Preparation of high-temperature-resistant modified polyester resin and application of high-temperature-resistant modified polyester resin in non-stick pan coating

Abstract

The invention relates to the technical field of polyester resin, and discloses preparation of high-temperature-resistant modified polyester resin and application of the high-temperature-resistant modified polyester resin in non-stick pan paints.The preparation method includes the steps that iminodiacetonitrile, chloropropyltriethoxysilane, raney nickel, formaldehyde, p-hydroxybenzyl alcohol and the like are used as raw materials and subjected to a substitution reaction, a reduction reaction and a Mannich reaction, silane-containing diol is obtained, and the high-temperature-resistant modified polyester resin is obtained; the preparation method comprises the following steps: carrying out hydrolysis on a siloxane structure contained in silver-loaded nano titanium dioxide to obtain glycol containing silver-loaded nano titanium dioxide, and reacting with trimellitic anhydride under the catalysis of p-toluenesulfonic acid to obtain the high-temperature-resistant modified polyester resin. The modified polyester resin prepared by the invention has excellent mechanical properties, high temperature resistance and antibacterial property, and has a wide application prospect in the field of non-stick pan coatings.

Description

Technical Field

[0001] The invention relates to the technical field of polyester resins, in particular to the preparation of a high-temperature resistant modified polyester resin and the application of the same in non-stick pan coatings. Background Art

[0002] Polyester resin is usually prepared by esterification and polycondensation of dibasic acid and diol. It is widely used in various fields due to its good mechanical properties and chemical corrosion resistance. However, the heat resistance of pure polyester resin is poor, which greatly limits its application field. Therefore, it is necessary to prepare a polyester resin with good heat resistance to adapt to its application in non-stick pan coatings.

[0003] Silver-loaded nano-titanium dioxide is a substance that loads silver ions onto nano-titanium dioxide. It has good antibacterial properties, that is, it uses the silver ions to combine with the sulfhydryl groups of enzyme proteins in bacteria to make the enzyme inactive to kill bacteria. It also uses the nano-titanium dioxide to produce oxygen when excited by light. 2- The ·OH oxidizes the organic compounds in the bacterial cells into carbon dioxide and water, achieving the purpose of sterilization. It is widely used in food packaging, plastics and other fields, but silver-loaded nano-titanium dioxide, as an inorganic substance, is easy to agglomerate in organic matter. Therefore, it is necessary to improve the compatibility of silver-loaded nano-titanium dioxide in organic matter.

[0004] For example, the patent application publication number CN 109627921 A discloses a silver-loaded nano-titanium dioxide antibacterial powder coating. The invention uses epoxy resin, polyester resin, and silver-loaded nano-titanium dioxide as raw materials. The prepared coating has a good antibacterial effect, but does not improve the high temperature resistance of the material. Summary of the invention

[0005] The purpose of the present invention is to overcome one or more deficiencies in the prior art and provide a method for preparing a high temperature resistant modified polyester resin and its application in non-stick pan coatings. The modified polyester resin prepared by the method has antibacterial and high temperature resistant properties.

[0006] In order to achieve the above object, a technical solution adopted by the present invention is:

[0007] A preparation method of a high temperature resistant modified polyester resin is as follows:

[0008] (1) After drying the silver-loaded nano-titanium dioxide, add it to an ethanol solvent, ultrasonically disperse it for 10-20 minutes, heat it to 70-80° C., add silanediol thereto, react for 3-5 hours, and after the reaction is completed, dry, extract, wash with deionized water, and dry to obtain silver-loaded nano-titanium dioxide diol;

[0009] (2) Under a nitrogen atmosphere, adding silver-loaded nano-titanium dioxide diol into a toluene solvent, stirring and dispersing, then adding trimellitic anhydride and p-toluenesulfonic acid thereto, reacting at 100-110° C. for 5-8 hours. After the reaction is completed, vacuum distillation is performed, the mixture is washed with deionized water, and dried to obtain a high-temperature resistant modified polyester resin.

