Properties graphene humid conditions

Properties of graphene change in humid conditions

Queen Mary, University of London

Properties graphene humid conditions
Credit: AlexanderAlUS/Wikipedia/CC BY-SA 3.0

Graphene exhibits very different properties in humid conditions, according to researchers from Queen Mary University of London. Properties graphene humid conditions

Graphene, which is made from carbon and was discovered in 2004, is hailed for many of its extraordinary characteristics including being stronger than steel, more conductive than copper, light, flexible and transparent. Properties graphene humid conditions

This study, published in the journal Physical Review B, shows that in bi- , which is two sheets of one atom thick carbon stacked together, water seeps between the layers in a humid environment.

The properties of graphene significantly depend on how these carbon layers interact with each other and when water enters in between it can modify the interaction.

The researchers found the water forms an atomically at 22 per cent and separates graphene layers at over 50 per cent relative .

This suggests that layered graphene could exhibit very different properties in a humid place such as Manchester, UK, where average relative humidity is over 80 per cent every month of the year, compared to a dry place such as Tucson, Arizona, where relative humidity is 13 per cent on afternoons in May but rises to 65 per cent on January mornings. So, in Tucson the properties will vary according to the time of the year.

Graphene, both layered and single layer, potentially has a huge number of uses but the results of this study could impact how the material can be used in real-life applications.

Lead author Dr. Yiwei Sun, from Queen Mary University of London, said: “The critical points, 22 per cent and 50 per cent relative humidity, are very common conditions in daily life and these points can be easily crossed. Hence, many of the extraordinary properties of graphene could be modified by water in between graphene layers.”

He added: “Some graphene-based devices may function to their full capability in dry places while others may do so in humid places. We suggest all experiments on 2-D materials should in future record the relative humidity.”Properties graphene humid conditions

The researchers suggest humidity is also likely to have an impact on other layered materials such as (sheets made of boron and nitrogen) and Molybdenum disulphide (sheets made of molybdenum and sulphur).

The study was carried out because it was known that graphite, a material also made from carbon, loses its excellent lubricating ability in low humidity conditions, such as aboard aeroplanes at high altitude, which was reported during the Second World War, or in outer space, as reported by NASA in the 1970s.

It was believed that the in between layers of graphite is crucial to its behaviour and now the same effect has been shown to affect layered graphene.

Explore further: Researchers have fabricated two types of trilayer graphene with different electrical properties

More information: A. Qadir et al. Effect of humidity on the interlayer interaction of bilayer graphene, Physical Review B (2019). DOI: 10.1103/PhysRevB.99.045402

Read more at: https://phys.org/news/2019-01-properties-graphene-humid-conditions.html#jCp

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Method precursors carbon fibers processing

A new method developed to produce precursors for high-strength carbon fibers processing

The results obtained by scientists at Lobachevsky University can be used to produce carbon fiber with new improved characteristics for use in Russia’s high-tech industries

LOBACHEVSKY UNIVERSITY

Carbon fiber is an important structural material of the 21st century. Due to its high strength, which is not inferior to metal alloys, in combination with low specific weight and high oxidative stability, it is an indispensable material for airspace and shipbuilding industry, construction, medicine, sports industry, and in other high-tech industry sectors.

The main method of carbon fiber production involves heat treatment of synthetic fibers obtained from polymers based on acrylonitrile.Method precursors carbon fibers processing

The quality of the finished carbon fiber and its strength characteristics largely depend on the composition and molecular weight characteristics of the polymer raw materials (precursors) from which the fiber is extruded.Method precursors carbon fibers processing

Therefore, the important tasks in the field of synthesis of precursors for carbon fibers are to search for new compositions for copolymerization, and to develop effective polymerization methods that enable the control of the molecular weight of the samples obtained. Method precursors carbon fibers processing

One of the latest achievements in modern synthetic chemistry of polymers is the development of methods for controlled radical polymerization (Reversible Deactivation Radical Polymerization.).

The advantages include the ability to control the molecular weight value of the polymers obtained by varying the ratio between the initiator and the monomer, as well as simultaneous fragment-by-fragment chain growth, which results in a narrow molecular weight distribution.

