scholarly journals Synthesis of Low Temperature Resistant Hydrogenated Nitrile Rubber Based on Esterification Reaction

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4096
Author(s):  
Lin Wang ◽  
Yanqiang Ni ◽  
Xin Qi ◽  
Liqun Zhang ◽  
Dongmei Yue
Keyword(s):  
Low Temperature ◽  
Nitrile Rubber ◽  
Petroleum Exploration ◽  
Esterification Reaction ◽  
Grafted Polymers ◽  
Scanning Calorimetry ◽  
Temperature Resistance ◽  
Molecular Weights ◽  
Cold Environments ◽  
Low Temperature Resistance

Hydrogenated Nitrile Rubber (HNBR) is widely used in aerospace, petroleum exploration and other fields because of its excellent performances. However, there remains a challenge of balancing the oil resistance and the low temperature resistance for HNBR. In this work, a series of grafted carboxyl nitrile rubber (XNBR) was prepared by the esterification reaction between active functional groups (–COOH) of XNBR and alkanols of different molecular chain lengths (C8H17OH, C12H25OH, C16H33OH, C18H37OH) or Methoxypolyethylene glycols (MPEG) of different molecular weights (Mn = 350, 750, 1000). The structure and low temperature resistance of as-obtained grafted polymers were characterized by Fourier Transform Infrared (FTIR), 1H-NMR and Differential scanning calorimetry (DSC). It was found that the glass transition temperatures (Tg) of grafted XNBR were significantly decreased. MPEG grafted polymers with better low temperature resistance were then selected for hydrogenation. As-prepared hydrogenated XNBR grafted with MPEG-1000 (HXNBR-g-1000) showed the lowest Tg of −29.8 °C and the best low temperature resistance. This work provides a novel and simple preparation method for low temperature resistant HNBR, which might be used potentially in extremely cold environments.

Study on Application of the Blends of Nitrile Rubber with Acrylate Rubber in the Coat-Metal Sealing Gasket

2011 ◽  
Vol 393-395 ◽  
pp. 1438-1442 ◽  
Author(s):  
Zu Min Qiu ◽  
Chao Yan Qin ◽  
Jun Ming Qiu
Keyword(s):  
Mechanical Properties ◽  
Low Temperature ◽  
Heat Resistance ◽  
Nitrile Rubber ◽  
Temperature Resistance ◽  
Oil Resistance ◽  
Comprehensive Properties ◽  
The Cost ◽  
Low Temperature Resistance

This paper discussed the effect of different blending ratio with BNR and ACM on the mechanical properties, heat resistance, low temperature resistance and oil resistance of coat-metal sealing gasket. The result showed that the comprehensive properties of the NBR/ACM blends at the ratio of 85/15 were preferable to the NBR and ACM, the low temperature resistance and oil resistance of NBR are taken into account. The cost of the blends were lower than the ACM. The blends can be used for coat-metal sealing gasket instead of NBR.

A Study of Mechanical, Oil Resistance, and Low Temperature Resistance of NBR Vulcanizates

2016 ◽  
Vol 703 ◽  
pp. 165-171 ◽  
Author(s):  
Kwan Ho Seo ◽  
Gi Myeong Nam ◽  
Dong Gug Kang ◽  
Gi Hong Kim ◽  
Do Young Kim ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Low Temperature ◽  
Testing Machine ◽  
Butadiene Rubber ◽  
Scanning Calorimetry ◽  
Temperature Resistance ◽  
Oil Resistance ◽  
Universal Testing ◽  
Optimum Formulation ◽  
Low Temperature Resistance

In this study, mechanical properties, oil resistance of Nitrile Butadiene Rubber (NBR) as material of an automotive were investigated at low temperature conditions. In order to find the optimum formulation used various grades of NBR with different contents of Acrylonitrile (ACN) such as NT1846F, DN407, B7150, B6240 and N215SL. The mechanical properties, oil and low temperature resistance of NBR were measured using moving die rheometer, durometer, universal testing machine, differential scanning calorimetry, and Gehman tester. The hardness was increased with an increased ACN contents. The low temperature resistance, and degree of swelling were increased that decreased ACN contents have lower Tg, lower value of Gehaman test.

Highly Tough, Freezing-Tolerant, Healable and Thermoplastic Starch/Poly(vinyl alcohol) Organohydrogels for Flexible Electronic Devices

2021 ◽  
Author(s):  
Jing Lu ◽  
Jianfeng Gu ◽  
Oudong Hu ◽  
Yunhan Fu ◽  
Dezhan Ye ◽  
...  
Keyword(s):  
Low Temperature ◽  
Electronic Devices ◽  
Future Generation ◽  
Thermoplastic Starch ◽  
Poly Vinyl Alcohol ◽  
Temperature Resistance ◽  
Large Application ◽  
Conductive Hydrogels ◽  
Low Temperature Resistance ◽  
Application Prospects

The conductive hydrogels have found large application prospects in fabricating flexible multifunctional electronic devices for future-generation wearable human-machine interactions. However, the inferior mechanical strength, low temperature resistance, and non-recyclability induced...

