Detailed description of the preferred embodiments
The present invention is further illustrated by the following examples, but the present invention is not limited by the examples. The raw materials in the invention are all conventional and commercially available.
The polyesters prepared in the examples were each characterized by 1H NMR using a Bruker Avance DMX NMR apparatus with TMS as an internal standard and CDCl 3 Is a solvent.
Molecular weight testing: intrinsic viscosity was measured with reference to GB/T1632.5-2008 at 25℃with phenol/tetrachloroethane (50/50, wt/wt) as solvent and polyester concentration of 0.5g/dL, measured with an Ubbelohde viscometer.
Mechanical property test: tensile breaking strength test is carried out according to GB/T1040.1-2006 standard; breaking strength is carried out according to GB/T31967.2-2015 standard; elongation at break is carried out according to GB/T2567-2008 standard; impact properties are carried out according to GB/T1843-2008 standard;
artificial accelerated ageing test
The accelerated ageing test was carried out in a manual accelerated ageing oven QUV-II (Kedi instrument: weathering test oven) using a wavelength peak at 313nm. According to national standard GBT-14522-2008, exposing the sample plate to ultraviolet light for 360 hours, setting the temperature of a blackboard to 50 ℃, setting the temperature of a dry bulb to 60 ℃, setting the temperature of a wet bulb to 50 ℃, and carrying out 4-hour condensation and 4-hour illumination on one cycle period.
The coating thickness was measured with reference to GB/T20220-2006.
The impact resistance of the coating is obtained by an impact instrument of a national Tianjin instrument testing machine factory;
yield = 100% x actual yield of target product/theoretical yield of target product.
Example 1:
4g of 4-hydroxybenzaldehyde and 2.218g of pentaerythritol were placed in a one-necked flask, and 20ml of DMF and 0.112g of p-toluenesulfonic acid were added. The reaction was carried out at 85℃for 3 hours, after the completion of the reaction, the reaction mixture was cooled, and the reaction mixture was added dropwise to 100ml of distilled water to precipitate a white precipitate. After the precipitation is completed, the mixture is filtered, washed by 100ml of distilled water and dried to obtain 4.231g of 4,4'- (2, 4,8, 10-tetraoxapipro [5,5] undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5,5] undecane-3, 9-diyl) diphenol). The yield was 76.9%.
4.231g (12.3 mmol) of 4,4' - (2, 4,8, 10-tetraoxapiporo [5, 5)]undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5, 5)]Undecane-3, 9-diyl) diphenol) was dissolved in 30ml DMF, 2.273g (24.6 mmol) of ethylene carbonate were added, 0.211g K was added 2 CO 3 And (3) reacting for 2 hours at 150-160 ℃ as a catalyst, cooling to room temperature after the reaction, transferring to 100ml of distilled water, precipitating white solid, filtering, collecting precipitate, washing with water for 2-3 times, and drying to obtain 4.516g of diol monomer M with the yield of 85.1%.
3.444g (20 mmol) of 1, 4-cyclohexanedicarboxylic acid, 3.024g (7.0 mmol) of diol monomer M and 1.606g (11 mmol) of isosorbide are added into a reaction vessel, 0.0021g of cerium acetate-tetrabutyl titanate is added, nitrogen is introduced for protection, stirring reaction is carried out for 4 hours at 180 ℃, the temperature is continuously increased to 240 ℃, the absolute pressure in the reaction system is controlled to be about 80 Pa, and polycondensation reaction is carried out under full stirring for 2h, thus obtaining a polycondensation crude product; dissolving the polycondensation crude product with 30ml chloroform, filtering, collecting clear liquid, adding enough methanol into clear liquid until precipitation is not increased, centrifuging, filtering, washing the obtained solid with 50ml ethanol, and drying the filtered solid at 60deg.C for 2h to obtain 7.088g copolyester CP 1 Copolyester CP 1 Molecular weight of 2.05X10 4 g/mol, yield 88.2%. For copolyester CP 1 The test results are shown in Table 1.
