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Material engineers at Aalto University are claiming to have made a breakthrough in designing surfaces that can repel oil when wet, and yet can also repel moisture when oily. Whilst full verification of the results has yet to be carried out, the discovery may be the first in a new wave of materials that could revolutionise both the surfactant and coatings industries.

The new surface materials are able to function in this way because  they don’t need isolating air to stay trapped between the droplet and rough surface to prevent wetting. As a result, these ‘novel dual superlyophobic surfaces’ are able to repel oil when submerged or covered in water, as well as repel water when covered in oil. Something that the researchers believe has, “So far, been regarded as contradictory to each other and not expected to be present on the same surface.”

The online scientific journal ScienceDaily, describes how, “[The] Researchers propose two design criteria for new surfaces: the liquid filling criterion and the steady composite interface criterion. The design criteria lead to steady trapping of airless oil and water films within surface texture. Such liquid films enable both underoil superhydrophobicity, repelling water under oil, and underwater superoleophobicity, repelling oil under water.

Surfaces are prepared by the combination of re-entrant topography and delicately matched surface chemistry.”

The researchers have published their results in the journal Advanced Materials, where they describe the breakthrough in more detail as follows: “We consider the surfaces need to meet two design criteria i) the microstructures must be readily filled by water and oil without trapped air layer when submerged in one of the two liquids; ii) the submerged microstructures can support steady oil–water interfaces when the second liquid is introduced, or in other words, the second liquid can be suspended by the texture rather than that it intrudes into the texture.

The first criterion would create a water or oil film trapped within the texture and the second one guarantees the trapped liquid film not to be displaced by the other suspended liquid. Under the above two criteria, Cassie-type composite interfaces can be obtained in both water-in-oil and oil-in-water situations, and moreover large apparent CAs are able to be induced, both of which are important for liquid repellency — repelling of the second liquid by the first liquid in oil–water systems.”

This image was taken from the researchers’ publication, and shows how the dual superlyophobic surface keeps the oil droplet separate in water when it is against the surface.

As co-author in the study, Assistant Professor Robin Ras, explains, “Such surfaces can be regarded as an environment-responsive material which means its surface wettability changes with the environmental liquid it contacts. Unlike other responsive surfaces, the new surface does not rely on reconfigurable organic molecular modification, and thus offers a new strategy to make smart materials. When processed in the form of porous materials, it may be used for separation of both water-in-oil and oil-in-water emulsions, whereas common oil/water separation materials work for one type of emulsion only.”

If the discovery holds true, then it may allow for major design alternatives for many chemical manufacturers. For example, marine industries often rely on chemical products that give underwater protection from organic fouling or oil contamination. By repelling oils, these materials may provide alternatives to surfactant products.

Similarly, new coatings designed to repel water in order to inhibit corrosion may be developed based on the discovery.

Xuelin Tian, who was a postdoctoral researcher in Aalto University before recently becoming a professor at Sun Yat-sen University, China, can also foresee many practical applications for the new materials. Explaining how, “The competitive interaction with surfaces between oil and water plays an essential role in various technological applications. Our new design strategy of surfaces can be used in many ways from self-cleaning to dirt-repellency.”

Like many ground breaking technologies the full impact of these ‘novel dual superlyophobic surfaces’ is not yet known, but it is certain to attract the interest of coating manufacturers, surfactant producers and chemical feedstock traders in numerous industries. Whilst only time will show the full scope of applications, we can ask ourselves, ‘What is the best use of a material that repels oil when wet, and wetness when oily?’

Photo credit: Xuelin Tian, Robin Ras

Main photo credit: www.amouraimee.com

When it comes to sourcing environmentally friendly chemical feedstock how certain can an industrial chemical trader or manufacturer be that raw materials are truly green? ‘Not very,’ is the answer according to a recent study, as researchers are now questioning if many chemical products thought of as eco-friendly alternatives may in fact do more damage than the products they are replacing.

The discovery came to light during a study of piezoelectric materials by researchers from the Engineering and Physical Sciences Research Council (ESPRC). By performing a full life cycle analysis they found that the replacement product, recommended by numerous global authorities and environmentalists, is actually more dangerous to the environment than the original.

The ESPRC is an institution that describes itself as, “the main UK government agency for funding research and training in engineering and the physical sciences, with investment of more than £800 million a year”.

The case revolves around finding an alternative to lead zirconate titanate (PZT), a ceramic perovskite material that is widely used in numerous electrical products, from sensors, such as ultrasound tranducers, to military hardware, such as RPG launchers, to high value ceramic capacitors used in electric circuitry.

Up until now, the go-to replacement has been potassium sodium niobate (KNN), which is used as a lead-free alternative. However, the true environmental impact of mining KNN was never fully included in previous comparisons, so lawmakers and manufacturers were recommending the product as a ‘greener’ substitute without knowing the full affect of its use.

The researchers have published their findings in the journal Energy and Environmental Science, which makes clear the dangerous use of the terms ‘green’ and ‘environmentally friendly’ until a full life cycle analysis has been conducted. The study states the analysis that was undertaken as follows; “A methodologically robust life cycle supply chain assessment based on integrated hybrid life cycle framework was undertaken within the context of the two piezoelectric materials. Results show that the presence of niobium in KNN constitutes far greater impact across all the 16 categories considered in comparison with PZT. The increased environmental impact of KNN occurs in the early stages of the LCA due to raw material extraction and processing. As a result, the environmental damage has already occurred before its use in piezoelectric applications during which it doesn’t constitute any threat. As such, the use of the term ‘environmentally friendly’ for the description of KNN should be avoided. Cost-benefit analysis of substituting PZT with KNN also indicates that the initial cost of conversion to KNN is greater, especially for energy usage during production.”

