[Dedicated to passionate scientist Dr Mashiur Rahman]
Microwave Irradiation Technique to Enhance Protein Fiber Properties, M Tsukada, S Islam, T Arai, A. Boschi, G Freddi, Autex Research Journal 5(1), 40-48, 2005
Courtesy of Autex Research Journal, Vol. 5, No. 1, March 2005
Added from Canada ~*~ 2010 November 13.
ইমেইল: firstname.lastname@example.org :: ওয়েবঃ textek.weebly.com :: Canada :: www.linkedin.com/in/shafiul2009
“Tensile properties were measured with an automatic tensile testing machine (Tensilon UTM-II, Toyo
Baldwin Co, Ltd.) under standard testing conditions. Each value is the average of 20 measurements.
The constant drawing rate of the sample is 10 min/min, the load at full scale is 500g, the sample
length is 10cm, the chart speed is 200 mm/min and the strain rate is 40 mm/min”
May I know the name of your standard?
Kafi, Thank you for your interest and question. Please google for the name of the standard. More specifically you may find this inforamtion on ASTM’s website. If you fail to find the information, I will dig deeper…. I have all ASTM standards on my old computer. That computer is in the box right now. Let me know if I can be of further assistance to you.
Thanks Shafiul. I already got standard test method for tensile properties of yarns by single strand method, which is ASTM D2256/D2256M-10, however, I need to find a standard for multifilament tow having 1-1.3 denier/filament, any idea?
Hi Kafi, Great! Please search ASTM site. You can reach them by email too. What is the tow size? For high performance fiber you may need special grip to avoid any slippage during tensile testing. Further, do you know the theoretical break strength? This should be the basis of selecting the right load cell and grip.
We have been trying to get some from a Turkish based company which should between 6K-24K, don’t know the breaking strength util I get the specification in details.still waiting..
Hi Shafiul, I hv been currently thinking to make a set up to heat treat the acrylic fibres under tension. It should be lab scale which is able to simulate actual process of fibre manufacturing. My idea is to use simply the batch process, however, it is better if I could find anyone selling the lab scale furnace allowing continuous process, alternatively we are interested to attach tensioner to our tube furnace and other end of the fibre with the instron load cell…not sure how it will be simple!! hope you could help!!
Kafi, Excellent. For the twist-less tow, you may have to apply a little twist to get a clean break. This will be reflected in the stress-strain curve. ASTM also offers a guideline on the amount of twist to be applied based on the dtex/denier of the tow.
Kafi, Thanks. During the spider silk innovation, we steam annealed and heat-set our spider silk fiber under the predetermined load, steam, temperature and time in the autoclave to produce super-fine fiber. You may find more information in our patent posted in the textile section. Hope you will find this idea helpful.
Methods and apparatus for spinning spider silk protein, S Islam et al., USP 7,057,023 Jun 6—is it the right one?
Kafi, Yes…. Thanks.
Hi Shafiul, I went through USP 7,057,023 and found only the followings as closer to my interest:
“In still yet other embodiments, the bath is at a temperature of 50C. to 100° C. In preferred embodiments, the filament is drawn through steam. Other plasticizers include isethionic acid, pyrrolidone, piperidine, morpholine, and glycerol, another preferred plasticizer. Alternatively, small batches of biofilaments may be drawn by hand or annealed in an oven under a tension weight”
How can I know more details about your equipment settings, i.e. annealing (steam) and heat setting (under tension?
Hello again Dr. Kafi, Thank you for your continual interest in my work. In the patent, we revealed a broader range and scope to cover a wide range of processing spectrum. Specific settings and process parameters are often considered proprietary information or trade secret. I recall our autoclave had the progressive time-dependent temperature and steam control options.
Each fiber has a unique physical properties. Your baseline guideline should be thermal and tensile data of the fiber, knowing your baseline and improving your baseline gradually. Apply load as a percentage of breaking force of the fiber and optimize all settings and processing parameters through the experimental work. Hoping these hints are helpful.
Thanks Shafiul for your valuable feedback. Now I have the following questions in my mind:
1. “Apply load as a percentage of breaking force of the fiber”–what percent?
2. how to maintain constant load while heat treating fibre? Please note my fibre face continuous shrinkage or elongation during the heat treatment.
3. How to treat fibres under constant length?
4. What set up did you use to treat fibre under both constant force and length?
5. Would you please provide 1/2 relevant papers/technical notes for 2/3/4?
Kafi, Thanks for your Qs. Here are prospective As to your Qs:
1: Trial and error! Keep the end result in mind. Applied load should reflect the anticipated outcome. An example: if you choose the 10% of the breaking strength and not getting the result U want, U have a choice. Either increase or decrease the load to optimize your critical structure-property-performance interrelationships.
2. Modern tensile testers offer all choices including environmental chamber to choose your most experimental options. Usual choices: a)constant rate of elongation (CRE) and b)constant rate of load (CRL). Further, you can stop the tensile tester at a predetermined length or load.
3. Keep your length fixed.
4&5. Please consult articles and patents. It should be a fiber specific custom solution.
Hoping you would find these hints/tips helpful. Good luck!
Referring to your answer 3 again—-
It was difficult to maintain a constant length during heat treatment as the fibre always shrink. I didn’t try it yet using our tensile tester, however, change in fibre length was obvious while experiment was conducted at fixed length simply using the tube furnace. Not sure tensile machine could solve this problem.
Referring to your answer 4&5—-
I did some search and havn’t got the right patent/article yet I exactly want. May I know what do you mean by “fiber specific custom solution”?
Thanks for your coopeartion.
1. Holding force should be considerably greater than the breaking force. Use effective grip, avoid slippage resist shrinkage or allow controlled shrinkage during heat-setting.
2. Each fiber has a unique visco-elastic property. Your load level should reflect the stress-strain curve. Do you need to select the load level beyond the initial modulus? Unlikely.