Collection of 100g of copolyester CP 1 Adding 34g of triglycidyl isocyanurate, 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzoin) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the spray gun voltage to be 60 kV, and spraying on a degreased substrate to obtain the ultra-resistant Hou Juzhi powder coating with the thickness of 90-100 mu m.
Super-resistant Hou Juzhi powder coatings are used for automotive hubs. Collection of 100g of copolyester CP 1 With 34g of isocyanuric acidAdding triglycidyl acid, 104g of barium sulfate, 8g of a leveling agent (GLP 588), 3.2g of Benzoin (Benzon) and 4.8g of a brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the spray gun voltage to be 60 kV, spraying on an automobile hub, and baking and thermosetting in a high-temperature oven to form a film. The results of the ultra-high Hou Juzhi powder coating test are shown in table 2.
Example 2:
4g of 4-hydroxybenzaldehyde and 2.218g of pentaerythritol were placed in a one-necked flask, and 20ml of DMF and 0.112g of p-toluenesulfonic acid were added. The reaction was carried out at 85℃for 8 hours, after the completion of the reaction, the reaction mixture was cooled, and the reaction mixture was added dropwise to 100ml of distilled water to precipitate a white precipitate. After the precipitation is complete, the mixture is filtered, washed by 100ml of distilled water and dried to obtain 4.328g of 4,4'- (2, 4,8, 10-tetraoxapipro [5,5] undecan-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5,5] undecane-3, 9-diyl) diphenol). The yield was 78.7%.
4.328g (12.6 mmol) of 4,4' - (2, 4,8, 10-tetraoxapiporo [5, 5)]undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5, 5)]Undecane-3, 9-diyl) diphenol) was dissolved in 30ml DMF, 2.218g (25.2 mmol) of ethylene carbonate were added, 0.216g K was added 2 CO 3 And (3) reacting for 2 hours at 150-160 ℃ as a catalyst, cooling to room temperature after the reaction, transferring to 100ml of distilled water, precipitating white solid, filtering, collecting precipitate, washing with water for 2-3 times, and drying to obtain 4.540g of diol monomer M with the yield of 83.4%.
3.444g (20 mmol) of 1, 4-cyclohexanedicarboxylic acid, 3.456g (8.0 mmol) of diol monomer M and 1.606g (11 mmol) of isosorbide are added into a reaction vessel, 0.0021g of cerium acetate-tetrabutyl titanate is added, nitrogen is introduced for protection, stirring reaction is carried out for 4 hours at 180 ℃, the temperature is continuously increased to 240 ℃, the absolute pressure in the reaction system is controlled to be about 80 Pa, and polycondensation reaction is carried out under full stirring for 2h, thus obtaining a polycondensation crude product; dissolving the polycondensation crude product with 30ml chloroform, filtering, collecting clear solution, adding enough methanol into the clear solution until precipitation is not increased, centrifuging, and filteringThe solid was washed with 50ml ethanol and the re-filtered solid was dried at 60℃for 2h to give 7.664g of copolyester CP 2 Copolyester CP 2 Molecular weight of 2.18×10 4 g/mol, yield 90.1%, for copolyester CP 2 The test results are shown in Table 1.
Collection of 100g of copolyester CP 2 Adding 34g of triglycidyl isocyanurate, 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzoin) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the spray gun voltage to be 60 kV, and spraying on a degreased substrate to obtain the ultra-resistant Hou Juzhi powder coating with the thickness of 90-100 mu m.
Super-resistant Hou Juzhi powder coatings are used as motorcycle topcoats. Collection of 100g of copolyester CP 2 Adding 34g of triglycidyl isocyanurate, 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzon) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the voltage of the spray gun to be 60 kV, spraying on the surface of a motorcycle body, and baking and thermally curing in a high-temperature oven to form a film. The results of the ultra-high Hou Juzhi powder coating test are shown in table 2.
