Apparatus and method for measuring the elasticity of microfibers at high throughput

Patent metadata

Field	Value
Publication number	US-12474245-B2
Application number	US-202318336266-A
Country	US
Kind code	B2
Filing date	Jun 16, 2023
Priority date	Jun 28, 2022
Publication date	Nov 18, 2025
Grant date	Nov 18, 2025

Abstract

The subject invention pertains to a new method for measuring the elastic properties of microfibers by rope-coiling. Rope-coiling refers to the buckling of a slender elastic fiber caused by axial compression. A continuous flow microfluidic method enables the high-throughput measurement of the elasticity of microfibers by rope-coiling, where sample loading and unloading are not needed between consecutive measurements. In certain embodiments the coiling radius can be directly proportional to the elastic modulus of the fiber, facilitating calibration to measure fiber elasticity for high-throughput applications. Throughput can be thousands of times higher than that of a tensile tester, making possible an in situ, on-line measurement in a microfluidic production line, which couples the making of microfibers and the measurement of elasticity on the same line. The new method can also measure certain fibers with local variations in elasticity.

First claim

We claim:

1 . A system useful for high throughput elasticity measurement of microfibers, the system comprising:
a coiling device configured and adapted for operable connection to a fiber making device; a coil measurement device configured and adapted to capture a coil radius (R coil ) measurement of a coil created by the coiling device; and a coil measurement calibration device configured and adapted to convert R coil to a fiber elasticity value (E).

2 . The system of claim 1 , wherein the coiling device is configured and adapted to receive a flow of a process fluid and a movement of a fiber from a connected fiber making device through an upstream portion to a downstream portion; the coiling device comprising a first capillary forming a small channel in the upstream portion and a second capillary forming a wide channel in the downstream portion.

3 . The system of claim 2 , wherein the second capillary is connected to and abruptly enlarged from the first capillary.

4 . The system of claim 3 , wherein the first capillary and the second capillary are each respectively configured and adapted such that together they create a condition of axial compression in the fiber sufficient to induce coiling under specified conditions and to form the fiber into a coiled fiber.

5 . The system of claim 1 , wherein the coil measurement device is a non-destructive measurement device.

6 . The system of claim 5 , wherein the coil measurement device is a non-contact measurement device.

7 . The system of claim 6 , wherein the coil measurement device is a microfluidics-based measurement device.

8 . The system of claim 5 , wherein the coil measurement device is a real time measurement device.

9 . The system of claim 1 , wherein the coil measurement calibration device is configured and adapted to convert R coil to E based on a linear relationship between R coil and E.

10 . The system of claim 9 , wherein the linear relationship comprises a slope determined according to R coil of the coiled fiber.

11 . A method useful for high throughput elasticity measurement of microfibers, the method comprising:
producing a microfiber having an elastic modulus (E) at a throughput greater than 1 mm per second; coiling the microfiber to create a coiled microfiber having a coil radius (R coil ); recording a measurement of R coil ; calculating E from R coil ; and uncoiling the coiled microfiber.

12 . The method of claim 11 , wherein the measurement is a non-destructive, non-contact, real-time measurement.

13 . The method of claim 12 , wherein the measurement is an optical measurement.

14 . The method of claim 13 , wherein the throughput is greater than 2 mm per second.

15 . The method of claim 14 , wherein the throughput is greater than 10 mm per second.

16 . The method of claim 12 , wherein the recording a measurement of R coil and calculating E from R coil are repeated at least once per minute.

17 . The method of claim 16 , wherein the recording a measurement of R coil and calculating E from R coil are repeated at least once per second.

18 . The method of claim 12 , wherein the calculating E from R coil comprises the application of a linear relationship between E and R coil .

19 . The method of claim 12 , comprising the uncoiling the fiber after recording the measurement to produce a fiber that is straight and without coils.

20 . A system useful for high throughput elasticity measurement of microfibers, the system comprising:
a coiling device configured and adapted for operable connection to a fiber making device; a coil measurement device configured and adapted to capture a coil radius (R coil ) measurement of a coil created by the coiling device; and a coil measurement calibration device configured and adapted to convert R coil to a fiber elasticity value (E); wherein the coiling device is configured and adapted to receive a flow of a process fluid and a movement of a fiber from a connected fiber making device through an upstream portion to a downstream portion, the coiling device comprising a first capillary forming a small channel in the upstream portion and a second capillary forming a wide channel in the downstream portion; wherein the second capillary is connected to and abruptly enlarged from the first capillary; wherein the first capillary is configured and adapted to approximate the flow of the process fluid and the movement of the fiber from the connected fiber making device, and the second capillary is configured and adapted to create a condition of axial compression in the fiber sufficient to induce coiling under specified conditions and to form the fiber into a coiled fiber; and wherein the coil measurement device is a non-destructive, non-contact, image based, real time measurement device; wherein the coil measurement calibration device is configured and adapted to convert R coil to E based on a linear relationship between R coil and E; and wherein the linear relationship comprises a slope determined according to R coil of the coiled fiber.

21 . A system useful for high throughput elasticity measurement of a target microfiber, the system comprising:
a rope-coiling device configured and adapted to induce rope-coiling in the target microfiber, thereby creating a coiled microfiber; a measurement device configured and adapted to measure one or more physical properties of the coiled microfiber within the rope-coiling device, thereby creating a coiled microfiber measurement; and a calibration device configured and adapted to convert the coiled microfiber measurement to a microfiber elasticity measurement.

22 . The system of claim 21 , wherein the measurement device is a microfluidic measurement device.

23 . The system of claim 22 , wherein the calibration device comprises a calibration curve, calibration formula, or calibration table.

24 . The system of claim 23 , wherein the rope-coiling device is a microfluidic device.

25 . The system of claim 24 , wherein the coiled microfiber measurement comprises a rope-coiling radius, diameter, or velocity and the calibration device comprises a linear relationship between the rope-coiling radius, diameter, or velocity and the microfiber elasticity measurement.

26 . A method useful for high throughput elasticity measurement of a target microfiber, the method comprising:
rope-coiling the target microfiber in a chamber, thereby creating a coiled microfiber; measuring one or more physical properties of the coiled microfiber within the chamber, thereby creating a coiled microfiber measurement; and converting the coiled microfiber measurement to a microfiber elasticity measurement.

27 . The method of claim 26 , wherein the measuring is done by a microfluidic measurement device.

28 . The method of claim 27 , wherein the converting is done by reference to a calibration curve, calibration formula, or calibration table.

29 . The method of claim 28 , wherein the chamber is a microfluidic device.

30 . The method of claim 29 , wherein the coiled microfiber measurement comprises a rope-coiling radius, diameter, or velocity and the reference to a calibration curve, calibration formula, or calibration table comprises a linear relationship between the rope-coiling radius, diameter, or velocity and the microfiber elasticity measurement

Assignees

• Versitech Ltd
• Univ Princeton

Inventors

• Liu Yuan
• Shum Anderson Ho Cheung
• Nunes Janine K
• Stone Howard A

Classifications

• G01N2203/0075

  Strain-stress relations or elastic constants · CPC title

• G01N3/08 Primary

  by applying steady tensile or compressive forces (G01N3/28 takes precedence) · CPC title

• G01N33/365

  Filiform textiles, e.g. yarns · CPC title

• G01N2203/0298

  Manufacturing or preparing specimens · CPC title

• G01N2203/028

  One dimensional, e.g. filaments, wires, ropes or cables · CPC title