EP-4735557-A2 - QUANTUM DOT SYNTHESIS USING PLASTICIZERS AND THEIR USE IN POLYMERIC COMPOSITIONS

Abstract

The present invention relates to a composition including quantum dots; a polymer; and, a plasticizer material, the plasticizer material providing dispersion of the quantum dots throughout the polymer whereby the composition is characterized as having lower haze and/or longer durability than a similar composition of quantum dots in the polymer in the absence of the plasticizer.

Inventors

• MCDANIEL, HUNTER
• RAMASAMY, KARTHIK
• DEY, MAHARSHI
• PARAMESWAR, Ashray Venkat

Assignees

• Ubiqd Inc.

Dates

Publication Date

20260506

Application Date

20240628

Claims (1)

1. WHAT IS CLAIMED IS: 1. A solid composition including: fluorescent quantum dots; a polymer; and, a plasticizer material capable of providing dispersion of the quantum dots throughout the polymer. 2. The composition of claim 1, wherein said composition is characterized as having haze less than 5%. 3. The composition of claim 1, wherein said composition is characterized as maintaining its level of fluorescence within 80% of its initial value over one year of sunlight exposure. 4. The composition of claim 1, wherein said polymer is extruded. 5. The composition of claim 1, wherein said polymer is a thermoplastic polymer. The composition of claim 1, wherein said polymer is selected from the group consisting of ethylene vinyl acetate (EVA), polyvinyl butyal (PVB), ethylene vinyl alcohol (EVOH), low density polystyrene (LDPS), nylon, polyethylene (PE), polyamide (PA), thermoplastic polyurethane (TPU), maleic anhydride grafted polyethylene (PE-MAH), maleic anhydride grafted ethylene vinyl acetate (EVA-MAH), polyolefin (POE), ionomers, polyvinyl difluoride (PVDF) or a mixture thereof. 7. The composition of claim 1, wherein said polymer further includes acrylate monomer, a styrene-butadiene copolymer, and a photoinitiator. 8. The composition of claim 1, wherein said plasticizer is selected from the group consisting of phthalates, terephthalates, adipates, sebacates, glycolates, dipropylene glycol dibenzoate, octadecene, tetradecene, dodecene, tetradecane, dodecane, dioctyl terephthalate, diisodecyl phthalate, bis(ethylhexyl) adipate, dipropylene glycol dibenzoate, 1-octadecene, 2,2'-Ethylenedioxydiethyl bis(2-ethylhexanoate), bis(ethylhexyl) sebacate, and combinations thereof. 9. The composition of claim 1, wherein said quantum dots comprise a material selected from the group consisting of CuInS2, CuInSe2, CuAlS2, CuAlSe2, CuInGaS2, CuInZnSe2, 26 LEGAL02/44543790v1 CuInSexS2-x, CuIn(Se,S)2, CuInZn(Se,S)2, AgInS2, AgInSe2, AgIn(Se,S)2, ZnS, ZnSe, CdS, CdSe, and combinations thereof. 10. The composition of claim 1, wherein said plasticizer is selected from the group consisting of poly(maleic anhydride-1-alt-octadecene), poly(isobutylene-alt- maleic anhydride), poly(ethylene-alt- maleic anhydride), polypropylene-graft-maleic anhydride, poly(sodium 4-styrenesulfonate), poly(potassium 4-styrenesulfonate), poly(ammonium 4- styrenesulfonate), (2-Dodecen-1-yl) succinic anhydride, polyethylene glycol(PEG) monooleate, polyethylene glycol(PEG) dioleate, polyethylene glycol(PEG) distearate, and combinations thereof. 