Plant waste-based module soil for facade planting

Abstract

The invention discloses plant waste-based module soil for facade planting, and belongs to the technical field of biomass composite materials, the plant waste-based module soil comprises foaming polyurethane, an antibacterial agent and plant waste; the foamed polyurethane is prepared from a polyol component and an isocyanate component; the antibacterial agent is obtained by carrying out grafting reaction on epoxy quaternary ammonium salt and polyethyleneimine. According to the plant waste-based module soil, foaming polyurethane, an antibacterial agent and plant waste serve as raw materials, a light foaming material of a three-dimensional net structure is formed, the material contains a large number of organic substances and has the performance of being high in water absorption, high in water retention rate and the like, and the plant waste-based module soil is endowed with certain antibacterial property by adding the antibacterial agent; under the condition that the good antibacterial effect is guaranteed, the water absorption and water retention effects of the plant waste-based module soil are improved, and the plant waste-based module soil can be used as an excellent three-dimensional greening integral culture medium.

Description

Technical Field

[0001] The invention belongs to the technical field of biomass composite materials, and in particular relates to a plant waste-based module soil for facade planting. Background Art

[0002] Facade planting refers to planting plants on the facade of a building or other surface of a structure, forming vertical greening by climbing, fixing, sticking or hanging. This form of greening includes balcony planting, vertical gardens, etc., which aims to improve the urban environment and provide aesthetic and ecological benefits. However, the growth space and environment of vertical greening plants are completely different from the ground. The growth matrix needs to have good stability. Considering the load-bearing capacity of the building and the difficulty of maintenance and care of the planting, it also needs to have a large bulk density ratio, good water retention, nutrient slow release and good water permeability and air permeability.

[0003] Natural soil, improved soil with added conditioners, natural minerals, and recycled products of industrial or agricultural organic waste are used as plant cultivation substrates. Although such substrates provide inorganic mineral elements necessary for plant growth, they are easily weathered, have a short duration of fertility, and suffer from severe soil and water loss.

[0004] The patent application with publication number CN110122268A discloses a method for preparing a water-retaining plant cultivation matrix from waste plastics, providing a material with a high water retention rate. However, the preparation process requires foaming after high-temperature melting, which has the disadvantages of complex manufacturing process and low production efficiency. The patent application with publication number CN111226746A discloses a method for preparing a three-dimensional greening matrix and a sponge matrix. By adding stone, soil, peat soil and wood into the sponge matrix, it is easy to destroy the original strength of the sponge and affect the water retention rate of the material, and it is also easy to cause the loss of the cultivation matrix including nutrients. Summary of the invention

[0005] The purpose of the present invention is to provide a plant waste-based module soil for facade planting to solve the problem of poor water retention of facade planting materials.

[0006] The purpose of the present invention can be achieved through the following technical solutions:

[0007] A plant waste-based modular soil for facade planting comprises foamed polyurethane, an antibacterial agent and plant waste; the foamed polyurethane comprises a polyol component and an isocyanate component; the antibacterial agent is obtained by grafting reaction of epoxy quaternary ammonium salt and polyethylene imine.

[0008] Furthermore, the plant waste includes one of fiber straw and mushroom residue.

[0009] Further, it is prepared by the following steps:

[0010] The polyol, foam opening agent, tin catalyst and water are mixed, and the polyol component is obtained after stirring and mixing. The antibacterial agent and plant waste are added to the polyol component, and after being fully mixed, the isocyanate component is added, and after being stirred evenly, the mixture is poured into a mold for foaming to obtain a plant waste-based module soil. The foamed polyurethane includes a polyol component and an isocyanate component. Before the polyol component and the isocyanate component are mixed, that is, before the foaming, the antibacterial agent and the plant waste are added, so that the antibacterial agent and the plant waste are compounded with the polyurethane to form a lightweight foaming material with a three-dimensional network structure.

[0011] Furthermore, the mass ratio of the polyol, foam cell opener, tin catalyst and water in the polyol component is 100:1-1.1:0.3-0.4:3-5; the mass ratio of the polyol, antibacterial agent, plant waste and isocyanate component is 100:7-8:70-80:70.

