Welcome to New ITS Members! Mirza Mahmood Ahktar, Lecturer, National Textile University, Faisalabad, Pakistan |
|
|
Sogol Asghari Product Development Specialist PRIMED Medical Products Edmonton, Canada |
|
|
Photo credit: Sogol Asghari |
|
|
As Product Development Specialist, I am involved in the design, development and innovation of medical supplies such as single-use surgical and procedural masks. My duties include, but are not limited to, product research, defining product specifications, technical reviews of products and projects, and ensuring the technical aspects of products are accurate. I earned a bachelor's degree in Textile Engineering from Amirkabir University of Technology in Iran and a Master of Science degree in Textile Sciences from the University of Manitoba (U of M). After graduating from U of M, I worked with the fabric/apparel design and sourcing team as a Product Manager at an apparel company in Winnipeg. I was thrilled to learn of the Product Development Specialist position at PRIMED because it matched perfectly with my previous training and education, especially with my Master's specialization/research. Everything I learned from my two degrees prepared me well for my current work at PRIMED; my knowledge and skills related to non-wovens, biocompatibility, and test methods are just a few examples of what I regularly apply to my job. How time flies - I have been part of PRIMED for well over 4 years now! Textiles is such a multi-disciplinary field. In addition to the specific areas of knowledge related to medical textiles, my interest in design and experiences gained in my brief employment sourcing fashion fabrics add to my ability to solve product development problems. Before moving to Edmonton, I had lived in other Canadian cities. No matter where I live or work, I allow myself to explore and view challenges as opportunities. In my leisure time, I love to take care of my plants, watch movies, and play the piano and setar. “Sometimes, the path you least expect will take you exactly where you want to be." |
|
|
Elena Kosareva is a Textile Science PhD candidate in the department of Human Ecology at the University of Alberta. Prior to traveling to Alberta, she received a Specialist Degree in Apparel Pattern-Making and a Master of Science in Engineering and Technology of Garments from the Saint Petersburg State University of Industrial Technologies and Design. (Photo credit: Elena Kosareva) |
|
|
Elena’s interest in textiles and garment construction started in primary school in a weekly sewing club. She was fascinated by the process of creating a 3-dimensional object from a 2-dimensional material and soon began creating her own sewing patterns. This interest led her to pursue a higher education in textile related fields. Her interest in textile science developed during her undergraduate education when working as a research assistant developing soil-repellent finishes for polyester and polyamide fabrics. Her pursuit of a PhD has allowed her to combine her industry knowledge and experience with a passion for learning more about textile science. Elena’s main area of interest is in protective clothing for hostile environmental conditions. Her PhD thesis examines protective clothing for wildland firefighters who face extreme conditions, including open flame, smoke, radiant heat, and physical fatigue due to working in dangerous conditions for long periods of time. The challenge of creating wearable textiles with an appropriate balance between providing comfort and protection inspired Elena to choose wildland protective clothing as her PhD research topic. She is currently researching how novel textile materials can provide improved heat and flame resistance while allowing ventilation to reduce physiological strain. Elena is motivated by the desire to help create improved protective clothing for those where risk their lives protecting our communities. Elena also has a great interest in protective clothing for space exploration, especially extravehicular activity (EVA) suits worn by astronauts. She finds the complexity of EVA suits and their role of mimicking Earth’s habitable conditions fascinating. Elena believes that textiles are important to human life as textiles can create microclimates of habitable conditions for humans to live and work in areas otherwise inhabitable. Textiles can provide excellent levels of protection from environmental extremes, while maintaining comfort for the wearer. |
|
|
Fibre Fineness Measurement Using Resonance Frequency |
|
|
