(Press-News.org) Long-awaited advances in reducing the cost of certain catalysts — substances that kick-start chemical reactions — have quietly led to production of super-strong forms of the world's most widely used plastics, according to the cover story of the current issue of Chemical & Engineering News (C&EN), ACS' weekly newsmagazine. These upgraded forms of polyethylene have led to availability of stronger, more durable consumer products ranging from garbage bags to camping cookware.
C&EN Senior Editor Alexander Tullo notes that the catalysts, called "metallocenes," engendered excitement years ago because they allowed production of stronger forms of polyethylene plastics. The world's most widely used plastic, polyethylene is a mainstay in plastic shopping bags and other items. However, hopes that metallocene plastics would replace conventional polyethylene plastics faded because of the high costs of these catalysts.
The article describes a revival in the use of metallocenes and expanded marketing of super-strong polyethylene plastics. The reason: New technologies have cut the catalysts' cost and fostered production of millions of tons of the new plastics. They are found in products such as stronger garbage bags, improved packaging materials, more durable fuel tanks, and tougher artificial turf for football and soccer fields.
INFORMATION:
ARTICLE FOR IMMEDIATE RELEASE
"Metallocenes Rise Again"
This story is available at
http://pubs.acs.org/cen/coverstory/88/8842cover.html
Behind-the-scenes advances underpin new super-strong plastics
2010-10-21
ELSE PRESS RELEASES FROM THIS DATE:
'Reaper' protein strikes at mitochondria to kill cells
2010-10-21
Our cells live ever on the verge of suicide, requiring the close attention of a team of molecules to prevent the cells from pulling the trigger. This self-destructive tendency can be a very good thing, as when dangerous precancerous cells are permitted to kill themselves, but it can also go horribly wrong, destroying brain cells that store memories, for instance. Rockefeller University scientists are parsing this perilous arrangement in ever finer detail in hopes that understanding the basic mechanisms of programmed cell death, or apoptosis, will enable them eventually ...
Obsessing over strep throat in kids
2010-10-21
A common infection in children, strep throat can lead to problems with a child's heart, joints or brain if left untreated. And when the brain is involved, motor and mental functioning may be compromised, leading to syndromes such as attention deficit disorder and obsessive-compulsive disorder (OCD).
While scientists have speculated on a link between OCD and childhood infections like strep for more than two decades, Prof. Daphna Joel and her team of researchers at Tel Aviv University's Department of Psychology have now scientifically demonstrated that strep can lead to ...
Frontal lobe of the brain is key to automatic responses to various stimuli, say scientists
2010-10-21
(Santa Barbara, Calif.) –– Some people may excel at riding a bike, tying a tie, or playing the piano, but those same people may find it difficult to explain or teach those skills to someone else.
These motor skills are learned in one part of the brain, whereas classroom instruction and information read in a book are acquired in another area of the brain, explained F. Gregory Ashby, professor and chair of UC Santa Barbara's Department of Psychology. This second area of learning is the frontal cortex –– the area immediately behind the forehead –– where executive function ...
Harm reduction cigarettes can be more harmful than conventional brands, researchers report
2010-10-21
RIVERSIDE, Calif. – To reduce the toxicity of cigarette smoke, tobacco companies have introduced "harm reduction cigarettes," often marketed as safer than conventional brands.
But stem cell scientists at the University of California, Riverside have found that even sidestream smoke (which burns off the tip of a cigarette) from harm reduction cigarettes impairs growth of human embryonic stem cells more than sidestream smoke from a conventional brand.
"Harm reduction products are not necessarily safer than their conventional counterparts," said Prue Talbot, the director ...
A redeeming role for a common virus
2010-10-21
Washington, DC – A common virus that can cause coughing and mild diarrhea appears to have a major redemptive quality: the ability to kill cancer. Harnessing that power, researchers at Georgetown Lombardi Comprehensive Cancer Center, part of Georgetown University Medical Center, are conducting a clinical trial to see if the virus can target and kill certain tumor types.
By the age of five, most people have been exposed to the virus, called reovirus. For some, it can trigger brief episodes of coughing or diarrhea while many other don't develop any symptoms. The body ...
Estrogen replacement therapy speeds ovarian cancer growth, new study reports
2010-10-21
Aurora, Colo. (Oct. 19, 2010)— Estrogen therapy used by menopausal women causes a type of ovarian cancer to grow five times faster, according to a new study by researchers at the University of Colorado Cancer Center.
Menopausal estrogen replacement therapy (ERT) also significantly increases the likelihood of the cancer metastasizing to the lymph nodes, according to the study, which will be published in the Nov. 1 issue of Cancer Research. The study was released online Oct. 19, 2010. Cancer Research, published by the American Association for Cancer Research, is the world's ...
Climate change may create tipping points for populations, not just species
2010-10-21
As Earth's climate warms, species are expected to shift their geographical ranges away from the equator or to higher elevations.
While scientists have documented such shifts for many plants and animals, the ranges of others seem stable.
When species respond in different ways to the same amount of warming, it becomes more difficult for ecologists to predict future biological effects of climate change--and to plan for these effects.
In a study published this week in the journal Nature, University of Wyoming ecologist Daniel Doak and Duke University ecologist William ...
Discovery of a mechanism that controls the expression of a protein involved in numerous cancers
2010-10-21
Researchers at the Institute for Research in Immunology and Cancer (IRIC) of the Université de Montréal have identified a new mechanism controlling the transmission of an abnormal signal at the origin of several cancers. In an article published in the journal Cell, Marc Therrien's team explains the recent discovery of a protein complex that controls the RAS/MAPK signalling pathway, responsible for some of the deadliest cancers, including pancreatic, colon and lung cancers, and melanomas. This regulating mechanism could prove to be a promising therapeutic target for the ...
3 NASA satellites capture Typhoon Megi strengthening again
2010-10-21
Three NASA satellites are keeping tabs on Typhoon Megi and noticed that it was strengthening in the South China Sea today, but increasing wind shear may again weaken the system over the next couple of days.
NASA's TRMM, CloudSat and Aqua satellite captured images of Megi's clouds, rainfall and eye as they passed over the storm and saw clouds higher than 9 miles filled with ice, creating heavy rainfall.
The Tropical Rainfall Measuring Mission (TRMM) satellite passed over Typhoon Megi from its vantage point in space on October 18 at 2321 UTC (7:31 p.m. EDT) and saw that ...
GOES-13 sees system 99L organizing tropically
2010-10-21
The GOES-13 satellite keeps a continuous eye over the eastern U.S., the Caribbean Sea, Gulf of Mexico and Atlantic Ocean, and noticed that System 99L is much better organized today, October 20, hinting that it could become a tropical depression later today.
At 8 a.m. EDT on Wednesday, October 20, System 99L, a low pressure system about 150 miles southwest of Grand Cayman appears to be getting organized as it drifts eastward in the Caribbean Sea.
System 99L is showing more organization than it did yesterday, despite strong upper-level winds that are currently inhibiting ...