A polyurethane polymer capable of light and heat dual curing, preparation method and composite material thereof

Abstract

The present invention discloses a polyurethane polymer capable of photothermal dual curing, a preparation method and a composite material thereof, wherein the polyurethane polymer capable of photothermal dual curing comprises the following components: an isocyanate component (A), an organic polyol component (B), an amine compound containing an active unsaturated bond (C), an active diluent (D), a curing agent component 1 (E), and a curing agent component 2 (F); a mixture of the polyurethane polymer and a reinforcing material is cured to prepare a corresponding composite material, wherein the curing method is photothermal dual curing. The polyurethane polymer has low water sensitivity, high curing efficiency and low TVOC, and the composite material based on the polyurethane polymer has excellent mechanical properties.

Description

Technical Field

[0001] The present invention relates to a photothermal dual-curable polyurethane polymer, a preparation method and a composite material thereof, and specifically to a photothermal dual-curable polyurethane polymer containing an active unsaturated bond end cap and a preparation method thereof, wherein the polyurethane polymer comprises an organic isocyanate, an organic polyol, an amine compound containing an active unsaturated bond, a curing agent component 1, a curing agent component 2, and an active diluent. Another aspect of the present invention relates to a polyurethane composite material, which is prepared by curing a mixture of a polyurethane polymer and a reinforcing material under photothermal conditions. Background Art

[0002] Polyurethane resin is a good thermosetting resin material. Because of its excellent fatigue resistance, good impact toughness, strong stability and chemical corrosion resistance, it is widely used in foaming materials, elastomers, adhesives, paving floors, waterproof materials, fibers, synthetic leather, water-based coatings and other types. It is widely used in oil pipelines, transportation, building insulation, textiles and clothing, medical equipment, sports equipment and other aspects.

[0003] A large number of isocyanate groups remain in the polyurethane resin material, and the high activity of the isocyanate groups leads to high water sensitivity and temperature sensitivity. Therefore, the storage conditions of polyurethane resin are relatively harsh, and its storage conditions are usually -5℃~25℃, and the sealing conditions of the packaging and the environmental humidity are required to be high, resulting in high storage and operation costs. At the same time, the high water sensitivity of polyurethane resin will cause the reaction system to absorb water, and its isocyanate group reacts with water to generate carbon dioxide gas, causing it to foam, affecting the appearance and performance of the product; at the same time, the absorption of water will accelerate the reaction speed, resulting in a short operating window, which is not conducive to its application in open systems that require a long operating cycle and complex temperature, humidity and environmental systems, such as prepregs, wind power pultrusion, doors and windows and other industries. The current method to solve the high water sensitivity of polyurethane resin is mainly to add small molecules that can absorb water, such as molecular sieves or zeolites, to the polyurethane polyol composition (industrially called white material) to reduce the moisture in the polyurethane reaction system; but small molecules such as molecular sieves and zeolites will increase the reactivity of the polyurethane reaction system over time, accelerate the reaction speed, and reduce the operating time, which is not conducive to the use of polyurethane resin.

[0004] CN105199075A discloses a polyurethane composite material that can be cured by free radicals initiated by heat, characterized in that an organic compound of (meth) hydroxyalkyl acrylate is added to the isocyanate reactive component, so that the reaction system simultaneously has free radical polymerization reaction and addition polymerization reaction of isocyanate group and hydroxyl group, which has the function of reducing the water sensitivity of polyurethane resin, but it still adopts the traditional process route of blending components A and B, and does not completely solve the problems of water sensitivity of polyurethane resin, such as polyurethane resin still has high water sensitivity during transportation, and strict requirements on transportation and storage conditions. In this patent, the curing method of the composite material still adopts high-temperature thermal curing, which has problems such as high energy consumption, low operational safety and low curing efficiency.

[0005] CN109666115B discloses an aminosilane-terminated modified polyurethane resin and a preparation method thereof, which is characterized in that aminosilane is used to perform secondary end-capping on an isocyanate-terminated prepolymer, and a molecular chain regulator is added to obtain an aminosilane-terminated modified polyurethane resin; the method is mainly used in the field of sealants, and the products are mainly thin products, which is not conducive to the use in the field of thick products, especially in the field of composite materials requiring high mechanical properties; at the same time, its molecular chain regulator mostly uses small molecules such as phenol, ethanol, and alcohol amine, which are highly volatile and have high TVOC.

[0006] In addition, in the compression molding process using unsaturated resins, amino resins or vinyl resins, a large amount of reactive small molecule monomers containing vinyl or amide groups, such as monofunctional organic small molecules such as styrene, acrylamide, diphenylene and methyl methacrylate, need to be used. In the compression molding process, the monofunctional organic small molecule monomers are not active enough to participate in the polymerization reaction. Therefore, they cannot fully participate in the polymerization reaction, resulting in a large number of small molecules being free from the polymer, thus becoming a source of VOC (volatile organic compounds), making the TVOC (total volatile organic compounds) value of the product high, endangering the health of users. Although CN 109734890A discloses a method for preparing unsaturated resins using hydroxyethyl / propyl methacrylate instead of styrene as an active diluent, the boiling point of hydroxyethyl / propyl methacrylate is higher than that of styrene to reduce VOC and TVOC emissions, but the boiling point of hydroxyethyl / propyl methacrylate is still relatively low (57-67°C), and the volatilization of small molecules cannot be completely prevented during the medium and high temperature aging process.

