Non-isocyanate polyurethane acrylate flexible ionic conductive elastomer and preparation method thereof

Abstract

The invention provides a non-isocyanate polyurethane acrylate-based flexible ionic conductive elastomer and a preparation method thereof, and relates to the field of ionic conductive flexible materials. The main components of the flexible ionic conductive elastomer are non-isocyanate urethane acrylate, an active diluent, a photoinitiator, a lithium salt and an additive. By adopting the method provided by the invention, the non-isocyanate polyurethane acrylate flexible ionic conductive elastomer which has a wide temperature application range and does not contain any liquid is successfully prepared. The flexible ionic conductive elastomer is free of toxic monomers in the preparation process, has a wide temperature application range, can be used at the temperature of 0-80 DEG C, does not contain any liquid after being cured, and cannot cause liquid leakage due to extrusion.

Description

Technical Field

[0001] The invention relates to the field of ion conductive flexible materials, and in particular to a non-isocyanate polyurethane acrylate-based flexible ion conductive elastomer and a preparation method thereof. Background Art

[0002] Conductive flexible materials are the core components of flexible sensors. In the early days, conductive fillers and conductive particles were mostly added to obtain electronic conductive flexible materials. However, this material has problems such as uneven filler distribution and conductor short circuit under high stress, which limits its application in the field of flexible sensors. Ionic conductive flexible materials solve these problems by accommodating freely moving ions through a cross-linked network, and have the advantages of high transparency and high flexibility. Ionic conductive flexible materials mainly include hydrogels, ion gels, flexible ion conductive elastomers, etc. Hydrogels are poor in mechanical strength and flexibility, and are easy to freeze at low temperatures and dehydrate at high temperatures, which limits their application environment; ion gels have the problem that ionic liquids are easy to leak when squeezed. Flexible ion conductive elastomers solve the problems of the above materials because they do not contain liquid and have high stability. They have a wide operating temperature window, good flexibility, and will not leak when squeezed.

[0003] Polyurethane acrylate is an important photocurable resin, which contains acrylic functional groups and urethane bonds in its molecules, so that it has excellent flexibility, wear resistance, adhesion and low temperature resistance after curing, so it can be used to prepare flexible ion conductive elastomers. Usually, the preparation of polyurethane acrylate requires the use of monomers containing isocyanates, such as diphenylmethane diisocyanate and hexamethylene diisocyanate. However, the isocyanate group is highly toxic and harmful to the environment and human body. Therefore, this patent uses monomers that do not contain isocyanates to prepare polyurethane acrylate. A non-isocyanate polyurethane is prepared by a synthetic method in which ethylene carbonate and diamine are reacted to produce urethane diol and then an ester exchange reaction is carried out with a polyol, and then a non-isocyanate polyurethane is reacted with an acrylic anhydride compound to synthesize a non-isocyanate polyurethane acrylate.

[0004] According to the above, a non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer was prepared. Summary of the invention

[0005] In view of the above situation, the purpose of the present invention is to provide a non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer and a preparation method thereof, wherein the flexible ion-conductive elastomer has a wide temperature use range, does not contain any liquid, and does not use toxic isocyanates during the preparation process.

[0006] A method for preparing a non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer comprises the following preparation steps:

[0007] Step 1: Add ethylene carbonate and aliphatic diamine into a flask, react at 80°C to 120°C for 4 to 6 hours at a rotation speed of 200 r / min, and then recrystallize with deionized water to obtain urethane diol.

[0008] Step 2: Add urethane diol, polycarbonate diol or polyether diol with a molecular weight of 400 to 5000 into a flask, mix well at 100° C., and react at 180° C. in vacuum (pressure less than 500 Pa) at a speed of 200 r / min for 1 hour to obtain non-isocyanate polyurethane.

[0009] Step 3: Add acrylic anhydride compounds, triethylamine, inhibitors, and catalysts to the non-isocyanate polyurethane obtained in step 2, mix well in a solvent, and react at room temperature for 48 hours at a speed of 200 r / min. After purification, bake in a vacuum oven at 80° C. for 24 hours to remove the solvent, and obtain the reaction product, non-isocyanate polyurethane acrylate.

[0010] Step 4: Add the active diluent, photoinitiator, lithium salt and additives to the non-isocyanate polyurethane acrylate obtained in step 3, stir at room temperature for 1 hour at a speed of 200 r / min to mix evenly, and obtain the final product, a flexible ion conductive elastomer precursor solution, and then perform photopolymerization reaction under 3W ultraviolet light to obtain a flexible ion conductive elastomer.

[0011] To further supplement the above steps:

[0012] In step 1, the molar mass ratio of ethylene carbonate to aliphatic diamine is 2 to 2.5: 1. The aliphatic diamine includes one or more of 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, isophoronediamine, and 4,4-diaminodicyclohexylmethane.

