CN102617823A - Process for preparing hydroxyl polyhedral oligomeric silsesquioxane modified polyurethane - Google Patents

Abstract

The invention discloses a preparation method of cage-type silsesquioxane-modified polyurethane. Firstly, under the conditions of catalyst presence and nitrogen atmosphere protection, diisocyanate and polyether diol are reacted to prepare a prepolymer, and then 1 , 4-butanediol and hydroxycage silsesquioxane fully reacted as chain extenders, and through chemical bonding modification, a modified polyurethane with excellent film-forming and heat resistance was prepared, which improved the wear resistance of traditional polyurethane Defects of poor performance and heat resistance. When the content of hydroxycage silsesquioxane increased from 0 to 10%, the glass transition temperature of the modified polyurethane increased from -33.5°C to -28.8°C, an increase of 4.7°C, and the melting temperature also increased from 44.3°C To 54.5°C, an increase of 10.2°C, and the thermal decomposition temperature of modified polyurethane also increased by 35.3°C and 11.9°C, respectively.

Description

A kind of preparation method of hydroxyl cage type silsesquioxane modified polyurethane

technical field

The invention belongs to the technical field of polyurethane preparation technology, and in particular relates to a preparation method of hydroxyl cage silsesquioxane modified polyurethane. the

Background technique

Taiwan, China "Materials Chemistry and Physics" (Materials Chemistry and Physics, 2009, 117 (1), 91-98 pages) introduced a kind of trans-cyclohexyl-diisobutyl hydroxycage silsesquioxane through Sol-gel technology is used to synthesize polyurethane/hydroxycage silsesquioxane hybrid coatings, and it is proved that hydroxycage silsesquioxane is uniformly dispersed in the polyurethane network through scanning electron microscopy and atomic mechanical microscopy. The successful reaction between the silanol bond of hydroxyl cage silsesquioxane and polyurethane resin was verified by volume gel chromatography, Fourier transform infrared and X-ray crystal diffraction analysis. However, this method does not significantly improve the thermal stability of polyurethane. the

According to China's "Rubber Industry" magazine (2011, 58: 404-409), polyurethane was modified by cage silsesquioxane, and the research on the performance of modified polyurethane proved that although octavinyl cage Type silsesquioxane has a good reinforcing and toughening effect on polyurethane, but the reinforcing effect of octaphenyl cage silsesquioxane on polyurethane is not obvious. Silsesquioxanes physically fill the structure of polyurethane with limited improvement in thermal stability. the

Contents of the invention

The purpose of this invention is to propose a kind of preparation method of hydroxycage type silsesquioxane modified polyurethane, to overcome the above-mentioned deficiency of prior art, make prepared hydroxycage type silsesquioxane modified polyurethane have good properties Film-forming properties, while significantly improving the thermal stability and water resistance of polyurethane film materials. the

The preparation method of hydroxycage silsesquioxane modified polyurethane of the present invention is characterized in that: first dissolving diisocyanate and polyether polyol in a solvent with a molar ratio of 2:1 to form diisocyanate and polyol The total mass/volume ratio concentration of ether polyol is 0.1-1.0g/mL solution, then put it in the reactor under the protection of nitrogen atmosphere, add diisocyanate and poly The catalyst dibutyltin dilaurate or stannous octoate with a total mass of ether polyol solution of 1‰, reacted to obtain a prepolymer; : (40～10) are dissolved together in the same solvent as above to form a solution whose total mass/volume ratio concentration is 0.05g/mL, and continue to add the solution dropwise to the aforementioned reaction system containing the prepolymer under stirring Until the molar ratio of the total NCO groups to OH groups is (1.3-1.0): 1, continue to react at 50-70°C for 1.5h-3h, then pour the reaction solution into a mold coated with a release agent In the process, the film is formed in an oven at a temperature of 80-120°C for 24-48 hours to obtain a polyurethane film modified by hydroxyl cage silsesquioxane;

