A bio-based waterproof and environmentally friendly coating and preparation method thereof

Abstract

The present invention provides a bio-based waterproof and environmentally friendly coating precursor provided by the present invention, characterized in that it contains 2,5-furandicarboxylic acid konjac polysaccharide; the 2,5-furandicarboxylic acid konjac polysaccharide is made of the following raw materials in parts by weight: 100 konjac polysaccharide; 100-120 2,5-furandicarboxylic acid. The preparation method of the bio-based waterproof and environmentally friendly coating precursor of the present invention is: konjac polysaccharide and 2,5-furandicarboxylic acid are added to a reactor, a catalyst is added, and under nitrogen protection, the reaction is carried out at a temperature of 180-220° C. for 3-5 hours; during the reaction, the water is removed by reducing the pressure; and 2,5-furandicarboxylic acid konjac polysaccharide is generated, which is the bio-based waterproof and environmentally friendly coating precursor. The paint film generated by the cross-linking reaction between 2,5-furandicarboxylic acid konjac polysaccharide and isocyanate has good hardness, rigidity, flexibility, acid and alkali resistance, and is safe and non-toxic; the cross-linked product of poly 2,5-furandicarboxylic acid konjac polysaccharide isocyanate can form a swollen and dense hydrophobic layer on the surface after contacting water.

Description

Technical Field

[0001] The invention belongs to the technical field of coatings and relates to a bio-based waterproof and environmentally friendly coating and a preparation method thereof. Background Art

[0002] Konjac polysaccharide is a high molecular weight water-soluble polysaccharide extracted from the tuber of konjac (Amorphophallus konjac C.Koch).

[0003] Since konjac polysaccharide is rich in -OH and has strong swelling active groups, it is easy to combine with other groups in the coating, such as -COOH and -NCO, to form resin. Applying konjac polysaccharide to bio-based environmentally friendly waterproof coatings is an interesting research topic. Summary of the invention

[0004] In view of the above defects, the present invention aims to overcome the deficiencies of the prior art and prepare a bio-based waterproof and environmentally friendly coating.

[0005] To achieve the above object, the present invention provides a bio-based waterproof and environmentally friendly coating precursor, characterized in that it contains 2,5-furandicarboxylic acid konjac polysaccharide. The 2,5-furandicarboxylic acid konjac polysaccharide is made from the following raw materials in parts by weight:

[0006] Konjac polysaccharide 100;

[0007] 2,5-Furandicarboxylic acid 100-120.

[0008] Konjac polysaccharide is a high molecular weight water-soluble polysaccharide extracted from the tuber of konjac (Amorphophallus konjac C.Koch). It is a long-chain molecule formed by copolymerization of D-glucose and D-mannose residues with a 1:1.6 or 2:3 molar ratio through β-1,4 glycosidic bonds. An acetyl group is connected to every 19 sugar residues (C-6 position) in the molecule. The molecular weight of D-glucose is 180.16. 2,5-furandicarboxylic acid has a molecular weight of 156.09 due to the molecular structure of the furan ring similar to the aromatic ring, and can be used to prepare bio-based polymer materials.

[0009] The preparation method of the bio-based waterproof and environmentally friendly coating precursor is:

[0010] Konjac polysaccharide and 2,5-furandicarboxylic acid are added into a reactor, and a catalyst is added. Under nitrogen protection, the reaction is carried out at a temperature of 180-220°C for 3-5 hours. During the reaction, the water is removed by reducing the pressure to generate 2,5-furandicarboxylic acid konjac polysaccharide, which is a precursor of a bio-based waterproof and environmentally friendly coating.

[0011] The catalyst can be selected from Lewis acids, metal salts or cation exchange resins.

[0012] The catalyst is preferably phosphoric acid, and the amount of phosphoric acid used is 0.5-1% of the total weight of the reactants. The advantage of selecting phosphoric acid is that after the catalytic reaction, phosphoric acid can be phosphatized with konjac polysaccharide, and the reaction product is konjac polysaccharide phosphate, which has the effects of chelating agent and surfactant; at the same time, it has a relatively good flame retardant effect and is safe and non-toxic. After the reaction, the catalyst does not need to be separated, which can save water, electricity, chemical reagents, etc. required for removing the catalyst, and has significant energy-saving and environmental protection benefits.

