GBL-based electrolyte for Li-ion battery: thermal and electrochemical performance

betteries

Thermal stability, flammability, and electrochemical performances of the cyclic carbonate-based electrolytes [where γ-butyrolactone (GBL) is a main component (at least 50 vol.%) among of EC and PC with LiBF4] have been examined in comparison with contemporary (EC/EMC, 1:3 vol.%, 1 M LiPF6) electrolyte by DSC, accelerating rate calorimetry (ARC), AC impedance, and cyclic voltammetry (CV). This study shows that GBL-based electrolytes have perfect thermal stability and will improve Li-ion battery safety (including flammability) without performance trade-off with the accurate combination of active materials and separator. Several types of negative electrode materials (such as hard carbon, MCMB, and SWF) have been tested to evaluate GBL-based electrolyte influence on SEI formation and battery performance. Finally, GBL-based electrolytes show not only equal electrochemical performance in comparison to commonly used electrolytes (EC/EMC in this study) but it will notably improve battery safety.

https://link.springer.com/article/10.1007/s10008-011-1391-y

Gamma-Butyrolactone Regulatory System of Streptomyces chattanoogensis

antibiotics

ABSTRACT

Gamma-butyrolactones (GBLs) produced by several Streptomyces species have been shown to serve as quorum-sensing signaling molecules for activating antibiotic production. The GBL system of Streptomyces chattanoogensis L10, a producer of antifungal agent natamycin, consists of three genes: scgA, scgX, and scgR. Both scgA and scgX contribute to GBL production, while scgR encodes a GBL receptor. ΔscgA and ΔscgX mutants of S. chattanoogensis behaved identically: they had a growth defect in submerged cultures and delayed or abolished the morphological differentiation and secondary metabolites production on solid medium. ScgR could bind to the promoter region of scgA and repress its transcription. Moreover, scgA seems also to be controlled by a GBL-mediated negative-feedback system. Hence, it is apparent that GBL biosynthesis is tightly controlled to ensure the correct timing for metabolic switch. An additional direct ScgR-target gene gbdA was identified by genomic SELEX and transcriptional analysis. Comparative proteomic analysis between L10 and its ΔscgA mutant revealed that the GBL system affects the expression of more than 50 proteins, including enzymes involved in carbon uptake system, primary metabolism, and stress response, we thus conclude that scgR-scgA-scgX constitute a novel GBL regulatory system involved in nutrient utilization, triggering adaptive responses, and finally dictating the switch from primary to secondary metabolism.

https://aem.asm.org/content/77/23/8415.full

UN Commission Takes Appropriate Steps on BDO and GBL

united nations

Contact: Bryan Goodman, (202) 997-1606
Email: bryan_boodman@americanchemistry.com

WASHINGTON (March 13, 2015) – Today members of the UN Commission on Narcotic Drugs unanimously rejected the recommendation from the World Health Organization to list 1,4-butanediol (BDO) and gamma-butyrolactone (GBL) as Schedule I substances under the 1971 Convention on Psychotropic Substances. In response to these developments, the American Chemistry Council released the following statement.

“The UN Commission on Narcotic Drugs has unanimously rejected the recommendation from the WHO to list the industrial chemicals GBL and BDO‎ as Schedule I substances under the 1971 Convention on Psychotropic Substances. In fact, the 53 delegates unanimously agreed to not even bring the matter to a formal vote. As the delegates noted, such a classification would have severe economic consequences, disrupt many crucial industries, and affect country development agendas across the global economy.

“We support this decision in recognition of the strong product stewardship initiatives and controls that ACC member companies already have in place for these substances.”

https://www.americanchemistry.com/Media/PressReleasesTranscripts/ACC-news-releases/American-Chemistry-Council-UN-Commission-Takes-Appropriate-Steps-on-BDO-and-GBL.html

The Gamma Butyrolactone (GBL) and Butanediol (BDO) Panel

American-Chemistry-Council

The Gamma Butyrolactone (GBL) and Butanediol (BDO) Panel of the American Chemistry Council formed in 2000 to pursue initiatives related to advocacy, communications, education, testing and legitimate use of GBL (CAS # 96-48-0) and BDO (CAS # 110-63-4). The Panel‘s advocacy has focused on international, national, state and local initiatives through regulatory and legislative advocacy efforts. The Panel is composed of manufacturers and distributors of GBL and BDO.

Industrial and Commercial Uses

GBL and BDO have many industrial and commercial uses. One significant use of GBL is an intermediate in the manufacture of pyrrolidones, which are widely used industrial chemicals. A second significant use of GBL, because of its strong solvency properties, is in applications such as circuit board cleaning in electronics and high technology industries, and paint stripping. Other applications include the production of herbicides and as a processing aid in the production of pharmaceuticals. BDO is used as an intermediate in common industrial and commercial products such as polyether diols, urethane polymers and polyester polymers. Many of the polyester polymers are used as automotive components such as car bumpers. BDO is also used as a plasticizer, a carrier solvent in printing inks and a cleaning agent.