Example 3:
4g of 4-hydroxybenzaldehyde and 2.218g of pentaerythritol were placed in a one-necked flask, and 20ml of DMF and 0.112g of p-toluenesulfonic acid were added. The reaction was carried out at 85℃for 8 hours, after the completion of the reaction, the reaction mixture was cooled, and the reaction mixture was added dropwise to 100ml of distilled water to precipitate a white precipitate. After the precipitation is completed, the mixture is filtered, washed by 100ml of distilled water and dried to obtain 4.4573 g of 4,4'- (2, 4,8, 10-tetraoxapiporo [5,5] undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5,5] undecane-3, 9-diyl) diphenol) with the yield of 81.0 percent.
4.453g (12.9 mmol) of 4,4' - (2, 4,8, 10-tetraoxapiporo [5, 5)]undecane-3,9-diyl)diphenol(4,4'-(2, 4,8, 10-tetraoxapyridine [5,5]]Undecane-3, 9-diyl) diphenol) was dissolved in 30ml DMF, 2.218g (25.8 mmol) of ethylene carbonate were added, 0.223g K was added 2 CO 3 As a catalyst, reacting for 2 hours at 150-160 ℃, cooling to room temperature after the reaction, transferring to 100ml of distilled water, precipitating white solid, filtering, collecting precipitate, washing with water for 2-3 times, and drying to obtain 4.631g of glycol monomer M with the yield of 83.1%.
3.444g (20 mmol) of 1, 4-cyclohexanedicarboxylic acid, 3.802g (8.8 mmol) of diol monomer M and 1.606g (11 mmol) of isosorbide are added into a reaction vessel, 0.0021g of cerium acetate-tetrabutyl titanate is added, nitrogen is introduced for protection, stirring reaction is carried out for 4 hours at 180 ℃, the temperature is continuously increased to 240 ℃, the absolute pressure in the reaction system is controlled to be about 80 Pa, and polycondensation reaction is carried out under full stirring for 2h, thus obtaining a polycondensation crude product; dissolving the polycondensation crude product with 30ml chloroform, filtering, collecting clear liquid, adding enough methanol into clear liquid until precipitation is not increased, centrifuging, filtering, washing the obtained solid with 50ml ethanol, and drying the filtered solid at 60deg.C for 2h to obtain 7.896g copolyester CP 3 Copolyester CP 3 Molecular weight of 2.36×10 4 g/mol, yield 89.2%, for copolyester CP 3 The test results are shown in Table 1.
Collection of 100g of copolyester CP 3 Adding 34g of Triglycidyl Isocyanurate (TIGC), 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzonin) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the spray gun voltage to be 60 kV, and spraying on a degreased base material to obtain the super-resistant Hou Juzhi powder coating with the thickness of 90-100 mu m.
Super-resistant Hou Juzhi powder coatings are used on paper used for important document materials in archives, museums, etc. Collection of 100g of copolyester CP 3 Adding 34g triglycidyl isocyanurate, 104g barium sulfate, 8g leveling agent (GLP 588), 3.2g Benzoin (Benzon) and 4.8g brightening agent (701B) into a premixing machine for fillingUniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving with a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the voltage of the spray gun to be 60 kV, directly adsorbing powder coating on the surface of paper under the action of an electric field, and fixing on the surface of the paper through thermo-mechanical calendaring treatment to form the ultra-resistant Hou Juzhi powder coating. The results of the ultra-high Hou Juzhi powder coating test are shown in table 2.
Example 4:
4g of 4-hydroxybenzaldehyde and 2.218g of pentaerythritol were placed in a one-necked flask, and 20ml of DMF and 0.112g of p-toluenesulfonic acid were added. The reaction was carried out at 85℃for 8 hours, after the completion of the reaction, the reaction mixture was cooled, and the reaction mixture was added dropwise to 100ml of distilled water to precipitate a white precipitate. After the precipitation is completed, the mixture is filtered, washed by 100ml of distilled water and dried to obtain 4.252g of 4,4'- (2, 4,8, 10-tetraoxapipro [5,5] undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5,5] undecane-3, 9-diyl) diphenol). The yield was 77.3%.
