Cardanol-based polyhydric alcohol, polyurethane foam material and preparation method of cardanol-based polyhydric alcohol and polyurethane foam material

Abstract

The invention discloses cardanol-based polyol, a polyurethane foam material and a preparation method of the cardanol-based polyol and the polyurethane foam material. The cardanol-based polyol is prepared by taking cardanol monomers and a disulfhydryl compound as reaction raw materials, and carrying out hot click reaction on sulfhydryl-ene under a heating condition or carrying out light click reaction under illumination under the initiation of a photoinitiator. The cardanol-based polyurethane foam material is prepared from the following raw materials in parts by weight: 50 to 100 parts of cardanol-based polyol, 1 to 3 parts of water, 10 to 50 parts of dihydric alcohol, 0.1 to 1 part of a catalyst, 1 to 5 parts of a chain extension cross-linking agent, 1 to 3 parts of silicone oil and 30 to 80 parts of isocyanate. The synthesis method of the cardanol-based polyol has the advantages of simplicity, high efficiency and the like, and the cardanol-based polyurethane foam material has good performance and is expected to replace the traditional petroleum-based polyol polyurethane foam, so that the dependence of the polyurethane foam industry on petrochemical resources is reduced, and the agricultural and sideline product cardanol is fully utilized.

Description

Technical Field

[0001] The present invention belongs to the technical field of bio-based polyols and polyurethane foam materials, and particularly relates to a cardanol-based polyol and a polyurethane foam material and a preparation method thereof. Background Art

[0002] Polyurethane is a macromolecular compound with many repeating urethane groups on the main chain, generally obtained by polymerizing diol or polyol compounds with polyisocyanates. Polyurethane foam is one of the main types of polyurethane products, which can be divided into rigid foam, flexible foam, semi-rigid foam, etc. The main raw materials of traditional polyurethane foam, polyols and isocyanates, come from the petrochemical industry. At present, with the increasing shortage of petroleum resources and the more prominent ecological environment problems, replacing petrochemical raw materials with renewable resources meets the requirements of society for green and sustainable development, and thus is gradually attracting people's attention.

[0003] Cardanol is the main component of cashew nut shell liquid, which has a unique molecular structure with an unsaturated pentadecyl long-chain side group at the meta position of phenol. It can undergo various reactions and is convenient for modification. At present, it has been used in many fields such as phenolic resin, epoxy resin, and photocurable resin. At present, the synthesis of cardanol-based polyols and their polyurethane products at home and abroad mainly focuses on introducing functional groups such as hydroxyl groups by reacting with the unsaturated double bonds on the long side chain of cardanol, or ring-opening the epoxy group of cardanol glycidyl ether to generate hydroxyl groups. The thiol-ene click reaction has the advantages of wide raw material sources, large selectivity, high reaction efficiency, mild and controllable conditions, etc. Through the thiol-ene click reaction, the simple and efficient synthesis of polyols can be realized, and it is expected to promote the substitution of bio-based polyols for traditional petrochemical products, thus promoting the green development of the polyurethane industry. Summary of the Invention

[0004] Aiming at the deficiencies of the existing technology, the purpose of the present invention is to provide a cardanol-based polyol and a polyurethane foam material and a preparation method thereof.

[0005] The purpose of the present invention is achieved by the following technical solutions:

[0006] A cardanol-based polyol, wherein the cardanol-based polyol is synthesized by using cardanol monomers and bis-mercapto compounds as reaction raw materials through a thermal click reaction of thiol-ene under heating conditions or a photo click reaction initiated by a photoinitiator under light irradiation.

[0007] Preferably, the cardanol monomers are one or more of cardanol and cardanol derivatives containing long side chains and multiple unsaturated double bonds;

[0008] More preferably, the cardanol derivative containing multiple unsaturated double bonds is cardanol ethylene glycol ether.