[0007] Therefore, the need to develop a polyurethane resin with low water sensitivity, high curing efficiency and low TVOC is a technical problem that technical personnel in this field currently need to solve. Summary of the invention

[0008] The present invention discloses a polyurethane polymer capable of light and heat dual curing and a composite material thereof, wherein the polyurethane polymer is prepared from raw materials comprising the following components:

[0009] (A) a polyisocyanate, wherein the polyisocyanate component comprises one or more organic polyisocyanates;

[0010] (B) an organic polyol component, wherein the organic polyol component comprises one or more organic polyols, and the organic polyol content is 10-80 wt.%, and the content is calculated as 100 wt.% based on the weight of the isocyanate component;

[0011] (C) an amine compound component containing an active unsaturated bond, wherein the amine compound component containing an active unsaturated bond comprises one or more compounds having an amino or imino group and an active unsaturated bond group and having a functionality greater than or equal to 2, and the content of the amine compound component containing an active unsaturated bond is 10-90 wt.%, and the content is calculated as 100 wt.% based on the weight of the isocyanate component;

[0012] (D) a reactive diluent component, the reactive diluent component comprising one or more low-viscosity liquid compounds containing reactive unsaturated bonds, wherein the reactive unsaturated bonds are reactive olefinic bonds or reactive acetylenic bonds with a number of ≥2, the viscosity of the reactive diluent component being 1-500 cP, the content of the reactive diluent component being 0-1000 wt.%, and the content being 100 wt.% based on the weight of the isocyanate component;

[0013] (E) a photocuring agent component 1, wherein the photocuring agent component 1 comprises one or more low-viscosity compounds that can rapidly excite active unsaturated bond groups under visible light conditions and complete active unsaturated bond free radical addition curing, the viscosity of the photocuring agent component 1 is 1-500 cP, and the content of the photocuring agent component 1 is 0-20 wt.%, and the content is calculated as 100 wt.% based on the weight of the isocyanate component.

[0014] (F) a thermal curing agent component 2, wherein the curing agent component 2 comprises one or more low-viscosity compounds that can rapidly excite active unsaturated bond groups under heating conditions and complete active unsaturated bond free radical addition curing, the curing agent component 1 has a viscosity of 1-500 cP, and a content of the curing agent component 1 of 0-20 wt.%, and its content is calculated as 100 wt.% based on the weight of the isocyanate component.

[0015] The polyisocyanate component (A) is selected from one of organic isocyanate monomers, isocyanate prepolymers, isocyanate-modified products or a mixture thereof. The functionality of the polyisocyanate component is 2-5, and the NCO content of the polyisocyanate component is 12-48%.

[0016] In some embodiments of the method according to the present invention, the polyisocyanate component (A) includes but is not limited to toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), naphthalene diisocyanate (NDI), p-phenylene diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CHDI), xylene diisocyanate (XDI), cyclohexane dimethylene diisocyanate (HXDI), trimethyl-1,6-hexamethylene diisocyanate (TMHDI), tetramethyl-m-xylene diisocyanate (TMHDI), isocyanate (TMXDI), norbornane diisocyanate (NBDI), dimethyl biphenyl diisocyanate (TODI), methyl cyclohexyl diisocyanate (HTDI), tetramethylene diisocyanate, 2-methylpentamethylene diisocyanate, dodecamethylene diisocyanate, 4,4'-diisocyanato-3,3'-dimethyldicyclohexylmethane, 4,4'-diisocyanato-2,2-dicyclohexylpropane, poly(hexamethylene diisocyanate), octamethylene diisocyanate, toluene-α,4-diisocyanate, 2,4,6-trimethyl-1,3-phenylene diisocyanate, 4-chloro-6-methyl-1,3-phenylene diisocyanate, poly[1,4- diisocyanate, 1,3-bis(1-isocyanato-1-methylethyl)benzene, 3,3'-dimethyl-4,4'-biphenyl diisocyanate, naphthalene-1,5-diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, 4,4'-, 2,4'- or 2,2'-diphenylmethane diisocyanate or mixtures of these isomers, 4,4'-, 2,4'- or 2,2'-diisocyanato-2,2-diphenylpropane, p-xylylene diisocyanate and at least one of the above isocyanate prepolymers and modified products, preferably toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), dicyclohexylmethane diisocyanate (HMDI), naphthalene diisocyanate (NDI), p-phenylene diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CHDI), xylylene diisocyanate (XDI), cyclohexane dimethylene diisocyanate (HXDI), At least one of trimethyl-1,6-hexamethylene diisocyanate (TMHDI), tetramethyl metaxylylene diisocyanate (TMXDI), norbornane diisocyanate (NBDI), dimethyl biphenyl diisocyanate (TODI), methyl cyclohexyl diisocyanate (HTDI) and the above isocyanate prepolymers and modified products, more preferably toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI) and the above isocyanate prepolymers and modified products.

[0017] The organic polyol component (B) is an organic polyol monomer, prepolymer, other organic polyol-modified product and a mixture thereof commonly used in the art. The hydroxyl value of the organic polyol is 10-600 mg KOH / g.

[0018] In some embodiments of the method according to the present invention, the organic polyol component (B) includes but is not limited to polyether polyols, polyester polyols, polyether carbonate polyols, polycarbonate polyols, bio-based polyols or any combination of the above organic polyols, preferably polyether polyols, polyester polyols, bio-based polyols, or mixtures thereof, more preferably polyether polyols, polyester polyols, or mixtures thereof.

[0019] The polyether polyol generally refers to an organic polyol series that can be prepared under the current existing process, which is mainly a class of compounds obtained by chemically reacting a polyol as an initiator and an alkylene oxide as a polymerization monomer under the action of a catalyst. The initiator includes but is not limited to water, ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, pentanediol, hexanediol, diethylene glycol, triethylene glycol, dipropylene glycol, diethylene glycol, neopentyl glycol, glycerol, trimethylolpropane, pentaerythritol, sorbitol, bisphenol A, bisphenol S, or a mixture thereof; the alkylene oxide includes but is not limited to ethylene oxide, propylene oxide, 1,2-butylene oxide, 2,3-butylene oxide, tetrahydrofuran, styrene oxide, or a mixture thereof; and the catalyst includes but is not limited to an alkaline hydroxide, an alkaline alcohol salt, antimony pentachloride, or a mixture thereof.

