Lignin-based diphenylmethane diisocyanate and preparation method and application thereof
阅读说明：本技术 一种木质素基二苯基甲烷二异氰酸酯及其制备方法与应用 (Lignin-based diphenylmethane diisocyanate and preparation method and application thereof ) 是由 应汉杰 黎明晖 沈涛 朱晨杰 胡瑞佳 庄伟� 李明 陈彦君 柳东 牛欢青 杨朋朋 于 2021-08-11 设计创作，主要内容包括：本发明公开了一种木质素基二苯基甲烷二异氰酸酯及其制备方法与应用,所述木质素基二苯基甲烷二异氰酸酯如式Ⅰ所示,其制备方法为木质素裂解单体化合物II与羰基化合物经羟烷基化反应得到化合物III,化合物III与氯乙酰氨经氨化反应得到化合物IV,化合物IV经Smiles重排反应得到化合物V,化合物V与含碳酸基的化合物反应得到式Ⅰ所示的木质素基二苯基甲烷二异氰酸酯。本发明产品代替MDI用于聚氨酯材料的合成,提高了聚氨酯材料的韧性、热稳定性和玻璃化温度；用于聚氨酯防水涂料应用时,吸水率明显下降,涂料的稳定性也得到提高。(The invention discloses lignin-based diphenylmethane diisocyanate and a preparation method and application thereof, wherein the lignin-based diphenylmethane diisocyanate is shown as a formula I, the preparation method comprises the steps of carrying out a hydroxyl alkylation reaction on a lignin cracking monomer compound II and a carbonyl compound to obtain a compound III, carrying out an ammoniation reaction on the compound III and chloroacetamide to obtain a compound IV, carrying out a Smiles rearrangement reaction on the compound IV to obtain a compound V, and carrying out a reaction on the compound V and a carbonic acid group-containing compound to obtain the lignin-based diphenylmethane diisocyanate shown as the formula I. The product of the invention replaces MDI to be used for the synthesis of polyurethane materials, and improves the toughness, the thermal stability and the glass transition temperature of the polyurethane materials; when the water-absorbing polyurethane coating is used for polyurethane waterproof coating, the water absorption rate is obviously reduced, and the stability of the coating is also improved.)
1. Lignin-based diphenylmethane diisocyanate shown as a formula I;
wherein the content of the first and second substances,
R1selected from H, CH3Or OCH3；
R2Is selected from CH3、CH2CH3Or CH2CH2CH3；
R3And R4Each independently selected from H or CH3。
2. The preparation method of the lignin-based diphenylmethane diisocyanate according to claim 1, wherein the lignin cleavage monomer compound II and the carbonyl compound are subjected to a hydroxyalkylation reaction to obtain a compound III, the compound III and chloroacetamide are subjected to an amination reaction to obtain a compound IV, the compound IV is subjected to a Smiles rearrangement reaction to obtain a compound V, and the compound V is reacted with a compound containing a carbonic acid group to obtain the lignin-based diphenylmethane diisocyanate represented by the formula I;
wherein the content of the first and second substances,
R1selected from H, CH3Or OCH3；
R2Is selected from CH3、CH2CH3Or CH2CH2CH3；
R3And R4Each independently selected from H or CH3。
3. The preparation method according to claim 2, wherein the carbonyl compound is any one or combination of formaldehyde, acetaldehyde and acetone; the molar ratio of the lignin cracking monomer compound II to the carbonyl compound is 2: (1-1.5).
4. The method of claim 2, wherein the hydroxyalkylation reaction further comprises an acid catalyst, and the acid catalyst is p-toluenesulfonic acid, H2SO4HCl, Amberlyst 15, Nafion SAC-13, alumina, zeolite Y and H4SiW12O40Any one or combination of a plurality of the above; preferably, the temperature of the hydroxyalkylation reaction is between 40 and 80 ℃.
5. The method according to claim 2, wherein the catalyst for the amination is potassium carbonate and/or potassium iodide; the solvent of the ammoniation reaction is any one or combination of more of acetone, butanone, ethanol, N-dimethylformamide, cyclohexanone, dioxane, tetrahydrofuran and acetonitrile; preferably, the temperature of the amination reaction is between 40 ℃ and reflux temperature.
6. The preparation method according to claim 2, wherein the catalyst for the Smiles rearrangement reaction is any one or a combination of potassium hydroxide, cesium hydroxide and sodium hydride.
7. The process according to claim 2, wherein the solvent for the Smiles rearrangement reaction is dimethyl sulfoxide and/or N, N-dimethylpropyleneurea; preferably, the temperature of the Smiles rearrangement reaction is 120-200 ℃.
8. The method according to claim 2, wherein the carbonic acid group-containing compound is any one or a combination of triphosgene and dimethyl carbonate.
9. Use of the lignin-based diphenylmethane diisocyanate according to claim 1 in the preparation of polyurethane materials.
10. The application of the polyurethane material as claimed in claim 12, wherein the polyurethane material is prepared by mixing polypropylene glycol and lignin-based diphenylmethane diisocyanate for reaction; the molar ratio of-OH in the polypropylene glycol to-NCO in the lignin-based diphenylmethane diisocyanate is 1: (1.2-1.5); preferably, the temperature of the reaction is 70-90 ℃.
Technical Field
The invention belongs to the field of bio-based high polymer materials, and particularly relates to lignin-based diphenylmethane diisocyanate and a preparation method and application thereof.