[0013] The molar mass ratio of the urethane diol to the medium molecular weight diol in step 2 is 2 to 7: 1. The polycarbonate diol and the polyether diol include one or more of polypropylene carbonate diol, polyethylene carbonate diol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

[0014] In step 3, the mass ratio of non-isocyanate polyurethane, solvent, acrylic anhydride compound, triethylamine, inhibitor, and catalyst is 50:40:(4-8):(2-6):0.1:0.1. The acrylic anhydride compound includes one or more of acrylic anhydride and methacrylic anhydride; the solvent is one or more of N,N-dimethylformamide and dichloromethane; the inhibitor is one or more of hydroquinone p-hydroxyanisole; and the catalyst is 4-dimethylaminopyridine.

[0015] The mass ratio of non-isocyanate polyurethane acrylate, reactive diluent, photoinitiator, lithium salt and additive in step 4 is (15-65): (15-65): (2-4): (5-15): (10-20). The reactive diluent includes one or more of isobornyl methacrylate, isobornyl acrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate, 1,6-hexanediol diacrylate, diethylene glycol ethyl ether acrylate and trimethylolpropane triacrylate. The photoinitiator is one or more of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2-hydroxymethylphenylpropane-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone, dibenzophenone, 2-phenyl-2,2-dimethylamino-1-(4-morpholinephenyl)-1-butanone and 1-hydroxycyclohexylphenylpropiophenone. The lithium salt is one or more of lithium bis(trifluoromethanesulfonyl)imide, lithium bis(fluorosulfonyl)imide and lithium perchlorate. The additive is one or more of succinonitrile, tributyl citrate and fumed silica.

[0016] Beneficial effects:

[0017] The present invention uses ethylene carbonate and aliphatic diamine to ring-opening reaction to obtain an urethane diol, and then carries out ester exchange reaction with diol to obtain non-isocyanate polyurethane, and finally carries out esterification reaction with acrylic anhydride compound to obtain non-isocyanate polyurethane acrylate. The synthesis process of the non-isocyanate polyurethane acrylate does not use highly toxic chemicals and high-cost materials, saves energy and reduces emissions, is green and environmentally friendly, and can be used to prepare flexible ion conductive elastomers. After adding active diluents, photoinitiators, lithium salts, and additives to the non-isocyanate polyurethane acrylate, ultraviolet light curing can be used to prepare a non-liquid having good ionic conductivity (2.7×10 -3 ~4.1×10 -3 S / m), high flexibility (tensile strength <1.5MPa, elongation at break>200%), high transparency (visible light transmittance>80%), wide temperature range (0℃~80℃), liquid-free flexible ion conductive elastomer, and can be used in the fields of flexible sensors and electrolytes. DETAILED DESCRIPTION

[0018] The following examples are provided for a better understanding of the present invention, but are not intended to limit the best mode of implementation, nor to limit the content and protection scope of the present invention. Any product identical or similar to the present invention obtained by anyone under the inspiration of the present invention or by combining the features of the present invention with other prior arts shall fall within the protection scope of the present invention.

[0019] Example 1

[0020] This embodiment provides a non-isocyanate polyurethane acrylate, and the preparation method is as follows:

[0021] Step 1: Add 73.92g of ethylene carbonate (EC) and 46.4g of 1,6-hexanediamine (1,6-HDA) into a flask, react at 100°C for 6h at a speed of 200r / min, then add 120g of deionized water into the flask, mix at 80°C for 30min at a speed of 200r / min, and dry the product after two recrystallizations to obtain the final product, urethane diol (ECUD).

[0022] Step 2: Add 10 g of urethane diol (ECUD) and 42.8 g of polypropylene carbonate diol (PPCD) into a flask and mix well. React at a speed of 200 r / min and 180° C. in vacuum (pressure less than 500 Pa) for 1 h to obtain non-isocyanate polyurethane (NIPU).

[0023] Step 3: Add 50 g of the non-isocyanate polyurethane obtained in step (2) into a flask and mix evenly with 40 g of N,N-dimethylformamide (DMF), add 0.1 g of hydroquinone (HQ), 0.1 g of 4-dimethylaminopyridine (DMAP), 4.53 g of triethylamine (HEA), and 5.92 g of methyl acrylic anhydride (MAAH), mix evenly, react at room temperature at a speed of 200 r / min for 48 hours, and then purify and bake in a vacuum oven at 80°C for 24 hours to remove the solvent to obtain the reaction product, non-isocyanate polyurethane acrylate (NIPUA).

[0024] Example 2

[0025] This embodiment provides a flexible ion conductive elastomer, and the preparation method is as follows:

[0026] (1) 14 g of non-isocyanate polyurethane acrylate (NIPUA) and 6 g of hydroxyethyl acrylate (HEMA) were added to a beaker, mixed at 200 r / min and 60° C. for 1 h, and then 0.8 g of photoinitiator 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) was added and stirred for 30 min to obtain a photosensitive resin.