[0020] The polyester polyol generally refers to an organic dicarboxylic acid (anhydride or ester) and a polyol through condensation (or transesterification) or by polymerization of a lactone and a polyol, wherein the dicarboxylic acid includes but is not limited to phthalic acid, phthalic anhydride, phthalic acid ester, adipic acid, halogenated phthalic acid, or a mixture thereof, the polyol includes but is not limited to ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 1-pentanediol, hexanediol, diethylene glycol, triethylene glycol, dipropylene glycol, diethylene glycol, neopentyl glycol, glycerol, trimethylolpropane, pentaerythritol, sorbitol, bisphenol A, bisphenol S, or a mixture thereof, and the lactone includes but is not limited to butyrolactone, lauryl lactone, tetradecalactone, or a mixture thereof.

[0021] The polycarbonate polyol can be prepared by using a cyanide containing a bimetallic element as a catalyst to react a carbon dioxide core epoxy compound with a starting material containing an active hydrogen atom.

[0022] The bio-based polyol is an oligomer polyol obtained from animals and plants as raw materials, which is a renewable resource. The animal and plant raw materials include but are not limited to vegetable oils, animal fats, wood, rosin, starch, or mixtures thereof. The vegetable oil is a compound prepared from unsaturated fatty acids and glycerol or an oil extracted from plant fruits, seeds, germs or mixtures thereof, including but not limited to castor oil, rapeseed oil, palm oil, soybean oil, peanut oil, etc.

[0023] The active unsaturated bond-containing amine compound (C) is a compound, polymer or mixture thereof containing an amino group (-NH2, -NH-) and an active unsaturated bond group in the molecular structure and having an average functionality greater than or equal to 2:

[0024] In some embodiments of the method according to the present invention, the amine compound component (C) containing an active unsaturated bond includes but is not limited to one or more of acrylamide, methacrylamide, N-tert-butylacrylamide, N-methyl-5-hexen-1-amine, 1-amino-5-hexene, N-propyl-6-hexenamine, N-allyl-5-hexen-1-amine, di(hex-5-enyl)amine, 1-methylaminoundec-10-ene, vinylamine and homopolymers thereof.

[0025] The reactive diluent component (D) refers to a low-viscosity liquid compound having at least one or more reactive unsaturated bonds in its molecular structure, wherein the reactive olefinic bonds are ≥2 or the reactive acetylenic bonds are contained;

[0026] In some embodiments of the method according to the present invention, the active diluent component includes but is not limited to difunctional (meth)acrylates, multifunctional (meth)acrylates, di / multifunctional vinyl (ethers), and mono / multifunctional acetylene diluents. The difunctional (meth)acrylate diluents include but are not limited to 1,6-hexanediol diacrylate (HDDA), 1,6-hexanediol di(meth)acrylate, and di(meth)acrylate. One or more of acrylate (HDDA), dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), diethylene glycol diacrylate (DEGDA), diethylene glycol dimethacrylate (DEGDMA), triethylene glycol di(meth)acrylate (TEGDMA), ethoxylated bisphenol A (meth)acrylate, polyethylene glycol di(meth)acrylate, neopentyl glycol diethoxy / propoxy diacrylate, or a combination of the above compounds; multifunctional (meth)acrylate diluents include but are not limited to trimethylolpropane tri(meth)acrylate (TMPTA), pentaerythritol triacrylate (PETA), tris(2-hydroxyethyl)isocyanate triacrylate (THEICTA), pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate (DPEPA), dipentaerythritol hexaacrylate (DPHA), ditrimethylolpropane tetraacrylate (DTEMPTT A), ethoxylated multifunctional acrylates, propoxylated multifunctional acrylates, vinyl acetate (VA), vinyl ethoxyethyl acrylate (VEEA), 2-allyloxyethoxymethyl acrylate, or a combination of the above compounds; di / multifunctional vinyl (ether) diluents include but are not limited to triethylene glycol divinyl ether (DVE-3), 1,4-cyclohexyl dimethanol divinyl ether (CHVE), vinyl ether, ethylene glycol divinyl ether, diethylene glycol vinyl ether, triethylene glycol vinyl ether, tetra(ethylene glycol) divinyl ether, pentaerythritol trivinyl ether, 1,3-bis(vinyloxy)-2,2-bis[(vinyloxy)methyl]propane, or a combination of the above compounds; mono / multifunctional ethynyl diluents include but are not limited to one or more of propynyl alcohol ethoxy ether, 6-heptynol, 3-cyclohexylpropyne, 7-octynol, propynyl dimerized glycol, or a combination of the above compounds.

[0027] The curing agent component 1 refers to one or more low-viscosity compounds or their mixtures that can quickly excite active unsaturated bond groups under visible light conditions to complete active unsaturated bond free radical addition curing.

[0028] In some embodiments of the method according to the present invention, the curing agent component includes but is not limited to curing agents commonly found in the polymer field that can be catalyzed under visible light conditions, such as 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexyl benzophenone, 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone, benzoin dimethyl ether, one or more of 2,4,6-trimethylbenzoyldiphenylphosphine oxide, or a combination of the above compounds.

[0029] The curing agent component 2 refers to one or more low-viscosity compounds or a mixture thereof that can quickly activate active unsaturated bond groups under heating conditions to complete active unsaturated bond free radical addition curing.

[0030] In some embodiments of the method according to the present invention, the second curing agent component includes but is not limited to the common curing materials in the polymer field that can initiate active unsaturated bond free radical addition polymerization under heating conditions, such as benzoyl peroxide, benzophenone, acetophenone, chlorinated acetophenone, dialkoxyacetophenone, dialkylhydroxyacetophenone, dialkylhydroxyacetophenone ester, benzoin, benzoin acetate, benzoin alkyl ether, dimethoxybenzoin, dibenzyl ketone, benzoyl cyclohexanol and other aromatic ketones, acyl oxime esters, acyl phosphine oxides, acyl phosphoryl (phos) phosphonates, ketone sulfides, dibenzoyl disulfide, diphenyl dithiocarbonate and diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, or one or more of the above compounds, or a combination of the above compounds.

