thermo-gravimetric analyzer, and the films were also immersed into water to obtain water absorption. Results showed that the incorporation of MGL49 improved the thermal-oxidative aging resistance of natural rubber latex film when the MGL49 content was less than 50 phr, the water absorption increased with the increment of MGL49 content, and the NRL/MGL49 film containing 10phr of MGL 49 has a best thermal-oxidative stability and highest water absorption also.

Synthesis of sulphonic lanthanum complex based on C-methylcalix[4]resorcinarene and its thermo-oxidative aging resistance for natural rubber

2017 ◽  
Vol 46 (6) ◽  
pp. 251-257
Author(s):  
Hongqiang Li ◽  
Yong Zhong ◽  
Lin Zhang ◽  
Wenjian Wu ◽  
Xuejun Lai ◽  
...  
Keyword(s):  
Natural Rubber ◽  
Oxidative Aging ◽  
Aging Resistance ◽  
Lanthanum Complex

Investigation of physical properties and morphology of compatibilized EPDM/EVA blends

2017 ◽  
Vol 31 (3) ◽  
pp. 376-391 ◽  
Author(s):  
Aman I Khalaf ◽  
Azza A Ward ◽  
Nehad N Rozik
Keyword(s):  
Vinyl Acetate ◽  
Ethylene Vinyl Acetate ◽  
Elongation At Break ◽  
Oxidative Aging ◽  
Itaconic Anhydride ◽  
Aging Resistance ◽  
Before And After ◽  
Time Periods ◽  
Poly Ethylene ◽  
Thermal Oxidative Aging

The main aim is to investigate the effect of adding of 5% hydrolyzed poly (ethylene-co-vinyl acetate) (EVAOH), itaconic anhydride (naturally obtained during fermentation of sugars (It.anhydride)), and mercapto-modified ethylene-co-vinyl acetate (EVASH) as compatibilizers on the mechanical properties before and after thermal oxidative aging at 90°C for different time periods up to 7 days, electrical properties, and morphology of ethylene propylene diene monomer/ethylene vinyl acetate (EPDM/EVA) blends of different compositions (75/25, 60/40, 50/50, and 25/75, respectively). Stress at yield, tensile strength, and elongation at break of EPDM/EVA were improved markedly by the addition of 5% compatibilizers (EVAOH, It.anhydride, and EVASH). The micrographs of fractured surfaces obtained from the scanning electron microscope demonstrated further the enhancement of compatibility between EPDM and EVA by the addition of reactive compatibilizers. Further, the blends permittivity ε′ and dielectric loss ε″ have been measured at specific temperatures. The dielectric properties revealed that It.anhydride and EVASH/EPDM/EVA compositions are promising materials for insulation purposes. Finally, aging resistance was improved by the use of compatibilizers.

Thermo-oxidative aging resistance and mechanism of a macromolecular hindered phenol antioxidant for natural rubber

2017 ◽  
Vol 50 (4) ◽  
pp. 372-387
Author(s):  
Wenjian Wu ◽  
Hongqiang Li ◽  
Shuyan Yang ◽  
Xuejun Lai ◽  
Hongbo Fan ◽  
...  
Keyword(s):  
Natural Rubber ◽  
Polymer Materials ◽  
Oxidation Induction Time ◽  
Elongation At Break ◽  
Oxidative Aging ◽  
Aging Resistance ◽  
New Strategy ◽  
Hindered Phenol ◽  
Polymer Aging ◽  
Very High

Macromolecular antioxidant due to its low physical loss, high thermal stability, and good compatibility has been considered to be a promising candidate to inhibit polymer aging. In this study, thermo-oxidative aging resistance and antioxidative mechanism of a macromolecular hindered phenol antioxidant, namely, polyhydroxylated polybutadiene containing thioether binding 2, 2′-thiobis (4-methyl-6-tert-butylphenol) (PHPBT-b-TPH) for natural rubber (NR) vulcanizate was studied in detail by oxidation induction time and accelerated thermal aging tests. The results showed that the antioxidative efficiency of PHPBT-b-TPH was very high. When the amount of PHPBT-b-TPH was only 1 phr, the NR vulcanizate could exhibit excellent thermo-oxidative aging resistance, obviously higher than that of NR vulcanizate with low-molecular-weight antioxidant TPH. After aged at 100°C for 168 h, the retentions of tensile strength and elongation at break of NR vulcanizate with PHPBT-b-TPH were 43.6% and 58.6%, respectively. However, those of NR vulcanizate with TPH were 35.6% and 54.5%. In addition, it was found that both thioether and urethane groups in PHPBT-b-TPH had antioxidative ability and had synergistic effect with hindered phenol. Through our findings, new strategy to design and synthesize the macromolecular antioxidant with multi-antioxidative groups for rubber materials and other polymer materials could be developed.

Performance Evaluation of SBS Modified Bituminous Roofing Membrane Containing Layered Double Hydroxides

2014 ◽  
Vol 599 ◽  
pp. 203-207
Author(s):  
Song Xu ◽  
Wei Dan ◽  
Wen Zu Li ◽  
Jian Ying Yu
Keyword(s):  
Layered Double Hydroxides ◽  
Melt Blending ◽  
Modified Bitumen ◽  
Oxidative Aging ◽  
Aging Resistance ◽  
Waterproofing Membrane ◽  
Low Temperature Flexibility ◽  
Thermal Oxidative Aging ◽  
Double Hydroxides ◽  
Over Time

Layered double hydroxides (LDHs)/SBS modified bitumens used for waterproofing membrane were prepared by melt blending using various contents of SBS and LDHs. Effects of the LDHs on physical properties and thermal oxidative aging performance of modified bitumen were investigated. The results show that softening point and low temperature flexibility of LDHs/SBS modified bitumen are increased simultaneously with the rise of SBS content, while they are little affected by the change of LDHs content. The thermal oxidative aging resistance of SBS modified bitumen is gradually improved with increasing LDHs content. In addition, the aging rate of SBS modified bitumen with LDHs are evidently lower than that without LDHs over time, which indicates that LDHs improve the ability of SBS modified bitumen to resist the thermal oxidative aging effectively.

Sign in / Sign up

Export Citation Format

Share Document