Professor Lenny Koh, co-investigator on the research, said: “Our findings demonstrate the pivotal role of life cycle analysis in determining the environmental sustainability of substitutions of materials. Materials scientists, engineers and industry must consider the life cycle impact of materials in design and manufacture before deciding on the preferred substituted choice. Legislative bodies play a leading role in enforcing such responsibility in order to protect the scarcity and criticality of materials resources and prevent unsustainable practices.”

Dr Taofeeq Ibn-Mohammed, lead author on the paper and ESPRC research associate, said of the study, “Overall, the research demonstrates that application of life cycle analysis and supply chain management to a strategic engineering question allows industries and policy makers to make informed decisions regarding the environmental consequences of substitute materials, designs, fabrication processes and usage.”

Meanwhile, Professor Reaney, principal investigator on the project, concluded that, “The research has strong implications for future legislation concerning piezoelectrics within the European Union and worldwide.”

The fact that chemical products once labelled as ‘eco-friendly’ and ‘green’ are now found to have a worse impact on the environment will have ramifications for chemical traders, manufacturers and suppliers alike. As the online scientific journal Phys.org reports, “These findings will have a significant impact on global policy and the manufacturing sector.”

How eager producers of ‘eco-friendly’ chemical producers will be to have the full life cycle analysis of their products carried out, remains to be seen.

Photo credit: Allboutfuels.com

With many parts of the world experiencing new legislation on chemicals, there is growing concern among chemical industry leaders over the challenges that the new bureaucracy is causing, with many beginning to count the cost of delays in bringing new chemical products to market. This has recently lead to Socma (the Society of Chemical Manufacturers and Affiliates) voicing its fears over the updated procedure for reviewing new chemical products, and to speak out over the way the red tape is impacting chemical producers’ ability to make products available to customers.

Commenting on the implementation of the Lautenberg Chemical Safety Act, which passed into American law in June 2016, Kelly Franklin, North American Editor at the industry journal Chemical Watch notes that, “Under the new law, the EPA (US Environmental Protection Agency) must now make an ‘affirmative finding’ of safety before a new substance is allowed on the market. If the agency decides a substance poses an unreasonable risk, it must issue an order to prohibit or restrict it.”

The number of new chemical products requiring EPA review is estimated to be around 1,000 per year, and these reviews are not necessarily small. This is because, to make an ‘affirmative finding’ means calculating the effects of all ‘reasonable foreseen’ uses. This in turn, may require the EPA to order a ‘section 5(e)’.

This part of the law requires that chemical producers provide sufficient information of the new product, so that it may assess the chemical product on the following criteria:

• Testing for toxicity or environmental fate once a certain production volume or time period is reached
• Use of worker personal protective equipment
• New Chemical Exposure Limits (NCELs) for worker protection
• Hazard communication language
• Distribution and use restrictions
• Restrictions on releases to water, air and/or land, and
• Recordkeeping.

All of which takes time. As Chemical Watch noted when it reported of one example where a chemical manufacturer, “… has a pending case that is in a mixture, and one of the major components of this is already on the TSCA inventory and is what contributes to the hazards.”

Under the new law, despite the fact that the chemical has previously been passed by the EPA, its use in a new product requires a full review, adding to the delay, and creating a backlog of chemicals needing to go market but awaiting permission to do so. The significance of which was outlined by Dan Newton, Senior Manager of Government Relations at Socma, when he explained how, “Timely access to market is very important, especially for batch manufacturers who make chemicals on demand.”

Furthermore, whilst this backlog for new products impacts businesses, calls are being made to implement the wholesale review of all chemicals listed on the US market. As Richard Denison, of the EDF (Environmental Defence Fund) writes on the non-profit organisation’s website, “A key reform under the Lautenberg Act is the requirement that the EPA generate an accurate, up-to-date list of all chemicals in active commerce.  This is to be accomplished by enforcing a rule to do a full ‘reset’ of the TSCA Inventory [some 85,000 chemical products] that distinguishes between active and inactive chemicals.”

The total cost of implementing the newly enacted Lautenberg Chemical Safety Act has been estimated at $100 million. Some of this will be paid by the chemical industry, and as such may have a negative impact on innovation, especially for smaller chemical companies.

As Newton explains, “As EPA continues to implement the new TSCA, much of how its success or failure will depend on resources and how they are allocated. Some of the resources will come from industry.  Twenty-five percent, or $25 million of program costs, whichever is the lower, will come from industry.

This creates somewhat of a dilemma. If EPA puts too much focus on section 5 new chemicals and attempts to get smaller businesses to foot more of the bill, innovation could be negatively impacted. We could see a significant decline in the number of new chemicals introduced, particularly by smaller companies.”

As the current trend of tightening industrial chemical regulations reaches its climax, with the EU’s REACH laws, the Korean Act on the Registration and Evaluation of Chemicals (K-REACH), China’s Existing Chemical Inventory (IECSC) and the US’s TSCA, all now passed into law (with more countries following suit), it will take time for chemical companies and the industry as a whole to measure the economic impact of the extra red tape.

But with economic stagnation a reality in Europe and Japan, and a threat in North America and even Asia, governments are becoming increasingly aware of the importance of the chemical industry to the global economy. As such, how long will it take before a review of the legislation and its impact will take place?

Every time a new law is introduced, there is a risk that part of it will not be effective or helpful. What sounds good in a government committee room or looks good in a white paper, does not always implement well in the real world.

So, when all the dust settles from the recent tsunami of law changes, and when all the analysis of the impact of chemical products is over, will anyone from government be free to test the impact of the law on the health of the chemical industry?

Photo credit: www.msdsonline.com