Olefin metathesis photopolymers
Described herein are compositions and methods for processing photopolymers based on olefin metathesis. The compositions and methods comprise latent ruthenium complexes and photoacids and/or photoacid generators.
1. A method for generating a polymer, comprising:
(a) providing a mixture comprising (i) a latent ruthenium (Ru) complex; (ii) an initiator that is an iodonium salt or a sulfonium salt; (iii) at least one polymer precursor; and (iv) an additive; and
(b) exposing said mixture to electromagnetic radiation to activate said initiator, wherein upon activation, said initiator reacts with said latent Ru complex to generate an activated Ru complex, which activated Ru complex reacts with said at least one polymer precursor to generate at least a portion of said polymer, wherein said additive is a compound having a structure represented by:
2. The method of claim 1 , wherein said electromagnetic radiation is emitted from a laser, a digital light processing (DLP) projector, a lamp, a light emitting diode (LED), a mercury arc lamp, a fiber optic, or a liquid crystal display (LCD).
3. The method of claim 1 , wherein said electromagnetic radiation is emitted at a wavelength of 350 nanometers (nm) to 465 nm.
4. The method of claim 1 , wherein said mixture is exposed to said electromagnetic radiation from 100 millijoules (mJ)/centimeters 2 (cm 2 ) to 1,000 mJ/cm 2 .
5. The method of claim 1 , wherein said mixture further comprises a sensitizer that sensitizes said initiator.
6. The method of claim 5 , wherein said sensitizer is configured to transfer or disperse the energy of electromagnetic radiation, thereby sensitizing said initiator.
7. The method of claim 5 , wherein said sensitizer is a conjugated aromatic molecule, a phenothiazine, a thioxanthone, a coumarin, an indoline, a porphyrin, a rhodamine, a pyrylium, a phenazine, a phenoxazine, an alpha hydroxy ketone, or a phosphine oxide.
8. The method of claim 5 , wherein said sensitizer is a compound selected from the group consisting of:
9. The method of claim 1 , wherein said latent Ru complex is a compound having a structure represented by:
10. The method of claim 1 , wherein said activated Ru complex undergoes a ring opening metathesis polymerization (ROMP) reaction with said at least one polymer precursor to generate said at least said portion of said polymer.
11. The method of claim 1 , wherein said at least one polymer precursor comprises one or more polymer precursor, each polymer precursor being independently selected from the group consisting of a dicyclopentadiene, a branched poly(dicyclopentadiene), a crosslinked poly(dicyclopentadiene), an oligomeric poly(dicyclopentadiene), a polymeric poly(dicyclopentadiene), a norbomene, an aliphatic olefin, a cyclooctene, a cyclooctadiene, a tricyclopentadiene, a polybutadiene, an ethylene propylene diene monomer (EPDM) rubber, a polypropylene, a polyethylene, a cyclic olefin polymer, and a diimide.
12. The method of claim 1 , wherein said sulfonium salt is a compound selected from the group consisting of
13. The method of claim 7 , wherein said iodonium salt is a compound selected from the group consisting of:
14. A method for printing a three-dimensional (3D) object, comprising:
(a) providing a resin comprising (i) a latent ruthenium (Ru) complex, (ii) an initiator, and (iii) at least one polymer precursor; and
(b) exposing said resin to electromagnetic radiation to activate said initiator, wherein upon activation, said initiator reacts with said latent Ru complex to generate an activated Ru complex, which activated Ru complex reacts with said polymer precursor to print at least portion of said 3D object,
wherein said 3D object has a pixel size from 100 nanometers (nm) to 200 micrometers (μm).
15. The method of claim 14 , wherein said 3D object is printed using additive manufacturing, stereolithography, computed axial lithography, ink jetting, sintering, vat photopolymerization, multiphoton lithography, holographic lithography, hot lithography, IR lithography, direct writing, masked stereolithography, drop-on-demand printing, polyjet, digital-light projection (DLP), projection micro-stereolithography, nanoimprint lithography, or photolithography.
16. The method of claim 14 , wherein (a) comprises providing a mixture comprising said resin, wherein said mixture further comprises a sensitizer that sensitizes said initiator.
17. The method of claim 16 , wherein said sensitizer is configured to transfer or disperse the energy of electromagnetic radiation, thereby sensitizing said initiator.
18. A method for printing a three-dimensional (3D) object, comprising:
(a) providing a resin comprising (i) a latent ruthenium (Ru) complex, (ii) an initiator, and (iii) at least one polymer precursor; and
(b) exposing said resin to electromagnetic radiation to activate said initiator, wherein upon activation, said initiator reacts with said latent Ru complex to generate an activated Ru complex, which activated Ru complex reacts with said polymer precursor to print at least portion of said 3D object, wherein said 3D object is printed on a window material.
19. The method of claim 18 , wherein said window material is permeable to oxygen and has a surface free energy of at most 37 millinewton (mN)/meter (m).
20. The method of claim 18 , wherein said window material comprises a transparent fluoropolymer.
21. The method of claim 14 , wherein said pixel size is from 5 m to 100 km.
22. The method of claim 18 , wherein (a) comprises providing a mixture comprising said resin, wherein said mixture further comprises a sensitizer that sensitizes said initiator.
23. The method of claim 22 , wherein said sensitizer is configured to transfer or disperse the energy of electromagnetic radiation, thereby sensitizing said initiator.
24. The method of claim 18 , wherein said 3D object is printed using additive manufacturing, stereolithography, computed axial lithography, ink jetting, sintering, vat photopolymerization, multiphoton lithography, holographic lithography, hot lithography, IR lithography, direct writing, masked stereolithography, drop-on-demand printing, polyjet, digital-light projection (DLP), projection micro-stereolithography, nanoimprint lithography, or photolithography.