Photosynthesis and antioxidant metabolism modulate the low-temperature resistance of seed germination in maize

2021 ◽  
Author(s):  
Aiju Meng ◽  
Daxing Wen ◽  
Chunqing Zhang
Keyword(s):  
Seed Germination ◽  
Low Temperature ◽  
Temperature Stress ◽  
Seedling Growth ◽  
Low Temperature Stress ◽  
Maize Seed ◽  
Down Regulation ◽  
Antioxidant Metabolism ◽  
Temperature Resistance ◽  
Low Temperature Resistance

Spring maize is usually subjected to low-temperature stress during seed germination, which retards seedling growth even if under a suitable temperature. However, the mechanism underlying maize seed germination under low-temperature stress modulating seedling growth after being transferred to normal temperature is still ambiguous. In this study, we used two maize inbred lines with different low-temperature resistance (SM and RM) to investigate the mechanism. The results showed that the SM line had higher lipid peroxidation and lower total antioxidant capacity and germination percentage than the RM line under low-temperature stress, which indicated that the SM line was more vulnerable to low-temperature stress. Further transcriptome analysis revealed that seed germination under low-temperature stress caused down-regulation of photosynthesis related gene ontology (GO) terms in two lines. Moreover, the SM line displayed down-regulation of ribosome and superoxide dismutase (SOD) related genes, whereas genes involved in SOD and vitamin B6 were up-regulated in the RM line. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis revealed that photosynthesis and antioxidant metabolism related pathways played important roles in seed germination in response to low-temperature stress, and the photosynthetic system displayed a higher damage degree in the SM line. Both qRT-PCR and physiological characteristics experiments showed similar results with transcriptome data. Taken together, we propose a model for maize seed germination in response to low-temperature stress.

scholarly journals COMPARATIVE ANALYSIS OF LOW TEMPERATURE RESISTANCE FOR NANOCARBON AND OTHER BITUMENS

2020 ◽  
Vol 5 (443) ◽  
pp. 89-96
Author(s):  
Zhurinov M.Zh., ◽  
◽  
Teltayev B.B., ◽  
Kalybay A.A., ◽  
Rossi C.O., ◽  
...  
Keyword(s):  
Comparative Analysis ◽  
Low Temperature ◽  
Polyphosphoric Acid ◽  
Crumb Rubber ◽  
Petrochemical Plant ◽  
Short Term ◽  
Temperature Resistance ◽  
Coal Rock ◽  
Low Temperature Resistance

A comparative analysis of the low temperature resistance for a nanocarbon bitumen and other 30 neat and modified bitumens has been performed in the work. The stiffness at the temperatures of -24°С, -30°С and -36°С under technical system Superpave has been accepted as an indicator of low temperature resistance of the bitumens. The stiffness of the bitumens has been determined on a bending beam rheometer (standard ASTM D 6648-08). Before testing the bitumens have been subjected to the double artificial aging: short-term aging – under standard AASHTO Т 240-13 and long-term aging – under standard ASTM D 6521-08. The nanocarbon bitumen has been prepared in the laboratory of the Kazakhstan Highway Research Institute (KazdorNII) with the use of a road bitumen of the grade BND 70/100 produced by the Pavlodar petrochemical plant (PNHZ) and a nanocarbon powder (2% by weight) manufactured from a coal rock of the deposit “Saryadyr” “Corporation “ON-Olzha” LLP, Akmola region, Kazakhstan). The nanocarbon powder (150-200 nm) has been manufactured by three-stage size reduction of the coal rock: I – a mechanical dispergator (up to 2-3 mm), II – an aerodynamic mill (up to 20 mcm), III – a reactor with a rotating electromagnetic field. The neat bitumens of the grades BND 50/70, BND 70/100, BND 100/130 have been produced by the plants of Kazakhstan and Russia; they satisfy the requirements of the standard ST RK 1373-2013. The modified bitumens have been prepared in the laboratory of KazdorNII with the use of the neat bitumens, 7 types of the polymers, crumb rubber and polyphosphoric acid and they satisfy the requirements of the standard ST RK 2534-2014. It has been determined that the nanocarbon bitumen is one of the most resistant at the low temperatures: -24°С, -30°С and -36°С.

scholarly journals Nanostructured Bitumen with Nanocarbon

2019 ◽  
Vol 21 (4) ◽  
pp. 317 ◽  
Author(s):  
B.B. Teltayev ◽  
A.A. Kalybai ◽  
G.G. Izmailova ◽  
S.R. Rossi ◽  
E.D. Amirbayev ◽  
...  
Keyword(s):  
Low Temperature ◽  
Test Methods ◽  
Structure Variation ◽  
Temperature Resistance ◽  
Chemical Indicators ◽  
Excess Surface ◽  
The Cost ◽  
Physical And Chemical ◽  
Low Temperature Resistance

Physical and chemical indicators of bitumen quality of grade BND 70/100 with the added carbon nanopowder 2% by weight have been studied by laboratory test methods and analysis. High reaction ability of nanopowder particles and concentration of excess surface and internal energy in them have been determined, which provide the increase of low-temperature resistance, aggregate strength, and improvement of rheological properties of nanostructured bitumen. Essential structure variation has been proved: the increase of asphaltenes and oils content for 9% and 7.2% respectively due to the decrease of resins for 16.2% by weight. Methods have been discussed for preparing a liquid nanocarbon mix, adding of the mix into bitumen and homogenization of the bitumen. Some economic indicators have been represented which influence essentially the reduction for the cost value of the nanostructure bitumen.

Low-temperature resistance of higher plants is significantly enhanced by a nonspecific cyanobacterial desaturase

1996 ◽  
Vol 14 (8) ◽  
pp. 1003-1006 ◽  
Author(s):  
Osamu Ishizaki-Nishizawa ◽  
Toshio Fujii ◽  
Mizue Azuma ◽  
Keiko Sekiguchi ◽  
Norio Murata ◽  
...  
Keyword(s):  
Low Temperature ◽  
Higher Plants ◽  
Temperature Resistance ◽  
Low Temperature Resistance
Sign in / Sign up

Export Citation Format

Share Document