[0012] Further, the polyol includes at least one of a polyether polyol and a bio-based polyol;

[0013] The isocyanate component includes at least one of 2,4-toluene diisocyanate and diphenylmethane diisocyanate.

[0014] Furthermore, the antibacterial agent is prepared by the following steps:

[0015] Add epoxy quaternary ammonium salt and polyethyleneimine into the solvent, heat to 45-50°C, react for 7-8h, and after the reaction, remove the solvent by rotary evaporation, and then vacuum dry at 50°C to obtain the antibacterial agent.

[0016] Furthermore, the mass ratio of the epoxy quaternary ammonium salt to polyethyleneimine is 2:5.

[0017] Furthermore, the epoxy quaternary ammonium salt is prepared by a nucleophilic addition reaction between a tertiary amine and epichlorohydrin.

[0018] The epoxy quaternary ammonium salt is prepared by the following steps: at a temperature of 40° C., a tertiary amine is added dropwise to epichlorohydrin, the temperature is raised to 80° C. after the addition, and the reaction is continued for 3 hours. After the reaction is completed, the excess epichlorohydrin is removed by vacuum distillation, acetone is added for precipitation, and the epoxy quaternary ammonium salt is obtained after washing and drying.

[0019] Furthermore, the molar ratio of the tertiary amine to epichlorohydrin is 1:4.

[0020] Furthermore, the tertiary amine is one of N,N-dimethylhexylamine, dodecyldimethyl tertiary amine and N,N-dimethyltetradecamine; the long alkyl chain in the tertiary amine is also beneficial to improve the stability and complexity of the cross-linked network and enhance the water retention effect.

[0021] Beneficial effects of the present invention:

[0022] The present invention provides a plant waste-based modular soil for vertical planting. The plant waste-based modular soil uses foamed polyurethane, antibacterial agent and plant waste as raw materials to form a lightweight foam material with a three-dimensional network structure. The material contains a large amount of organic matter and has the properties of strong water absorption and high water retention rate, and can be used as an excellent three-dimensional greening integral cultivation matrix.

[0023] The plant waste and antimicrobial agent added in the present invention are both conducive to improving the water absorption and water retention effect of the plant waste-based module soil, wherein the plant waste can not only improve the water retention effect of the sample, but also can be used as a nutrient for plant growth, providing a better growth environment for plants. However, since it can provide a good environment for plant growth, it will also become a hotbed for the reproduction of bacteria and microorganisms, which is not conducive to the storage of plant waste-based module soil to a certain extent. Therefore, in the present invention, by adding an antimicrobial agent, the plant waste-based module soil is given a certain antibacterial property, and while ensuring its good antibacterial effect, it also has the effect of improving the water absorption and water retention effect of the plant waste-based module soil. DETAILED DESCRIPTION

[0024] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0025] Preparation Example 1

[0026] Preparation of antimicrobial agent:

[0027] At a temperature of 40°C, a tertiary amine is added dropwise to epichlorohydrin, and after the addition, the temperature is raised to 80°C, and the reaction is continued for 3 hours. After the reaction is completed, the excess epichlorohydrin is removed by vacuum distillation, acetone is added for precipitation, and epoxy quaternary ammonium salt is obtained after washing and drying; wherein the molar ratio of the tertiary amine to epichlorohydrin is 1:4, and the tertiary amine is N,N-dimethylhexylamine;

[0028] 2 g of epoxy quaternary ammonium salt and 5 g of polyethyleneimine (25 kDa) were added to 25 mL of methanol, the temperature was raised to 45°C, and the reaction was carried out for 8 hours. After the reaction was completed, the solvent was removed by rotary evaporation, and then vacuum dried at 50°C to obtain an antibacterial agent.