[0010] Preferably, in (1), the amount of silanediol is 10-30% of the mass of the silver-loaded nano-titanium dioxide.

[0011] Preferably, in (2), the mass ratio of silanediol, trimellitic anhydride and p-toluenesulfonic acid is 1:5-8:0.02-0.05.

[0012] Preferably, in (1), the preparation method of the silanediol-containing compound is:

[0013] A1, adding iminodiacetonitrile and chloropropyltriethoxysilane to toluene solvent, stirring and dispersing, reacting at 100-110° C. for 1-2 hours, then adding anhydrous potassium carbonate, and continuing the reaction for 20-24 hours. After the reaction is completed, centrifugation, washing with deionized water, and drying to obtain intermediate 1;

[0014] A2, adding intermediate product 1, Raney nickel and hydrazine hydrate to ethanol solvent, stirring and dispersing, sealing the autoclave, exchanging vacuum and nitrogen 3-5 times, and then filling hydrogen therein, reacting at 60-70° C. for 3-5 hours, and after the reaction, cooling, releasing the pressure, distilling off the solvent, washing with deionized water, and drying to obtain intermediate product 2;

[0015] A3. Add formaldehyde and 4% sodium hydroxide aqueous solution to ethanol solvent, stir and dissolve at 65-75°C, then add p-hydroxybenzyl alcohol, react at 50-60°C for 1-2h, then add intermediate 2, heat to 70-80°C, react for 4-7h, after the reaction, wash with deionized water, rotary evaporate and dry to obtain silanediol.

[0016] More preferably, in A1, the molar ratio of iminodiacetonitrile, chloropropyltriethoxysilane and anhydrous potassium carbonate is 1:1-1.2:1-1.2.

[0017] Further preferably, in A2, the molar ratio of the intermediate product 1, Raney nickel and hydrazine hydrate is 1:2-2.4:10-20.

[0018] Further preferably, in A3, the molar ratio of formaldehyde, p-hydroxybenzyl alcohol and intermediate product 2 is 5-6:2-2.4:1.

[0019] Further preferably, the high temperature resistant modified polyester resin prepared by the preparation method is used in non-stick pan coatings.

[0020] The reaction mechanism of the invention is as follows: using iminodiacetonitrile and chloropropyltriethoxysilane as raw materials, undergoing a substitution reaction to obtain an intermediate product 1, reducing the intermediate product by using Raney nickel and hydrazine hydrate to obtain an intermediate product 2, then subjecting the intermediate product 2 to a Mannich reaction with formaldehyde and p-hydroxybenzyl alcohol to obtain a silane diol, hydrolyzing the siloxane structure contained therein to condense with silver-loaded nano-titanium dioxide to obtain a silver-loaded nano-titanium dioxide diol, and reacting the diol with trimellitic anhydride under the catalysis of p-toluenesulfonic acid to obtain a high-temperature resistant modified polyester resin.

[0021] Due to the application of the above technical solution, the present invention has the following advantages compared with the prior art:

[0022] (1) The silver-loaded nano-titanium dioxide used in the present invention is an inorganic compound with antibacterial properties. Introducing it into polyurethane resin can improve the antibacterial properties of polyester resin. In addition, the silver-loaded nano-titanium dioxide itself is easy to agglomerate and has poor compatibility with organic compounds. The present invention condenses it with organic silane diol to increase its compatibility with polyester resin, reduce the degree of agglomeration, and evenly disperse it in the material, thereby better exerting its antibacterial effect. In addition, when subjected to external impact, it can serve as a stress concentration point to improve the mechanical properties of the material. Moreover, as an inorganic substance, it can improve the high temperature resistance of polyester resin.

[0023] (2) The high temperature resistant modified polyester resin prepared by the present invention contains a large number of branched structures, which can be entangled with each other to form a large number of cross-linking sites. When subjected to external impact, the impact energy can be dispersed along the cross-linking sites, further improving the mechanical properties of the polyester resin material. In addition, the siloxane bond energy contained therein is large and can absorb more energy, thereby synergistically improving the mechanical properties of the material.