Martin Forest, M.Env, Chemist (ITS member since 2018) Quality Assurance Manager, FilSpec Inc., Québec, Canada Our “The Lighter Side” segment of our March 2021 newsletter introduced a connection between guitar strings and ASTM fibre testing. As promised, detail about this relationship follows. What do textile fibres and guitar strings have in common? Apply a tension to them and they will vibrate to a certain resonance frequency. The lighter the string or fibre, the higher its frequency will be. Although it is used to make music with stringed instruments, this principle is also the basis of test method ASTM D1577, option C, for fibres in the textile world. Why use an indirect method? One of the main characteristic properties of a textile fibre is its linear density, also known as fineness. Linear density can be defined as mass per unit length. Standard units used to express linear density of spun yarn and filament yarn is the tex (grams per 1000 meters), while for individual fibres it is more common to use the decitex (grams per 10,000 meters) or the denier (grams per 9000 meters) (1). The linear density of spun yarn and filament yarn is readily measurable with a direct method: measuring the mass of a known length and calculating the mass per unit length (2, 3). One could argue that the same method can be applied to individual fibres. In practice, however, the weight of one fibre is too small for an accurate mass measurement. For instance, a typical staple fibre used for spun yarn manufacturing with a 50 millimeter length and a 2.0 decitex (1.8 denier) linear density has a mass of 0.01 milligram. This amount is too small to accurately weigh on an analytical balance and necessitates an indirect method that requires no weighing at all. How ASTM D1577 option C works? A textile laboratory instrument called the vibroscope plays “notes” to the fibre and determines which of those “notes” (frequencies) has induced the strongest fibre vibration. See further details in figure 1. To be fair, the vibroscope does not play discrete notes like Do, Ré, Mi, but a continuous spectrum of frequencies like a slide trombone would, but much higher in pitch. After the detection of the fibre’s peak resonance frequency, equation 1 below (5), which is derived from the physics laws of standing waves on a string (6), is used to calculate the linear density. |
|
|
Figure 1 - Adapted from (4) |
|
|
Schematic drawing of the vibroscope components (a) and vibroscope screen display (b). The vibrating length and pre-tensioning weight are fixed prior to the test. Then, acoustic transducers play a continuous range of sinusoidal sound wave frequencies, which cause the fiber to vibrate. The vibration amplitude is detected by the opto-electronic sensor, and graphically displayed on the screen. The vibroscope also performs the calculation per equation 1 and reports the linear density result in decitex units. |
|
|
Equation 1 - Adapted from (5) |
|
|
d = Linear density of the fiber (decitex) T = Pre-tensioning weight (centinewtons) f = Peak resonance frequency (Hertz) L = Vibrating length (millimeters) |
|
|
Conclusion Weighing single fibres is practically impossible to perform accurately since each fibre is so light, which is why the vibroscope method was developed, allowing measurement of a fibre’s linear density with a 1% error (5). Measuring the resonance frequency per ASTM D1577, option C (vibroscope) to determine fibre fineness is therefore a much more reliable method than one that would involve weighing the fibres. References (1) Anthony R. Bunsell, Sébastien Joannès, Alba Marcellan Testing and characterization of fibers, Editor(s): Anthony R. Bunsell, In The Textile Institute Book Series, Handbook of Properties of Textile and Technical Fibres (Second Edition), Woodhead Publishing, 2018, Pages 21-55, ISBN 9780081012727, https://doi.org/10.1016/B978-0-08-101272-7.00002-X. (2) ASTM D1907 / D1907M-12, Standard Test Method for Linear Density of Yarn (Yarn Number) by the Skein Method, ASTM International, West Conshohocken, PA, 2018, www.astm.org (3) ASTM D1059-17, Standard Test Method for Yarn Number Based on Short-Length Specimens, ASTM International, West Conshohocken, PA, 2017, www.astm.org (4) Herbert Stein. (Year unknown). Single Fiber Fineness Tester Vibromat ME (technical brochure). Textechno, Mönchengladbachm, Germany. (5) Author unknown. (Year unknown). Operation Instructions for the Vibromat ME Single Fiber Fineness Testing Instrument. Textechno, Mönchengladbachm, Germany. (6) Arthur H. Benade. (1990) Fundamentals of Musical Acoustics. Dover Publications. ISBN 048626484X, 9780486264844. 596 pages. |
|
|
The Lighter Side - Never Too Soon for Continuing Education |
|
|
Meet Camille and Évelyne, daughters of Martin Forest, our fearless newsletter committee chair. Camille is 5 years old and Évelyne is 10 months old. They look very serious about what they are doing. Merci, Martin, for sharing such a lovely photo with us. |
|
|
Photo credit: Martin Forest |
|
|
ITS Board of Directors 2021-2022 Officers President - Lena Horne (MB) Vice-President - Patricia Dolez (AB) Secretary - Vincent Deregnaucourt (QC) Treasurer - Sébastien Couture (QC) Directors Sogol Asghari (AB) Martin Forest (QC) Mazeyar Parvinzadeh Gashti (BC) Laura Munevar (AB) Forrest Sloan (Virginia, USA) Observers Joël Renaud (QC) Harishkumar Narayana (BC) |
|
|
|
|