[0009] Preferably, the dithiol compound is one or more of ethylene glycol bis(mercaptoacetate), 1,4-benzenedimethanethiol, 1,4-butanediol bis(mercaptoacetate), 2,5-dimercapto-1,3,4-thiadiazole, ethylene glycol bis(3-mercaptopropionate), and 2,3-dithio(2-mercapto)-1-propanethiol;

[0010] Preferably, the photoinitiator is one or more of acetophenone, 2,4-dihydroxybenzophenone, α,α -diethoxyacetophenone, α -hydroxyalkylphenone, bis(benzoyl phenyl)phosphine oxide, benzoin, benzoin dimethyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin butyl ether.

[0011] Preferably, the molar ratio of the double bond of the cardanol monomer to the mercapto group of the dithiol compound is 1:(0.3 - 1);

[0012] Preferably, the dosage of the photoinitiator is 2wt% - 7wt% of the total amount of the cardanol monomer and the dithiol compound.

[0013] Preferably, the light for the photo-click reaction is ultraviolet light, the wavelength of the ultraviolet light is 365nm, and the time of the photo-click reaction is 12h - 72h;

[0014] Preferably, the temperature of the thermal click reaction is 110°C - 140°C, and the time of the thermal click reaction is 2 - 6h.

[0015] The above method for preparing cardanol-based polyol includes the following steps:

[0016] Mix the cardanol monomer and the dithiol compound evenly, heat at 110°C - 140°C for 2 - 6h, or add a photoinitiator and mix evenly, then stir under ultraviolet light irradiation for 12h - 72h to obtain the cardanol-based polyol.

[0017] A cardanol-based polyurethane foam material, the raw materials are counted by weight, including: 50 - 100 parts of the above cardanol-based polyol, 1 - 3 parts of water, 10 - 50 parts of diol, 0.1 - 1 part of catalyst, 1 - 5 parts of chain extender crosslinking agent, 1 - 3 parts of silicone oil, and 30 - 80 parts of isocyanate.

[0018] Preferably, the diol is one or more of ethylene glycol, propylene glycol, 1,4-butanediol, polyethylene glycol, and polypropylene glycol;

[0019] Preferably, the catalyst is one or more of amine catalysts and organic metal salt catalysts;

[0020] Further preferably, the amine catalyst is one or more of triethylamine, triethylenediamine, N-ethylmorpholine, N-methylmorpholine, triethanolamine, N,N-dimethylcyclohexylamine, and tetramethylbutanediamine; the organometallic salt catalyst is one or more of stannous octoate, dibutyltin dilaurate, dioctyltin dilaurate, zinc isooctoate, and potassium oleate.

[0021] Preferably, the chain extender crosslinking agent is one or more of diethanolamine, triethanolamine, 1,4-butanediol, and 1,4-cyclohexanediol;

[0022] Preferably, the isocyanate is one or more of toluene diisocyanate, polymethylene polyphenyl polyisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and 4,4'-methylenebis(phenyl isocyanate).

[0023] The preparation method of the above-mentioned cardanol-based polyurethane foam material includes the following steps:

[0024] S1: Stir and mix cardanol-based polyol, diol, catalyst, water, silicone oil, and chain extender crosslinking agent evenly to obtain Material A;

[0025] S2: Add isocyanate to Material A and stir evenly to obtain a polyurethane prepolymer;

[0026] S3: Let the obtained polyurethane prepolymer stand and foam at room temperature for 48 - 72 h to obtain cardanol-based polyurethane foam material.

[0027] Preferably, the conditions for stirring in step S1 are: rotation speed 800 - 1400 r / min, time 1 - 5 min, and temperature 20 - 40 °C;

[0028] Preferably, the conditions for stirring in step S2 are: rotation speed 1000 - 2000 r / min, time 2 - 5 min, and temperature 20 - 40 °C.

[0029] Compared with the prior art, the present invention has the following beneficial effects:

[0030] Compared with other bio-based polyurethane foams, the thiol-ene click reaction used in the present invention to synthesize polyol has fewer steps, is simple to operate, consumes less energy, and requires fewer types of raw materials. The bio-based content is relatively large and has a suitable viscosity; the cardanol used contains a benzene ring, and the dithiol compound contains a five-membered ring or an ester group, which can improve the strength or form more hydrogen bonds, resulting in good foam performance and facilitating the substitution of bio-based polyols for traditional petrochemical products. Description of the Drawings

[0031] Figure 1 It is the infrared spectrum of cardanol and the cardanol-based polyols of Examples 1, 2, and 4.