[0024] (3) The polyester resin prepared by the present invention contains not only high temperature resistant inorganic materials and high temperature resistant benzene ring rigid structures, but also benzoxazine structures. When heated, the benzoxazine structures can absorb heat to open the rings and crosslink to form a crosslinked network structure, further improving the high temperature resistance of the polyester resin. The modified polyester resin prepared by the present invention has excellent mechanical properties, high temperature resistance and antibacterial properties, and can be used in non-stick pan coatings. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The invention relates to a method for preparing silanediol-containing compounds. DETAILED DESCRIPTION

[0026] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0027] Silver-loaded nano-titanium dioxide was purchased from Hangzhou Wanjing New Materials Co., Ltd.;

[0028] The silicone resin was purchased from Momentive Silicone Materials Shanghai Co., Ltd.

[0029] Example 1

[0030] (1) Add 50 mmol of iminodiacetonitrile and 50 mmol of chloropropyltriethoxysilane to toluene solvent, stir and disperse, react at 105°C for 2 h, then add 60 mmol of anhydrous potassium carbonate and continue to react for 22 h. After the reaction is completed, centrifuge, wash with deionized water, and dry to obtain intermediate 1.

[0031] (2) Add 20 mmol of intermediate 1, 45 mmol of Raney nickel and 200 mmol of hydrazine hydrate to ethanol solvent, stir and disperse, seal the autoclave, exchange vacuum and nitrogen for 3 times, and then fill it with 4 MPa of hydrogen. React at 60 ° C for 4 h. After the reaction is completed, cool and release the pressure, evaporate the solvent, wash with deionized water, and dry to obtain intermediate 2.

[0032] (3) Add 150 mmol of formaldehyde and 5 mL of 4% sodium hydroxide aqueous solution to an ethanol solvent, stir and dissolve at 75°C, then add 60 mmol of p-hydroxybenzyl alcohol, react at 55°C for 2 h, then add 30 mmol of intermediate 2, raise the temperature to 80°C, and react for 4 h. After the reaction, wash with deionized water, rotary evaporate, and dry to obtain silanediol.

[0033] (4) After drying 20 g of silver-loaded nano-titanium dioxide, add it to an ethanol solvent, ultrasonically disperse it for 10 min, heat it to 70°C, add 2 g of silanediol, and react for 3 h. After the reaction is completed, dry, extract, wash with deionized water, and dry to obtain silver-loaded nano-titanium dioxide diol.

[0034] (5) Under a nitrogen atmosphere, 15 g of silver-loaded nano-titanium dioxide diol was added to a toluene solvent and dispersed with stirring. Then, 120 g of trimellitic anhydride and 0.5 g of p-toluenesulfonic acid were added thereto. The mixture was reacted at 100 °C for 8 h. After the reaction was completed, the mixture was distilled under reduced pressure, washed with deionized water, and dried to obtain a high-temperature resistant modified polyester resin.

[0035] Example 2

[0036] (1) Add 50 mmol of iminodiacetonitrile and 60 mmol of chloropropyltriethoxysilane to toluene solvent, stir and disperse, react at 100°C for 1 hour, then add 55 mmol of anhydrous potassium carbonate and continue to react for 20 hours. After the reaction is completed, centrifuge, wash with deionized water, and dry to obtain intermediate 1.

[0037] (2) Add 20 mmol of intermediate 1, 40 mmol of Raney nickel and 300 mmol of hydrazine hydrate to ethanol solvent, stir and disperse, seal the autoclave, exchange vacuum and nitrogen for 4 times, and then fill it with 4 MPa of hydrogen. React at 70°C for 3 h. After the reaction is completed, cool and release the pressure, evaporate the solvent, wash with deionized water, and dry to obtain intermediate 2.