11. A liquid composition including: fluorescent quantum dots, each comprising of at least one semiconductor core and at least one semiconductor shell material; and, a liquid plasticizer material capable of providing dispersion of the quantum dots throughout a polymer matrix such that the composition of quantum dot and plasticizer in combination with the polymer matrix is characterized by haze of less than 5% in comparison to a composition of quantum dots in the polymer matrix in the absence of the plasticizer. 12. The composition of claim 11, wherein said semiconductor cores comprise a material selected from the group consisting of CuInS 2 , CuInSe 2 , CuAlS 2 , CuAlSe 2 , CuInGaS 2 , CuInZnSe2, CuInSexS2-x, CuIn(Se,S)2, CuInZn(Se,S)2, AgInS2, AgInSe2, and AgIn(Se,S)2, and combinations thereof. 13. The composition of claim 11, wherein said semiconductor shell material is ZnS, ZnSe, GaS, GaSe, CdS, CdSe, or combinations thereof. 14. The composition of claim 11, wherein said plasticizer is selected from the group consisting of phthalates, terephthalates, adipates, sebacates, glycolates, dipropylene glycol dibenzoate, octadecene, tetradecane, dodecane, tetradecane, dodecane, and combinations thereof. 15. The composition of claim 11, wherein said plasticizer is selected from the group consisting of dioctyl terepthalate, diisodecyl phthalate, bis(ethylhexyl) adipate, dipropylene glycol 27 LEGAL02/44543790v1 dibenzoate, 1-octadecene, 2,2'-Ethylenedioxydiethyl bis(2-ethylhexanoate) and bis(ethylhexyl) sebacate. 16. The composition of claim 11, wherein said plasticizer is a compatibilizing agent is selected from the group of poly(maleic anhydride-1-alt-octadecene), poly(isobutylene-alt- maleic anhydride), poly(ethylene-alt- maleic anhydride), polypropylene-graft-maleic anhydride, poly(sodium 4-styrenesulfonate), poly(potassium 4-styrenesulfonate), poly(ammonium 4- styrenesulfonate), (2-Dodecen-1-yl) succinic anhydride, polyethylene glycol(PEG) monooleate, polyethylene glycol(PEG) dioleate, polyethylene glycol(PEG) distearate, and combinations thereof. 17. The composition of claim 11, further including an extrudable polymeric material selected from the group consisting of ethylene vinyl acetate (PVAc), polyvinyl butyal (PVB), ethylene vinyl alcohol (EVOH), nylon, low density polystyrene (LDPS), polyethylene (PE), polyamide(PA), thermoplastic polyurethane(TPU), maleic anhydride grafted polyethylene, maleic anhydride grafted ethylene vinyl acetate, polyolefin, polyvinyl difluoride (PVDF), and combinations thereof. 18. A process of preparing a core-shell quantum dot and plasticizer mixture comprising: precursors for a quantum dot core at temperatures and for times sufficient to form a resultant quantum dot core; and, admixing the resultant quantum dot core with a combination of both (a) precursors for a shell about the quantum dot core and (b) a plasticizer material capable of providing dispersion of resultant core-shell quantum dots into polymer matrixes to form a core-shell quantum dot/plasticizer mixture. 19. The process of claim 18 further comprising: admixing the core-shell quantum dot/plasticizer mixture with a solvent selected from among tetradecene, dodecene, and octadecene. 20. The process of claim 18, wherein said plasticizer is selected from the group consisting of phthalates, terephthalates, adipates, sebacates, glycolates, dioctyl terephthalate, diisodecyl phthalate, bis(ethylhexyl) adipate, dipropylene glycol dibenzoate, 2,2'- 28 LEGAL02/44543790v1 ethylenedioxydiethyl bis(2-ethylhexanoate), bis(ethylhexyl) sebacate, tetradecene, dodecene, tetradecane, dodecane, and octadecene, and combinations thereof. 29 LEGAL02/44543790v1

