Generation Of Elastomers Research Articles

Healable, Recyclable, and Mechanically Tough Polyurethane Elastomers with Exceptional Damage Tolerance.

There is a huge requirement of elastomers for use in tires, seals, and shock absorbers every year worldwide. In view of a sustainable society, the next generation of elastomers is expected to combine outstanding healing, recycling, and damage-tolerant capacities with high strength, elasticity, and toughness. However, it remains challenging to fabricate such elastomers because the mechanisms for the properties mentioned above are mutually exclusive. Herein, the fabrication of healable, recyclable, and mechanically tough polyurethane (PU) elastomers with outstanding damage tolerance by coordination of multiblock polymers of poly(dimethylsiloxane) (PDMS)/polycaprolactone (PCL) containing hydrogen and coordination bonding motifs with Zn2+ ions is reported. The organization of bipyridine groups coordinated with Zn2+ ions, carbamate groups cross-linked with hydrogen bonds, and crystallized PCL segments generates phase-separated dynamic hierarchical domains. Serving as rigid nanofillers capable of deformation and disintegration under an external force, the dynamic hierarchical domains can strengthen the elastomers and significantly enhance their toughness and fracture energy. As a result, the elastomers exhibit a tensile strength of ≈52.4MPa, a toughness of ≈363.8MJm-3 , and an exceptional fracture energy of ≈192.9kJm-2 . Furthermore, the elastomers can be conveniently healed and recycled to regain their original mechanical properties and integrity under heating.

New Uses Keep Emerging for a Deceptively Simple Pump

Progressing Cavity Pumps Progressing cavity (PC) pumps have been around too long to be a young technology, but it is still an emerging one. The history of this rapidly growing form of artificial lift is a study in how a community of users can continue to find ways to adapt a seemingly simple machine that can have a complicated relationship with a reservoir. What started as a better option for pumping cold, heavy, sandy crude in Canada has been adapted for high-volume production of heavy crude in Venezuela, for lifting medium-weight oil mixed with things that other pumps cannot handle well, and pumping water out of Australian coal seams to initiate natural gas production from the thousands of wells in the huge deposits. All-metal versions are beginning to appear in heavy oil fields, after a decade of development and testing to prove they could work at temperatures far beyond what standard PC pumps could handle. Pushing the capabilities of these pumps, which cannot reliably handle light oil, will require a new generation of elastomers. This will likely require oil and gas industry users to push chemical makers to develop elastomers with capabilities that go beyond the needs of their biggest customers, auto parts makers who use them for tires and other car components. Several companies recently have begun trying to persuade users to turn to PC pumps powered by permanent magnetic motors downhole rather than relying on rotating rods powered by sur-face units. The advocates of downhole power, which has been a small part of the business, say it can allow more effective PC pump use and reduce tubing damage caused by long rod strings, which can also come apart. Innovative new pumps are appearing, with some using the usual materials in surprising ways. “The manufacturing of PC pumps is growing and I think everybody is trying to push the envelope a lot now,” said Shane Latoski, product manager of Oil Lift Technology, which is part of Dover Corporations’ Norris Production Solutions operation. “There are some interesting things coming through.” The company is in the middle of a rapidly growing business—PC pump makers are also benefiting from the strong sales of mud motors, which are the different use of the original design. The growth of the PC pump business is an example of the value of adaptive reuse. While emerging technologies are associated with scientific breakthroughs, mature businesses can find and profit from emerging opportunities that grow out of their normal business, said Pradeep Anand, president of Seeta Resources, a business consultant who has advised companies seeking such opportunities.