[0029] Preparation Example 2

[0030] Preparation of antimicrobial agent:

[0031] At a temperature of 40°C, a tertiary amine is added dropwise to epichlorohydrin, and after the addition, the temperature is raised to 80°C, and the reaction is continued for 3 hours. After the reaction is completed, the excess epichlorohydrin is removed by vacuum distillation, acetone is added for precipitation, and epoxy quaternary ammonium salt is obtained after washing and drying; the molar ratio of the tertiary amine to epichlorohydrin is 1:4, and the tertiary amine is dodecyl dimethyl tertiary amine;

[0032] 3 g of epoxy quaternary ammonium salt and 5 g of polyethyleneimine (25 kDa) were added to 25 mL of methanol, the temperature was raised to 45°C, and the reaction was carried out for 8 hours. After the reaction was completed, the solvent was removed by rotary evaporation, and then vacuum dried at 50°C to obtain an antibacterial agent.

[0033] Preparation Example 3

[0034] Preparation of antimicrobial agent:

[0035] At a temperature of 40°C, a tertiary amine is added dropwise to epichlorohydrin, and after the addition, the temperature is raised to 80°C, and the reaction is continued for 3 hours. After the reaction is completed, the excess epichlorohydrin is removed by vacuum distillation, acetone is added for precipitation, and an epoxy quaternary ammonium salt is obtained after washing and drying; the molar ratio of the tertiary amine to epichlorohydrin is 1:4, and the tertiary amine is N,N-dimethyltetradecamine;

[0036] 3 g of epoxy quaternary ammonium salt and 5 g of polyethyleneimine (25 kDa) were added to 25 mL of methanol, the temperature was raised to 45°C, and the reaction was carried out for 8 hours. After the reaction was completed, the solvent was removed by rotary evaporation, and then vacuum dried at 50°C to obtain an antibacterial agent.

[0037] Example 1

[0038] This embodiment provides a plant waste-based module soil for facade planting, which is prepared by the following steps:

[0039] 40g of polyether polyol (EP330N), 60g of polypropylene glycol (PPG2000), 1.0g of foam cell opener (H-4002), 0.3g of tin catalyst (dibutyltin dioctanoate) and 3g of water are mixed to obtain a polyol component, 7g of the antibacterial agent prepared in Preparation Example 1 and 70g of mushroom residue are added to the polyol component, and after thorough mixing, an isocyanate component is added, the isocyanate component is obtained by mixing 56g of 2,4-toluene diisocyanate and 14g of diphenylmethane diisocyanate, and after stirring evenly, poured into a mold and foamed at a constant temperature of 80°C for 30min to obtain plant waste-based module soil.

[0040] Example 2

[0041] This embodiment provides a plant waste-based module soil for facade planting, which is prepared by the following steps:

[0042] 40g of polyether polyol (EP330N), 60g of polypropylene glycol (PPG2000), 1.0g of foam cell opener (H-4002), 0.3g of tin catalyst (dibutyltin dioctanoate) and 3g of water are mixed to obtain a polyol component, 7g of the antibacterial agent prepared in Preparation Example 1 and 75g of mushroom residue are added to the polyol component, and after sufficient mixing, an isocyanate component is added. The isocyanate component is obtained by mixing 56g of 2,4-toluene diisocyanate and 14g of diphenylmethane diisocyanate. After stirring evenly, it is poured into a mold and foamed at a constant temperature of 80°C for 30 minutes to obtain plant waste-based module soil.

[0043] Example 3

[0044] This embodiment provides a plant waste-based module soil for facade planting, which is prepared by the following steps:

[0045] 40g of polyether polyol (EP330N), 60g of polypropylene glycol (PPG2000), 1.0g of foam cell opener (H-4002), 0.3g of tin catalyst (dibutyltin dioctanoate) and 3g of water are mixed to obtain a polyol component, 7g of the antibacterial agent prepared in Preparation Example 1 and 80g of mushroom residue are added to the polyol component, and after sufficient mixing, an isocyanate component is added, and the isocyanate component is obtained by mixing 56g of 2,4-toluene diisocyanate and 14g of diphenylmethane diisocyanate. After stirring evenly, it is poured into a mold and foamed at a constant temperature of 80°C for 30 minutes to obtain plant waste-based module soil.