Description

QUANTUM DOT SYNTHESIS USING PLASTICIZERS AND THEIR USE IN POLYMERIC COMPOSITIONS CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Application No.63/511,236, filed June 30, 2023, the content of which is incorporated by reference herein in its entirety. FIELD OF THE DISCLOSURE The present invention is initially directed to: a composition including quantum dots; a polymer; and, a plasticizer material. The plasticizer materials are generally included to adjust the viscosity of the polymer compositions to make them more flexible, less brittle and generally more processable. Plasticizers with or without other solvents provide dispersion of the quantum dots throughout the polymer whereby the composition is characterized as having lower haze and/or longer durability than a similar composition of quantum dots in the polymer in the absence of the plasticizer with or without another solvent. The present invention is further directed to: a composition including quantum dots, each comprised of at least one semiconductor core and at least one semiconductor shell; and, a plasticizer material. The plasticizer materials can provide dispersion of the fluorophore particles throughout a polymer matrix such that a composition of fluorophore particles and plasticizer in combination with a polymer matrix is characterized by lower haze and/or longer durability than a similar composition of fluorophore particles in the polymer matrix in the absence of the plasticizer. Also, the present invention is directed at a process of preparing a core-shell quantum dot and plasticizer mixture comprising: admixing precursors for a quantum dot core at temperatures and for times sufficient to form a resultant quantum dot core; and, admixing the resultant quantum dot core with a combination of both (a) precursors for a shell about the quantum dot core and (b) a plasticizer material to form a core-shell quantum dot/plasticizer mixture. This admixture is capable of providing dispersion of resultant core-shell quantum dots into subsequent polymer matrixes. 1 LEGAL02/44543790v1 BACKGROUND OF THE DISCLOSURE Commodity and specialty polymeric systems are generally processed through well-known methods such as extrusion, injection molding, thermoforming and blow molding. Newer technologies such as 3D printing also serve as highly useful processing technologies to develop versatile polymeric and nanocomposite systems and are gaining extensive industrial and academic use. In order to improve the compatibility between inorganic nanoparticles and processable polymeric systems, improving processibility via plasticization by compatibilizing agents is considered essential. Conventionally, colloidal quantum dots (QDs) are synthesized using high boiling solvents and capping agents. The QDs are isolated from their reaction mixture by precipitation and redispersion methods and then the QD surface is treated with compatibilizing agents or ligands for their use in polymers. In general, QDs are isolated by precipitation and redispersion methods, in which, anti- solvent (polar solvent) is added to the mixture that coagulates quantum dots and the coagulated quantum dots are precipitated by centrifugation process. Further, the QDs are redispersed in non- polar solvent, and again coagulated and precipitated by adding polar solvent and centrifugation. This process is repeated several more times or until the desired purity is achieved. This process is solvent and labor intense and generates plenty of hazardous waste and it is difficult to scale-up. Importantly, in this process ligands may be removed or ripped off of the QD surface, which reduces the photoluminescence quantum yield and long-term stability and can make the dots difficult to dissolve in monomer solutions for polymer processing. The compositions and approaches described herein can overcome some of the prior challenges and provide the improved resultant compositions. BRIEF DESCRIPTION OF THE DRAWINGS Fig.1 shows a picture of visible emitting CuInS2/ZnS quantum dots in phthalate, sebacate, adipate and terephalate plasticizers (Examples 1-4). Fig. 2 shows a plot of absorption spectra of CuInS2/ZnS QDs in different dispersion medium (Examples 1-4 Isolation methods A-C). 2 LEGAL02/44543790v1 Fig. 3 shows a picture of extruder set-up showing liquid injection of QDLC and extruded QD strand (Examples 10-24). Fig.4 shows a picture of visible emitting CuInS2/ZnS quantum dots in phthalate, octadecene and sebacate at 80% QD loading (Examples 5-9). Fig.5 shows a picture of extruded (a) QDs strands in ethylene vinyl acetate (EVA), extruded using QDs dispersed in octadecene (Example 15), (b) QDs pellets in ethylene vinyl alcohol (EVOH) extruded using QDs dispersed in sebacate plasticizer (Example 16), and (c) a picture of a blown film in EVA. Fig 6 shows photostability data of CuInS2/ZnS QDs in EVOH films extruded using (1) powder QD, (2) QDs in sebacate plasticizer, and (3) 7.4% QD loading