Background
Lignin is widely present in fern plants and all higher plants in nature, forms the main component of the plant skeleton together with cellulose and hemicellulose, and plays the dual roles of bonding fibers and stiffening the fibers. In nature, lignin is produced very abundantly annually, second in the line, next to cellulose. Under the influence of the biosynthetic process, lignin molecules are very complex in chemical structure, unlike cellulose, which has repeating structural units. It is generally recognized as a high molecular polymer with a three-dimensional network structure formed by connecting three phenylpropane units through ether bonds and carbon-carbon bonds, wherein the three phenylpropane units are respectively guaiacyl propane (G type), syringyl propane (S type) and p-hydroxyphenyl propane (H type). The lignin molecules have a plurality of functional groups such as aromatic groups, methoxyl groups, phenolic (alcoholic) hydroxyl groups, carbonyl groups, carboxyl groups and the like, active sites such as unsaturated double bonds and the like, and the content ratio of C/H and C/O which is similar to that of petroleum, so that the lignin molecules are expected to become main renewable raw materials for producing high-grade biofuel oil such as aromatic hydrocarbon, cyclane, alkane and the like, and aromatic chemicals with high added values such as phenols and the like. As the only renewable non-fossil resource capable of providing aromatic compounds in the nature, the production of aromatic chemicals by lignin degradation is undoubtedly an ideal way for the high-value utilization of lignin in the future. For example, Borregaard, Norway, developed processes for the production of vanillin from lignin or lignosulfonate, which became the second largest vanillin manufacturer worldwide and the largest vanillin supplier in Europe.
Catalytic hydrodepolymerization of lignin refers to the catalytic depolymerization of lignin achieved in the presence of an external hydrogen molecule or in situ hydrogen source. The hydrotreating of lignin was proposed in the early days mainly for the hydrodeoxygenation of lignin pyrolysis bio-oil, and in recent years, the direct preparation of aromatic products by depolymerization of lignin under hydrogenation conditions has become a focus of research. The selection of the catalytic center is the key of the depolymerization effect, and the common catalytic center comprises noble metals, transition metals and the like. In the noble metal field, palladium, molybdenum, ruthenium, and the like have been studied. Under the action of noble metal catalyst, the reaction can be completed in lower reaction temperature and shorter reaction time, and lignin is depolymerized to generate a series of phenolic products, and in some cases, monophenol products may undergo further aromatic ring hydrogenation reaction. By selecting different catalysts, solvents, hydrogen pressure, temperature, reaction time and the like, lignin can be degraded to obtain lignin aromatic compound monomers: vanillin, propyl guaiacol, eugenol, isoeugenol, ethyl guaiacol, methyl guaiacol, 3-propanol guaiacol, p-propyl phenol, syringol, etc. Song et al, by DaLianlian of Chinese academy of sciences, carbothermic reduction is adopted for a Ni catalyst, so that part of the activated carbon carrier is oxidized into carbon oxides, the degree of bond breaking of the catalyst on C-O bonds reaches 99%, and researches on the depolymerization effect of lignin in birch by the Ni catalyst show that under the action of the Ni-based catalyst in a methanol environment, about 54% of lignin can be degraded, and the total selectivity of propyl guaiacol and propyl syringol in the product can reach more than 90%.
Polyurethane is a polymer material containing repeated carbamate chain segments (-NHCOO-) in a molecular structure, is known to have the characteristics of higher strength, excellent elasticity, oil resistance, low temperature resistance and the like, and a polyurethane elastomer is widely applied to various industries as a novel polymer synthetic material. The polyurethane synthesis process is based on the isocyanate chemical reaction, the most important of which is the reaction of isocyanate with an active hydrogen compound, which is a stepwise addition polymerization with hydrogen transfer. Isocyanates can be classified into aliphatic and aromatic groups according to their structures. Toluene Diisocyanate (TDI) and diphenylmethane diisocyanate (MDI, the structural formula is shown in figure 1) are two common aromatic isocyanates, and industrial production is realized by a plurality of famous chemical enterprises at home and abroad, so that the price is relatively low.
Among them, MDI is the isocyanate with the largest output and the widest application, has excellent performance and is easy to store. MDI can be classified into polymeric grade, mixed grade (dimer and trimer blend) and pure monomer 3 grades depending on the degree of polymerization of the molecule. The MDI pure monomer (or called pure MDI) is mainly used for synthetic leather sizing agent, sole stock solution and spandex; the polymeric MDI is mainly used for building, various industrial molding and refrigeration, and the polyurethane rigid foam taking the polymeric MDI as a main raw material is a building energy-saving material with excellent performance which is globally acknowledged at present. The current commercial products are mainly based on pure MDI and polymeric MDI, wherein the polymeric MDI accounts for about 80 percent of the total market demand.
The invention synthesizes the lignin-based MDI by taking the lignin monomer as the initial raw material, thereby avoiding the dependence on fossil resources caused by the traditional MDI production; meanwhile, the unique side chain groups such as alkyl, methoxyl, olefin and the like in the molecular structure of the lignin-based MDI and the special molecular structure endow the polyurethane material with new characteristics, improve the toughness, the thermal stability and the glass transition temperature of the polyurethane, and widen the application range of the MDI-based polyurethane material.
Disclosure of Invention
The purpose of the invention is as follows: the invention aims to solve the technical problem of providing lignin-based MDI shown as a formula I aiming at the defects of the prior art.
The technical problem to be solved by the invention is to provide the preparation method of the lignin-based MDI.