[0013] The present invention provides a bio-based waterproof and environmentally friendly coating, which is characterized by: comprising component A and component B;

[0014] The component A is prepared from the following raw materials in the following weight ratios:

[0015] 2,5-furandicarboxylic acid konjac polysaccharide 100;

[0016] Isocyanate 20-25.

[0017] The component B is prepared from the following raw materials in the following weight ratios:

[0018]

[0019]

[0020] The isocyanate is selected from one or more of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.

[0021] The acrylic ester can be selected from ethyl acrylate, propyl acrylate, butyl acrylate and one or more thereof, and used as a liquid base material in a waterproof and environmentally friendly coating.

[0022] The sodium silicate and bentonite provide good base materials and pigments for waterproof and environmentally friendly coatings, and a suitable proportion can enhance the impact resistance of the coating film.

[0023] The tert-butyl hydroperoxide is used as an initiator in the polymerization process of 2,5-furandicarboxylic acid konjac polysaccharide, acrylate and methacrylic acid, and is safe and non-toxic.

[0024] The stannous octoate can act as a catalyst in the polyurethane reaction of isocyanate, 2,5-furandicarboxylic acid konjac polysaccharide and propylene glycol, and after the reaction is completed, it can be used as a drying agent in the waterproof and environmentally friendly coating, which is safe and non-toxic.

[0025] The ultraviolet absorber is selected from one or more of the commercial ultraviolet absorber UV-P, ultraviolet absorber UV-O, ultraviolet absorber UV-9, ultraviolet absorber UV-326 and ultraviolet absorber UV-327.

[0026] The cyclopentane salt is selected from one of calcium cyclopentaneate, zinc cyclopentaneate, barium cyclopentaneate and manganese cyclopentaneate or a mixture of several of them, and is used as a drying agent for waterproof and environmentally friendly coatings, and also has a certain anti-aging effect.

[0027] In the present invention, the preparation method of the bio-based waterproof and environmentally friendly coating is:

[0028] Preparation of component A: Weigh 2,5-furandicarboxylic acid konjac polysaccharide and isocyanate in proportion, add them into a reactor, evacuate, stir at 110-120° C. until no bubbles are generated, cool to 75-80° C., mix and stir for 60-90 minutes, and naturally cool to room temperature to obtain component A.

[0029] Preparation of component B: Add acrylate, methacrylic acid, propylene glycol and tert-butyl hydroperoxide into a reactor, evacuate and react at 110-120°C for 4-5 hours. After cooling to room temperature, add stannous octoate, sodium silicate, bentonite, ultraviolet absorber and cyclopentaneate into a stirrer, mix well and grind to obtain component B.

[0030] The method of using the bio-based waterproof and environmentally friendly coating in the present invention is:

[0031] Mix the above components A and B in a weight ratio of 1:1.5-2, stir mechanically for 5-10 minutes, and then apply. Generally, after 5 days of application, test the relevant indicators according to JC / T500-1992 standard.

[0032] Functions and effects of the present invention

[0033] In the present invention, konjac polysaccharide and 2,5-furandicarboxylic acid are subjected to an esterification reaction under the catalytic action of a catalyst to generate 2,5-furandicarboxylic acid konjac polysaccharide; and then the poly-2,5-furandicarboxylic acid konjac polysaccharide generated by a polymerization reaction under the initiation of an initiator has thickening and stabilizing effects in the process of preparing paints, and the paint film generated by the cross-linking reaction with isocyanate has good hardness, rigidity, flexibility, acid and alkali resistance, and is safe and non-toxic; and at the same time, because the konjac polysaccharide molecules have rapid swelling properties, the poly-2,5-furandicarboxylic acid konjac polysaccharide isocyanate cross-linked product can form a swollen and dense hydrophobic layer on the surface after it meets water.

[0034] In the present invention, isocyanate can react with -OH in the components to generate polyurethane which is the base material of the coating.

[0035] In the present invention, acrylate, methacrylic acid and propylene glycol can generate poly(meth)acrylate coating base material under the action of catalyst and initiator.

[0036] In the present invention, sodium silicate and bentonite provide good base materials and pigments for waterproof and environmentally friendly coatings, and a suitable proportion can enhance the impact resistance of the coating film.

[0037] In the present invention, tert-butyl hydroperoxide is used as an initiator in the polymerization process of 2,5-furandicarboxylic acid konjac polysaccharide, acrylate and methacrylic acid, and is safe and non-toxic.