4.252g (12.4 mmol) of 4,4' - (2, 4,8, 10-tetraoxapiporo [5, 5)]undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5, 5)]Undecane-3, 9-diyl) diphenol) was dissolved in 30ml DMF, 2.182g (24.8 mmol) of ethylene carbonate were added, 0.213g K was added 2 CO 3 And (3) reacting for 2 hours at 150-160 ℃ as a catalyst, cooling to room temperature after the reaction, transferring to 100ml of distilled water, precipitating white solid, filtering, collecting precipitate, washing with water for 2-3 times, and drying to obtain 4.569g of diol monomer M with the yield of 85.3%.
3.444g (20 mmol) of 1, 4-cyclohexanedicarboxylic acid, 3.802g (8.8 mmol) of diol monomer M and 1.548g (10.6 mmol) of isosorbide are added into a reaction vessel, 0.0021g of cerium acetate-tetrabutyl titanate is added, nitrogen is introduced for protection, stirring reaction is carried out for 4 hours at 180 ℃, the temperature is continuously increased to 240 ℃, the absolute pressure in a reaction system is controlled to be about 80 Pa, and polycondensation reaction is carried out under full stirring for 2h, thus obtaining a polycondensation crude product; dissolving the polycondensation crude product with 30ml chloroform, filtering, collecting clear solution, adding methanol into clear solution until precipitation is not increased, centrifuging, filtering, washing the obtained solid with 50ml ethanol, and filtering again to obtain solid at 60deg.CDrying 2h to give 8.029g of copolyester CP 4 Copolyester CP 4 Molecular weight of 2.21×10 4 g/mol, yield 91.3%, for copolyester CP 4 The test results are shown in Table 1.
Collection of 100g of copolyester CP 4 Adding 34g of Triglycidyl Isocyanurate (TIGC), 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzonin) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the spray gun voltage to be 60 kV, and spraying on a degreased base material to obtain the super-resistant Hou Juzhi powder coating with the thickness of 90-100 mu m.
Super-resistant Hou Juzhi powder coatings are used for plastic surfaces. Collection of 100g of copolyester CP 4 Adding 34g of triglycidyl isocyanurate, 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzon) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the voltage of the spray gun to be 60 kV, and adsorbing the powder coating on the surface of plastic under the action of an electric field to form the super-resistant Hou Juzhi powder coating. The results of the ultra-high Hou Juzhi powder coating test are shown in table 2.
Example 5:
4g of 4-hydroxybenzaldehyde and 2.218g of pentaerythritol were placed in a one-necked flask, and 20ml of DMF and 0.112g of p-toluenesulfonic acid were added. The reaction was carried out at 85℃for 8 hours, after the completion of the reaction, the reaction mixture was cooled, and the reaction mixture was added dropwise to 100ml of distilled water to precipitate a white precipitate. After the precipitation is completed, the mixture is filtered, washed by 100ml of distilled water and dried to obtain 4.153g of 4,4'- (2, 4,8, 10-tetraoxapiporo [5,5] undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5,5] undecane-3, 9-diyl) diphenol) with the yield of 75.5 percent.
4.153g (12.1 mmol) of 4,4' - (2, 4,8, 10-tetraoxapiporo [5, 5)]undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5, 5)]Undecane-3, 9-diyl) diphenol) was dissolved in 30ml DMF, 2.130g (24.2 mmol) of ethylene carbonate were added, 0.208g K was added 2 CO 3 And (3) reacting for 2 hours at 150-160 ℃ as a catalyst, cooling to room temperature after the reaction, transferring to 100ml of distilled water, precipitating white solid, filtering, collecting precipitate, washing with water for 2-3 times, and drying to obtain 4.427g of glycol monomer M with the yield of 84.7%.
3.444g (20 mmol) of 1, 4-cyclohexanedicarboxylic acid, 3.802g (8.8 mmol) of diol monomer M and 1.664g (11.4 mmol) of isosorbide are added into a reaction vessel, 0.0021g of cerium acetate-tetrabutyl titanate is added, nitrogen is introduced for protection, stirring reaction is carried out for 4 hours at 180 ℃, the temperature is continuously increased to 240 ℃, the absolute pressure in a reaction system is controlled to be about 80 Pa, and polycondensation reaction is carried out under full stirring for 2h, thus obtaining a polycondensation crude product; dissolving the polycondensation crude product with 30ml chloroform, filtering, collecting clear liquid, adding enough methanol into clear liquid until precipitation is not increased, centrifuging, filtering, washing the obtained solid with 50ml ethanol, and drying the filtered solid at 60deg.C for 2h to obtain 7.903g copolyester CP 5 Copolyester CP 5 Molecular weight of 2.57×10 4 g/mol, yield 88.7%, for copolyester CP 5 The test results are shown in Table 1.