[0038] (3) Add 160 mmol of formaldehyde and 5 mL of 4% sodium hydroxide aqueous solution to an ethanol solvent, stir and dissolve at 70°C, then add 65 mmol of p-hydroxybenzyl alcohol, react at 50°C for 2 h, then add 30 mmol of the intermediate 2, raise the temperature to 75°C, and react for 5 h. After the reaction, wash with deionized water, rotary evaporate, and dry to obtain silanediol.

[0039] (4) After drying 20 g of silver-loaded nano-titanium dioxide, add it to an ethanol solvent, ultrasonically disperse it for 20 min, heat it to 75 ° C, add 4 g of silane diol, react for 4 h, and after the reaction is completed, dry, extract, wash with deionized water, and dry to obtain silver-loaded nano-titanium dioxide diol.

[0040] (5) Under a nitrogen atmosphere, 15 g of silver-loaded nano-titanium dioxide diol was added to a toluene solvent and dispersed with stirring. Then, 110 g of trimellitic anhydride and 0.75 g of p-toluenesulfonic acid were added thereto. The mixture was reacted at 105 °C for 6 h. After the reaction was completed, the mixture was distilled under reduced pressure, washed with deionized water, and dried to obtain a high-temperature resistant modified polyester resin.

[0041] Example 3

[0042] (1) Add 50 mmol of iminodiacetonitrile and 55 mmol of chloropropyltriethoxysilane to toluene solvent, stir and disperse, react at 110°C for 1 hour, then add 50 mmol of anhydrous potassium carbonate and continue to react for 24 hours. After the reaction is completed, centrifuge, wash with deionized water, and dry to obtain intermediate 1.

[0043] (2) Add 20 mmol of intermediate 1, 48 mmol of Raney nickel and 400 mmol of hydrazine hydrate to ethanol solvent, stir and disperse, seal the autoclave, exchange vacuum and nitrogen for 5 times, and then fill it with 4 MPa of hydrogen. React at 65 ° C for 5 h. After the reaction is completed, cool and release the pressure, evaporate the solvent, wash with deionized water, and dry to obtain intermediate 2.

[0044] (3) Add 180 mmol of formaldehyde and 5 mL of 4% sodium hydroxide aqueous solution to an ethanol solvent, stir and dissolve at 65°C, then add 72 mmol of p-hydroxybenzyl alcohol, react at 60°C for 1 h, then add 30 mmol of the intermediate 2, raise the temperature to 70°C, and react for 7 h. After the reaction, wash with deionized water, rotary evaporate, and dry to obtain silanediol.

[0045] (4) After drying 20 g of silver-loaded nano-titanium dioxide, add it to an ethanol solvent, ultrasonically disperse it for 15 min, heat it to 80 °C, add 5 g of silanediol, and react for 5 h. After the reaction is completed, dry, extract, wash with deionized water, and dry to obtain silver-loaded nano-titanium dioxide diol.

[0046] (5) Under a nitrogen atmosphere, 15 g of silver-loaded nano-titanium dioxide diol was added to a toluene solvent and dispersed with stirring. Then, 95 g of trimellitic anhydride and 0.3 g of p-toluenesulfonic acid were added thereto. The mixture was reacted at 110° C. for 5 h. After the reaction was completed, the mixture was distilled under reduced pressure, washed with deionized water, and dried to obtain a high-temperature resistant modified polyester resin.

[0047] Example 4

[0048] (1) Add 50 mmol of iminodiacetonitrile and 52 mmol of chloropropyltriethoxysilane to toluene solvent, stir and disperse, react at 105°C for 1 hour, then add 55 mmol of anhydrous potassium carbonate and continue to react for 23 hours. After the reaction is completed, centrifuge, wash with deionized water, and dry to obtain intermediate 1.

[0049] (2) Add 20 mmol of intermediate 1, 45 mmol of Raney nickel and 350 mmol of hydrazine hydrate to ethanol solvent, stir and disperse, seal the autoclave, exchange vacuum and nitrogen for 4 times, and then fill it with 4 MPa of hydrogen. React at 70°C for 3 h. After the reaction is completed, cool and release the pressure, evaporate the solvent, wash with deionized water, and dry to obtain intermediate 2.