[0038] In the present invention, the ultraviolet absorber can accelerate the curing of polyurethane.

[0039] In the present invention, the cyclopentane salt can play a surface drying role and can be used as an excellent drying agent, and also has a certain anti-aging effect.

[0040] In addition, the bio-based waterproof and environmentally friendly coating obtained by adopting the formulation system and preparation method of the present invention can realize the organic integration of various components, and can complement each other without affecting the effectiveness of each component, thereby achieving excellent performance of environmentally friendly coating. DETAILED DESCRIPTION

[0041] Embodiment 1

[0042] Weigh 1000g of konjac polysaccharide and 1200g of 2,5-furandicarboxylic acid into a reactor, add 10g of aminosulfonic acid as a catalyst, and react at 180°C for 5 hours under nitrogen protection; reduce the pressure during the reaction to remove moisture; generate 2,5-furandicarboxylic acid konjac polysaccharide, which is a bio-based waterproof and environmentally friendly coating precursor.

[0043] The preparation method of the bio-based waterproof and environmentally friendly coating is as follows:

[0044] Preparation of component A: Weigh 1000 g of a bio-based waterproof and environmentally friendly coating precursor (2,5-furandicarboxylic acid konjac polysaccharide) and 250 g of toluene diisocyanate (TDI) in proportion, add them into a reactor, evacuate the mixture, stir at 110°C until no bubbles are generated, cool to 75°C, mix and stir for 90 minutes, and naturally cool to room temperature to obtain component A.

[0045] Preparation of component B: 1000 g of ethyl acrylate, 300 g of methacrylic acid, 300 g of propylene glycol, and 10 g of tert-butyl hydroperoxide were added to a reactor, vacuumed, and reacted at 120° C. for 4 hours. After cooling to room temperature, 5 g of stannous octoate, 200 g of sodium silicate, 300 g of bentonite, 5 g of ultraviolet absorber (UV-P), and 10 g of calcium cyclohexaneate were added to a stirrer, mixed evenly, and then ground to obtain component B.

[0046] Mix the above component A and component B in a weight ratio of 1:2, stir with a stirrer for 10 minutes, and then apply it.

[0047] The coating thickness is 2mm±0.1mm in several times. After 7 days of application, the tensile strength, elongation at break, high and low temperature resistance, impermeability and other indicators are tested according to JC / T500-1996 standard. The result is qualified.

[0048] Embodiment 2

[0049] Weigh 1000g of konjac polysaccharide and 1100g of 2,5-furandicarboxylic acid into a reactor, add 20g of phosphoric acid, and react at 220°C for 3 hours under nitrogen protection; reduce the pressure during the reaction to remove moisture; generate 2,5-furandicarboxylic acid konjac polysaccharide, which is a bio-based waterproof and environmentally friendly coating precursor.

[0050] The preparation method of the bio-based waterproof and environmentally friendly coating is as follows:

[0051] Preparation of component A: Weigh 1000 g of a bio-based waterproof and environmentally friendly coating precursor (2,5-furandicarboxylic acid konjac polysaccharide) and 200 g of isophorone diisocyanate (IPDI) in proportion, add them into a reactor, evacuate the mixture, and stir at 120°C until no bubbles are generated. Cool the mixture to 80°C and stir for 60 minutes. Naturally cool the mixture to room temperature to obtain component A.

[0052] Preparation of component B: 1000 g of propyl acrylate, 200 g of methacrylic acid, 400 g of propylene glycol, and 5 g of tert-butyl hydroperoxide are added to a reactor, vacuumed, and reacted at 110° C. for 5 hours. After cooling to room temperature, 10 g of stannous octoate, 300 g of sodium silicate, 200 g of bentonite, 10 g of ultraviolet absorber (UV-O), and 5 g of zinc cyclohexane are added to a stirrer, mixed evenly, and then ground to obtain component B.

[0053] Mix the above component A and component B in a weight ratio of 1:1.5, stir with a stirrer for 5 minutes, and then apply it.

[0054] The coating thickness is 2mm±0.1mm after applying for 7 days, and then the relevant indicators are tested according to JC / T500-1996. The result is qualified.

