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Interesting Polyurethane

Wearable sensors using PU - Developed in India

posted Aug 16, 2021, 4:28 AM by Rishi Madan

Dr Dipti Gupta from IIT Bombay has developed low-cost soft, flexible, and wearable sensors with potential applications in robotics, prosthetics, as well as minimally invasive surgery and identification of tumour/cancerous cells.


A very simple, low-cost approach was found for the fabrication of a pressure sensor based on polyurethane (PU) foam coated with the graphene-silver composite ink for highly conductive wearable electronics applications.

The technology which can be used to monitor the pulse waveform of a human radial artery in real-time is aligned with the 'Make in India' initiative, and Dr Gupta has applied for 3 national patents for these sensors.


Credit : https://www.devdiscourse.com/article/science-environment/1690379-tactile-sensorsdeveloped-using-low-cost-polyurethane-foam-and-nanomaterial-based-inks

Polyurethane eating mushroom !

posted Jul 12, 2021, 12:59 AM by Rishi Madan


Pestalotiopsis microspora, can grow on polyurethane and use it as its sole carbon source. This was discovered by Yale students on a class research trip in the Amazon rainforest in Ecuador back in 2011. The fungus,According to the Yale research team. The plain-looking light brown mushroom can live in environments with or without oxygen, breaking down and digesting polyurethane before turning it into organic matter. Another fungus, called Aspergillus tubingensis, could break down polyester polyurethane into smaller pieces after two months.

Research clearly shows that these types of mushrooms can break down plastics in weeks or months, potentially producing a protein
-rich food for animals, humans, or plants. With more research, mushrooms could help address our plastic pollution problems. We can envision at-home recycling kits and community recycling centers with fungi systems built in to utilize this process.

It turn out that some of these mushrooms are edible ! this could be the solution for not only eradicating plastics but also eradicating world hunger !

Source : 
https://www.treehugger.com/mushroom-that-eats-plastic-5121023
https://en.wikipedia.org/wiki/Pestalotiopsis_microspora
https://vimeo.com/113942952

Gold-finger !

posted Dec 1, 2020, 12:41 AM by Rishi Madan

Two fingers are holding a small piece of metall. One finger is equipped with the nanomesh sensor.

Scientists from the Technical University of Munich (TUM) and the University of Tokyo have developed an ultrathin pressure sensor that can be attached directly to the skin. It can measure how fingers interact with objects to produce valuable data for technological or medical applications. The sensor has an unnoticeable effect on the users’ sensitivity and ability to grip objects, and it is highly resistant to disruption from rubbing.

A layer of polyurethane nanofibers serves as a passivation and carrier layer, followed by an ultra-thin layer of gold mesh, an intermediate layer of parylene-coated polyurethane nanofibers and finally another layer of gold mesh. Make up the sensor thats applied to the finger tips.

The nanomesh, constructed from polyvinyl alcohol (PVA) nanofibers and a gold (Au) layer, adheres to the skin when sprayed with water, dissolving the PVA, as depicted in the enlarged diagrams at bottom


Source & more information : 
https://www.tum.de/nc/en/about-tum/news/press-releases/details/36332/
https://newatlas.com/electronic-nanomesh-skin-wearable-sensor/50540/

Polyurethane from Trees

posted Nov 1, 2020, 11:01 PM by Rishi Madan

""
                                   Made from oil extracted from bark and mixed with CO2, this cyclic carbonate is 
                                   a precursor for polyurethane, a common form of plastic with a wide range of 
                                   everyday uses

The University of Toronto’s Ning Yan and her team showed that tree bark can be used to create an isocyanate-free version of polyurethane. The bark is liquefied into an oil, which is then mixed with CO2 to create a product known as cyclic carbonate, a precursor for polyurethane. The cyclic carbonate product contains 15 per cent CO2 by weight, providing a new path to sequestering the greenhouse gas.

Yan is the director of the newly formed Low Carbon Renewable Materials Centre (LCRMC) at U of T Engineering, which is supported by the dean’s strategic fund. LCRMC researchers work closely with forestry companies and industry associations to transform forest biomass – including materials that today are discarded as waste – into commercially valuable products.

Sources :

https://indiaeducationdiary.in/using-tree-bark-u-of-t-researcher-develops-new-generation-of-sustainable-products/

Neem Oil + PU for seed bags

posted Oct 26, 2020, 4:29 AM by Rishi Madan   [ updated Nov 1, 2020, 10:51 PM ]


Green Neem Tree, For Plantation, Rs 80 /piece Leafy Labs Private Limited |  ID: 22139341712
Azadirachta indica, commonly known as neem or Indian lilac, is a tree in the mahogany family Meliaceae. It is native to the Indian subcontinent. Products made from neem trees have been used in the traditional medicine of India for centuries.

In a novel use of neem tree oil, researchers from the IIT-H have developed neem oil encapsulated electrospun polyurethane nanofibrous bags for seed storage. The real-time storage experiment carried out for 75 days showed that 90 per cent of the seeds stored in these bags were uninfected, while 70 per cent stored in commercial bags were found to be infected with storage fungi.

The research, led by Chandra Shekhar Sharma, Associate Professor in the Department of Chemical Engineering at IIT-H, demonstrates the suitability of neem oil bags as an ideal storage system. “Polyurethane is the most favoured versatile polymer, and polyurethane nanofibers are elastic, semipermeable, thermally-stable with excellent strength." 

Sources :

https://en.wikipedia.org/wiki/Azadirachta_indica
https://www.newindianexpress.com/states/telangana/2020/oct/24/iit-h-develops-neem-bags-to-store-seeds-2214455.html


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