The solvent is tetrahydrofuran, N,N-dimethylformamide or acetone. the

Described diisocyanate is selected from toluene-2,4-diisocyanate, toluene-2,6-diisocyanate or 4,4'-diphenylmethane diisocyanate;

The polyether polyol is selected from polyethylene glycol with a molecular weight of 1000 to 10000;

The hydroxy cage silsesquioxane is selected from dihydroxy-heptaphenyl cage silsesquioxane or trihydroxy-heptaisooctyl cage silsesquioxane;

The template in the mold can be selected from glass plate, steel plate or polytetrafluoroethylene plate. the

The synthetic route of the preparation method of the above-mentioned hydroxyl cage type silsesquioxane modified polyurethane of the present invention can be expressed as follows:

In essence, the present invention is to react diisocyanate and polyester diol to prepare prepolymer under the conditions of catalyst existence and nitrogen atmosphere protection, and then add 1,4-butanediol and hydroxy cage silsesquioxane as The chain extender fully reacts, thereby preparing a modified polyurethane with excellent film-forming properties and heat resistance. Since the present invention uses a certain proportion of hydroxycage silsesquioxane as a chain extender, and hydroxycage silsesquioxane is an organic-inorganic nanocomposite material, which has a hydroxyl functional group similar to dibasic alcohols, so through chemical bonding Modified polyurethanes with excellent film-forming properties and heat resistance were prepared by modification: as the content of hydroxyl cage silsesquioxane increased from 0 to 10%, the glass transition temperature of the modified polyurethanes obtained increased from -33.5 to ℃ increased to -28.8°C, an increase of 4.7°C, and the melting temperature also increased from 44.3°C to 54.5°C, an increase of 10.2°C; the thermal decomposition temperatures increased by 35.3°C and 11.9°C, respectively. the

Description of drawings

Figure 1 is the proton magnetic spectrum of hydroxycage silsesquioxane. the

Figure 2 is the Fourier transform infrared spectrum of hydroxycage silsesquioxane (a), pure polyurethane (b) and polyurethane/hydroxycage silsesquioxane (c). the

Figure 3 is the differential scanning calorimetry curves of polyurethanes modified with different hydroxyl cage silsesquioxane contents. the

Figure 4 is the thermogravimetric analysis curves of modified polyurethanes with different hydroxyl cage silsesquioxane contents. the

Detailed ways

Example 1:

First, dissolve 1.0682g of toluene-2,4-diisocyanate and 12.0000g of polyethylene glycol with a molecular weight of 4000 in 30mL of anhydrous tetrahydrofuran, place them in a reactor under the protection of a nitrogen atmosphere, and drop them under stirring at a temperature of 60°C. Add 0.0035g dibutyltin dilaurate, and react until prepolymer is obtained; then continue to dropwise add 0.1376g dihydroxyl-heptaphenyl cage silsesquioxane (2.5% by mole fraction) and 0.1690g 1 A solution prepared by dissolving 4-butanediol in 6 mL of anhydrous tetrahydrofuran until the molar ratio of the total NCO groups and OH groups in the reaction system is 1.2:1, and then continue to react at 60 ° C for 3 h, the The reaction solution was poured into a glass mold uniformly coated with a vegetable oil release agent, and formed into a film in an oven at 80° C. for 48 hours to obtain a polyurethane film modified by hydroxyl cage silsesquioxane. the

In order to compare the advantages of the hydroxycage silsesquioxane modified polyurethane film prepared by the method of the present invention compared with the unmodified polyurethane film, the unmodified polyurethane film was first prepared: 0.1802g 1 , 4-butanediol was dissolved in 6mL of anhydrous tetrahydrofuran, and it was added dropwise to another part of the reaction system that was also reacted to the above-mentioned prepolymer under stirring until the total NCO groups in the reaction system were equal to The molar ratio of OH groups is 1.2:1, react at 60°C for 3h, pour the reaction solution into a glass mold evenly coated with vegetable oil release agent, and form a film in an oven at 80°C for 48h to obtain an unmodified polyurethane film . the