The technical problem to be solved by the present invention is to provide the use of the above-mentioned lignin-based MDI.
In order to solve the first technical problem, the invention discloses lignin-based MDI shown as a formula I;
wherein the content of the first and second substances,
R1selected from H, CH3Or OCH3；
R2Is selected from CH3、CH2CH3Or CH2CH2CH3；
R3And R4Each independently selected from H or CH3。
Preferably, the lignin-based MDI is any one of formula i1 to formula i 27 (table 1).
TABLE 1 (formula I1-formula I27)
。
In order to solve the second technical problem, the present invention discloses a method for preparing the above-mentioned lignin-based MDI, as shown in fig. 2, comprising the steps of:
(1) carrying out a hydroxyl alkylation reaction on the lignin cracking monomer compound II and a carbonyl compound to obtain a compound III;
(2) carrying out ammoniation reaction on the compound III and chloroacetamide to obtain a compound IV;
(3) carrying out Smiles rearrangement reaction on the compound IV to obtain a compound V;
(4) reacting the compound V with a compound containing carbonic acid groups to obtain lignin-based MDI shown in the formula I;
wherein the content of the first and second substances,
R1selected from H, CH3Or OCH3；
R2Is selected from CH3、CH2CH3Or CH2CH2CH3；
R3And R4Each independently selected from H or CH3。
In the step (1), the carbonyl compound is any one or a combination of formaldehyde, acetaldehyde and acetone.
Wherein the molar ratio of the lignin cracking monomer compound II to the carbonyl compound is 2: (1-1.5).
In step (1), the hydroxyalkylation reaction further comprises an acid catalyst.
Wherein the acid catalyst is p-toluenesulfonic acid and H2SO4HCl, Amberlyst 15, Nafion SAC-13, alumina, zeolite Y and H4SiW12O40Any one or combination of a plurality of the above; preferably, the acid catalyst is p-toluenesulfonic acid; wherein, the H2SO4Preferably 98% H2SO4(ii) a The HCl is preferably 5M HCl.
Wherein the mass ratio of the lignin cracking monomer compound II to the acid catalyst is 2: (0.01-2); preferably, the mass ratio of the lignin cracking monomer compound II to the acid catalyst is 2: (0.1-1)
In the step (1), the temperature of the hydroxyalkylation reaction is 40-80 ℃.
In the step (1), the time of the hydroxyalkylation reaction is 0.5-6 h.
In the step (2), the molar ratio of the compound III to chloroacetamide is 1: (1-1.5).
In the step (2), the catalyst for the ammoniation reaction is potassium carbonate and/or potassium iodide; preferably, the catalyst is a combination of potassium carbonate and potassium iodide; further preferably, the catalyst is potassium carbonate and potassium iodide in a molar ratio of (22-25): 1 in combination.
Wherein in the ammoniation reaction, the mol ratio of the compound II to the catalyst is (1.5-3): 1.
in the step (2), the solvent for the ammoniation reaction is any one or a combination of more of acetone, butanone, ethanol, N-dimethylformamide, cyclohexanone, dioxane, tetrahydrofuran and acetonitrile; preferably, the solvent is acetone.
In the step (2), the mol volume ratio of the chloracetamide to the solvent is 1-1.5 mol: 30L; preferably, the molar volume ratio of chloroacetamide to solvent is 1.25 mol: 30L.
In the step (2), the temperature of the ammoniation reaction is 40-reflux temperature; preferably, the temperature of the amination reaction is between 50 and 70 ℃.
In the step (2), the ammoniation reaction time is 6-24 h.
In the step (3), the catalyst for the Smiles rearrangement reaction is any one or combination of potassium hydroxide, cesium hydroxide and sodium hydride.
Wherein the molar ratio of the catalyst to the compound IV in the Smiles rearrangement reaction is (1.5-4): 1.
in the step (3), the solvent for the Smiles rearrangement reaction is dimethyl sulfoxide (DMSO) and/or N, N-Dimethylpropyleneurea (DMPU); preferably, the solvent is a mixture of DMSO and DMPU; further preferably, the solvent is DMSO and DMPU according to the volume ratio of (3-1): 1 and mixing.
Wherein the molar volume ratio of the compound IV to the solvent in the Smiles rearrangement reaction is 1 mmol: (10-30) mL.
In the step (3), the temperature of the Smiles rearrangement reaction is 120-200 ℃.
In the step (3), the time of the Smiles rearrangement reaction is 0.5-6 h.
In the step (4), the carbonic acid group-containing compound is triphosgene (BTC) and/or dimethyl carbonate.
Wherein, when the carbonic acid group-containing compound is triphosgene, the reaction is a reaction of a chlorobenzene solution of the compound V with triphosgene (BTC); preferably, a chlorobenzene solution of triphosgene is added to a chlorobenzene solution of compound V into which dry hydrogen chloride gas is introduced to carry out the reaction.
Wherein the dosage ratio of the compound V to chlorobenzene in the chlorobenzene solution of the compound V is 1 mmol: (10-30) mL; preferably, the dosage ratio of the compound V to chlorobenzene in the chlorobenzene compound solution is 1 mmol: 20 mL.
Wherein in the chlorobenzene solution of the triphosgene, the dosage ratio of the triphosgene to the chlorobenzene is 1 mmol: (10-30) mL; preferably, in the chlorobenzene solution of triphosgene, the ratio of the amount of triphosgene to chlorobenzene is 1 mmol: 20 mL.