[0027] (2) 5 g of the photosensitive resin obtained in step (1) was added to a beaker, and 0.6 g of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and 1.25 g of succinonitrile (SN) were added, followed by ultrasonication for 30 min to mix the liquid evenly, thereby obtaining a flexible ion conductive elastomer precursor solution.

[0028] (3) Pour the precursor solution prepared in step (2) into a rectangular strip of polytetrafluoroethylene mold (size 60×10×1 mm 3), use ultraviolet light with a wavelength of 365nm and a power of 3W to irradiate the solution for 5 minutes to carry out photopolymerization reaction to obtain a flexible ion conductive elastomer.

[0029] Example 3

[0030] This embodiment provides a flexible ion conductive elastomer, and the preparation method is as follows:

[0031] (1) 10 g of non-isocyanate polyurethane acrylate (NIPUA) and 10 g of hydroxyethyl acrylate (HEMA) were added to a beaker, mixed at 200 r / min and 60° C. for 1 h, and then 0.8 g of photoinitiator 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) was added and stirred for 30 min to obtain a photosensitive resin.

[0032] (2) 5 g of the photosensitive resin obtained in step (1) was added to a beaker, and 0.6 g of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and 1.25 g of succinonitrile (SN) were added, followed by ultrasonication for 30 min to mix the liquid evenly, thereby obtaining a flexible ion conductive elastomer precursor solution.

[0033] (3) Pour the precursor solution prepared in step (2) into a rectangular strip of polytetrafluoroethylene mold (size 60×10×1 mm 3 ), use ultraviolet light with a wavelength of 365nm and a power of 3W to irradiate the solution for 5 minutes to carry out photopolymerization reaction to obtain a flexible ion conductive elastomer.

[0034] Example 4

[0035] This embodiment provides a flexible ion conductive elastomer, and the preparation method is as follows:

[0036] (1) 6 g of non-isocyanate polyurethane acrylate (NIPUA) and 14 g of hydroxyethyl acrylate (HEMA) were added to a beaker, mixed at 200 r / min and 60° C. for 1 h, and then 0.8 g of photoinitiator 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) was added and stirred for 30 min to obtain a photosensitive resin.

[0037] (2) 5 g of the photosensitive resin obtained in step (1) was added to a beaker, and 0.6 g of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and 1.25 g of succinonitrile (SN) were added, followed by ultrasonication for 30 min to mix the liquid evenly, thereby obtaining a flexible ion conductive elastomer precursor solution.

[0038] (3) Pour the precursor solution prepared in step (2) into a rectangular strip of polytetrafluoroethylene mold (size 60×10×1 mm 3), use ultraviolet light with a wavelength of 365nm and a power of 3W to irradiate the solution for 5 minutes to carry out photopolymerization reaction to obtain a flexible ion conductive elastomer.

[0039] Example 5

[0040] This embodiment provides a flexible ion conductive elastomer, and the preparation method is as follows:

[0041] (1) 10 g of non-isocyanate polyurethane acrylate (NIPUA) and 10 g of hydroxyethyl acrylate (HEMA) were added to a beaker, mixed at 200 r / min and 60° C. for 1 h, and then 0.8 g of photoinitiator 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) was added and stirred for 30 min to obtain a photosensitive resin.

[0042] (2) 5 g of the photosensitive resin obtained in step (1) was added to a beaker, and 0.45 g of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and 1.25 g of succinonitrile (SN) were added, followed by ultrasonication for 30 min to mix the liquid evenly, thereby obtaining a flexible ion conductive elastomer precursor solution.

[0043] (3) Pour the precursor solution prepared in step (2) into a rectangular strip of polytetrafluoroethylene mold (size 60×10×1 mm 3 ), use ultraviolet light with a wavelength of 365nm and a power of 3W to irradiate the solution for 5 minutes to carry out photopolymerization reaction to obtain a flexible ion conductive elastomer.

[0044] Example 6

[0045] This embodiment provides a flexible ion conductive elastomer, and the preparation method is as follows:

[0046] (1) 10 g of non-isocyanate polyurethane acrylate (NIPUA) and 10 g of hydroxyethyl acrylate (HEMA) were added to a beaker, mixed at 200 r / min and 60° C. for 1 h, and then 0.8 g of photoinitiator 2,4,6-trimethylbenzoyl-diphenylphosphine oxide (TPO) was added and stirred for 30 min to obtain a photosensitive resin.

[0047] (2) 5 g of the photosensitive resin obtained in step (1) was added to a beaker, and 0.75 g of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) and 1.25 g of succinonitrile (SN) were added, followed by ultrasonication for 30 min to mix the liquid evenly, thereby obtaining a flexible ion conductive elastomer precursor solution.