[0055] Embodiment 3

[0056] Weigh 1000 g of konjac polysaccharide and 1000 g of 2,5-furandicarboxylic acid into a reactor, add 10 g of phosphoric acid, and react at 200° C. for 4 hours under nitrogen protection; reduce the pressure during the reaction to remove moisture; generate 2,5-furandicarboxylic acid konjac polysaccharide, which is a bio-based waterproof and environmentally friendly coating precursor.

[0057] The preparation method of the bio-based waterproof and environmentally friendly coating is as follows:

[0058] Preparation of component A: Weigh 1000 g of a bio-based waterproof and environmentally friendly coating precursor (2,5-furandicarboxylic acid konjac polysaccharide) and 210 g of dicyclohexylmethane diisocyanate (HMDI) in proportion, add them into a reactor, evacuate the reactor, stir at 110°C until no bubbles are generated, cool to 80°C, mix and stir for 70 minutes, and naturally cool to room temperature to obtain component A.

[0059] Preparation of component B: 1000 g of ethyl acrylate, 250 g of methacrylic acid, 350 g of propylene glycol, and 6 g of tert-butyl hydroperoxide were added to a reactor, vacuumed, and reacted at 120° C. for 4 hours. After cooling to room temperature, 7 g of stannous octoate, 250 g of sodium silicate, 250 g of bentonite, 8 g of ultraviolet absorber (UV-9), and 7 g of calcium cyclohexaneate were added to a stirrer, mixed evenly, and then ground to obtain component B.

[0060] Mix the above component A and component B in a weight ratio of 1:2, stir with a stirrer for 7 minutes, and then apply it.

[0061] The coating thickness is 2mm±0.1mm after applying for 7 days, and then the relevant indicators are tested according to JC / T500-1996. The result is qualified.

[0062] Embodiment 4

[0063] Weigh 1000g of konjac polysaccharide and 1100g of 2,5-furandicarboxylic acid into a reactor, add 18g of phosphoric acid, and react at 200°C for 4 hours under nitrogen protection; reduce the pressure during the reaction to remove moisture; generate 2,5-furandicarboxylic acid konjac polysaccharide, which is a bio-based waterproof and environmentally friendly coating precursor.

[0064] The preparation method of the bio-based waterproof and environmentally friendly coating is as follows:

[0065] Preparation of component A: Weigh 1000 g of a bio-based waterproof and environmentally friendly coating precursor (2,5-furandicarboxylic acid konjac polysaccharide) and 220 g of isophorone diisocyanate (IPDI) in proportion, add them into a reactor, evacuate the mixture, and stir at 115±1°C until no bubbles are generated. Cool the mixture to 77±1°C and stir for 80 minutes. Naturally cool the mixture to room temperature to obtain component A.

[0066] Preparation of component B: 1000 g of propyl acrylate, 260 g of methacrylic acid, 360 g of propylene glycol, and 7 g of tert-butyl hydroperoxide are added to a reactor, evacuated, and reacted at 120° C. for 4 hours. After cooling to room temperature, 6 g of stannous octoate, 240 g of sodium silicate, 270 g of bentonite, 6 g of ultraviolet absorber (UV-326), and 8 g of barium cyclohexane are added to a stirrer, mixed evenly, and then ground to obtain component B.

[0067] Mix the above component A and component B in a weight ratio of 1:2, stir with a stirrer for 8 minutes, and then apply it.

[0068] The coating thickness is 2mm±0.1mm after applying for 6 days, and then the relevant indicators are tested according to JC / T500-1996. The result is qualified.

[0069] Embodiment 5

[0070] Weigh 1000g of konjac polysaccharide and 1100g of 2,5-furandicarboxylic acid into a reactor, add 16g of phosphoric acid, and react at 200°C for 4 hours under nitrogen protection; reduce the pressure during the reaction to remove moisture; generate 2,5-furandicarboxylic acid konjac polysaccharide, which is a bio-based waterproof and environmentally friendly coating precursor.

[0071] The preparation method of the bio-based waterproof and environmentally friendly coating is as follows:

[0072] Preparation of component A: Weigh 1000 g of a bio-based waterproof and environmentally friendly coating precursor (2,5-furandicarboxylic acid konjac polysaccharide) and 230 g of diphenylmethane diisocyanate (MDI) in proportion, add them into a reactor, evacuate the reactor, stir at 110°C until no bubbles are generated, cool to 77±1°C, mix and stir for 80 minutes, and naturally cool to room temperature to obtain component A.