Wherein the molar ratio of the compound V to the triphosgene is (1-2): 1.
wherein the reaction temperature is 110-130 ℃.
Wherein the reaction time is 4-10 h.
When the compound containing the carbonic acid group is dimethyl carbonate, the reaction is to perform a first reaction on a compound V and dimethyl carbonate (DMC), a reaction solution is washed to be neutral by water, the reaction solution is filtered, filter residues are recrystallized to obtain an intermediate lignin-based diphenylmethane dicarbamate (lignin-based MDC), and the collected intermediate (lignin-based MDC) is put into a high vacuum reactor to perform a second reaction, namely, the final product lignin-based MDI is obtained under high temperature cracking.
Wherein in the first reaction, the molar ratio of the compound V to dimethyl carbonate (DMC) is 1: (4-8); preferably, the molar ratio of compound V to dimethyl carbonate (DMC) is 1: 6.
wherein, the first reaction also comprises a catalyst, and the catalyst comprises but is not limited to sodium methoxide; preferably, the molar ratio of the catalyst to compound V is between 0.5% and 1.5%; further preferably, the molar ratio of the catalyst to compound V is 1%.
Wherein the temperature of the first reaction is 110-130 ℃.
Wherein the time of the first reaction is 4-10 h.
Wherein the second reaction further comprises a catalyst including, but not limited to, zinc acetate; preferably, the mass ratio of the catalyst to the lignin-based MDC is 1: (20-80); further preferably, the mass ratio of the catalyst to the lignin-based MDC is 1: 50.
wherein the solvent of the second reaction is tetrafluoroboric acid and/or N-methyl-N-carbethoxymorpholine acetate; preferably, the mass ratio of the solvent to the lignin-based MDC is 3: 1; further preferably, the mass ratio of the solvent to the lignin-based MDC is (1-5): 1.
wherein the temperature of the second reaction is 180-250 ℃.
In order to solve the third technical problem, the invention discloses application of the lignin-based MDI in preparing a polyurethane material.
Wherein the polyurethane material is a polyurethane waterproof coating.
The preparation method of the polyurethane material comprises the steps of mixing polypropylene glycol and lignin-based MDI to carry out a first reaction; preferably, the polypropylene glycol is polypropylene glycol N220.
Wherein the molar ratio of-OH in the polypropylene glycol to-NCO in the lignin-based MDI is 1: (1.2-1.5).
Wherein the temperature of the first reaction is 70-90 ℃.
Wherein the time of the first reaction is 1-3 h.
And after the first reaction is finished, cooling, adding dimethylolpropionic acid for a second reaction, adding a chain extender for a third reaction, cooling again, neutralizing, and emulsifying to obtain the water-soluble polyurethane emulsion.
Wherein the temperature reduction is to be carried out to 60-90 ℃.
Wherein the time of the second reaction is 0.5-1.5 h.
Wherein the chain extender is 1, 4-butanediol and/or stannous octoate; preferably, the chain extender is 1, 4-butanediol and stannous octoate; further preferably, the molar ratio of 1, 4-butanediol to stannous octoate in the chain extender is 1: (0.01-0.1); still more preferably, the molar ratio of 1, 4-butanediol to stannous octoate in the chain extender is 1: 0.05.
wherein the molar ratio of the chain extender to-OH in the polypropylene glycol is (0.1-0.3): 1.
wherein, the temperature is reduced to below 40 ℃ again.
Wherein the neutralization is realized by adding triethylamine, and the neutralization degree is 120%.
Has the advantages that: compared with the prior art, the invention has the following advantages:
1. the method utilizes the green sustainable lignin as the raw material, and reduces the dependence on fossil resources.
2. According to the method, the lignin-based MDI is synthesized from lignin monomers through a hydroxyalkylation-chloroacetylamide-Smiles rearrangement-triphosgene method path, separation and purification are not needed after the hydroxyalkylation reaction is finished, and a crude product is subjected to chloroacetylamide reaction and then can be subjected to simple solid-liquid separation to obtain a pure compound IV.
3. The Smiles rearrangement reaction adopts microwave assistance, overcomes the defects of low reactivity and low yield of electron donating groups, and has high reaction selectivity and yield.
4. The product of the invention replaces MDI to be used for the synthesis of polyurethane materials, and improves the toughness, the thermal stability and the glass transition temperature of the polyurethane materials; when the water-absorbing polyurethane coating is used for polyurethane waterproof coating, the water absorption rate is obviously reduced, and the stability of the coating is also improved.
Drawings
The foregoing and/or other advantages of the invention will become further apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings.
FIG. 1 is a schematic diagram of the structure of diphenylmethane diisocyanate (MDI).
FIG. 2 is a synthetic route for the lignin-based MDI of the present invention.
FIG. 3 is R1And R2Of compound III in the case of methoxy and propyl radicals respectively1H NMR；1H NMR(400MHz,DMSO)δ＝8.56(s,2H),6.71(s,2H),6.31(s,2H),3.73(s,6H),3.67(s,2H),2.46–2.37(m,2H),1.49(dd,J＝15.3,7.5,2H),0.90(t,J＝7.3,3H).
FIG. 4 is R1And R2Mass spectrum of compound III for methoxy and propyl, respectively.