[0048] (3) Pour the precursor solution prepared in step (2) into a rectangular strip of polytetrafluoroethylene mold (size 60×10×1 mm 3), use ultraviolet light with a wavelength of 365nm and a power of 3W to irradiate the solution for 5 minutes to carry out photopolymerization reaction to obtain a flexible ion conductive elastomer.

[0049] The performance test results of Examples 2 to 6 are shown in the table, see Table 1 for details.

[0050] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

[0051] Table 1 Room temperature performance test of non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer

[0052]

[0053] Table 2 Performance test of Example 3 at different temperatures

[0054]

Claims

1. A non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer, characterized in that: The raw material components include the following parts by weight: 15-65 parts of non-isocyanate polyurethane acrylate, 15-65 parts of active diluent, 2-4 parts of photoinitiator, 5-15 parts of lithium salt, and 10-20 parts of additives.

2. The non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer according to claim 1, characterized in that: The active diluent is one or more of isobornyl methacrylate, isobornyl acrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate, 1,6-hexanediol diacrylate, diethylene glycol ethyl ether acrylate, and trimethylolpropane triacrylate; the photoinitiator is one or more of 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, 2-hydroxymethylphenylpropane-1-one, 2-methyl-1-(4-methylthiophenyl)-2-morpholine-1-propanone, dibenzophenone, 2-phenyl-2,2-dimethylamino-1-(4-morpholinephenyl)-1-butanone, and 1-hydroxycyclohexylphenylpropiotone; the lithium salt is one or more of lithium bistrifluoromethanesulfonyl imide, lithium bisfluorosulfonyl imide, and lithium perchlorate; and the additive is one or more of succinonitrile, tributyl citrate, and fumed silica.

3. A method for preparing the non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer according to claim 1 or 2, characterized in that: The method comprises the following preparation steps: Step 1: Add ethylene carbonate and aliphatic diamine into a flask, react at 80°C to 120°C for 4 to 6 hours at a speed of 200 r / min, and then recrystallize with deionized water to obtain urethane diol; Step 2: adding urethane diol, polycarbonate diol or polyether diol with a molecular weight of 400 to 5000 into a flask, mixing them evenly at 100° C., and then reacting them in vacuum at 180° C. for 1 hour at a speed of 200 r / min to obtain non-isocyanate polyurethane; Step 3: adding acrylic anhydride compound, triethylamine, polymerization inhibitor and catalyst to the non-isocyanate polyurethane obtained in step 2, mixing them evenly in a solvent, reacting them at room temperature for 48 hours at a speed of 200 r / min, and then drying them in a vacuum oven at 80° C. for 24 hours to remove the solvent, thereby obtaining a reaction product, non-isocyanate polyurethane acrylate; Step 4: Add the active diluent, photoinitiator, lithium salt and additives to the non-isocyanate polyurethane acrylate obtained in step 3, stir at room temperature for 1 hour at a speed of 200 r / min to mix evenly, and obtain the final product, a flexible ion conductive elastomer precursor solution, and then perform photopolymerization reaction under 3W ultraviolet light to obtain a flexible ion conductive elastomer.

4. The method for preparing the non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer according to claim 1 or 2, characterized in that : In step 1, the molar mass ratio of ethylene carbonate to aliphatic diamine is 2 to 2.5:1; the aliphatic diamine includes one or more of 1,4-butanediamine, 1,5-pentanediamine, 1,6-hexanediamine, isophoronediamine, and 4,4-diaminodicyclohexylmethane.

5. The method for preparing a non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer according to claim 1 or 2, characterized in that : In step 2, the molar mass ratio of the urethane diol to the medium molecular weight diol is 2 to 7:1; the polycarbonate diol and the polyether diol include one or more of polypropylene carbonate diol, polyethylene carbonate diol, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol.

6. The method for preparing the non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer according to claim 1 or 2, characterized in that : In step 3, the mass ratio of non-isocyanate polyurethane, solvent, acrylic anhydride compound, triethylamine, inhibitor and catalyst is 50:40:(4-8):(2-6):0.1:0.1; the acrylic anhydride compound includes one or more of acrylic anhydride and methacrylic anhydride; the solvent is one or more of N,N-dimethylformamide and dichloromethane; the inhibitor is one or more of hydroquinone and p-hydroxyanisole; and the catalyst is 4-dimethylaminopyridine.

7. The method for preparing a non-isocyanate polyurethane acrylate-based flexible ion-conductive elastomer according to claim 1 or 2, characterized in that : The mass ratio of the non-isocyanate polyurethane acrylate, reactive diluent, photoinitiator, lithium salt and additive in step 4 is (15-65): (15-65): (2-4): (5-15): (10-20).

Images