Figure 1 is the proton magnetic spectrum of hydroxycage silsesquioxane. Analysis of the proton magnetic spectrum in Figure 1 shows that the hydrogen proton peak position of the hydroxyl cage silsesquioxane is as follows: δ=8.33-6.33 ( Ph SiO ₃ ), 3.45 (N(CH ₂ CH ₂ OH) ₂ ), 2.49 (N( CH2CH2OH ) ₂ and _{SiCH2CH2CH2N ) )} , 1.73 _{( SiCH2CH2CH2N} ) _{, 1.37 (} N ( _CH2CH2OH ) _{2 )} , 0.56 ₍ SiCH2CH2CH2N _{) .}

Figure 2 is the Fourier transform infrared spectrum of hydroxycage silsesquioxane (a), pure polyurethane (b) and polyurethane/hydroxycage silsesquioxane (c). From the hydroxyl cage silsesquioxane curve a in Figure 2, it can be clearly seen that the characteristic stretching vibration broad peak of Si-O-Si appears at 1110-1132cm ^-1 and the methylene at 2890cm ^-1 The vibration peak is mainly due to the introduction of 4 methylene groups in diethanolamine. It can be clearly seen from the pure polyurethane curve b: 1092cm ^-1 is the stretching vibration peak of COC, 1467cm ^-1 is the characteristic absorption peak on the benzene ring, and 1721cm ^-1 corresponds to NH-C=O (carbon amine bond) The characteristic absorption peak of N=C=O (isocyanate) at 2275cm ^-1 is the characteristic absorption peak of the terminal group, and the characteristic absorption peak of methylene CH on the polyethylene glycol 4000 segment is corresponding to 2890cm ^-1 _. In the polyurethane/hydroxycage silsesquioxane curve c, in addition to the corresponding characteristic absorption peaks corresponding to 1467cm ^-1 , 1721cm ^-1 , 2275cm ^-1 , and 2890cm ^-1 , this is mainly due to the introduction of The bond of Si-O-Si in POSS leads to the asymmetric stretching characteristic peak at 1114cm ^-1 formed by the combination of Si-O-Si and COC in the polyurethane structure.

Example 2:

First, dissolve 1.0682g of toluene-2,4-diisocyanate and 12.0000g of polyethylene glycol with a molecular weight of 4000 in 30mL of anhydrous tetrahydrofuran, place them in a reactor under the protection of a nitrogen atmosphere, and add them dropwise at a temperature of 60°C under stirring. 0.0035g dibutyl tin dilaurate, react to obtain prepolymer; Continue to add dropwise under stirring by 0.2752g dihydroxy-heptaphenyl cage silsesquioxane (5.0% mole fraction) and 0.1577g 1, A solution prepared by dissolving 4-butanediol in 6 mL of anhydrous tetrahydrofuran until the molar ratio of the total NCO groups and OH groups in the reaction system is 1.2:1, and then continue to react at 60 ° C for 3 h, the reaction Pour the solution into a glass mold evenly coated with vegetable oil release agent, and form a film in an oven at 80°C for 48 hours to obtain a polyurethane film modified by hydroxyl cage silsesquioxane. the

Example 3:

First, dissolve 1.0682g of toluene-2,4-diisocyanate and 12.0000g of polyethylene glycol with a molecular weight of 4000 in 30mL of anhydrous tetrahydrofuran, place them in a reactor under the protection of a nitrogen atmosphere, and drop them under stirring at a temperature of 60°C. Add 0.0035g dibutyltin dilaurate, and react until prepolymer is obtained; Continue to add dropwise under stirring by 0.4129g dihydroxy-heptaphenyl cage silsesquioxane (mole fraction 7.5%) and 0.1465g 1 A solution prepared by dissolving 4-butanediol in 6 mL of anhydrous tetrahydrofuran until the molar ratio of the total NCO groups and OH groups in the reaction system is 1.2:1, and then continue to react at 60 ° C for 3 h, the The reaction solution was poured into a glass mold uniformly coated with a vegetable oil release agent, and formed into a film in an oven at 80° C. for 48 hours to obtain a polyurethane film modified by hydroxyl cage silsesquioxane. the