[0073] Preparation of component B: 1000 g of butyl acrylate, 260 g of methacrylic acid, 330 g of propylene glycol, and 8 g of tert-butyl hydroperoxide were added to a reactor, vacuumed, and reacted at 120° C. for 4 hours. After cooling to room temperature, 9 g of stannous octoate, 210 g of sodium silicate, 280 g of bentonite, 9 g of ultraviolet absorber (UV-327), and 9 g of manganese cyclohexane were added to a stirrer, mixed evenly, and then ground to obtain component B.

[0074] Mix the above component A and component B in a weight ratio of 1:2, stir with a stirrer for 10 minutes, and then apply it.

[0075] The coating thickness is 2mm±0.1mm after applying for 5 days. Then the tensile strength, elongation at break, high and low temperature resistance, water impermeability and other indicators are tested according to JC / T500-1996 standard. The result is qualified.

Claims

1. A bio-based waterproof and environmentally friendly coating precursor, characterized in that: It is composed of 2,5-furandicarboxylic acid konjac polysaccharide; The 2,5-furandicarboxylic acid konjac polysaccharide is prepared from the following raw materials in parts by weight: Konjac polysaccharide 100; 2,5-furandicarboxylic acid 100-120; The preparation method of the 2,5-furandicarboxylic acid konjac polysaccharide is as follows: Konjac polysaccharide and 2,5-furandicarboxylic acid are added into a reactor, and a catalyst is added. Under nitrogen protection, the reaction is carried out at a temperature of 180-220°C for 3-5 hours. During the reaction, the water is removed by reducing the pressure to generate 2,5-furandicarboxylic acid konjac polysaccharide, which is a precursor of a bio-based waterproof and environmentally friendly coating.

2. The bio-based waterproof and environmentally friendly coating produced by the bio-based waterproof and environmentally friendly coating precursor according to claim 1, characterized in that: It is composed of component A and component B; The component A is prepared from the following raw materials in the following weight ratios: The 2,5-furandicarboxylic acid konjac polysaccharide 100 as claimed in claim 1; Isocyanate 20-25; The component B is prepared from the following raw materials in the following weight ratios:

3. A bio-based waterproof and environmentally friendly coating as claimed in claim 2, characterized in that: The isocyanate is selected from one or more of toluene diisocyanate, isophorone diisocyanate, diphenylmethane diisocyanate, dicyclohexylmethane diisocyanate, hexamethylene diisocyanate, and lysine diisocyanate.

4. A bio-based waterproof and environmentally friendly coating as claimed in claim 2, characterized in that: The acrylic acid ester is selected from one or more of ethyl acrylate, propyl acrylate and butyl acrylate.

5. A bio-based waterproof and environmentally friendly coating as claimed in claim 2, characterized in that: The ultraviolet absorber is selected from one or more of the commercial ultraviolet absorber UV-P, ultraviolet absorber UV-O, ultraviolet absorber UV-9, ultraviolet absorber UV-326 and ultraviolet absorber UV-327.

6. A bio-based waterproof and environmentally friendly coating as claimed in claim 2, characterized in that: The naphthenate is selected from one of calcium naphthenate, zinc naphthenate, barium naphthenate and manganese naphthenate or a mixture of several of them.

7. A method for preparing a bio-based waterproof and environmentally friendly coating according to any one of claims 2 to 6, characterized in that: Preparation of component A: weigh 2,5-furandicarboxylic acid konjac polysaccharide and isocyanate in proportion, add them into a reactor, evacuate, stir at 110-120°C until no bubbles are generated, cool to 75-80°C, mix and stir for 60-90 minutes, and naturally cool to room temperature to obtain component A; Preparation of component B: Add acrylate, methacrylic acid, propylene glycol and tert-butyl hydroperoxide into a reactor, evacuate and react at 110-120°C for 4-5 hours. After cooling to room temperature, add stannous octoate, sodium silicate, bentonite, ultraviolet absorber and cyclopentaneate into a stirrer, mix well and grind to obtain component B.

8. A method for using a bio-based waterproof and environmentally friendly coating as claimed in any one of claims 2 to 6, characterized in that: The component A and the component B are mixed in a weight ratio of 1:1.5-2, mechanically stirred for 5-10 minutes, and then applied.

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