Collection of 100g of copolyester CP 5 Adding 34g of Triglycidyl Isocyanurate (TIGC), 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzonin) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the spray gun voltage to be 60 kV, and spraying on a degreased base material to obtain the super-resistant Hou Juzhi powder coating with the thickness of 90-100 mu m.
Super-resistant Hou Juzhi powder coatings are used on wood surfaces. Collection of 100g of copolyester CP 5 Adding 34g triglycidyl isocyanurate, 104g barium sulfate, 8g flatting agent (GLP 588), 3.2g Benzoin and 4.8g brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double screw extruder, extruding, cooling, tabletting, crushing and powderingAfter crushing, sieving with a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the voltage of the spray gun to be 60 kV, adsorbing the powder coating on the surface of wood under the action of an electric field, and infrared heating to cure the surface to form the ultra-resistant Hou Juzhi powder coating. The results of the ultra-high Hou Juzhi powder coating test are shown in table 2.
Example 6:
4g of 4-hydroxybenzaldehyde and 2.218g of pentaerythritol were placed in a one-necked flask, and 20ml of DMF and 0.112g of p-toluenesulfonic acid were added. The reaction was carried out at 85℃for 8 hours, after the completion of the reaction, the reaction mixture was cooled, and the reaction mixture was added dropwise to 100ml of distilled water to precipitate a white precipitate. After the precipitation is completed, the mixture is filtered, washed by 100ml of distilled water and dried to obtain 4.421g of 4,4'- (2, 4,8, 10-tetraoxapipro [5,5] undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5,5] undecane-3, 9-diyl) diphenol) with the yield of 80.4 percent.
4.421g (12.9 mmol) of 4,4' - (2, 4,8, 10-tetraoxapiporo [5, 5)]undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5, 5)]Undecane-3, 9-diyl) diphenol) was dissolved in 30ml DMF, 2.270g (25.8 mmol) of ethylene carbonate were added, 0.221g K was added 2 CO 3 And (3) reacting for 2 hours at 150-160 ℃ as a catalyst, cooling to room temperature after the reaction, transferring to 100ml of distilled water, precipitating white solid, filtering, collecting precipitate, washing with water for 2-3 times, and drying to obtain 4.620g of diol monomer M with the yield of 82.9%.
3.444g (20 mmol) of 1, 4-cyclohexanedicarboxylic acid, 3.802g (8.8 mmol) of diol monomer M and 1.781g (12.2 mmol) of isosorbide are added into a reaction vessel, 0.0021g of cerium acetate-tetrabutyl titanate is added, nitrogen is introduced for protection, stirring reaction is carried out for 4 hours at 180 ℃, the temperature is continuously increased to 240 ℃, the absolute pressure in a reaction system is controlled to be about 80 Pa, and polycondensation reaction is carried out for 2h under full stirring, thus obtaining a polycondensation crude product; dissolving the polycondensation crude product with 30ml chloroform, filtering, collecting clear liquid, adding enough methanol into clear liquid until precipitation is not increased, centrifuging, filtering, washing the obtained solid with 50ml ethanol, and drying the filtered solid at 60deg.C for 2h to obtain 7.935g copolyester CP 6 Copolyester CP 6 Molecular weight of 2.83×10 4 g/mol, yield87.9% for copolyester CP 6 The test results are shown in Table 1.
Collection of 100g of copolyester CP 6 Adding 34g of Triglycidyl Isocyanurate (TIGC), 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzonin) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the spray gun voltage to be 60 kV, and spraying on a degreased base material to obtain the super-resistant Hou Juzhi powder coating with the thickness of 90-100 mu m.