[0032] Figure 2 Thermogravimetric analysis curves of cardanol-based polyurethane foams of Examples 1-7.

[0033] Figure 3 Microscopic pore morphology diagrams of cardanol-based polyurethane foams of Examples 1-7. Detailed implementation manners

[0034] The following drawings and examples are for further illustrating the content of the present invention and should not be construed as limiting the protection scope of the present invention. Without departing from the spirit and essence of the present invention, modifications and substitutions made to the methods, steps or conditions of the present invention all fall within the protection scope of the present invention.

[0035] It should be noted that the unit of the number of parts of substances involved in the following content is mole (mol).

[0036] Example 1

[0037] A preparation method of cardanol-based polyol and polyurethane foam material includes the following steps:

[0038] A cardanol-based polyurethane foam requires the following raw materials: 100 parts of cardanol, 60 parts of ethylene glycol bis(3-mercaptopropionate), 5 parts of benzoin dimethyl ether, 15 parts of water, 30 parts of polypropylene glycol, 0.5 part of dibutyltin dilaurate, 15 parts of 1,4-butanediol, 1 part of silicone oil, and 120 parts of toluene diisocyanate.

[0039] First, weigh the corresponding mass of cardanol and ethylene glycol bis(3-mercaptopropionate), stir to mix them evenly; then add benzoin dimethyl ether, and after mixing evenly, stir under ultraviolet light irradiation for 48 h to obtain cardanol-based polyol.

[0040] The obtained cardanol-based polyol is first stirred and mixed evenly with the corresponding parts of polypropylene glycol, dibutyltin dilaurate, water, silicone oil, and 1,4-butanediol at a rotation speed of 800-1400 r / min to obtain a mixture A material, and then toluene diisocyanate is added and emulsified and stirred evenly at 1000-2000 r / min until the mixed solution turns white to obtain a polyurethane prepolymer; the obtained polyurethane prepolymer is poured into a foaming mold and left to cure at room temperature for 48 h to obtain cardanol-based polyurethane foam.

[0041] Example 2

[0042] A preparation method of cardanol-based polyol and polyurethane foam material includes the following steps:

[0043] A cardanol-based polyurethane foam requires the following raw materials: 100 parts of cardanol, 60 parts of dimercaptothiadiazole, 15 parts of water, 30 parts of polypropylene glycol, 0.5 part of dibutyltin dilaurate, 15 parts of diethanolamine, 1 part of silicone oil, and 120 parts of toluene diisocyanate.

[0044] First, weigh cardanol and dimercaptothiadiazole, add them to a three-necked flask, connect external condensing water and nitrogen, stir for a certain time to mix them evenly, and then stir at 130 °C for 5 h to obtain cardanol-based polyol.

[0045] After the obtained cardanol-based polyol, polypropylene glycol, dibutyltin dilaurate, water, silicone oil, and diethanolamine are stirred and mixed evenly at a rotation speed of 800 - 1400 r / min, toluene diisocyanate is added, and emulsified and stirred evenly at a rotation speed of 1000 - 2000 r / min until the mixture turns white to obtain a polyurethane prepolymer; pour the obtained polyurethane prepolymer into a foaming mold and let it stand at room temperature for 48 h to obtain cardanol-based polyurethane foam.

[0046] Example 3

[0047] A preparation method of cardanol-based polyol and polyurethane foam material includes the following steps:

[0048] A cardanol-based polyurethane foam requires the following raw materials: 100 parts of cardanol, 60 parts of ethylene glycol bis(3-mercaptopropionate), 5 parts of benzoin dimethyl ether, 15 parts of water, 10 parts of polypropylene glycol, 0.5 part of dibutyltin dilaurate, 15 parts of diethanolamine, 1 part of silicone oil, and 120 parts of toluene diisocyanate.

[0049] First, weigh cardanol and ethylene glycol bis(3-mercaptopropionate), stir for a certain time to mix them evenly; then add benzoin dimethyl ether and dissolve it fully, and stir evenly under ultraviolet light irradiation for 48 h to obtain cardanol-based polyol.