FIG. 5 is R1And R2Of compounds IV, independently of methoxy and propyl1H NMR；1H NMR(400MHz,DMSO)δ＝7.28(d,J＝31.4,4H),6.82(s,2H),6.47(s,2H),4.24(s,4H),3.78(s,8H),3.77(s,1H),2.50–2.38(m,4H),1.49(dd,J＝15.3,7.5,4H),0.89(t,J＝7.3,6H).
FIG. 6 is R1And R2Of compounds IV, independently of methoxy and propyl13C NMR；13C NMR(101MHz,DMSO)δ＝170.73,147.95,145.60,134.59,130.70,117.26,114.18,69.07,56.13,34.61,34.23,24.15,14.43.
FIG. 7 is R1And R2Of compounds V in the case of methoxy and propyl radicals respectively1H NMR；1H NMR(400MHz,DMSO)δ＝6.58(s,2H),6.19(s,2H),4.35(s,4H),3.73(s,6H),3.61(s,3H),2.45–2.30(m,4H),1.48(dq,J＝14.8,7.3,4H),0.89(t,J＝7.3,6H).
FIG. 8 is R1And R2Of compounds V in the case of methoxy and propyl radicals respectively13C NMR；13C NMR(75MHz,DMSO)δ＝145.11,135.17,131.12,128.42,116.05,112.16,55.69,34.81,34.04,24.62,14.50.
Detailed Description
The experimental methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.
Example 1:
IIIA 2,2' -methylene (4-methylphenol)
Accurately weighing 4-methylphenol (21.6g, 0.2mol), 40% formaldehyde solution (9.0g, 0.12mol) and p-toluenesulfonic acid (1.72g, 0.01mol) in a pressure-resistant bottle, stirring for 30 minutes under heating in a water bath at 60 ℃, diluting with ethyl acetate after the reaction is finished, extracting with water and ethyl acetate, drying with anhydrous magnesium sulfate and concentrating an organic phase to obtain a viscous oily liquid (compound IIIA), wherein the yield reaches 80.3%. MSI-MS 229.3[ M + H ]]+。
IVA 2,2' - ((methylene (4-methyl-2, 1-phenyl)) bis ((oxy)) bisacetamide
IIIA (11.4g, 0.05mol), chloroacetamide (5.8g, 0.0625mol), anhydrous potassium carbonate (15.5g, 0.1125mol), potassium iodide (0.83g, 0.005mol) were weighed accurately into a 2L round bottom flask, 1.25L acetone was added, stirred at 60 ℃ for 6h, and reactedAfter the reaction was completed, filtration was carried out, the filtrate was spin-dried, extracted with water and ethyl acetate, dried over anhydrous magnesium sulfate and the organic phase was concentrated and recrystallized to obtain white crystals (compound IVA) with a yield of 99.6%. MSI-MS 343.4[ M + H]+。
VA 2,2' -methylene (4-methylaniline)
Accurately weighing IVA (3.42g and 10mmol) and potassium hydroxide (2.24g and 40mmol) in a microwave reaction bottle, adding 150mL of dimethyl sulfoxide (DMSO) and 50mL of N, N-dimethyl propylene urea (DMPU), heating for 2h at 180 ℃, extracting with water and ethyl acetate after the reaction is finished, drying by anhydrous magnesium sulfate, concentrating an organic phase, and separating and purifying by column chromatography (ethyl acetate/N-hexane) to obtain the yield of 98.5%. MSI-MS 227.3[ M + H]+。
I-1 bis (2-isocyanato-5-methylphenyl) methane
After a spherical condenser, a thermometer, and a nitrogen introduction tube were connected to a 500mL four-necked reaction flask, VA (1.39g, 5mmol) and 100mL chlorobenzene were accurately weighed and stirred until they were completely dissolved. Introducing dry hydrogen chloride gas for 3h, dropwise adding a chlorobenzene solution (100mL) of triphosgene (BTC, 1.48g and 5mmol) into the reaction bottle within 1h, continuously stirring, heating to 120 ℃, purging the reaction bottle with 10mL/min nitrogen gas for 6h, and absorbing tail gas with alkali liquor. After the reaction is finished, cooling to room temperature, continuously introducing nitrogen for 30min, filtering to remove filter residues, and distilling under reduced pressure to remove the solvent, wherein the yield reaches 92%. MSI-MS 279.3[ M + H ]]+。
Example 2:
2A 6,6' -methylene (2, 4-dimethylphenol)
Referring to the IIIA synthesis method, 2, 4-dimethylphenol was used instead of 4-methylphenol, and the yield reached 80.5%. MSI-MS 257.4[ M + H]+。
2B 2,2' - ((methylene (4, 6-dimethyl-2, 1-phenyl)) bis ((oxy)) bisacetamide
Referring to the IVA synthesis method, the yield reaches 98.9%. MSI-MS 371.5[ M + H ]]+。
2C 6,6' -methylene (2, 4-dimethylaniline)
Referring to the VA synthesis method, the yield reaches 98.4%. MSI-MS 255.4[ M + H]+。
I-2 bis (2-isocyanato-3, 5-dimethylphenyl) methane
Referring to the synthesis method of I-1, the yield reaches 93.2 percent. MSI-MS 307.4[ M + H ]]+。
Example 3:
3A 6,6' -methylene (2-methoxy-4-methylphenol)