According to Ivan Grishin, head of the research laboratory for organic synthesis and radical processes at Lobachevsky University, UNN researchers’ work was aimed to develop a new method for producing acrylonitrile copolymer, which makes it possible to obtain a precursor for high-quality carbon fibers that feature high strength and elastic modulus.

To obtain these acrylonitrile copolymers, the method of controlled Atom Transfer Radical Polymerization (ATRP) was used for the first time, with copper bromide as a catalyst.

Due to the high initiation efficiency and the fragment-by-fragment chain growth, this method allows obtaining narrowly dispersed copolymers with specified molecular weights.

“As a result of our experiments, we obtained samples with molecular weights of more than 70 kDa and a narrow molecular weight distribution, which meets the requirements for copolymers to be processed into high-strength carbon fibers.

The important advantages of the proposed method are the use of very low concentrations of the catalyst (at the level of hundredths of a percent), as well as the high rate of the process, which is due to the use of glucose as an activator,” said Ivan Grishin.

In the course of the research, copolymers were obtained that feature a high degree of compositional homogeneity, as well as a predetermined molecular weight value and composition. The effect of comonomers on the behavior of samples in the process of their oxidative stabilization was investigated.

It is shown that by using the proposed composition based on three monomers (acrylonitrile, methyl acrylate and dimethyl itaconate) it is possible to achieve a significant reduction of the exothermic effect in the process of precursor oxidative stabilization, which has a favourable effect the mechanical properties of the resulting carbon fiber.

The composition and copolymerization method proposed by UNN scientists can be successfully used to produce acrylonitrile copolymers that can serve as precursors for high-strength carbon fibers.

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Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.

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Polymers Petrochemicals Recycling Textiles 23-01-2019

 

-China – Polyethylene Terephthalate

PET and its chain are assessed mixed.

PET Bottle grade export 1,050/1,085 $/ton – PET Bottle grade domestic market 8,300/8,400 yuan/ton – PET Filament grade SD domestic market 7,800/7,950 yuan/ton – PET Filament grade BR domestic market 7,800/7,900 yuan/ton

PTA Taiwan 825/835 $/ton – PTA domestic market 6,400/6,550 yuan/ton – MEG $ 615/630 $/ton – MEG domestic market 5,000/5,100 yuan/ton – PX Korea 1,060/1,075 $/ton

POY 150D/48F  domestic market 8,500/8,600  yuan/ton – DTY 150D/48F  domestic market 10,350/10,450  yuan/ton – PSF domestic market 8,900/9,000  yuan/ton

Polymers Petrochemicals Recycling Textiles

The Latest: Germany open to UK request for delay on Brexit

The Latest on Britain’s exit from the European Union :

Germany’s economy minister says a request from Britain’s government for an extension on the looming Brexit deadline would “certainly be considered seriously” — if a majority in Parliament seeks one.

Peter Altmaier says a no-deal or “hard” Brexit “must be avoided.” He called for patience as the British parliament considers a new plan by Prime Minister Theresa May’s government to make good on the verdict of the British people two years ago to leave the European Union.

Polymers Petrochemicals Recycling Textiles

Properties of graphene change in humid conditions

Graphene exhibits very different properties in humid conditions, according to researchers from Queen Mary University of London. Properties graphene humid conditions

Graphene, which is made from carbon and was discovered in 2004, is hailed for many of its extraordinary characteristics including being stronger than steel, more conductive than copper, light, flexible and transparent. Properties graphene humid conditions

This study, published in the journal Physical Review B, shows that in bi-layer graphene, which is two sheets of one atom thick carbon stacked together, water seeps between the layers in a humid environment.

Polymers Petrochemicals Recycling Textiles

Crude Oil Prices Trend

Polymers Petrochemicals Recycling Textiles

Teijin Frontier to display new fabrics at ORWM 201922

Teijin Frontier, the Teijin Group’s fibre and products converting company, has announced that the company is set to participate in the Outdoor Retailer Winter Market (ORWM) 2019, in stand #MR208. The world’s largest international sports and outdoor trade fair will be held at the Colorado Convention Centre in Denver, US, from January 30 to February 1, 2019.