[0031] In an embodiment of the present invention, the steps for preparing a polyurethane polymer capable of being cured by light and heat are as follows:

[0032] (I) generating a polyurethane prepolymer having terminal isocyanate groups by reacting an isocyanate component (A) with an organic polyol component (B);

[0033] (II) adding an amine compound component (C) containing an active unsaturated bond to the above-mentioned polyurethane prepolymer containing an isocyanate group end-capping, and an amino group or an imino group (-NH2, -NH-) reacts with the isocyanate group to form a urea group or a carbamate group structure, thereby end-capping the isocyanate group to obtain a polyurethane resin containing an active unsaturated bond end-capping;

[0034] (III) Adding appropriate amounts of active diluent (D), curing agent 1 (E) and curing agent 2 (F) to the above-mentioned polyurethane resin containing active unsaturated bonds to adjust the viscosity of the resin, thereby obtaining end-capped polyurethane resins with different viscosities and curing ability.

[0035] In a specific embodiment of the present invention, in the step (I) in which the isocyanate component (A) reacts with the organic polyol component (B) to generate a polyurethane prepolymer having an isocyanate terminal, the reaction temperature is 25-100°C. If the reaction temperature is set below 25°C, the polymerization reaction is usually slow. If the reaction temperature is higher than 100°C, a violent polymerization phenomenon may occur, resulting in cross-linking and curing of the prepolymer, which cannot be diluted later.

[0036] In a specific embodiment of the present invention, the step (I) of reacting the isocyanate component (A) with the organic polyol component (B) to form the polyurethane prepolymer having terminal isocyanate groups is carried out for a reaction time of 2-10 hours.

[0037] In a specific embodiment of the present invention, the reaction of the isocyanate component (A) and the organic polyol component (B) in step (I) to generate the polyurethane prepolymer with terminal isocyanate groups can be catalyzed by using some known catalysts, and the catalyst can be a catalyst commonly used in the art that can catalyze the reaction of isocyanate groups (-N=C=O) and hydroxyl groups (-OH). Suitable catalysts for the reaction are preferably, but not limited to, organic metal catalysts, amine catalysts or mixtures thereof. The amine catalyst is preferably, but not limited to, triethylamine, tributylamine, triethylenediamine, N-ethylmorpholine, N,N,N',N'-tetramethyl-ethylenediamine, pentamethyldiethylene-triamine, N,N-methylaniline, N,N-dimethylaniline or mixtures thereof. The organometallic catalyst is preferably, but not limited to, an organotin compound, such as tin acetate, tin octoate, tin ethylhexanoate, tin laurate, dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin maleate, dioctyltin diacetate, or a mixture thereof. The amount of the catalyst used is 0.001-5 wt.%, and the amount used is calculated based on 100 wt.% of the total weight of the isocyanate component (A).

[0038] In a specific embodiment of the present invention, in step (II), an amine compound component (C) containing an active unsaturated bond is added to a polyurethane prepolymer having an isocyanate group at the end. The amino group reacts with the isocyanate group at a relatively fast rate, usually without the need for a catalyst, thereby obtaining a polyurethane polymer having an active unsaturated bond at the end. The reaction is carried out at 25-160°C. If the temperature is set below 25°C, the polymerization reaction is usually slow. If the temperature is higher than 160°C, the reaction rate will be too fast, resulting in a large temperature rise, and the temperature of the reaction system cannot be effectively controlled, which is dangerous.

[0039] In a specific embodiment of the present invention, in step (II), an amine compound component (C) containing an active unsaturated bond is added to a polyurethane prepolymer having an isocyanate group at the end, and the isocyanate group reacts with the amino group (-NH2, -NH-) to form a urea group or an allophanate group structure, thereby capping the isocyanate, and obtaining a polyurethane polymer having an active unsaturated bond at the end, and the reaction time is 2-10 hours.

[0040] In an embodiment of the present invention, in step (III), a proper amount of a diluent component (D) is added to the polyurethane polymer having terminal active unsaturated bonds to adjust the polymer viscosity and obtain a polyurethane polymer of desired viscosity. The temperature during dilution of the polyurethane polymer is 25-80°C. If the temperature during dilution of the polyurethane polymer is set below 25°C, the viscosity of the polyurethane polymer containing residual active unsaturated bonds is relatively high, which is not conducive to the dilution process. If the temperature is higher than 80°C, the active unsaturated bonds contained in the polymer may react with the diluent to undergo an active unsaturated bond addition reaction, resulting in the solidification of the polymer.

[0041] In an embodiment of the present invention, in step (III), a proper amount of diluent component (D) is added to the polyurethane polymer having terminal active unsaturated bonds to adjust the polymer viscosity and obtain a polyurethane polymer of desired viscosity, and the dilution time is 0.5-5h.

[0042] In an embodiment of the present invention, in step (III), an appropriate amount of curing agent component 1 (E) is added to the polyurethane polymer having terminal active unsaturated bonds, so that the polyurethane polymer has curing ability under visible light conditions. The curing agent component 1 should be added under light-proof conditions, especially under visible light such as ultraviolet light. If irradiated under ultraviolet light, the curing agent will cause the active unsaturated bonds of the polyurethane polymer having terminal active unsaturated bonds and the active diluent to break, causing a free radical polymerization reaction of the active unsaturated bonds, resulting in the curing of the polymer.

[0043] In an embodiment of the present invention, in step (III), a proper amount of curing agent component 1 (E) is added to the polyurethane polymer having terminal active unsaturated bonds so that the polyurethane polymer has curing ability under visible light conditions, and the addition time is 0.1-0.5h.