Referring to the IIIA synthesis method, 4-methyl-2-methoxyphenol is used to replace 4-methylphenol, and the yield reaches 79.2%. MSI-MS 289.3[ M + H ]]+。
3B 2,2' - ((methylene (6-methoxy-4-methyl-2, 1-phenyl)) bis ((oxy)) bisacetamide
Referring to the IVA synthesis method, the yield is 96.4%. MSI-MS 403.4[ M + H]+。
3C 6,6' -methylene (2-methoxy-4-methylaniline)
Referring to the VA synthesis method, the yield reaches 97.6 percent. MSI-MS 287.3[ M + H]+。
I-3 bis (2-isocyanato-3-methoxy-5-methylphenyl) methane
Referring to the synthesis method of I-1, the yield reaches 93.6 percent. MSI-MS 339.4[ M + H]+。
Example 4:
4A 2,2' - (propane-2, 2-diyl) bis (4-methylphenol)
Referring to the IIIA synthesis method, acetaldehyde is used to replace formaldehyde, and the yield reaches 78.4%. MSI-MS 243.3[ M + H]+。
4B 2,2' - ((ethane-1, 1-diylbis (4-methyl-2, 1-phenylene)) bis (oxy)) diacetic acid amide
Referring to the IVA synthesis method, the yield is 94.2%. MSI-MS 357.4[ M + H]+。
4C 2,2' - (propane-2, 2-diyl) bis (4-methylaniline)
Referring to the VA synthesis method, the yield reaches 95.3 percent. MSI-MS 241.3[ M + H ]]+。
I-42, 2' - (ethane-1, 1-diyl) bis (1-isocyanato-4-methylbenzene)
Referring to the synthesis method of I-1, the yield reaches 92.3 percent. MSI-MS 293.3[ M + H ]]+。
Example 5:
5A 6,6' - (ethane-1, 1-diyl) bis (2, 4-dimethylphenol)
Referring to the IIIA synthesis method, 2, 4-dimethylphenol is used for replacing 4-methylphenol, acetaldehyde is used for replacing formaldehyde, and the yield reaches 78.8%. MSI-MS 251.4[ M + H]+。
5B 2,2' - ((ethane-1, 1-diylbis (4, 6-dimethyl-2, 1-phenylene)) bis (oxy)) diacetic amide
Referring to the IVA synthesis method, the yield is 95.6%. MSI-MS 385.5[ M + H]+。
5C 6,6' - (ethane-1, 1-diyl) bis (2, 4-dimethylaniline)
Referring to the VA synthesis method, the yield reaches 94.7%. MSI-MS 269.4[ M + H]+。
I-56, 6' - (ethane-1, 1-diyl) bis (1-isocyanato-2, 4-dimethylbenzene)
Referring to the synthesis method of I-1, the yield reaches 92.8 percent. MSI-MS 321.4[ M + H]+。
Example 6:
6A 6,6' - (ethane-1, 1-diyl) bis (2-methoxy-4-methylphenol)
Referring to the IIIA synthesis method, 4-methyl-2-methoxyphenol is used to replace 4-methylThe phenol and the acetaldehyde replace formaldehyde, and the yield reaches 77.3 percent. MSI-MS 303.4[ M + H]+。
6B 2,2' - ((ethane-1, 1-diylbis (6-methoxy-4-methyl-2, 1-phenylene)) bis (oxy)) diacetic amide
Referring to the IVA synthesis method, the yield is 92.7%. MSI-MS 417.5[ M + H]+。
6C 6,6' - (ethane-1, 1-diyl) bis (2-methoxy-4-methylaniline)
Referring to the VA synthesis method, the yield reaches 93.5 percent. MSI-MS 301.4[ M + H ]]+。
I-66, 6' - (ethane-1, 1-diyl) bis (1-isocyanato-2-methoxy-4-methylbenzene)
Referring to the synthesis method of I-1, the yield reaches 93.7%. MSI-MS 353.4[ M + H]+。
Example 7:
8A 6,6' - (propane-2, 2-diyl) bis (2, 4-dimethylphenol)
Referring to the IIIA synthesis method, 2, 4-dimethylphenol is used for replacing 4-methylphenol, acetone is used for replacing formaldehyde, and the yield reaches 76.8%. MSI-MS 285.4[ M + H]+。
8B 2,2' - ((propane-2, 2-diylbis (4, 6-dimethyl-2, 1-phenylene)) bis (oxy)) diacetic acid amide
Referring to the IVA synthesis method, the yield is 94.4%. MSI-MS 399.5[ M + H]+。
8C 6,6' - (propane-2, 2-diyl) bis (2, 4-dimethylaniline)
Referring to the VA synthesis method, the yield reaches 95.3 percent. MSI-MS 283.4[ M + H]+。
I-86, 6' - (propane-2, 2-diyl) bis (1-isocyanato-2, 4-dimethylbenzene)
Referring to the synthesis method of I-1, the yield reaches 91.5%. MSI-MS 335.4[ M + H]+。
Example 8:
1IIIA 6,6' -methylenebis (4-ethyl-2-methylphenol)
Referring to the IIIA synthesis method, 2-methyl-4-ethylphenol is used instead of 4-methylphenol, and the yield reaches 74.9%. MSI-MS 285.4[ M + H]+。
1IVA 2,2' - ((methylenebis (4-ethyl-6-methyl-2, 1-phenylene)) bis (oxy)) diacetamide
Referring to the IVA synthesis method, the yield is 93.7%. MSI-MS 399.5[ M + H]+。
1VA 6,6' -methylenebis (4-ethyl-2-methylaniline)
Referring to the VA synthesis method, the yield reaches 92.8 percent. MSI-MS 283.4[ M + H]+。
I-11 bis (5-ethyl-2-isocyanato-3-methylphenyl) methane
Referring to the synthesis method of I-1, the yield reaches 93.4 percent. MSI-MS 335.4[ M + H]+。