Commitment to Legitimate Use

The Panel is committed to the goal that GBL and BDO be used only for legitimate applications. Unfortunately, GBL and BDO can be converted into gamma hydroxybutyrate (GHB) and used for illegal purposes. To help prevent misuse, the producers of GBL and BDO formed the GBL/ BDO Panel of the American Chemistry Council.

The proliferation of illicit drugs in the United States is an issue of national importance. The Controlled Substances Act (CSA) provides the U.S. Drug Enforcement Administration (DEA) with tools to reduce illicit drug production by denying drug traffickers the chemicals they need to produce illicit drugs. GBL has been designated by the DEA as a List I chemical and is subject to the requirements of the CSA. Although BDO is not subject to Federal regulation, some states have designated it as a controlled substance. The majority of states are regulating GBL and BDO as controlled or listed substances.

Panel members diligently work with state regulators and enforcement agents including, the DEA and the U.S. Food and Drug Administration (FDA), to help investigate abuse of these chemicals. The Panel promotes the education of regulators and industrial users to prevent misuse of the chemical products. Companies have also individually instituted procedures to prevent diversions of these chemicals and encourage customers to do likewise.

As part of their continuing effort to help ensure their products are only used safely and properly, the Panel members support the following practices regarding sales and use of GBL and BDO. Specifically, Panel members:

  1. Promote awareness of applicable DEA and local requirements internally and to customers and distributors to assist in maintaining product security.
  2. Require written confirmation of intended use from customers to help ensure compliance with Federal, state and local requirements.
  3. Report suspicious, unusual product orders or sample requests to appropriate officials.
  4. Promote awareness of proper safety and handling procedures for GBL and BDO among distributors and customers.
  5. Assist regulators in drafting effective and workable regulations regarding the legitimate use of GBL and BDO.
  6. Monitor pending legislation to enable continued availability and responsible use of GBL and BDO for authorized applications.

For Further Information

The GBL/BDO Panel has created both a brochure and a “Question and Answer” to help inform persons who have questions about GBL and BDO.

https://www.americanchemistry.com/ProductsTechnology/GBLBDO/

Scientists Have Produced The World’s First 100% Recyclable Biopolymer

plastic-waste_1024

This plastic is 100 percent reusable and petroleum-free.

BEC CREW
11 DEC 2015

A type of plastic that can be reheated for an hour and converted back to its original molecular state has been developed by researchers in the US, and being completely recyclable and reusable, petroleum-free, and able to broken down by living organisms, it could change everything about how we consume and reuse plastic.

Researchers at Colorado State University developed the polymer using a monomer called Gamma-butyrolactone (GBL), which is found in superglue removers and cleaning solutions. While the scientific literature has insisted for years that its chemical structure was too stable to convert into a plastic, the team went ahead and tried it anyway.

“‘Don’t even bother with this monomer,'” Chen said, quoting the conventional wisdom. “‘You cannot make a polymer out of it because the measured reaction thermodynamics told you so.’ We suspected that some of the previous reports were probably incorrect.”

Right now, every single of one of us is consuming around 90 kilos (200 pounds) of synthetic polymers every year, most of which isn’t biodegradable or recyclable. More than 270 million tonnes of plastic is produced each year, and 18 million of that ends up in our oceans each year, adding to the 243,978 tonnes that have already accumulated.

While many of the plastic bottles and packages you use display a ‘recyclable’ symbol, they can only be reused to an extent. They can be processed and repurposed to give the plastic material a longer lifespan, but it’s not possible to convert them back to their base elements to start again.

The number of biodegradable plastics currently on the market come with the same limitations – only partially recyclable, and the process to extends their lifecycle results in unwanted byproducts. “The big drive now is to produce biorenewable and biodegradable polymers or plastics,” says Chen. “That is, however, only one part of the solution, as biodegradable polymers are not necessarily recyclable, in terms of feedstock recycling.”

That what’s so remarkable about this new type of bioplastic. Named poly(GBL), you just need heat it to between 220 and 300 degrees Celsius for an hour, and that’s all it takes to convert it back to GBL. Once back in GBL form, the polymerisation process can be begin again – under conditions of around -40 degrees Celsius, the monomer molecules react to form polymer chains or three-dimensional networks.

Chemist Eugene Chen and his team experimented with their new polymer, making different molecular shapes by changing up the catalysts – both metal-based and metal-free varieties – in the solution and elements of the production process. While scientists attempted the same thing 10 years ago, they couldn’t figure out how to convert the GBL into a polymer at anything other than crazy-high levels of pressure.

Chen and his colleagues determined that poly(GBL) is “chemically equivalent” to the commercially used biodegradable bioplastic, P4HB, but much cheaper and easier to produce because P4HB can only be derived from living bacteria. They hope poly(GBL) will end up replacing P4HB in the future, and maybe even other types of plastic, if they can figure out how to make production costs comparable.

The results have been published in Nature Chemistry, and Chen has also filed a patent for the discovery.

https://www.sciencealert.com/scientists-have-discovered-the-world-s-first-completely-biodegradable-biopolymer