[0044] In an embodiment of the present invention, in step (III), an appropriate amount of curing agent component 2 (F) is added to the polyurethane polymer having terminal active unsaturated bonds so that the polyurethane polymer has curing ability under heating conditions, and the temperature when the curing agent component 2 is added is 20-35° C.; if the temperature when diluting the polyurethane polymer is set below 20° C., the viscosity of the polyurethane polymer containing residual active unsaturated bonds is relatively large, which is not conducive to the curing agent dispersion process. If the temperature is higher than 35° C., the active unsaturated bonds contained in the polymer may react with the diluent to undergo an active unsaturated bond addition reaction, resulting in the curing of the polymer.

[0045] In an embodiment of the present invention, in step (III), a proper amount of curing agent component 2 (F) is added to the polyurethane polymer having terminal active unsaturated bonds so that the polyurethane polymer has curing ability under heating conditions, and the addition time is 0.1-0.5h.

[0046] In the embodiments of the present invention, the polyurethane polymer with terminal active unsaturated bonds can be stored at 0-60°C and 0-50RH% for 60 days without significant changes in its physical and chemical properties. The composite material prepared based on the polyurethane polymer still has good performance, indicating that the resin has extremely low water sensitivity, a long shelf life and a storage environment with a wide tolerance.

[0047] The present invention also provides a composite material, which is prepared by the following steps:

[0048] (I) blending the above-mentioned polyurethane polymer and reinforcing material, and stirring them uniformly to obtain a polyurethane composite material mixture or paste, thereby preparing the polyurethane composite material;

[0049] (II) curing the polyurethane composite material, wherein the composite material is cured to complete the preparation by causing the active unsaturated bonds in the polyurethane resin to undergo addition polymerization or other reactions that can generate a cross-linked network structure under the catalysis of the photocuring and thermal curing of the curing agent components one and two.

[0050] The reinforcing material refers to the reinforcing material commonly used in the field of composite materials, and there is no clear requirement for the shape and size of the reinforcing material during use. It can be a continuous fiber reinforcement material, a chopped fiber reinforcement material, a fiber fabric, etc.

[0051] In an embodiment of the present invention, the reinforcing material includes but is not limited to one or more of glass fiber (glass fiber), carbon fiber (carbon fiber), polyester fiber, natural fiber, aromatic polyamide fiber, nylon fiber, basalt fiber, boron fiber, silicon carbide fiber, asbestos fiber, whisker, and metal fiber.

[0052] In the embodiments of the present invention, the polyurethane polymer may also contain some functional additives or additives, including but not limited to chain extenders, small molecule raw materials, internal mold release agents, flame retardants, fillers, pigments, antioxidants, foaming agent stabilizers, light stabilizers, auxiliary antioxidants, hydrolysis stabilizers, bactericides and mildew inhibitors, defoamers, rheological agents, leveling agents, wetting agents, reactive diluents, coupling agents, color pastes, catalysts, water removers, molecular sieves, or mixtures of the above additives and additives. The above components can be stored independently of the polyurethane polymer system, and can be added to the polyurethane polymer after it is prepared, or can be added to the polyurethane polymer during the preparation process.

[0053] In some embodiments of the method according to the present invention, the polyurethane composite material can be prepared by hand lay-up molding process, bag pressing method (pressure bag method) molding, vacuum bag pressing molding, autoclave molding technology, thermal expansion molding technology, sandwich structure molding technology, molding material production process, compression molding process, rolled tube molding technology, thermoplastic sheet molding material manufacturing technology and cold mold stamping molding process.

[0054] The beneficial effects of the present invention are:

[0055] To solve the problems of high water sensitivity and harsh storage conditions of traditional polyurethane resins, photothermal dual curing is used to solve its application problems in the field of thick products. The multifunctional diluent component containing unsaturated bonds is creatively used, which not only plays the role of diluent but also can be used as a chemical cross-linking agent or chain extender. The polymer viscosity can be adjusted arbitrarily and act as a chemical cross-linking agent or chain extender during the curing process, showing the advantages of efficient aging and ensuring excellent mechanical properties, while reducing TVOC. DETAILED DESCRIPTION

[0056] The present invention is further described in detail below through specific embodiments, but this should not be construed as limiting the scope of the present invention to the following examples. Various substitutions or changes made according to common technical knowledge and customary means in the art without departing from the above-mentioned method concept of the present invention should be included in the scope of the present invention. In this application, parts and % are usually measured by mass unless otherwise specified.

[0057] The raw materials used in the examples are as follows:

[0058] Isocyanate component (A): WANNATE PM200, WANNATE MDI-50, WANNATE MDI-100, WANNATE8311, Wanhua Chemical;

[0059] Organic polyol component (B): polyether polyol 1 (R2304, Wanhua Chemical), polyester polyol 2 (Reynol PS-260, Ruinuo Chemical), polycarbonate polyol 3 (CD205HL, Daicel Corporation of Japan), bio-based polyol 4 (JTM-400, Jintian Chemical)

[0060] Catalyst components: bis(dimethylaminoethyl) ether, tributylamine, dibutyltin oxide, dibutyltin dichloride, purchased from Aladdin;

[0061] Amine compound component containing active unsaturated bonds (C): methacrylamide, N-tert-butylacrylamide, 1-amino-5-hexene, N-allyl-5-hexene-1-amine; purchased from Aladdin;

[0062] Diluent component (D): 1,6-hexanediol di(meth)acrylate (HDDMA), dipropylene glycol diacrylate (DPGDA), diethylene glycol diacrylate (DEGDA), dipentaerythritol pentaacrylate (DPEPA); purchased from Aladdin;

[0063] Photocuring agent (E): 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexyl benzophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide; purchased from Aladdin;

[0064] Thermal curing agent (F): benzoyl peroxide, dibenzoyl disulfide, diphenyl dithiocarbonate; purchased from Aladdin;

[0065] Reinforcement material components: chopped glass fiber; purchased from Shandong Taicheng Fiber Co., Ltd.

[0066] The amounts of the components used in the examples and comparative examples are listed in Tables 1 to 3.

[0067] Table 1 Example formulation

[0068]

[0069]

[0070] Note: All weight parts in Table 1 are calculated based on 100 wt.% of isocyanate.

