Dear @Aisha Tanvir, you could use this SOP http://electrospintech.com/SOP-ES2002.html#.XIe4hR4xUwA

Hopefully, it will be useful to you as it is useful to me.

Aisha, try electrospinning your fibres on a substrate that you could remove/dissolve. Wax could be an example but you need to make sure the adhesion to your fibre is minimal once you melt the substrate (providing mild heat is not an issue for your fibre). There are other options but wax coating on your counter electrode could be a quick start. As for snapping the sample at the point of contact with the test rig, this is not uncommon and why part of the ASTM is to use dogbone structure. If you could shape your electrospun mats to follow a dogbone shape the load on contacts will be distributed onto a larger area, so your effective test area will be the narrow part right in the middle. Am sure you can get more details on the dogbone standards of the web.

Dear

I didn’t find any Standard test method when I read publication many researchers applied their method. I can describe my own method.I cut nanofiber mats (50mmx10mm). Distance between the two clamp 25 mm. I applied 50 N load cell at a speed of 15 mm/min. As you said electrospun mats so fragile and thin. Test machine clamp create problem such a jaws break or slippage. I mounted samples with aluminium foil.

Dear Aisha Tanvir ,

According to ASTM E8/E8-15, these test methods cover the tesion testing of METALLIC MATERIALS at ROOM TEMPERATURE in any shape or developed products like alloys. Therefore, depend on your structure of your material, you must chose the proper standard guidance which i don't think ASTM standard series work here.

Best wishes,

Nemat.

Dear Aisha DIN50125 is a standard for tensile test

My dear,

Look ASTM D638 standard.

Hope this helps.

As you know these nanofiber are so weak, therefore when you try to determine its properties you fail due to the non uniformity. For this reason we have developed new techniques in our Research Lab.

1. You need to allign the nanofiber to make uniform structure.When you produce alligned nanofiber structure you can measure the properties.

2. If your structure is too weak for standart techniques , you may try special tensile stages for SEM. There are some special SEM specimen holders developed for these nanofiber applications.

Actually I also tried the ASTM 558 standard for my polymer flim. But I didn't get any appropriate line graph. It was irregular. So, I want to request you that if you find any suitable method or standard to measure the tensile strength for electrospun fiber please update...

See the paper: How Nanofibers Carry the Load: Toward a Universal and Reliable Approach for Tensile Testing of Polymeric Nanofibrous Membranes

Macromolecular Materials and Engineering, 2021, 2100183

https://doi.org/10.1002/mame.202100183

Currently, ASTM or ISO standards for tensile properties evaluation of electrospun nanofibers/nanofibrous mats are not available.

Most researchers recommend using a paper frame to fix the nanofibrous membrane for preventing nanofibers damage and better handling the specimen.

However, a more critical problem is the correct normalization of the force recorded by the load cell during the tensile test to obtain the stress-strain curve and, consequently, calculate elastic modulus (Young's modulus) and strength. Indeed, to calculate the stress, the membrane thickness measurement is necessary. However, the measured thickness is affected by the pressure applied to the porous mat during its measurement, so it is impossible to measure the "right" thickness and, as a consequence, the specimen section.

To bypass this problem, a load normalization based on sample mass instead of its cross-section area is helpful. Since the mass measurement is reliable, the calculated stress, elastic modulus, and strength are, in turn, reliable. Furthermore, this method reduces errors in load normalization owing to any thickness variation in the specimen, and the contribution of the mat porosity is discarded. Moreover, it is very powerful when dealing with membranes with a very low thickness, being in such cases the thickness measurement very tricky and completely not reliable.

More information about the tensile test data normalization based on specimen mass (and other very easy-to-measure quantities) can be found on the research article:

---> How Nanofibers Carry the Load: Toward a Universal and Reliable Approach for Tensile Testing of Polymeric Nanofibrous Membranes

Macromolecular Materials and Engineering, 2021, 2100183

https://doi.org/10.1002/mame.202100183

This paper also presents a data fitting model applicable to tensile test data of nanofibrous mats, as well as the effect of nanofiber diameter and nanofibers crossings on the tensile behaviour of membranes made of nanofibers.

See also the following videos:

---> How to correctly prepare nanofibrous mat specimens for tensile testing

https://www.youtube.com/watch?v=tVnjZ3O_Pjo

---> Reliable tensile testing of nanofibrous mats

https://www.youtube.com/watch?v=V8VTt5y8xCI

In the following papers, the proposed mass-based normalization method was positively applied to different nanofibrous mats, even rubber (elastomeric) nanofibers:

---> Rubbery nanofibers by co-electrospinning of almost immiscible NBR and PCL blends

https://doi.org/10.1016/j.matdes.2019.108210

---> Morphology, thermal, mechanical properties and ageing of nylon 6,6/graphene nanofibers as Nano2 materials

https://doi.org/10.1016/j.compositesb.2018.11.096

---> Rubbery-Modified CFRPs with Improved Mode I Fracture Toughness: Effect of Nanofibrous Mat Grammage and Positioning on Tanδ Behaviour

https://doi.org/10.3390/polym13121918