System and method for electrospun fiber straining and collecting
The invention provides a system and process for manufacturing nanofibers that integrate a post-drawing process in a continuous electro spinning manufacturing process. In certain embodiments, the system and process are capable of post-drawing multiple individual electrospun nanofibers simultaneously. In certain embodiments, the system can be configured and controlled to accommodate various materials that can be electrospun.
1. A system for forming an electrospun nanofiber array, comprising:
a first conductive collection surface further comprising a first proximate end and a first distal end;
a second conductive collection surface positioned facing the first conductive collection surface, further comprising a second proximate end and a second distal end, wherein:
the first proximate end and the second proximate end define a proximate gap between the first proximate end and the second proximate end;
the first distal end and the second distal end define a distal gap between the first distal end and the second distal end;
the first proximate end and the second proximate end further define a deposition area positioned within the proximate gap;
a first portion of the first conductive collection surface and a first portion of the second conductive collection surface are further positioned to define a track angle θ, wherein the length of the distal gap is different than the length of the proximate gap.
2. The system according to claim 1 , wherein at least one applies:
(a) the first portion of the first conductive collection surface and the first portion of the second conductive collection surface are aligned to each other and form two opposing sides of an isosceles trapezoid;
(b) a second portion of the first conductive collection surface and a second portion of the second conductive collection surface are parallel to each other.
3. The system according to claim 1 , wherein the electrospinning nozzle has an axis perpendicular to a length of the electrospun fiber.
4. The system according to claim 1 , further comprising:
a collection compartment configured to receive the transported electrospun fiber, wherein the collection compartment defines a plane that is parallel or normal to the axis of the electrospinning nozzle.
5. The system according to claim 1 , wherein the first conductive collection surface and the second conductive collection surface are endless travelling belts.
6. The system according to claim 1 , wherein at least one applies:
(a) a first portion of the first conductive collection surface and a first portion of the second conductive collection define an area in between that includes the deposition area;
(b) the second portion of the first conductive collection surface and the second portion of the second conductive collection define an area in between that includes the deposition area.
7. The system according to claim 1 , further comprising a collection rack disposed inside a collection compartment for removing a fiber from the first conductive collection surface.
8. The system according to claim 1 , further comprising a first roller configured to adjust elongation of the first portion of the first conductive collection surface and a second roller configured to adjust elongation of the first portion of the second conductive collection surface.
9. A method of forming an array of nanofibers, comprising:
electrospinning a fiber from an electrospinning nozzle;
attaching, in a deposition area, a first end of the electrospun fiber to a first conductive collection surface and a second end of the electrospun fiber to a second conductive collection surface, wherein:
the first conductive collection surface further comprises a first proximate end and a first distal end and the second conductive collection surface is positioned facing the first conductive collection surface, the second conductive surface further comprises a second proximate end and a second distal end;
the first proximate end and the second proximate end define a proximate gap between the first proximate end and the second proximate end;
the first distal end and the second distal end define a distal gap between the first distal end and the second distal end;
the first proximate end and the second proximate end further define the deposition area positioned within the proximate gap; and
a first portion of the first conductive collection surface and a first portion of the second conductive collection surface are further positioned to define a track angle θ;
transporting the electrospun fiber distally away from the deposition area; and
modifying, during the transport, a length of the electrospun fiber based at least in part on a difference between the length of the proximate gap and the length of the distal gap.
10. The method according to claim 9 , wherein the electrospinning nozzle has an axis perpendicular to the length of the fiber.
11. The method according to claim 9 , wherein at least one applies:
(a) the first portion of the first conductive collection surface and the first portion of the second conductive collection surface are aligned to each other and forming two opposing sides of an isosceles trapezoid;
(b) a second portion of the first conductive collection surface and a second portion of the second conductive collection surface are parallel to each other.
12. The method according to claim 9 , further comprising removing the electrospun fiber from the first and second collection surfaces to a collection rack disposed inside a collection compartment.
13. The method according to claim 9 , further comprising adjusting a geometry of the first portion of the first conductive collection surface via a first roller and a geometry of the first portion of the second conductive collection surface via a second roller.