[0071] Table 2 Comparative Example Formula

[0072] Raw material name Comparative Example 1 HPMA 10 Polyether polyol 1 90 Benzoyl peroxide 0.25 Tert-Butyl Perbenzoate 0.25 Dicumyl peroxide 0.25 Demsodur 1511L 72.9

[0073] Table 3 Comparative Example Formula

[0074]

[0075]

[0076] Embodiment 1:

[0077] Step I: Synthesis of end-capped polyurethane resin

[0078] (1) Add the materials in Table 1. Add WANNATE PM-200 (100 g), polyether polyol 1 (45 g), and bis(dimethylaminoethyl) ether (0.1 g) into a clean 2000 mL four-necked round-bottom flask at 25° C., start mechanical stirring at a speed of 150 rpm, then place the round-bottom flask in an oil bath at 25° C. for constant temperature reaction. After 10 hours, the NCO content in the reaction system is 17.5 wt.% (theoretical NCO % (wt.%), indicating that the prepolymer reaction is complete; then methacrylamide (44g) is added to the above prepolymer, and then the reaction system is heated to 140°C for reaction for 2.5h. After a total reaction time of 12h, the NCO content in the reaction system is 0.1wt.%, and the end-capping reaction is completed to obtain a polyurethane resin with terminal active unsaturated bonds; active diluent 1,6-hexanediol di(meth)acrylate (130g) is added to the above polyurethane resin with terminal active unsaturated bonds, and stirred and diluted at 25°C. After 5h, the reaction system is a uniform transparent viscous colloid, indicating that the dilution process is complete, and then it is allowed to stand to room temperature, and curing agents 2-hydroxy-2-methyl-1-phenylacetone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and benzoyl peroxide are added thereto, and stirred for 20min to ensure that the system is fully mixed and uniform, to obtain a blocked polyurethane resin 1, which is collected into a bottle.

[0079] Step II: Preparation of composite materials of blocked polyurethane resin

[0080] Take 200g of end-capped polyurethane resin 1 and 200g of chopped glass fiber and put them into a blender. Stir them into a paste in a dark environment until the glass fiber is completely soaked. Pour the mixture into a 20×20×1cm 3 The composite material 1 was obtained by placing it in a transparent PC board mold and finally irradiating it with ultraviolet light and heating it to 50°C and curing it for 60 minutes.

[0081] Embodiment 2:

[0082] Step I: Synthesis of end-capped polyurethane resin

[0083] (1) The materials in Table 1 were added into a clean 2000 mL four-necked round-bottom flask at 25° C. WANNATE MDI-50 (100 g), polyether polyol 1 (65 g), polyether polyol 2 (15 g), and tributylamine (0.1 g). Mechanical stirring was started at a speed of 120 rpm. The round-bottom flask was then placed in an oil bath at 60° C. for constant temperature reaction. After 5 hours, the NCO content in the reaction system was 16.5 wt.% (theoretical NCO The content is 16wt.%), indicating that the prepolymer reaction is completed; N-tert-butyl acrylamide (40g) is then added to the above prepolymer, and then the reaction system is heated to 120°C for reaction for 3h. After a total reaction time of 8h, the NCO content in the reaction system is 0.1wt.%, and the end-capping reaction is completed to obtain a polyurethane resin with terminal active unsaturated bonds; a reactive diluent dipropylene glycol diacrylate (150g) is added to the above polyurethane resin with terminal active unsaturated bonds, and stirred and diluted at 70°C. After 2h, the reaction system is a uniform transparent viscous colloid, indicating that the dilution process is completed, and then allowed to stand to room temperature, and curing agents 1-hydroxycyclohexyl benzophenone, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, dibenzoyl disulfide and benzoyl peroxide are added thereto, and stirred for 20min to ensure that the system is fully mixed and uniform, to obtain a blocked polyurethane resin 1, which is collected into a bottle.

[0084] Step II: Preparation of composite materials of blocked polyurethane resin

[0085] Take 200g of end-capped polyurethane resin 1 and 200g of chopped glass fiber and put them into a blender. Stir them into a paste in a dark environment until the glass fiber is completely soaked. Pour the mixture into a 20×20×1cm 3 The composite material 2 was obtained by placing it in a transparent PC board mold and finally irradiating it with ultraviolet light and heating it to 150°C and curing it for 3 minutes.

[0086] Embodiment 3:

[0087] Step I: Synthesis of end-capped polyurethane resin

[0088] (1) Add the materials in Table 1 to a clean 2000 mL four-necked round-bottom flask at 25° C., add WANNATE MDI-100 (100 g), polyether polyol 3 (65 g), and dibutyltin oxide (0.3 g), start mechanical stirring at a speed of 100 rpm, then place the round-bottom flask in an oil bath at 100° C. for constant temperature reaction. After 1 hour, the NCO content in the reaction system is 16.1 wt.% (theoretical NCO content is 15.5 wt.%), indicating that the prepolymer reaction is completed; then 1-amino-5-hexene (46g) is added to the above prepolymer, and then the reaction system is heated to 160°C for reaction for 0.5h. After a total reaction time of 2h, the NCO content in the reaction system is 0.1wt.%, and the end-capping reaction is completed to obtain a polyurethane resin with terminal active unsaturated bonds; active diluent diethylene glycol diacrylate (200g) is added to the above polyurethane resin with terminal active unsaturated bonds, and stirred and diluted at 25°C. After 5h, the reaction system is a uniform transparent viscous colloid, indicating that the dilution process is completed, and then allowed to stand to room temperature, and curing agents 2-hydroxy-2-methyl-1-phenylacetone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and diphenyl dithiocarbonate benzoyl peroxide are added thereto, and stirred for 20min to ensure that the system is fully mixed and uniform, to obtain a blocked polyurethane resin 1, which is collected into a bottle.

