Thermal amplification of free radical polymerization induced by red to near-infrared irradiation

Patent metadata

Field	Value
Publication number	US-11384167-B2
Application number	US-201816770342-A
Country	US
Kind code	B2
Filing date	Dec 20, 2018
Priority date	Dec 21, 2017
Publication date	Jul 12, 2022
Grant date	Jul 12, 2022

Abstract

The present invention relates to compositions thermally curable on demand by red to near infrared irradiation, method of using same for thermal amplification of free radical polymerizations, and articles obtained by such method. The invention also relates to the use of a heat-generating dye in association with a thermal initiator for controlling the onset of thermal free radical polymerization.

First claim

The invention claimed is:

1. A composition thermally curable on demand under the triggering action of red to near-infrared light-emitting diode (LED) irradiation of intensity<10 W/cm 2 comprising:
(a) <0.50 w/w of the total weight of the composition of at least one heat-generating dye that generates heat when exposed to red to near-infrared LED irradiation of intensity<10 W/cm 2 ;
(b) at least one thermal initiator; and
(c) at least one polymerizable component comprising a C═C bond polymerizable by free radical polymerization;
wherein the at least one thermal initiator undergoes homolytic cleavage to generate two free radicals upon exposure to heat generated in the composition, without electron transfer from the dye.

2. The composition according to claim 1 , wherein the at least one polymerizable component is selected from monomers, prepolymers, dimers, trimers or oligomers containing at least one C═C bond that is conjugated with an aryl moiety, a carboxyl group, or another double bond.

3. The composition according to claim 1 , wherein the at least one heat-generating dye is selected from

4. The composition according to claim 1 , wherein the at least one thermal initiator is selected from:

5. A composition dually curable photochemically and thermally on demand under the triggering action of red to near-infrared light-emitting diode (LED) irradiation of intensity<10 W/cm 2 comprising:
(a) <0.50 w/w of the total weight of the composition, of at least one heat-generating dye that generates heat and is additionally an electron donor when exposed to red to near-infrared LED irradiation of intensity<10 W/cm 2 ;
(b) at least one thermal initiator;
(c) at least one polymerizable component comprising a C═C bond polymerizable by free radical polymerization;
(d) an onium salt, and optionally:
(e) a reducing agent suitable for regenerating the dye; and/or an oxygen scavenger;
wherein the at least one thermal initiator undergoes homolytic cleavage to generate two free radicals upon exposure to the heat generated in the composition, without accepting an electron from the dye.

6. The composition according to claim 5 , wherein the onium salt is of formula ((R A ) 2 I + X A − or (R A ) 3 S + X A − ; wherein each occurrence of R A independently represents a C 6-10 aryl or a C 1-10 alkyl moiety; wherein the aryl moiety is optionally, individually, further substituted with one or more linear or branched C 1-6 alkyl or C 6-10 aryl moieties; and wherein X A − represents a counter ion.

7. The composition according to claim 5 , wherein the onium salt is:

8. The composition according to claim 5 , wherein the reducing agent c) and the oxygen scavenger d) are one and the same compound.

9. The composition according to claim 5 , wherein the reducing agent is selected from:
4-(diphenylphosphino)benzoic acid (4-dppba), 2-diphenylphosphinobenzoic acid (2-dppba), bis(2-diphenylphosphinophenyl)-ether (2-dpppe), triomethoxyphenylphosphine (triompp), DPBP bidentate phosphine (DPBP), 4-dimethylaminophenyldiphenylphosphine (4-dmapdp), (R,R) dach phenyl trost (trost), and triphenylphosphine (tpp)); and
Ethyl 4-dimethylaminobenzoate (EDB), 4-(dimethylamino)phenylacetic acid (ADP), triphenylamine (TPA), N,N-dibutylaniline (DBA), N-Ethyl-N-isopropylaniline (EIPA), and 3-(dimethylamino)benzyl alcohol (3-dmaba).

10. A process for preparing an article by thermal amplification of free radical polymerization comprising the step of exposing to red to near-infrared radiation of intensity<10 W/cm 2 a composition comprising at least one polymerizable component comprising a C═C bond polymerizable by free radical polymerization, in the presence of:
<0.50 w/w of at least one heat-generating dye that generates heat when exposed to red to near-infrared LED irradiation of intensity<10 W/cm 2 , and
at least one thermal initiator selected from peroxides, hydroperoxides, alkoxyamines, and azo compounds.

11. The process according to claim 10 , wherein at least one polymerizable component is an acrylate or methacrylate selected from HPMA, TMPTA, 1,4-BDMA, aliphatic, or an aromatic diurethane dimethacrylates that is UDMA, or mixtures thereof.

12. The process according to claim 10 , further comprising a step of mixing or impregnating composite reinforcements with said composition prior to red to near-infrared LED irradiation.

13. The process according to claim 12 , wherein the composite reinforcements are glass fibers, carbon fibers, aramid fibers, basalt fibers, silica fibers, polymer fibers, natural fibers, or a mixture thereof.

14. The process according to claim 10 , wherein crosslinking/curing of the composition occurs throughout the whole thickness of the composition.

15. The process according to claim 10 , carried out in the presence of oxygen.

16. An article obtained by a thermal amplification process according to claim 10 .

17. The composition according to claim 1 , at least one thermal initiator is selected from peroxides, hydroperoxides, alkoxyamines, and azo compounds.

18. The composition according to claim 2 , wherein the at least one polymerizable component is selected from acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid, maleic acid, and esters and amides thereof; styrene, ethylene, propylene, N-vinyl acrylamide, and N-vinylpyrolidone.

19. The composition according to claim 2 , wherein the at least one polymerizable component is selected from acrylates and methacrylates selected from HPMA, TMPTA, 1,4-BDMA; UDMA; and mixtures thereof.

20. A process for controlling the onset of thermal free radical polymerization of a composition comprising at least one polymerizable component comprising a C═C bond polymerizable by free radical polymerization, the process comprising
exposing the composition to red to near-infrared radiation of intensity<10 W/cm 2 in the presence of <0.10% w/w of at least one heat-generating dye that generates heat when exposed to red to near-infrared LED irradiation of intensity<10 W/cm 2 , in association with a thermal initiator selected from peroxides, hydroperoxides, alkoxyamines, and azo compounds, that generates a free radical upon exposure to the heat generated by the dye, without electron transfer from the dye.

21. The composition according to claim 1 , wherein the at least one heat-generating dye is selected from any one or more of the following:

22. The process of claim 10 , wherein the at least one thermal initiator is selected from alkoxyamines and azo compounds.

23. The process of claim 20 , wherein at least one thermal initiator is selected from alkoxyamines, and azo compounds.

Assignees

• Univ Haute Alsace
• Univ Aix Marseille
• Centre Nat Rech Scient

Inventors

• Bonardi Aude-Heloise
• Lalevee Jacques
• Morlet-Savary Fabrice
• Dietlin Celine
• Gigmes Didier
• Dumur Frederic

Classifications

• C08F2/46 Primary

  Polymerisation initiated by wave energy or particle radiation · CPC title

• C08K5/315

  Compounds containing carbon-to-nitrogen triple bonds · CPC title

• C08K3/30

  Sulfur-, selenium- or tellurium-containing compounds · CPC title

• C08F222/22

  Esters containing nitrogen · CPC title

• G03F7/029 Primary

  Inorganic compounds; Onium compounds; Organic compounds having hetero atoms other than oxygen, nitrogen or sulfur · CPC title