Preparation method and application of formaldehyde-free flame-retardant biomass-based adhesive

Abstract

The invention provides a preparation method and application of a formaldehyde-free flame-retardant biomass-based adhesive. Belongs to the technical field of adhesives. The formaldehyde-free flame-retardant biomass-based adhesive is prepared from polyphenol, polyhydric alcohol and a solvent; the formaldehyde-free flame-retardant biomass-based adhesive constructs a three-dimensional bonding flame-retardant network based on high-density secondary bonds, and can be used for preparing flexible and non-flexible functional materials with high static bending intensity, zero formaldehyde and efficient flame retardance in a bonding manner.

Description

Technical Field

[0001] The present invention relates to the field of adhesives, and particularly relates to a preparation method and application of a formaldehyde-free flame-retardant biomass-based adhesive. Background Art

[0002] Formaldehyde-free adhesives are an important development direction in the field of adhesives. Biomass has the characteristics of efficient non-covalent bond action endowed by multiple functional groups, so it is expected to be used to develop new formaldehyde-free high-performance adhesives. Plant polyphenols are natural polyphenolic substances, which have the characteristics of amphiphilicity, greenness, environmental protection, and wide sources (Hao B, Wang F, Huang H, et al. Tanninfoam immobilized with ferric ions for efficient removal of ciprofloxacin at low concentrations [J]. Journal of Hazardous Materials, 2021, 414: 125567.). However, plant polyphenols contain a large number of phenolic hydroxyl groups, and the intermolecular force is strong. High-concentration plant polyphenols are prone to form supramolecular aggregates in solvents, resulting in gel problems, which is a bottleneck problem affecting the development of plant polyphenol-based adhesives (Liu X, Sun J. Polymeric materials reinforced by noncovalent aggregates of polymer chains [J]. Aggregate, 2021, 2(5): e109.). In addition, when developing new plant polyphenol-based adhesives, the influence of bonding flame retardancy also needs to be considered. However, the negative impact of plant polyphenol gelation on the bonding structure makes it extremely challenging to achieve flame-retardant bonding. Therefore, developing a new type of plant polyphenol-based formaldehyde-free flame-retardant biomass-based adhesive with excellent fluidity has important application value but also technical challenges. Summary of the Invention

[0003] The purpose of the present invention is to overcome the shortcomings of the prior art and provide a preparation method and application of a formaldehyde-free flame-retardant biomass-based adhesive; belonging to the technical field of adhesives; the formaldehyde-free flame-retardant biomass-based adhesive is composed of polyphenols, polyols, and a solvent; the formaldehyde-free flame-retardant biomass-based adhesive constructs a three-dimensional bonding flame-retardant network based on high-density secondary bonds, and can be used to bond and prepare flexible and non-flexible functional materials with high static bending strength, zero formaldehyde, and high-efficiency flame retardancy.

[0004] To achieve the above technical effects, the following technical solutions are adopted: A formaldehyde-free flame-retardant biomass-based adhesive is composed of polyphenols, polyols, and a solvent.

[0005] Further, the polyphenol is a plant polyphenol.

[0006] Further, the polyol is one or more of PBA, PEG, and PVA.

[0007] Further, the solvent is a water-organic solvent mixture.

[0008] Further, in the water-organic solvent mixture, the organic solvent is one or more of acetone, N,N-dimethylformamide DMF, pyridine, methanol, ethanol, ethylene glycol, isopropanol, 1,2-propanediol, and 1,3-propanediol.

[0009] Further, the formaldehyde-free flame-retardant biomass-based adhesive can achieve formaldehyde-free high-performance bonding and flame-retardant bonding of various substrates, and can be used to prepare flexible and non-flexible functional materials.

[0010] The beneficial effects of the present invention are as follows: The present invention discloses a preparation method and application of a formaldehyde-free flame-retardant biomass-based adhesive. Aiming at the problems of gelation, low bonding strength, and poor flame-retardant performance existing in traditional plant polyphenol-based adhesives, the formaldehyde-free flame-retardant biomass-based adhesive prepared by the present invention has excellent anti-gel performance, can achieve formaldehyde-free high-strength bonding of various substrates, the bonding strength can reach 7.8 MPa, and has the characteristics of flame-retardant bonding, and the flame-retardant grade can reach UL94 V-1. Description of the Drawings

[0011] Figure 1 It is a physical picture of the flexible functional material-2 prepared in Example 1; Figure 2 It is a flame-retardant performance picture of the flexible functional material-2 prepared in Example 1; Figure 3 It is a physical picture of the formaldehyde-free flame-retardant biomass-based adhesives 5-8 prepared in Example 2; Figure 4 It is a physical picture of the formaldehyde-free flame-retardant biomass-based adhesives 9-12 prepared in Example 2; Figure 5 It is a physical picture of the control adhesives 1-3 and the formaldehyde-free flame-retardant biomass-based adhesives 13-14 prepared in Example 3; Figure 6 It is a physical picture of the control adhesives 4-5 and the formaldehyde-free flame-retardant biomass-based adhesives 15-16 prepared in Example 3; Figure 7 It is a physical picture of the non-flexible functional material-2 prepared in Example 3; Figure 8 It is a flame-retardant performance picture of the non-flexible functional material-2 prepared in Example 3. Detailed Embodiments

[0012] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely used to explain the present invention and are not used to limit the present invention.