Example 4:

First, dissolve 1.0682g of toluene-2,4-diisocyanate and 12.0000g of polyethylene glycol with a molecular weight of 4000 in 30mL of anhydrous tetrahydrofuran, place them in a reactor under the protection of a nitrogen atmosphere, and drop them under stirring at a temperature of 60°C. Add 0.0035g dibutyltin dilaurate, and react until prepolymer is obtained; then continue to dropwise add 0.5505g dihydroxy-heptaphenyl cage silsesquioxane (mole fraction 10.0%) and 0.1352g 1 A solution prepared by dissolving 4-butanediol in 6 mL of anhydrous tetrahydrofuran until the molar ratio of the total NCO groups and OH groups in the reaction system is 1.2:1, and then continue to react at 60 ° C for 3 h, the The reaction solution was poured into a glass mold uniformly coated with a vegetable oil release agent, and formed into a film in an oven at 80° C. for 48 hours to obtain a polyurethane film modified by hydroxyl cage silsesquioxane. the

Figure 3 is the differential scanning calorimetry curves of polyurethanes modified with different hydroxyl cage silsesquioxane contents. By analyzing the differential scanning calorimetry curve in Figure 3, it can be seen that as the content of hydroxycage silsesquioxane increases from 0 to 10%, the position of the measured differential scanning calorimetry curve is gradually changing, that is Curve d in Fig. 3 gradually shifts into curve e, curve f, curve g and finally becomes curve h successively, thus it can be seen that: along with the content of hydroxycage silsesquioxane increasing from 0 to 10%, the obtained The glass transition temperature of the modified polyurethane increased from -33.5°C to -28.8°C, an increase of 4.7°C; the melting temperature also increased from 44.3°C to 54.5°C, an increase of 10.2°C. the

Figure 4 is the thermogravimetric analysis curves of modified polyurethanes with different hydroxyl cage silsesquioxane contents. By analyzing the thermogravimetric analysis curve in Fig. 4, it can be seen that along with the content of hydroxycage silsesquioxane increasing from 0 to 10%, the position of the thermogravimetric analysis curve measured is gradually changing, that is, as shown in Fig. 4 Curve i in turn gradually shifted to curve m, curve n, and curve o and finally turned into curve p. It can be seen from this that as the content of hydroxycage silsesquioxane increases from 0 to 10%, the obtained modified The thermal decomposition temperature of polyurethane increased by 35.3℃ and 11.9℃ respectively. the

It can be seen that the introduction of hydroxyl cage silsesquioxane has significantly improved the thermal stability of the synthesized polyurethane. The main reason is that the introduction of nano-scale hydroxyl cage silsesquioxane into the polyurethane network structure chain improves the chemical bonding in a certain area, thereby improving the thermal stability of the synthesized polyurethane. the

Embodiment 5:

Dissolve 1.5014g of p-tolyl diisocyanate and 3.0000g of polyethylene glycol with a molecular weight of 1000 in 30mL of anhydrous N,N-dimethylformamide, and put them in a reactor under nitrogen atmosphere protection at 50°C Add dropwise 0.0035g stannous octoate under temperature and stirring, react to obtain prepolymer; Continue to add dropwise under stirring by 0.1376g dihydroxyl-heptaphenyl cage silsesquioxane (2.5% by mole fraction) and 0.1690 The solution prepared by dissolving g 1,4-butanediol in 6 mL of anhydrous N, N-dimethylformamide until the molar ratio of the total NCO groups and OH groups in the reaction system is 1.2:1, and then Continue to react at 50°C for 2h, pour the reaction solution into a glass mold evenly coated with vegetable oil release agent, and form a film in an oven at 90°C for 42h to obtain a polyurethane film modified with hydroxyl cage silsesquioxane. the