The Teijin Frontier stand will exhibit Deltapeak and related hybrid materials that offer excellent combinations of performance, appearance, and texture for sportswear. The stand will also promote Teijin Frontier’s environmentally friendly solutions, including microplastics pollution prevention, reducing hazardous chemicals usage, fossil resource conservation, and CO2 emissions reduction, according to a press release by Teijin.

Polymers Petrochemicals Recycling Textiles

Faurecia to test-bed real-time emissions monitoring from a fleet of DHL commercial vehicles in Singapore

Faurecia has been awarded a two-year pilot project involving live tracking of emissions from a fleet of commercial vehicles

Following an innovation call from Singapore’s National Environment Agency (NEA) for demonstrations of real-time monitoring solutions for NOx and particulate matter emissions from diesel vehicles, Faurecia has been awarded a two-year pilot project involving live tracking of emissions from a fleet of commercial vehicles.

In partnership with DHL Express, the world’s leading international express services provider, Faurecia will equip a fleet of commercial vehicles with sensors to monitor NOx and fine particulates in real time using a unique sensing technology currently being developed by Faurecia.

Polymers Petrochemicals Recycling Textiles

China 2018 economic growth slows to 6.6%, a 28-year low

China’s economy registered a full-year 2018 growth of 6.6%, the lowest recorded in 28 years, official data showed on Monday.

In the fourth-quarter of last year, growth in the world’s second-biggest economy, weakened to 6.4%, the slowest pace of expansion since the first quarter of 2009, according to the National Bureau of Statistics (NBS).

The services sector posted a 7.6% growth in 2018, while industry and agriculture posted an expansion of 5.8% and 3.5%, respectively.

The NBS said that the economic figures in 2018 remained reasonable and largely met expectations. China had set a target full-year GDP growth of 6.5% GDP for 2018.

Amid the economic slowdown partly caused by the US-China trade war that began in July 2018, the Chinese government has introduced a series of stimulus measures during the year, including the easing on monetary policies, tax cuts and subsidies to companies that do not lay off employees.

Polymers Petrochemicals Recycling Textiles

Songwon and RPC bpi nordfolien partner to produce sustainable packaging containing 50 per cent recycled PE

Songwon has announced it is one of the first chemical companies in the world to package its products in 20kg PE bags made with 50 per cent recycled PE.

Songwon has collaborated with RPC bpi nordfolien to develop PE bags for packaging 20kg of product using recycled materials originating from different waste streams, including industrial printed bags that have already been used.

All of the solvents that are required for de-inking are also recycled continuously in a closed loop process.

Over the past twelve months, the recycled 20kg bags were successfully trialled on various customers to make sure that they met Songwon’s quality standards, as well as those of the customers.

Maurizio Butti, CEO at Songwon, said: “With RPC bpi nordfolien, we have found an innovative partner who can support us to live Songwon’s vision of ‘Sound and sustainable growth for all our stakeholders in harmony with the interests of our planet and its people’.”

Polymers Petrochemicals Recycling Textiles

A new method developed to produce precursors for high-strength carbon fibers processing

The results obtained by scientists at Lobachevsky University can be used to produce carbon fiber with new improved characteristics for use in Russia’s high-tech industries

Carbon fiber is an important structural material of the 21st century. Due to its high strength, which is not inferior to metal alloys, in combination with low specific weight and high oxidative stability, it is an indispensable material for airspace and shipbuilding industry, construction, medicine, sports industry, and in other high-tech industry sectors.

The main method of carbon fiber production involves heat treatment of synthetic fibers obtained from polymers based on acrylonitrile.

Polymers Petrochemicals Recycling Textiles

FCCI calls for abolishing duty on polyester, cotton yarn in mini budget

Faisalabad Chamber of Commerce and Industry (FCCI) President Syed Zia Alumdar Hussain Monday urged the government to abolish duties on polyester and cotton yarn in the financial bill, which was expected to be announced on January 23.

Addressing a press conference here at the FCCI Complex, he said the government had taken positive initiatives for revival of the export sector and now it should also end the levies on polyester and cotton yarn to decrease input cost in the domestic sector.

He said Federal Minister for Finance Asad Umar had assured the export traders on October 04 that their genuine problems would be resolved soon.