Example 9:
20A 6,6' -methylenebis (4-propyl-2-methylphenol)
Referring to the IIIA synthesis method, 2-methyl-4-propyl phenol was used instead of 4-methyl phenol, and the yield was 79.6%. MSI-MS 313.4[ M + H ]]+。
20B 2,2' - ((methylenebis (4-propyl-6-methyl-2, 1-phenylene)) bis (oxy)) diacetic amide
Referring to the IVA synthesis method, the yield reaches 94.8%. MSI-MS 427.5[ M + H ]]+。
20C 6,6' -methylenebis (4-propyl-2-methylaniline)
Referring to the VA synthesis method, the yield reaches 95.3 percent. MSI-MS 311.4[ M + H ]]+。
I-20 bis (2-isocyanato-3-methyl-5-propylphenyl) methane
Referring to the synthesis method of I-1, the yield reaches 93.9 percent. MSI-MS 363.4[ M + H ]]+。
Examples 10 to 12:
accurately weighing the monolignol Compound II (R)1And R2Methoxy and propyl, respectively) and formaldehyde in a 2: 1.2 separately adding a certain amount of p-toluenesulfonic acid and 98% of H into a round-bottom flask2SO4And 5M HCl, wherein the mass ratio of the compound II to the acid catalyst is 2: heating in water bath at 1, 60 deg.C, stirring vigorously for 30min, extracting the reaction solution with ethyl acetate and water, and concentrating the organic phase to obtain compound III (R)3And R4Both hydrogen) crude product whose nuclear magnetic and mass spectra are shown in fig. 3 and fig. 4. Sampling, conversion and selectivity are shown in table 2.
TABLE 2 Selectivity and conversion for examples 10-12
Examples
Catalyst and process for preparing same
Conversion rate
Selectivity is
10
98％H2SO4
89.7％
94.4％
11
5M HCl
82.1％
95.6％
12
P-toluenesulfonic acid
98.5％
98.2％
Examples 12 to 14:
accurately weighing the monolignol Compound II (R)1And R2Methoxy and propyl, respectively) and formaldehyde in a 2: 1.2, adding a certain amount of p-toluenesulfonic acid into a round-bottom flask, wherein the mass ratio of the compound II to the p-toluenesulfonic acid is 2: 1, heating in water bath at 40 deg.C, 60 deg.C and 80 deg.C respectively, stirring vigorously for about 30 minutes, and sampling after reaction (compound III, R)3And R4Both hydrogen) were detected and the conversion and selectivity are shown in table 3.
TABLE 3 Selectivity and conversion of examples 12-14
Examples
Reaction temperature
Conversion rate
Selectivity is
12
60℃
98.5％
98.2％
13
40℃
87.5％
92.6％
14
80℃
93.1％
89.6％
Examples 15 to 18:
to compound III (R)1And R2Are respectively methoxy and propyl, R3And R4All hydrogen) is added into the crude product, and a certain amount of chloroacetamide, anhydrous potassium carbonate and potassium iodide are added, wherein the molar ratio of chloroacetamide, anhydrous potassium carbonate and potassium iodide to the raw material lignin monomer compound II in the previous step is 1.25: 2.25: 0.1: 1, respectively adding a certain volume of acetone, ethanol, acetonitrile and N, N-dimethylformamide, wherein the molar volume ratio of chloroacetamide to solvent is 1.25 mol: stirring for 6h at 60 deg.C for 30L, filtering after reaction, washing residue with water to neutral, oven drying, and weighing to obtain compound IV with nuclear magnetism shown in FIG. 5 and FIG. 6. The conversion is shown in table 4.
TABLE 4 conversion of examples 15-18
Examples
Solvent(s)
Conversion rate
15
Acetone (II)
99.5％
16
Ethanol
77.2％
17
Acetonitrile
83.7％
18
N, N-dimethylformamide
86.4％
Examples 19 to 22:
to compound IV (R)1And R2Are respectively methoxy and propyl, R3And R4All are hydrogen), adding a certain amount of potassium hydroxide, sodium hydroxide, potassium tert-butoxide and potassium carbonate respectively, wherein the molar ratio of the compound IV to the base catalyst is 1: 2, according to a volume ratio of 3: 1 adding dimethyl sulfoxide (DMSO) and N, N-dimethyl propylene urea (DMPU), wherein the molar volume ratio of the compound IV to the solvent is 1 mol: 20mL of the compound was reacted at 180 ℃ for 2 hours under microwave, and after completion of the reaction, the reaction mixture was filtered, and the filtrate was extracted with ethyl acetate and water, and the ethyl acetate was removed by rotary evaporation, followed by lyophilization to obtain Compound V, wherein the nuclear magnetism thereof is shown in FIGS. 7 and 8. Sampling, conversion and selectivity are shown in table 5.