Embodiment 6:

Dissolve 1.5014g of p-tolyl diisocyanate and 6.0000g of polyethylene glycol with a molecular weight of 2000 in 30mL of anhydrous N,N-dimethylformamide, place them in a reactor protected by a nitrogen atmosphere, and heat at 70°C Add dropwise 0.0035g stannous octoate under temperature and stirring, react to obtain prepolymer; Continue to add dropwise under stirring by 0.1376g dihydroxyl-heptaphenyl cage silsesquioxane (2.5% by mole fraction) and 0.1690 The solution prepared by dissolving g 1,4-butanediol in 6 mL of anhydrous N, N-dimethylformamide until the molar ratio of the total NCO groups and OH groups in the reaction system is 1.2:1, and then Continue to react at 70°C for 2h, pour the reaction solution into a glass mold evenly coated with vegetable oil release agent, and form a film in an oven at 100°C for 36h to obtain a polyurethane film modified by hydroxyl cage silsesquioxane. the

Embodiment 7:

First, 1.0682g of toluene-2,6-diisocyanate and 18.0000g of polyethylene glycol with a molecular weight of 6000 were dissolved in 30mL of anhydrous N,N-dimethylformamide, and placed in a reactor protected by a nitrogen atmosphere. Add 0.0035g of stannous octoate dropwise under stirring at 70°C to react until a prepolymer is obtained; then continue to dropwise add 0.0985g of trihydroxy-heptaisooctyl cage silsesquioxane (mole fraction 2.5 %) and 0.1690g of 1,4-butanediol dissolved in 6mL of anhydrous N, the solution prepared in N-dimethylformamide, until the molar ratio of total NCO groups and OH groups in the reaction system is 1.2 : 1, continue to react at 70°C for 1.5h, pour the reaction solution into a glass mold evenly coated with vegetable oil release agent, and form a film in an oven at 110°C for 30h to obtain modified hydroxycage silsesquioxane permanent polyurethane membrane. the

Embodiment 8:

First, dissolve 1.0682g of toluene-2,6-diisocyanate and 18.0000g of polyethylene glycol with a molecular weight of 6000 in 30mL of anhydrous acetone, place them in a reactor protected by a nitrogen atmosphere, and drop them under stirring at a temperature of 70°C. Add 0.0035g stannous octoate, and react until prepolymer is obtained; then continue to dropwise add 0.0985g trihydroxy-heptaisooctyl cage silsesquioxane (mole fraction 2.5%) and 0.1690g 1,4 -The solution prepared by dissolving butanediol in 6mL of anhydrous acetone until the molar ratio of the total NCO groups and OH groups in the reaction system is 1.2:1, then continue to react at 70°C for 1.5h, and the reaction Pour the solution into a glass mold evenly coated with vegetable oil release agent, and form a film in an oven at 120°C for 24 hours to obtain a polyurethane film modified by hydroxyl cage silsesquioxane. the

Embodiment 9:

First, dissolve 1.0682g of toluene-2,6-diisocyanate and 30.0000g of polyethylene glycol with a molecular weight of 10,000 in 30mL of anhydrous acetone, place them in a reactor protected by a nitrogen atmosphere, and drop them under stirring at a temperature of 70°C. Add 0.0035g stannous octoate, and react until prepolymer is obtained; continue to dropwise add 0.5505g dihydroxy-heptaphenyl cage silsesquioxane (mole fraction 10.0%) and 0.1352g 1,4- A solution prepared by dissolving butanediol in 6 mL of anhydrous acetone until the molar ratio of the total NCO groups and OH groups in the reaction system is 1.2:1, and then continue to react at a temperature of 70 ° C for 1.5 h, the reaction solution Pour it into a glass mold evenly coated with a vegetable oil release agent, and form a film in an oven at 120°C for 24 hours to obtain a polyurethane film modified with hydroxy cage silsesquioxane. the