Super-resistant Hou Juzhi powder coatings are used on furniture surfaces. Collection of 100g of copolyester CP 6 Adding 34g of triglycidyl isocyanurate, 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzon) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the voltage of the spray gun to be 60 kV, adsorbing the powder coating on the surface of a household appliance under the action of an electric field, and forming an ultra-high Hou Juzhi powder coating on the infrared heat-cured surface. The results of the ultra-high Hou Juzhi powder coating test are shown in table 2.
Example 7:
4g of 4-hydroxybenzaldehyde and 2.218g of pentaerythritol were placed in a one-necked flask, and 20ml of DMF and 0.112g of p-toluenesulfonic acid were added. The reaction was carried out at 85℃for 8 hours, after the completion of the reaction, the reaction mixture was cooled, and the reaction mixture was added dropwise to 100ml of distilled water to precipitate a white precipitate. After the precipitation is completed, the mixture is filtered, washed by 100ml of distilled water and dried to obtain 4.208g of 4,4'- (2, 4,8, 10-tetraoxapipro [5,5] undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5,5] undecane-3, 9-diyl) diphenol) with the yield of 76.5 percent.
4.208g (12.2 mmol) of 4,4' - (2, 4,8,10-tetraoxaspiro [5, 5)]undecane-3, 9-diyl) diphenol (4, 4' - (2, 4,8, 10-tetraoxapyridine [5, 5)]Undecane-3, 9-diyl) diphenol) was dissolved in 30ml DMF, 2.147g (24.4 mmol) of ethylene carbonate were added0.210gK 2 CO 3 And (3) reacting for 2 hours at 150-160 ℃ as a catalyst, cooling to room temperature after the reaction, transferring to 100ml of distilled water, precipitating white solid, filtering, collecting precipitate, washing with water for 2-3 times, and drying to obtain 4.448g of glycol monomer M with the yield of 84.4%.
3.444g (20 mmol) of 1, 4-cyclohexanedicarboxylic acid, 3.802g (8.8 mmol) of diol monomer M and 1.781g (12.2 mmol) of isosorbide are added into a reaction vessel, 0.0021g of niobic acid is added, nitrogen is introduced for protection, stirring reaction is carried out for 4 hours at 180 ℃, heating is continued to 240 ℃, absolute pressure in a reaction system is controlled to be about 80 Pa, and polycondensation reaction is carried out under full stirring for 2h, thus obtaining a polycondensation crude product; dissolving the polycondensation crude product with 30ml chloroform, filtering, collecting clear liquid, adding enough methanol into clear liquid until precipitation is not increased, centrifuging, filtering, washing the obtained solid with 50ml ethanol, and drying the filtered solid at 60deg.C for 2h to obtain 7.709g copolyester CP 7 Copolyester CP 7 Molecular weight of 2.52×10 4 g/mol, yield of 85.4%, for copolyester CP 7 The test results are shown in Table 1.
Collection of 100g of copolyester CP 7 Adding 34g of Triglycidyl Isocyanurate (TIGC), 104g of barium sulfate, 8g of flatting agent (GLP 588), 3.2g of Benzoin (Benzonin) and 4.8g of brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving by using a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, setting the spray gun voltage to be 60 kV, and spraying on a degreased base material to obtain the super-resistant Hou Juzhi powder coating with the thickness of 90-100 mu m.
The super-resistant Hou Juzhi powder coating is used for engineering pipelines. Collection of 100g of copolyester CP 7 Adding 34g triglycidyl isocyanurate, 104g barium sulfate, 8g flatting agent (GLP 588), 3.2g Benzoin (Benzoin) and 4.8g brightening agent (701B) into a premixing machine, fully and uniformly mixing, pouring into a double-screw extruder, extruding, cooling, tabletting, crushing, sieving with a 180-mesh screen, pouring the lower layer into a spray can with a spray gun, and setting the voltage of the spray gun to 60 kAnd V, spraying the powder coating on the surface of the pipeline under the action of an electric field, and curing the surface at high temperature to form the super-resistant Hou Juzhi powder coating. The results of the ultra-high Hou Juzhi powder coating test are shown in table 2.