[0013] It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanations of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0014] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations and / or combinations thereof.

[0015] Example 1: Prepare a formaldehyde-free flame-retardant biomass-based binder-1 containing 10 g of tannic acid, 10 g of poly(adipic acid-1,4-butanediol) diol (PBA), 20 g of polyvinyl alcohol (PVA-210), 100 g of ethanol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the measured bonding shear strength of the bonded wood chips is 1.7 MPa, and the bonding shear strength of the bonded iron sheets is 2.9 MPa. Mix 200 g of leather collagen fibers with 200 g of the above formaldehyde-free flame-retardant biomass-based binder-1 evenly, and then press the mixture into a mold to obtain a flexible functional material-1. After measurement, the flame-retardant grade of the flexible functional material-1 reaches UL94V-0.

[0016] Prepare a formaldehyde-free flame-retardant biomass-based binder-2 containing 20 g of tannic acid, 10 g of poly(adipic acid-1,4-butanediol) diol (PBA), 10 g of polyvinyl alcohol (PVA-210), 100 g of ethanol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the measured bonding shear strength of the bonded wood chips is 1.1 MPa, and the bonding shear strength of the bonded iron sheets is 1.5 MPa. Mix 200 g of leather collagen fibers with 200 g of the above formaldehyde-free flame-retardant biomass-based binder-2 evenly, and then press the mixture into a mold to obtain a flexible functional material-2, as Figure 1 shown. As Figure 2 shown, after measurement, the flame-retardant grade of the flexible functional material-2 reaches UL94 V-0.

[0017] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-3 containing 10 g of tannic acid, 10 g of polyethylene glycol-2000 (PEG-2000), 20 g of polyvinyl alcohol (PVA-210), 100 g of ethanol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 0.7 MPa, and the bonding shear strength of the bonded iron sheets was 1.0 MPa.

[0018] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-4 containing 20 g of tannic acid, 10 g of polyethylene glycol-2000 (PEG-2000), 10 g of polyvinyl alcohol (PVA-210), 100 g of ethanol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 0.5 MPa, and the bonding shear strength of the bonded iron sheets was 0.6 MPa.

[0019] Example 2: As Figure 3 shown: Prepare a formaldehyde-free flame-retardant biomass-based adhesive-5 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 100 g of acetone, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 5.4 MPa, and the bonding shear strength of the bonded iron sheets was 4.0 MPa.

[0020] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-6 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 100 g of pyridine, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 4.2 MPa, and the bonding shear strength of the bonded iron sheets was 0.7 MPa.

[0021] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-7 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 100 g of DMF, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 4.6 MPa, and the bonding shear strength of the bonded iron sheets was 0.8 MPa.

[0022] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-8 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 100 g of isopropanol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 7.0 MPa, and the bonding shear strength of the bonded iron sheets was 7.8 MPa.

[0023] As Figure 4 shown: Prepare a formaldehyde-free flame-retardant biomass-based adhesive-9 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 100 g of methanol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 6.3 MPa, and the bonding shear strength of the bonded iron sheets was 7.2 MPa.

[0024] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-10 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 100 g of ethylene glycol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 0.03 MPa, and the bonding shear strength of the bonded iron sheets was 0.02 MPa.

[0025] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-11 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 100 g of 1, 3-propanediol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 0.04 MPa, and the bonding shear strength of the bonded iron sheets was 0.02 MPa.

[0026] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-12 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 100 g of 1, 2-propanediol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the bonding shear strength of the bonded wood chips was measured to be 0.03 MPa, and the bonding shear strength of the bonded iron sheets was 0.03 MPa.

[0027] Example 3: As Figure 5 shown: Prepare a formaldehyde-free flame-retardant biomass-based adhesive-13 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 53.3 g of ethanol, and 106.7 g of water. After bonding according to the bonding test method of GB / T7124-2008, the measured shear strength of the bonded wood chips is 5.5 MPa, and the shear strength of the bonded iron sheets is 6.5 MPa.

[0028] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-14 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 106.7 g of ethanol, and 53.3 g of water. After bonding according to the bonding test method of GB / T7124-2008, the measured shear strength of the bonded wood chips is 5.8 MPa, and the shear strength of the bonded iron sheets is 7.5 MPa.

[0029] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-15 containing 12 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 105 g of ethanol, and 63 g of water. After bonding according to the bonding test method of GB / T7124-2008, the measured shear strength of the bonded wood chips is 5.7 MPa, and the shear strength of the bonded iron sheets is 7.5 MPa. Mix 200 g of wood fiber with 400 g of the adhesive evenly, and then press the mixture into shape to obtain a non-flexible functional material-1. The measured flexural strength of the non-flexible functional material-1 is 151.1 MPa, and the flame retardant grade reaches UL94 V-1.