In the nine examples mentioned above, the molar ratio of the total NCO groups to OH groups in the reaction system is 1.2:1. And when the molar ratio of NCO group and OH group is 1.3:1 to 1.0:1, the same product as in the above examples can also be obtained. The detection methods and results of the products obtained in the above examples are also basically the same as those in Example 1, so no further details are given. the

In essence, the present invention firstly reacts diisocyanate and polyether diol to prepare a prepolymer under the condition that the catalyst is protected by a nitrogen atmosphere, and then adds 1,4-butanediol and hydroxyl cage silsesquioxane as the expansion agent. The chain agent is fully reacted, thereby preparing a modified polyurethane with excellent film-forming properties and heat resistance. Because the present invention adopts a certain proportion of hydroxycage silsesquioxane as a chain extender, hydroxycage silsesquioxane is an organic-inorganic nanocomposite material, which has a hydroxyl functional group similar to dibasic alcohols, so it is modified by chemical bonding. A modified polyurethane with excellent film-forming properties and heat resistance was successfully prepared: as the content of hydroxyl cage silsesquioxane increased from 0 to 10%, the glass transition temperature of the obtained modified polyurethane increased from -33.5°C to It increased to -28.8°C, an increase of 4.7°C, and the melting temperature also increased from 44.3°C to 54.5°C, an increase of 10.2°C; its thermal decomposition temperature increased by 35.3°C and 11.9°C, respectively. the

Claims (5)

1. a kind of preparation method of hydroxyl cage type silsesquioxane modified polyurethane, it is characterized in that: first diisocyanate and polyether polyol are dissolved in the solvent together in the ratio of 2: 1 with molar ratio and are made into diisocyanate and polyether polyols with a total mass/volume concentration of 0.1 to 1.0 g/mL solution, and then place it in a reactor protected by a nitrogen atmosphere, and add diisocyanate dropwise at a temperature of 50 to 70°C under stirring and the catalyst dibutyltin dilaurate or stannous octoate with a total mass of polyether polyol solution of 1‰ to react to obtain a prepolymer; Ratio 1: (40～10) was dissolved in the same solvent as above to form a solution with a total mass/volume ratio concentration of 0.05g/mL, and the solution was added dropwise to the above-mentioned reaction containing prepolymer under stirring. In the system until the molar ratio of the total NCO groups to OH groups is (1.3-1.0): 1, and then continue to react at a temperature of 50-70°C for 1.5h-3h, pour the reaction solution into the mold release agent In the mold, the film is formed in an oven at a temperature of 80-120 ° C for 24 to 48 hours to obtain a polyurethane film modified by hydroxyl cage silsesquioxane; the solvent is tetrahydrofuran, N, N-dimethylformamide or acetone. 2. the preparation method of hydroxy cage type silsesquioxane modified polyurethane as claimed in claim 1 is characterized in that described diisocyanate is selected from toluene-2,4-diisocyanate, toluene-2,6-diisocyanate or 4 , 4'-Diphenylmethane diisocyanate. 3. The preparation method of hydroxycage silsesquioxane modified polyurethane as claimed in claim 1, characterized in that said polyether polyol is selected from polyethylene glycol with a molecular weight of 1000-10000. 4. the preparation method of hydroxy cage silsesquioxane modified polyurethane as claimed in claim 1 is characterized in that said hydroxy cage silsesquioxane is selected from dihydroxy-heptaphenyl cage silsesquioxane Or trihydroxy-heptaisooctyl cage silsesquioxane. 5. The preparation method of hydroxycage silsesquioxane modified polyurethane as claimed in claim 1, characterized in that the template in the mold is selected from glass plate, steel plate or polytetrafluoroethylene plate.

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