2019 年 11 月 10～13 日にロンドンの王立化学協会の Burlington House で開催された Chemical Sciences and Society Summit（CS3 国際化学サミット）の白書を2020年6月3日00：01英国時間に公開される。CS3 は化学の領域で最先端の化学者が集まり，世界が直面する重要課題を取り上げて，少人数で解決に資する糸口を探り，その成果を広く公表することを目的とした会議体である。日本のほか，英国，ドイツ，中国，米国の主要化学会と各国のファンディングエージェンシーの全 10 機関で会議メンバーは構成されている。今回，諸事情により米国は不参加となったが，日英独中の 4 ヵ国が参加，主題として「Science to Enable Sustainable Plastics」を取り上げた。サブテーマとして「New plastics」「Recyclability of plastics」「Degradation of plastics」「Measuring the impact of plastics」の 4 つの分科会が開催され，分科会毎にキーノート（KN）とポジショントークが3～4件という構成で，総勢約35名で3日間にわたり議論をした。今回の議長はオックスフォード大学の C. Williams先生がつとめ，高原が今回日本のリーダーをつとめた。提言は https://www.rsc.org/new-perspectives/sustainability/progressive-plastics/ よりダウンロード可能である。
Plastic surgery: Chemistry experts unite to make plastics fit for the future
UNDER EMBARGO UNTIL 00:01 UTC WEDNESDAY 3 JUNE
Greener plastics are within our grasp – and they are essential for a sustainable future, says international group of researchers and funders.
New research is urgently needed to improve our understanding of plastics and their impacts, to secure a sustainable future for a material that fulfils vital roles in society – according to an international union of chemical societies and funding agencies.
Atsushi Takahara, Kyushu University joined learned societies and funders from China, Germany, Japan and the UK to develop a masterplan for creating a circular economy for plastics, by preserving the crucial function they serve in society while introducing much better recyclability and reusability into their design. The meeting was the latest edition of the Chemical Sciences and Society Summit (CS3), which takes place every two years.
Plastics’ worst environmental impacts are a common sight in the news or on social media, but they also play crucial roles in producing renewable energy and reducing the environmental impact of transport, as well as preserving fresh food and protecting it from contamination.
Plastics have also played a lifesaving role during the ongoing COVID-19 pandemic – as personal protective equipment such as masks, gowns and gloves all contain plastic.
A report on the findings, published today, says that with plastics likely to play a crucial role in healthcare and in low-carbon technologies in the future, it’s vital that new types of plastic are designed that can fulfil those roles without adverse impact on the environment. The report was published by the Chemical Society of Japan and JST partnership with an international group of learned societies and funding bodies.
Professor Charlotte Williams, Professor of Chemistry at the University of Oxford, who chaired the meeting, said:
“We use plastics because they can do things other materials cannot. We have an opportunity and an obligation to think about how we can re-design plastics to make them fully sustainable and fit for purpose, both for existing applications and for those we will need tomorrow. In the process, we must aim to reduce and even reverse some of the damage plastic pollution has already caused.
“The solution cannot be to ‘ban’ plastics or to replace them with alternative materials like paper, glass or metals. These alternatives also involve significant environmental impacts and in some cases are less sustainable than using plastics.
“Building a new future for plastics will require extensive collaboration across disciplines – including science, engineering, social sciences, policy, regulation and business.”
Future sustainable technologies may depend on plastics
Plastics are frequently demonized – often for the waste and pollution they cause – but they have benefits too.
In the future many technologies central to reducing our reliance on fossil fuels will depend on plastics. Wind turbine blades require plastic composites and adhesives, while batteries rely on plastics in their housing and may even apply them as electrolytes and other components. Plastics are also widely used in home insulation, reducing energy usage, and they play critical roles in the construction sector as pipes and conduits, cladding, seals, adhesives and gaskets.
Other future technologies such as robotics, drones, electronics, healthcare and diagnostics will also rely on the development of better plastic materials.
Plastic’s image problem exists in the production stage too, since most plastics are made from petrochemicals, the extraction of which causes pollution and the degradation of land. But in future they could be produced from more sustainable sources – such as from waste plastics or biologically sourced raw materials.
Chemistry has a central role to play
Technical solutions are urgently needed to ensure that in future plastics can retain their useful properties, whilst having a reduced environmental impact throughout their lifespan. Chemistry will play a central role in delivering these solutions.
Developments in chemistry will be key to understanding and mitigating the impact of plastics in the environment. Chemistry can help to develop efficient ways to recycle the plastics we use today and, in the longer-term, create replacements that are made from sustainable starting materials, are more amenable to recycling at end of life, and degrade more quickly to harmless by-products if they escape into the environment.
Four major research challenges
The new report – which is the output of a global summit held at the Royal Society of Chemistry in November 2019 – identifies four major research challenges. These four challenges are interlinked and are of equal importance.
• Understand the impacts of plastics throughout their life cycles. We need a suite of technologies and assessment tools to improve sustainability throughout plastics life cycles – from obtaining raw materials and manufacturing plastics, to better recycling and disposal options and fully understanding all the environmental impacts. Analytical methods and predictive models will be key to understanding the structure, properties and behaviour of micro and nanoplastics currently in the environment.
• Develop new sustainable plastics. New plastics must be designed with circular economy in mind from the design stage. This involves designing polymer structures with specific properties that allow plastics to be manufactured, processed and recycled with minimal negative environmental impacts.
• Closed loop plastics recycling. More efficient recycling processes are needed across the board – including in separating mixtures and composites into single pure polymers, and in enabling ‘chemical recycling’ – that is breaking polymers down into smaller molecules for future use.
• Understand and control plastic degradation. The indiscriminate disposal of plastics into the environment must be stopped. Some degradable plastics will be needed and the focus should be on developing products that are both recyclable and environmentally degradable so they can be degraded to non-toxic biochemicals after multiple reuse or recycles. It is also important that labelling standards are improved to ensure clarity and standardization of terms such as compostable, biodegradable and degradable polymers.
To read the report, visit https://www.rsc.org/new-perspectives/sustainability/progressive-plastics/