[0030] Prepare a formaldehyde-free flame-retardant biomass-based adhesive-16 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), 100 g of ethanol, and 60 g of water. After bonding according to the bonding test method of GB / T7124-2008, the measured shear strength of the bonded wood chips is 6.1 MPa, and the shear strength of the bonded iron sheets is 7.8 MPa. Mix 200 g of wood fiber with 400 g of the adhesive evenly, and then press the mixture into shape to obtain a non-flexible functional material-2, as Figure 7 shown. The measured flexural strength of the non-flexible functional material-2 is 193.3 MPa, as Figure 8 shown, and the flame retardant grade reaches UL94 V-0.

[0031] Prepare a control adhesive-1 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA-210), and 160 g of water. After bonding according to the bonding test method of GB / T7124-2008, the measured shear strength of the bonded wood chips is 0.04 MPa, and the shear strength of the bonded iron sheets is 0.6 MPa.

[0032] Prepare the control adhesive - 2 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA - 210), 40 g of ethanol, and 120 g of water. After bonding according to the bonding test method of GB / T7124 - 2008, the bonding shear strength of the bonded wood chips is measured to be 0.7 MPa, and the bonding shear strength of the bonded iron sheets is 1.8 MPa.

[0033] Prepare the control adhesive - 3 containing 20 g of tannic acid, 20 g of polyvinyl alcohol (PVA - 210), 120 g of ethanol, and 40 g of water. After bonding according to the bonding test method of GB / T7124 - 2008, the bonding shear strength of the bonded wood chips is measured to be 0.03 MPa, and the bonding shear strength of the bonded iron sheets is 0.05 MPa.

[0034] As Figure 6 shown: Prepare the control adhesive - 4 containing 20 g of polyvinyl alcohol (PVA - 210), 112.5 g of ethanol, and 67.5 g of water. After bonding according to the bonding test method of GB / T7124 - 2008, the bonding shear strength of the bonded wood chips is measured to be 1.8 MPa, and the bonding shear strength of the bonded iron sheets is 2.8 MPa. Mix 200 g of wood fibers evenly with 400 g of the adhesive, and then press the mixture into shape to obtain the control non - flexible functional material - 1. The flexural strength of the control non - flexible functional material - 1 is measured to be 56.4 MPa, and it does not have flame retardancy.

[0035] Prepare the control adhesive - 5 containing 4 g of tannic acid, 20 g of polyvinyl alcohol (PVA - 210), 110 g of ethanol, and 66 g of water. After bonding according to the bonding test method of GB / T7124 - 2008, the bonding shear strength of the bonded wood chips is measured to be 5.3 MPa, and the bonding shear strength of the bonded iron sheets is 6.5 MPa. Mix 200 g of wood fibers evenly with 400 g of the adhesive, and then press the mixture into shape to obtain the control non - flexible functional material - 2. The flexural strength of the control non - flexible functional material - 2 is measured to be 90.8 MPa, and the flame retardancy grade reaches UL94 V - HB.

[0036] In summary, the present invention discloses a preparation method and application of an aldehyde - free flame - retardant biomass - based adhesive; belonging to the technical field of adhesives; the aldehyde - free flame - retardant biomass - based adhesive is composed of polyphenols, polyols, and solvents; this aldehyde - free flame - retardant biomass - based adhesive constructs a three - dimensional bonding and flame - retardant network based on high - density secondary bonds, and can be used to bond and prepare flexible and non - flexible functional materials with high flexural strength, zero formaldehyde, and high - efficiency flame retardancy, having good prospects for popularization and application.

[0037] At this point, those skilled in the art will recognize that although the embodiments of the present invention have been shown and described in detail herein, many other variations or modifications that conform to the principles of the present invention can still be directly determined or derived from the disclosed content of the present invention without departing from the spirit and scope of the present invention. Therefore, the scope of the present invention should be understood and determined to cover all such other variations or modifications.

Claims

1. A formaldehyde-free flame-retardant biomass-based adhesive, characterized in that: The formaldehyde-free flame-retardant biomass-based adhesive consists of polyphenol, polyol and solvent.

2. The formaldehyde-free flame-retardant biomass-based adhesive as claimed in claim 1, characterized in that: The polyphenols are plant polyphenols.

3. The formaldehyde-free flame-retardant biomass-based adhesive as claimed in claim 1, characterized in that: The polyol is one or more of PBA, PEG and PVA.

4. The formaldehyde-free flame-retardant biomass-based adhesive as claimed in claim 1, characterized in that: The solvent is a water-organic solvent mixture.

5. The formaldehyde-free flame-retardant biomass-based adhesive as claimed in claim 4, characterized in that: In the water-organic solvent mixture, the organic solvent is one or more of acetone, N,N-dimethylformamide DMF, pyridine, methanol, ethanol, ethylene glycol, isopropanol, 1,2-propylene glycol and 1,3-propylene glycol.

6. The formaldehyde-free flame-retardant biomass-based adhesive according to claim 1, characterized in that: The formaldehyde-free flame-retardant biomass-based adhesive can achieve formaldehyde-free high-performance bonding and flame-retardant bonding of various substrates, and prepare flexible and non-flexible functional materials.

Images