[0050] After the obtained cardanol-based polyol, polypropylene glycol, dibutyltin dilaurate, water, silicone oil, and diethanolamine are stirred and mixed evenly at a rotation speed of 800 - 1400 r / min, toluene diisocyanate is added, and emulsified and stirred evenly at a rotation speed of 1000 - 2000 r / min until the mixture turns white; pour the obtained polyurethane prepolymer into a foaming mold and let it stand at room temperature for 48 h to obtain cardanol-based polyurethane foam.

[0051] Example 4

[0052] A preparation method of cardanol-based polyol and polyurethane foam material includes the following steps:

[0053] A cardanol-based polyurethane foam requires the following raw materials: 100 parts of cardanol, 60 parts of 1,4-butanediol bis(mercaptoacetate), 5 parts of benzoin dimethyl ether, 15 parts of water, 30 parts of polypropylene glycol, 0.5 part of dibutyltin dilaurate, 15 parts of diethanolamine, 1 part of silicone oil, and 80 parts of 4,4'-methylenebis(phenyl isocyanate).

[0054] First, weigh cardanol and 1,4-butanediol bis(mercaptoacetate), and stir for a certain time to make them evenly mixed; then add benzoin dimethyl ether and mix evenly, and stir for 48 h under ultraviolet light irradiation to obtain cardanol-based polyol.

[0055] The obtained cardanol-based polyol is mixed evenly with polypropylene glycol, dibutyltin dilaurate, water, silicone oil, and diethanolamine at a rotation speed of 800 - 1400 r / min, then 4,4'-methylenebis(phenyl isocyanate) is added, and it is emulsified and stirred evenly at a rotation speed of 1000 - 2000 r / min until the mixture turns white; the obtained polyurethane prepolymer is poured into a foaming mold and left to stand at room temperature for 48 h to obtain cardanol-based polyurethane foam.

[0056] Example 5

[0057] A preparation method of cardanol-based polyol and polyurethane foam material, comprising the following steps:

[0058] A cardanol-based polyurethane foam requires the following raw materials: 100 parts of cardanol, 60 parts of 1,4-butanediol bis(mercaptoacetate), 5 parts of benzoin dimethyl ether, 15 parts of water, 30 parts of polyethylene glycol, 0.5 part of dibutyltin dilaurate, 15 parts of diethanolamine, 1 part of silicone oil, and 80 parts of isophorone diisocyanate.

[0059] First, weigh cardanol and 1,4-butanediol bis(mercaptoacetate), and stir for a certain time to make them evenly mixed; then add benzoin dimethyl ether and mix evenly, and stir for 48 h under ultraviolet light irradiation to obtain cardanol-based polyol.

[0060] The obtained cardanol-based polyol is mixed evenly with polyethylene glycol, dibutyltin dilaurate, water, silicone oil, and diethanolamine at a rotation speed of 800 - 1400 r / min, then isophorone diisocyanate is added, and it is emulsified and stirred evenly at a rotation speed of 1000 - 2000 r / min until the mixture turns white; the obtained polyurethane prepolymer is poured into a foaming mold and left to stand at room temperature for 48 h to obtain cardanol-based polyurethane foam.

[0061] Example 6

[0062] A preparation method of cardanol-based polyol and polyurethane foam material, comprising the following steps:

[0063] A cardanol-based polyurethane foam requires the following raw materials: 100 parts of cardanol, 60 parts of ethylene glycol bis(3-mercaptopropionate), 5 parts of benzoin dimethyl ether, 15 parts of water, 10 parts of polyethylene glycol, 0.5 part of dibutyltin dilaurate, 15 parts of diethanolamine, 1 part of silicone oil, and 60 parts of 4,4'-methylenebis(phenyl isocyanate).

[0064] First, weigh cardanol and ethylene glycol bis(3-mercaptopropionate), and stir for a certain time to make them mix evenly; then add benzoin dimethyl ether and mix evenly, and stir for 48 h under ultraviolet light irradiation to obtain cardanol-based polyol.