TABLE 5 Selectivity and conversion of examples 19-22
Examples
Catalyst and process for preparing same
Conversion rate
Selectivity is
19
Sodium hydroxide
90.5％
93.5％
20
Potassium tert-butoxide
56.8％
78.8％
21
Potassium carbonate
20.3％
91.5％
22
Potassium hydroxide
97.3％
98.2％
Examples 22 to 25:
adding a certain amount of potassium hydroxide into a compound IV, wherein the molar ratio of the compound IV to the potassium hydroxide is 1: 2, according to a volume ratio of 3: 1 adding dimethyl sulfoxide (DMSO) and N, N-dimethyl propylene urea (DMPU), wherein the molar volume ratio of the compound IV to the solvent is 1 mol: 20mL respectively under the microwave of 120-180 ℃ for 2 hours, after the reaction is finished, filtering, extracting the filtrate by using ethyl acetate and water, removing the ethyl acetate by rotary evaporation, freeze-drying, sampling and detecting, and the conversion rate and the selectivity are shown in Table 6.
TABLE 6 Selectivity and conversion for examples 22-25
Examples
Reaction temperature
Heating mode
Conversion rate
Selectivity is
22
180℃
Microwave oven
97.3％
98.2％
23
120℃
Microwave oven
54.3％
90.6％
24
160℃
Microwave oven
83.2％
89.6％
25
180℃
Oil bath pan
45.2％
87.6％
Examples 26 to 30:
after a spherical condenser tube, a thermometer and a nitrogen guide tube are connected to a 500mL four-mouth reaction bottle, a certain amount of compound V and solvent chlorobenzene are added, the molar volume ratio of the compound V to the chlorobenzene is 1mmol/20mL, and the mixture is stirred until the compound V and the chlorobenzene are completely dissolved. Introducing dry hydrogen chloride gas for 3h, dropwise adding a metered chlorobenzene solution of triphosgene (BTC) into a reaction bottle within 1h, and continuously stirring, wherein the molar ratio of the compound V to the BTC is 1: 1, the molar volume ratio of BTC to chlorobenzene is 1 mmol: heating 20mL to 110-. After the reaction is finished, cooling to room temperature, continuously introducing nitrogen for 30min, filtering to remove filter residues, distilling under reduced pressure to remove the solvent to obtain a lignin-based MDI product (compound I21), sampling and detecting, wherein the conversion rate is shown in Table 7. MSI-MS 395.5[ M + H]+。1H NMR(400MHz,DMSO)δ＝6.80(s,2H),6.79(s,2H),4.46(s,2H),4.02(s,6H),2.57–2.62(m,4H),1.64(dq,J＝14.8,7.3,4H),0.94(t,J＝7.3,6H).13C NMR(75MHz,DMSO)δ＝155.91,140.67,140.12,127.76,122.62,116.45,110.84,55.89,38.81,32.74,24.12,13.70.
TABLE 7 conversion of examples 26-30
Examples
Compound V/BTC
Temperature/. degree.C
Yield/%)
26
1：1
130
81.54
27
1.25：1
130
97.65
28
1.5：1
130
80.10
29
1.25：1
110
65.78
30
1.25：1
125
78.10
Examples 31-35, comparative example 1:
the polypropylene glycol N220, the lignin-based MDI (compound I21 or compound I2 or compound I8 or compound I11 or compound I20) or MDI after 3h vacuum dehydration treatment at 120 ℃ respectively are reacted according to the formula N (-NCO) under the protection of dry nitrogen gas: n (-OH) ═ 1.2: 1, adding the materials into a three-neck flask in sequence according to a metering ratio, uniformly mixing, heating to 75 ℃ for reaction for 2.5 hours, cooling to 70 ℃, adding a certain amount of dimethylolpropionic acid (DMPA) for continuous reaction for 1 hour, wherein n (DMPA): n (-NCO) ═ 4%, then as n (chain extender): adding chain extenders 1, 4-butanediol (1,4-BDO) and stannous octoate (T-9) in a metering ratio of n (-OH) to 0.17, wherein the molar ratio of the 1, 4-butanediol to the stannous octoate is 1: 0.05, reacting for 1h at 65 ℃, cooling to below 40 ℃, and transferring the mixture into a dispersion kettle. Adding Triethylamine (TEA) for neutralization to reach a neutralization degree of 120%, stirring for 4-6min, adding distilled water for emulsification for 20min, and removing the solvent by reduced pressure distillation to obtain the waterborne polyurethane emulsion.
Preparing a water-based polyurethane emulsion by replacing MDI with the obtained lignin-based MDI, and testing the particle size of the polyurethane emulsion; cutting the dried waterborne polyurethane coating film into a dumbbell shape according to QB/T2415-1998, and testing the mechanical property of the material; testing the heat resistance and crystallinity of the waterborne polyurethane adhesive film by respectively adopting a DSC tester and a TGA thermogravimetric analyzer; soaking a water-based polyurethane emulsion adhesive film sample (3cm multiplied by 3cm) in water for 24h at room temperature, taking out, absorbing water on the surface of the adhesive film by using absorbent paper, weighing the mass of the wet film, and calculating the water absorption of the adhesive film, wherein the data are shown in Table 8.
TABLE 8 analysis of water absorption, particle size, stability, thermal and mechanical properties of examples 31-35
Note: a represents the glass transition temperature, and b represents the temperature at which the sample mass loss is 60%.
The invention provides a lignin-based MDI and a preparation method and an application thereof, and a plurality of methods and ways for realizing the technical scheme, the above description is only a preferred embodiment of the invention, and it should be noted that, for a person skilled in the art, a plurality of improvements and decorations can be made without departing from the principle of the invention, and the improvements and decorations should also be regarded as the protection scope of the invention. All the components not specified in the present embodiment can be realized by the prior art.
- 上一篇：一种医用注射器针头装配设备
- 下一篇：沙格列汀中间体的合成方法