[0089] Step II: Preparation of composite materials of blocked polyurethane resin

[0090] Take 200g of end-capped polyurethane resin 1 and 200g of chopped glass fiber and put them into a blender. Stir them into a paste in a dark environment until the glass fiber is completely soaked. Pour the mixture into a 20×20×1cm 3 The composite material 3 was obtained by placing it in a transparent PC board mold and finally irradiating it with ultraviolet light and heating it to 80°C and curing it for 10 minutes.

[0091] Embodiment 4:

[0092] Step I: Synthesis of end-capped polyurethane resin

[0093] (1) Add the materials in Table 1 to a clean 2000 mL four-necked round-bottom flask at 25° C.: WANNATE PM-200 (55 g), WANNATE MDI-50 (20 g), WANNATE MDI-100 (15 g), WANNATE 8311 (10 g), polyether polyol 3 (40 g), polyether polyol 4 (25 g), dibutyltin dichloride (0.2 g), start mechanical stirring at a speed of 150 rpm, then place the round-bottom flask in an oil bath at 65° C. for constant temperature reaction. After 3 hours, the NCO content in the reaction system is 17.5 wt.% (theoretical NCO content is 16.9wt.%), indicating that the prepolymer reaction is completed; N-allyl-5-hexene-1-amine (44g) is then added to the above prepolymer, and then the reaction system is heated to 140°C for reaction for 2.5h. After a total reaction time of 6h, the NCO content in the reaction system is 0.1wt.%, and the end-capping reaction is completed to obtain a polyurethane resin with terminal active unsaturated bonds; active diluent dipentaerythritol pentaacrylate (290g) is added to the above polyurethane resin with terminal active unsaturated bonds, and stirred and diluted at 50°C. After 5h, the reaction system is a uniform transparent viscous colloid, indicating that the dilution process is completed, and then it is allowed to stand to room temperature, and a curing agent 2-hydroxy-2- Methyl-1-phenylacetone, 1-hydroxycyclohexyl benzophenone, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzoyl peroxide and diphenyl dithiocarbonate were stirred for 20 minutes to ensure that the system was fully mixed to obtain a blocked polyurethane resin 1, which was collected into a bottle.

[0094] Step II: Preparation of composite materials of blocked polyurethane resin

[0095] Take 200g of end-capped polyurethane resin 1 and 200g of chopped glass fiber and put them into a blender. Stir them into a paste in a dark environment until the glass fiber is completely soaked. Pour the mixture into a 20×20×1cm 3 The composite material 4 was obtained by placing it in a transparent PC board mold and finally irradiating it with ultraviolet light and heating it to 80°C and curing it for 3 minutes.

[0096] Comparative Example 1-2

[0097] The two-component polyurethane resin was prepared according to the proportions in Table 2 and Table 3, and then the polyurethane composite material was prepared according to Step II of Example 1.

[0098] The test methods or standards used in the embodiments and comparative examples are as follows:

[0099] Flexural modulus test standard: DIN ISO 527;

[0100] The bending strength test standard is: DIN ISO 527;

[0101] Impact strength test standard: GB / T 1043-2008;

[0102] The tensile strength test standard is: DIN ISO 527;

[0103] The elongation at break test standard is: DIN ISO 527;

[0104] Resin TVOC characterization: refer to QJ / XP 16BZ.002-2020, Tedlar Bag method. The analytical instruments are thermal desorption-gas chromatography-mass spectrometry (TDS-GC / MS) and high performance liquid chromatography (HPLC);

[0105] Resin curing degree test: DSC is used to test the total amount of heat released when the isocyanate component and the isocyanate reactive component are mixed until they are fully cured (recorded as Q total ); Take the cured resin sample without any treatment after demoulding and perform DSC test until it is fully matured, and record the heat release as Q sample ; The test conditions selected during all tests remain the same, and the degree of ripening is calculated according to the following formula:

[0106]

[0107] The composite material prepared in the above embodiment was subjected to performance tests, and the test results are listed in Table 4:

[0108] Table 4

[0109]

[0110] Take 100g of each of the resin components in Examples 1-4 and Comparative Example 1 and place them in a 5×5×0.1cm 3 In the mold, it was cured for 1 min at 100°C and 254nm UV intensity. The degree of curing is shown in Table 5.

[0111] Table 5

[0112] Performance Testing Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Maturity / % 96 93 89 92 84

[0113] It can be seen from the table that under the same curing conditions, the resin system described in the present invention exhibits a more efficient curing rate.

[0114] Take 100g of each of the resin components in Examples 1-4 and Comparative Example 1 and place them in a 5×5×0.1cm 3 In the mold, comparative example 1 was aged for 1 min at 100°C and under 254nm UV intensity, and examples 1-4 were aged for 1 min at 75°C and under 254nm UV intensity. The degree of aging is shown in Table 6

[0115] Table 6

[0116] Performance Testing Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Maturity / % 87 82 80 84 82

[0117] It can be seen from the table that the resin system described in the present invention exhibits the characteristic of rapid curing at low temperature.