[0050] (3) Add 170 mmol of formaldehyde and 5 mL of 4% sodium hydroxide aqueous solution to an ethanol solvent, stir and dissolve at 65°C, then add 68 mmol of p-hydroxybenzyl alcohol, react at 60°C for 2 h, then add 30 mmol of intermediate 2, raise the temperature to 75°C, and react for 6 h. After the reaction, wash with deionized water, rotary evaporate, and dry to obtain silanediol.

[0051] (4) After drying 20 g of silver-loaded nano-titanium dioxide, add it to an ethanol solvent, ultrasonically disperse it for 15 min, heat it to 75 °C, add 6 g of silane diol, and react for 3 h. After the reaction is completed, dry, extract, wash with deionized water, and dry to obtain silver-loaded nano-titanium dioxide diol.

[0052] (5) Under a nitrogen atmosphere, 15 g of silver-loaded nano-titanium dioxide diol was added to a toluene solvent and dispersed with stirring. Then, 75 g of trimellitic anhydride and 0.3 g of p-toluenesulfonic acid were added thereto. The mixture was reacted at 105° C. for 7 h. After the reaction was completed, the mixture was distilled under reduced pressure, washed with deionized water, and dried to obtain a high-temperature resistant modified polyester resin.

[0053] Example 5

[0054] 50 g of the high temperature resistant modified polyester resin prepared in Example 1, 50 g of silicone resin, 1 g of dispersant BYK163, 0.2 g of defoamer BYK-011, 0.2 g of anti-settling agent 8900-20X, and 0.8 g of leveling agent BYK310 were mixed evenly, and 10 g of xylene and 10 g of butyl acetate were added thereto, and the mixture was ground with a sand grinder and filtered to obtain a coating.

[0055] Example 6

[0056] 50 g of the high temperature resistant modified polyester resin prepared in Example 2, 50 g of silicone resin, 1 g of dispersant BYK163, 0.2 g of defoamer BYK-011, 0.2 g of anti-settling agent 8900-20X, and 0.8 g of leveling agent BYK310 were mixed evenly, and 10 g of xylene and 10 g of butyl acetate were added thereto, and the mixture was ground with a sand grinder and filtered to obtain a coating.

[0057] Example 7

[0058] 50 g of the high temperature resistant modified polyester resin prepared in Example 3, 50 g of silicone resin, 1 g of dispersant BYK163, 0.2 g of defoamer BYK-011, 0.2 g of anti-settling agent 8900-20X, and 0.8 g of leveling agent BYK310 were mixed evenly, and 10 g of xylene and 10 g of butyl acetate were added thereto, and the mixture was ground with a sand grinder and filtered to obtain a coating.

[0059] Example 8

[0060] 50 g of the high temperature resistant modified polyester resin prepared in Example 4, 50 g of silicone resin, 1 g of dispersant BYK163, 0.2 g of defoamer BYK-011, 0.2 g of anti-settling agent 8900-20X, and 0.8 g of leveling agent BYK310 were mixed evenly, and 10 g of xylene and 10 g of butyl acetate were added thereto, and the mixture was ground with a sand grinder and filtered to obtain a coating.

[0061] The coating was sprayed on the dry tinplate, placed at 250°C, baked for 30 minutes, taken out, and cooled to room temperature to obtain a coating sample.

[0062] Impact testing was performed according to ASTM D2794-2006.

[0063] Place the coating sample at 300℃ and bake for 2h, then observe whether the coating film has any peeling or cracking.

[0064] Table 1:

[0065] Impact resistance (9J) High temperature resistance test phenomenon Example 5 pass No falling off, no cracking Example 6 pass No falling off, no cracking Example 7 pass No falling off, no cracking Example 8 pass No falling off, no cracking Comparative Example 1 Not passed No falling off, cracking

[0066] Comparative Example 1 is a commercially available polyester coating.