Polymers Petrochemicals Recycling Textiles

Green is the new black at future fabrics expo

‘That’s so last season’ is fast-becoming an antiquated expression as the fashion world embraces the real next big thing: the last big thing.

Fabrics and yarns crafted from waste — whether from post-consumer textile detritus or stalks, leaves and other food and wine product residues — are white hot. Plastic water bottles can also be recycled into yarn and cloth. And algae-derived materials are truly on the verge.

These are just some of the eco-friendly textile trends showcased at The Sustainable Angle’s Future Fabrics Expo, which takes place in London this January. Such materials and production methods — along with an event that brings together brands, designers, mills and suppliers, and the eco-curious — are not only in vogue, but also desperately needed.

Polymers Petrochemicals Recycling Textiles

Responding to the growing demand for plastic alternatives

The demand for bioplastics as an alternative to conventional oil-based plastics, is ever growing. Recent developments in European packaging and waste laws, boost that demand even more. But, it’s not just laws that force us to look for alternatives. Retailers, producers and consumers are becoming more and more aware of their carbon footprint and how important it is to become more sustainable. Less plastic means a better world for everyone.

Mediane may have found several possible answers for you on how to reduce your carbon and fossil footprint. They created the Greensleeve programme. Greensleeve packaging sleeves have been developed to achieve a more sustainable world.

Polymers Petrochemicals Recycling Textiles

Environment360 announces PET bottle recycling partnership with Qualiplast

Environment360, a non-governmental organisation (NGO) has announced a partnership with Qualiplast, one of the largest plastic producers in Ghana, to help support the collection of bottles made of polyethylene terephthalate (PET) by informal workers in Kumasi.

The partnership between the two parties is expected to leverage on Qualiplast’s transportation network to ensure that PET bottles collected in Kumasi are transported into Accra, Environment 360 announced in a statement.

“Plastic bottles, once in Accra, are further processed by Environment360 and then sold unto a third party that creates plastic straps for packaging,” the statement said.

Polymers Petrochemicals Recycling Textiles

How do investors view company moves on sustainability?

There are signs, Ben Cooper writes, that scepticism in the investment community about food companies’ moves on sustainability is starting to ease.

Now is perhaps a good moment to take stock of how investor attitudes to sustainability in the food sector have changed in recent years and may continue to do so.

Last month saw Paul Polman, sustainability standard-bearer-in-chief for the food industry and the wider corporate world, step down after ten years as chief executive of Unilever, a tenure defined by his groundbreaking and unrelenting focus on sustainability. Last week, the World Economic Forum (WEF) Global Risks Report 2019 confirmed climate-related issues, among the threats Polman sought to elevate in 2009, now dominate the long-term risk horizon.

Polymers Petrochemicals Recycling Textiles

Porcher Sport launches new avalanche airbag fabric22

Porcher Sport, the sports and leisure division of Porcher Industries, has launched the new ultra-lightweight avalanche airbag fabric for the safety of skiers and snow boarders. The company will unveil the revolutionary fabric plus other performance materials at their booth A4 407-4, at the ISPO 2019 trade show, to be held in Munich from February 3-6, 2019.

Considered the lightest fabric on the market with a super low weight of just 132g/square metres, Porcher Sport’s new performance fabric is proven to reduce the weight of avalanche bags by more than 12 per cent. Treated with an in-house formulated PU coating that is designed to resist the harshest of conditions, the material also boasts an extreme tear resistance, more than 50 per cent higher than other airbag fabrics. Easily repackable and compact, the fabric ensures the airbag can also be used for multiple deployments, according to Porcher.

Polymers Petrochemicals Recycling Textiles

IMF cuts 2019, 2020 oil price forecasts on global demand concerns

The International Monetary Fund Monday cut its forecast for average oil prices to just below $60/b in 2019 from close to $70/b in its last World Economic Outlook in October on concerns about global economic growth.

Further out, the IMF predicted oil prices would also average just below $60/b in 2020, down from $66/ b in its previous report.

It pointed to the increased volatility in oil prices since August due to the influences of US policy on Iranian oil exports and more recently fears of weakening global demand. Crude prices hit a peak of $86/b in October as some in the market talked of a return to $100/b oil before plunging to just below $50/b in late December.

Polymers Petrochemicals Recycling Textiles

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