[0065] The obtained cardanol-based polyol is mixed evenly with polyethylene glycol, dibutyltin dilaurate, water, silicone oil, and diethanolamine at a rotation speed of 800-1400 r / min, then 4,4'-methylenebis(phenyl isocyanate) is added, and emulsified and stirred evenly at a rotation speed of 1000-2000 r / min until the mixture turns white; the obtained polyurethane prepolymer is poured into a foaming mold and left standing at room temperature for 48 h to obtain cardanol-based polyurethane foam.

[0066] Example 7

[0067] A preparation method of cardanol-based polyol and polyurethane foam material includes the following steps:

[0068] A cardanol-based polyurethane foam requires the following raw materials: 100 parts of cardanol, 60 parts of 1,4-butanediol bis(mercaptoacetate), 5 parts of benzoin dimethyl ether, 15 parts of water, 10 parts of polyethylene glycol, 0.5 part of dibutyltin dilaurate, 15 parts of 1,4-butanediol, 1 part of silicone oil, and 60 parts of toluene diisocyanate.

[0069] First, weigh cardanol and 1,4-butanediol bis(mercaptoacetate), and stir for a certain time to make them mix evenly; then add benzoin dimethyl ether and mix evenly, and stir for 48 h under ultraviolet light irradiation to obtain cardanol-based polyol.

[0070] The obtained cardanol-based polyol is mixed evenly with polyethylene glycol, dibutyltin dilaurate, water, silicone oil, and 1,4-butanediol at a rotation speed of 800-1400 r / min, then toluene diisocyanate is added, and emulsified and stirred evenly at a rotation speed of 1000-2000 r / min until the mixture turns white; the obtained polyurethane prepolymer is poured into a foaming mold and left standing at room temperature for 48 h to obtain cardanol-based polyurethane foam.

[0071] Data analysis:

[0072] Figure 1Infrared spectra of cardanol (1005A) and cardanol-based polyols (Sample2, 1, 3) of Examples 1, 2, and 4. It can be seen from the figure that the peaks of carbon-carbon double bonds at 3010 cm -1 of the cardanol-based polyols in Examples 1, 2, and 4 are significantly weakened, indicating that the thiol group reacts with the double bond after ultraviolet light irradiation.

[0073] Table 1 shows the hydroxyl values and viscosities of the cardanol-based polyols in Examples 1, 2, and 4. It can be seen that due to the benzene ring carried by cardanol, the viscosities of the cardanol-based polyols are relatively high; due to the rigid five-membered ring contained in 2,5-dimercapto-1,3,4-thiadiazole in Example 2, the viscosity is the highest.

[0074] Figure 2 Thermogravimetric analysis curves of cardanol-based polyurethane foams of Examples 1-7. It can be seen that the 5% thermal decomposition temperatures of several cardanol-based polyurethane foams are all above 210 °C, showing good thermal stability.

[0075] Figure 3 Microscopic pore morphology diagrams of cardanol-based polyurethane foams of Examples 1-7. It can be seen from the figure that the sizes and shapes of the pores are relatively uniform, with an average diameter of about 200 μm, and the shapes are mostly oval or polygonal closed pores.

[0076] Table 2 shows the performance data of cardanol-based polyurethane foams of Examples 1-7. It can be seen that the polyurethanes prepared from polyols synthesized by photo-click reaction in Examples 1, 3, 4, 5, 6, and 7 have relatively good mechanical properties. The reason may be that the dithiol compounds used in the photo-click reaction contain ester groups, which can form hydrogen bonds with urethane; the elongation at break of the polyurethane prepared from polyols synthesized by thermal click reaction system in Example 2 is relatively low. The reason may be that too many five-membered and six-membered rings in the main chain make the molecular chain too rigid, resulting in brittle products.

[0077] Table 1 Physical Property Parameters of Cardanol-based Polyols

[0078]

[0079] Table 2 Properties of Cardanol-based Polyurethane Foam Materials

[0080]

[0081]

Claims

1. A cardanol-based polyol, characterized in that: The cardanol-based polyol is synthesized by using cardanol monomers and dithiol compounds as reaction raw materials, through a thermal click reaction of thiol-ene under heating conditions or a photo-click reaction initiated by a photoinitiator under light.