[0067] It can be seen from the table that the coating prepared from the high temperature resistant modified polyester resin of the present invention has good mechanical properties and high temperature resistance.

[0068] The antibacterial properties were tested according to GB / T 15979-2002.

[0069] Table 2:

[0070] Antibacterial rate (%) Example 5 96.8 Example 6 97.5 Example 7 98.9 Example 8 99.9 Comparative Example 1 54.2

[0071] Comparative Example 1 is a commercially available polyester coating.

[0072] It can be seen from the table that the coating prepared from the high temperature resistant modified polyester resin of the present invention has good antibacterial properties, and the antibacterial rate can reach up to 99.9%.

[0073] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A preparation method of a high temperature resistant modified polyester resin, characterized in that: The preparation method is: (1) After drying the silver-loaded nano-titanium dioxide, add it to an ethanol solvent, ultrasonically disperse it for 10-20 minutes, heat it to 70-80° C., add silanediol thereto, react for 3-5 hours, and after the reaction is completed, dry, extract, wash with deionized water, and dry to obtain silver-loaded nano-titanium dioxide diol; (2) Under a nitrogen atmosphere, adding silver-loaded nano-titanium dioxide diol into a toluene solvent, stirring and dispersing, then adding trimellitic anhydride and p-toluenesulfonic acid thereto, reacting at 100-110° C. for 5-8 hours. After the reaction is completed, vacuum distillation is performed, the mixture is washed with deionized water, and dried to obtain a high-temperature resistant modified polyester resin.

2. The preparation of the high temperature resistant modified polyester resin according to claim 1, characterized in that: In the above (1), the amount of silanediol used is 10-30% of the mass of the silver-loaded nano-titanium dioxide.

3. The preparation of the high temperature resistant modified polyester resin according to claim 1, characterized in that: In the above (2), the mass ratio of silanediol, trimellitic anhydride and p-toluenesulfonic acid is 1:5-8:0.02-0.

05.

4. The preparation of the high temperature resistant modified polyester resin according to claim 1, characterized in that: In the above (1), the preparation method of silanediol is: A1, adding iminodiacetonitrile and chloropropyltriethoxysilane to toluene solvent, stirring and dispersing, reacting at 100-110° C. for 1-2 hours, then adding anhydrous potassium carbonate, and continuing the reaction for 20-24 hours. After the reaction is completed, centrifugation, washing with deionized water, and drying to obtain intermediate 1; A2, adding intermediate product 1, Raney nickel and hydrazine hydrate to ethanol solvent, stirring and dispersing, sealing the autoclave, exchanging vacuum and nitrogen 3-5 times, and then filling hydrogen therein, reacting at 60-70° C. for 3-5 hours, and after the reaction, cooling, releasing the pressure, distilling off the solvent, washing with deionized water, and drying to obtain intermediate product 2; A3. Add formaldehyde and 4% sodium hydroxide aqueous solution to ethanol solvent, stir and dissolve at 65-75°C, then add p-hydroxybenzyl alcohol, react at 50-60°C for 1-2h, then add intermediate 2, heat to 70-80°C, react for 4-7h, after the reaction, wash with deionized water, rotary evaporate and dry to obtain silanediol.

5. The preparation of the high temperature resistant modified polyester resin according to claim 4, characterized in that: In the A1, the molar ratio of iminodiacetonitrile, chloropropyltriethoxysilane and anhydrous potassium carbonate is 1:1-1.2:1-1.

2.

6. The preparation of the high temperature resistant modified polyester resin according to claim 4, characterized in that: In A2, the molar ratio of the intermediate product 1, Raney nickel and hydrazine hydrate is 1:2-2.4:10-20.

7. The preparation of the high temperature resistant modified polyester resin according to claim 4, characterized in that: In A3, the molar ratio of formaldehyde, p-hydroxybenzyl alcohol and intermediate product 2 is 5-6:2-2.4:

1.

8. Use of a high temperature resistant modified polyester resin prepared by the preparation method according to any one of claims 1 to 7 in non-stick pan coatings.

Images