TABLE 1 copolyester CP in examples 1-7 1 ~CP 7 Test results of samples
[ eta 1] is the initial intrinsic viscosity of the sample, and [ eta 2] is the intrinsic viscosity of the sample after 3 years of degradation in a natural soil environment.
[3] Tang Zhuohua research on biodegradable polyester elastomer particle modified PBS [ D ]. Qingdao university of science and technology, 2019.
Table 2: powder coating test results
Project
| CP 1 | CP 2 | CP 3 | CP 4 | CP 5 | CP 6 | CP 7 |
Film thickness/. Mu.m
| 90~100
| 90~100
| 90~100
| 90~100
| 90~100
| 90~100
| 90~100
|
Gloss retention (%)
| 90
| 92
| 91
| 93
| 90
| 91
| 92
|
Impact test (1)/cm
| 60
| 62
| 61
| 60
| 63
| 64
| 62
|
Impact test (2)/cm
| 60
| 62
| 60
| 61
| 63
| 63
| 62 |
(1) Test after 0d (2) test after 30d
As can be seen from the comparison of the data in the table 1, the invention takes 1, 4-cyclohexane dicarboxylic acid, a dihydric alcohol monomer M and isosorbide as monomers, the number average molecular weight of the synthesized polyester is higher than that of polybutylene succinate (PBS), and the tensile breaking strength is 35.1-57.3 MPa higher than that of polybutylene succinate (PBS); polybutylene succinate (PBS) has an elongation at break of 265.0%, while the copolyester CP synthesized by the invention 1 ~CP 7 The elongation at break of (2) is slightly lower than that of polybutylene succinate (PBS). From Table 1 [ eta 1]]And [ eta 2]Compared with the prior art, the bio-based copolyester based on the 4-hydroxybenzaldehyde synthesized by the invention is degraded in natural soil environment, and the intrinsic viscosity of the polyester is reduced by more than half after 3 years, which proves that the molecular weight of the polyester is greatly reduced from the other aspect. Copolyester CP synthesized by the invention 1 ~CP 7 The impact strength of the polymer is about 4-5 times of that of polybutylene succinate (PBS). As can be seen from Table 2, the results of the artificial accelerated aging properties of the powder coating show that the light retention after 360-h light irradiation can still be kept at 90% -93%, and the powder coating prepared from the synthetic polyester of isophthalic acid/terephthalic acid, adipic acid and polyalcohol [2] ([2]Qian Renjun, yang Dong, liao Ping, shao Fei,wang Huili Synthesis and application research of polyester resin for powder coating with Excellent weather resistance [ J]Compared with the Chinese paint (2021,36 (12): 34-39 ") (the light retention rate of the artificial aging test is 83% -87%, and the impact resistance is about 50 cm), the light retention rate of the powder paint and the coating prepared by the invention can reach 90% -93% in the artificial accelerated aging performance, the minimum impact resistance can reach 60cm, and the impact resistance after 30 days can still be basically unchanged, so that the powder paint and the coating have substantial improvement compared with the prior art.
In conclusion, the impact resistance and weather resistance of the super weather-resistant polyester powder coating reported in the prior literature are difficult to meet the requirements of various industries, the paint film is too brittle in the use process, the front and back impact resistance is poor, and the requirements of various aspects of material properties in practical application are difficult to meet. Aiming at the problems in the prior art, the main purpose of the invention is to provide a preparation method and application of a bio-based copolyester based on 4-hydroxybenzaldehyde, in particular to a bio-based copolyester based on 4-hydroxybenzaldehyde prepared by using 4-hydroxybenzaldehyde and isosorbide as raw materials. The degradable copolyester based on biomass as a monomer can be used for preparing a super weather-resistant polyester powder coating, and compared with the existing super weather-resistant polyester powder coating, the degradable copolyester has good weather resistance and mechanical properties and is harmless to the environment. Therefore, the invention patent of the invention 'preparation of bio-based copolyester based on 4-hydroxybenzaldehyde and application thereof' has good market prospect.
While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all such alterations and modifications as fall within the scope of the invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention also include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.