2. The cardanol-based polyol according to claim 1, characterized in that: The cardanol monomer is one or more of cardanol and cardanol derivatives containing multiple unsaturated double bonds; The bis-mercapto compound is one or more of bis(thioglycolic acid) glycol ester, 1,4-benzenedimethanethiol, 1,4-butanediol bis(thioglycolic acid ester), dithiothiadiazole, bis(3-mercaptopropionic acid) glycol ester, and 2,3-dithio(2-mercapto)-1-propanethiol; The photoinitiator is one or more of diphenylacetophenone, 2,4-dihydroxybenzophenone, α,α-diethoxyacetophenone, α-hydroxyalkylbenzophenone, bisbenzoylphenylphosphine oxide, benzoin, benzoin dimethyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin butyl ether.

3. The cardanol-based polyol according to claim 1, characterized in that: The molar ratio of the double bond of the cardanol monomer to the thiol group of the dithiol compound is 1:(0.3-1); The amount of the photoinitiator used is 2wt% to 7wt% of the total amount of the cardanol monomer and the bis-thiol compound.

4. The cardanol-based polyol according to claim 1, characterized in that: The light for the photo-click reaction is ultraviolet light, the wavelength of the ultraviolet light is 365nm, and the time for the photo-click reaction is 12h to 72h; The temperature of the hot click reaction is 110°C to 140°C, and the time of the hot click reaction is 2 to 6 hours.

5. The method for preparing the cardanol-based polyol according to any one of claims 1 to 4, characterized in that: The following steps are involved: The cardanol monomer and the dithiol compound are mixed evenly, heated at 110° C. to 140° C. for 2 to 6 hours, or a photoinitiator is added and mixed evenly, and then stirred under ultraviolet light for 12 to 72 hours to obtain the cardanol-based polyol.

6. A cardanol-based polyurethane foam material, characterized in that: The raw materials include, by weight: 50 to 100 parts of the cardanol-based polyol according to any one of claims 1 to 4, 1 to 3 parts of water, 10 to 50 parts of diols, 0.1 to 1 part of a catalyst, 1 to 5 parts of a chain extender and cross-linking agent, 1 to 3 parts of silicone oil, and 30 to 80 parts of isocyanate.

7. The cardanol-based polyurethane foam material according to claim 6, characterized in that: The diol is one or more of ethylene glycol, propylene glycol, 1,4-butanediol, polyethylene glycol, and polypropylene glycol; The catalyst is one or more of an amine catalyst and an organic metal salt catalyst; The chain extending cross-linking agent is one or more of diethanolamine, triethanolamine, 1,4-butanediol, and 1,4-cyclohexanediol; The isocyanate is one or more of toluene diisocyanate, polymethylene polyphenyl polyisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and 4,4'-methylene bis(phenyl isocyanate).

8. The cardanol-based polyurethane foam material according to claim 7, characterized in that: The amine catalyst is one or more of triethylamine, triethylenediamine, N-ethylmorpholine, N-methylmorpholine, triethanolamine, N,N-dimethylcyclohexylamine, and tetramethylbutylene diamine; the organic metal salt catalyst is one or more of stannous octoate, dibutyltin dilaurate, dioctyltin dilaurate, zinc isooctanoate, and potassium oleate.

9. The method for preparing the cardanol-based polyurethane foam material according to any one of claims 6 to 8, characterized in that: The steps include: S1: Mix the cardanol-based polyol with diol, catalyst, water, silicone oil and chain extender cross-linking agent to obtain material A; S2: adding isocyanate to material A and stirring evenly to obtain a polyurethane prepolymer; S3: The obtained polyurethane prepolymer is allowed to foam at room temperature for 48 to 72 hours to obtain a cardanol-based polyurethane foam material.

10. The preparation method according to claim 9, characterized in that: The stirring conditions in step S1 are: a rotation speed of 800 to 1400 r / min, a time of 1 to 5 min, and a temperature of 20 to 40° C.; The stirring conditions in step S2 are: a rotation speed of 1000-2000 r / min, a time of 2-5 min, and a temperature of 20-40° C.

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