Claims

1. A polyurethane polymer capable of being cured both photo-thermally and photo-cured, wherein the polyurethane polymer is prepared from raw materials comprising the following components: (A) a polyisocyanate, wherein the polyisocyanate component comprises one or more organic polyisocyanates; (B) an organic polyol component, wherein the organic polyol component comprises one or more organic polyols, and the organic polyol content is 10-80 wt.%, and the content is calculated as 100 wt.% based on the weight of the isocyanate component; (C) an amine compound component containing an active unsaturated bond, wherein the amine compound (C) containing an active unsaturated bond is one or more of acrylamide, methacrylamide, N-tert-butylacrylamide, N-methyl-5-hexene-1-amine, 1-amino-5-hexene, N-propyl-6-hexenylamine, N-allyl-5-hexen-1-amine, di(hex-5-enyl)amine, 1-methylaminoundec-10-ene, and vinylamine; the content of the amine compound component containing an active unsaturated bond is 10-90wt.%, and the content is calculated as 100wt.% based on the weight of the isocyanate component; (D) a reactive diluent component, the reactive diluent component comprising one or more low-viscosity liquid compounds containing reactive unsaturated bonds, wherein the reactive unsaturated bonds are reactive olefinic bonds or reactive acetylenic bonds with a number of ≥2, the viscosity of the reactive diluent component being 1-500 cP, the content of the reactive diluent component being 130-1000 wt.%, and the content being 100 wt.% based on the weight of the isocyanate component; (E) a photocuring agent component 1, wherein the photocuring agent component 1 is selected from one or more of 2-hydroxy-2-methyl-1-phenylpropanone, 1-hydroxycyclohexyl benzophenone, 2-methyl-1-(4-methylthiophenyl)-2-morpholinyl-1-propanone, benzoin dimethyl ether, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, or a combination of the above compounds, The content of the first curing agent component is 0.1-20 wt.%, and its content is based on 100 wt.% of the weight of the isocyanate component; (F) a second thermal curing agent component, wherein the second curing agent component is selected from one or more of benzoyl peroxide, benzophenone, acetophenone, chlorinated acetophenone, dialkoxyacetophenone, dialkylhydroxyacetophenone, dialkylhydroxyacetophenone ester, benzoin, benzoin acetate, benzoin alkyl ether, dimethoxybenzoin, dibenzyl ketone, benzoyl cyclohexanol and other aromatic ketones, acyl phosphine oxide, dibenzoyl disulfide, diphenyl dithiocarbonate and diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide, or a combination of the above compounds, and the content of the second curing agent component is 0.1-20wt.%, and its content is based on 100wt.% of the weight of the isocyanate component.

2. The light-heat-dual-curable polyurethane polymer according to claim 1, characterized in that: The polyisocyanate component (A) is selected from one of organic isocyanate monomers, isocyanate prepolymers, isocyanate-modified products or a mixture thereof. The functionality of the polyisocyanate component is 2-5, and the NCO content of the polyisocyanate component is 12-48%.

3. The light-heat-dual-curable polyurethane polymer according to claim 1, characterized in that: The hydroxyl value of the organic polyol is 10-600 mg KOH / g; and / or the organic polyol component (B) comprises polyether polyol, polyester polyol, polyether carbonate polyol, polycarbonate polyol, bio-based polyol or any combination of the above organic polyols.

4. The light-heat-curable polyurethane polymer according to any one of claims 1 to 3, characterized in that: The reactive diluent component (D) includes difunctional (meth)acrylates, multifunctional (meth)acrylates, di / multifunctional vinyl ethers, and mono / multifunctional acetylene diluents; And / or, wherein the difunctional (meth)acrylate diluent includes one or more of 1,6-hexanediol diacrylate (HDDA), 1,6-hexanediol dimethacrylate, dipropylene glycol diacrylate (DPGDA), tripropylene glycol diacrylate (TPGDA), diethylene glycol diacrylate (DEGDA), diethylene glycol dimethacrylate (DEGDMA), triethylene glycol di(meth)acrylate (TEGDMA), polyethylene glycol di(meth)acrylate, neopentyl glycol diethoxy / propoxy diacrylate, or a combination of the above compounds; the multifunctional (meth)acrylate diluent includes trimethylolpropane tri(meth)acrylate (TMPTA), pentaerythritol triacrylate (PETA), tris(2-hydroxyethyl)isocyanate triacrylate (THEICTA), pentaerythritol tetraacrylate, dipentaerythritol pentaacrylate (D The invention relates to a novel polyvinyl alcohol diluent comprising one or more of diethylene glycol divinyl ether (DVE-3), 1,4-cyclohexyl dimethanol divinyl ether (CHVE), ethylene glycol divinyl ether, diethylene glycol vinyl ether, triethylene glycol vinyl ether, tetra(ethylene glycol) divinyl ether, pentaerythritol trivinyl ether, 1,3-bis(vinyloxy)-2,2-bis[(vinyloxy)methyl]propane, or a combination of the above compounds; a mono / multifunctional ethynyl diluent comprises one or more of propynyl alcohol ethoxy ether, 6-heptynol, 3-cyclohexylpropyne, 7-octynol, propynyl dimerized glycol, or a combination of the above compounds.

5. The method for preparing a light-thermal dual-curable polyurethane polymer according to any one of claims 1 to 4, comprising the following steps: (I) generating a polyurethane prepolymer having terminal isocyanate groups by reacting an isocyanate component (A) with an organic polyol component (B); (II) adding an amine compound component (C) containing an active unsaturated bond to the above polyurethane prepolymer containing an isocyanate group, and reacting the amino group or the imino group (-NH2, -NH-) with the isocyanate group to obtain a polyurethane resin containing an active unsaturated bond; (III) Add appropriate amounts of active diluent (D), curing agent 1 (E) and curing agent 2 (F) to the above-mentioned polyurethane resin containing active unsaturated bonds to obtain a blocked polyurethane resin.

6. A composite material, characterized in that: The composite material is prepared by the following steps: (I) blending the photo-thermal dual-curable polyurethane polymer according to any one of claims 1 to 4 or the photo-thermal dual-curable polyurethane polymer prepared by the preparation method according to claim 5 and a reinforcing material, stirring them uniformly to obtain a polyurethane composite material mixture or a paste to obtain a polyurethane composite material; (II) curing the polyurethane composite material, wherein the composite material is cured by causing the active unsaturated bonds in the polyurethane resin to undergo addition polymerization or other reactions that can generate a cross-linked network structure under the catalysis of light curing and heat curing.

7. The composite material according to claim 6, characterized in that The reinforcing material includes one or more of glass fiber (glass fiber), carbon fiber (carbon fiber), polyester fiber, aromatic polyamide fiber, nylon fiber, basalt fiber, boron fiber, silicon carbide fiber, asbestos fiber, whisker, and metal fiber.

8. The composite material according to claim 6, characterized in that The reinforcement material comprises natural fibers.

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