[0046] Example 4

[0047] This embodiment provides a plant waste-based module soil for facade planting, which is prepared by the following steps:

[0048] 40g of polyether polyol (EP330N), 60g of polypropylene glycol (PPG2000), 1.1g of foam cell opener (H-4002), 0.4g of tin catalyst (dibutyltin dioctanoate) and 5g of water are mixed to obtain a polyol component, 8g of the antibacterial agent prepared in Preparation Example 2 and 70g of mushroom residue are added to the polyol component, and after thorough mixing, an isocyanate component is added, the isocyanate component is obtained by mixing 56g of 2,4-toluene diisocyanate and 14g of diphenylmethane diisocyanate, and after stirring evenly, poured into a mold and foamed at a constant temperature of 80°C for 30min to obtain plant waste-based module soil.

[0049] Example 5

[0050] This embodiment provides a plant waste-based module soil for facade planting, which is prepared by the following steps:

[0051] 40g of polyether polyol (EP330N), 60g of polypropylene glycol (PPG2000), 1.0-1.1g of foam cell opener (H-4002), 0.4g of tin catalyst (dibutyltin dioctanoate) and 5g of water are mixed to obtain a polyol component, 8g of the antibacterial agent prepared in Preparation Example 3 and 70g of mushroom residue are added to the polyol component, and after thorough mixing, an isocyanate component is added, the isocyanate component is obtained by mixing 56g of 2,4-toluene diisocyanate and 14g of diphenylmethane diisocyanate, and after stirring evenly, poured into a mold and foamed at a constant temperature of 80°C for 30min to obtain plant waste-based module soil.

[0052] Example 6

[0053] This embodiment provides a plant waste-based module soil for facade planting, which is prepared by the following steps:

[0054] 40g of polyether polyol (EP330N), 60g of polypropylene glycol (PPG2000), 1.0g of foam cell opener (H-4002), 0.3g of tin catalyst (dibutyltin dioctanoate) and 3g of water are mixed to obtain a polyol component, 7g of the antibacterial agent prepared in Preparation Example 3 and 80g of mushroom residue are added to the polyol component, and after thorough mixing, an isocyanate component is added, the isocyanate component is obtained by mixing 56g of 2,4-toluene diisocyanate and 14g of diphenylmethane diisocyanate, and after stirring evenly, poured into a mold and foamed at a constant temperature of 80°C for 30 minutes to obtain plant waste-based module soil.

[0055] The plant waste-based modules prepared in Examples 1 to 6 were tested for bactericidal properties. Staphylococcus aureus and Escherichia coli were used as test bacteria, and the samples were co-cultured with the bacterial solution to test their antibacterial properties. The frozen working bacteria were inoculated into LB broth medium and cultured overnight at 37°C for use. In addition to the bacterial solution, the prepared drugs and required equipment must be sterilized by ultraviolet light in advance, and the operation must be carried out on a clean bench. The bacterial solution concentration was configured to be 1.25×10 5 CFU / mL, per 1cm 2 The sample was mixed with 2 mL of bacterial solution and co-cultured at 37°C for 24 hours, and then the co-cultured bacterial solution was aspirated to measure the absorbance at 600 nm to calculate the sample sterilization rate. The results are shown in Table 1 below:

[0056] Table 1

[0057] project Staphylococcus aureus sterilization rate / % Escherichia coli sterilization rate / % Example 1 99.5 82.2 Example 2 99.3 82.5 Example 3 99.5 82.3 Example 4 99.6 83.1 Example 5 99.5 82.9 Example 6 99.1 82.5

[0058] It can be seen from the test results that the sample prepared by the present invention has a good bactericidal effect on Staphylococcus aureus and Escherichia coli.

[0059] Comparative Example 1

[0060] Compared with Example 1, this comparative example does not add an antibacterial agent, and the remaining raw materials and preparation process remain the same as those of Example 1.

[0061] Comparative Example 2

[0062] Compared with Example 1, the amount of mushroom residue, a plant waste, was increased to 100 g in this comparative example, and the other raw materials and preparation process remained the same as those in Example 1.

[0063] Comparative Example 3

[0064] Compared with Example 1, the amount of mushroom residue, a plant waste, is increased to 100 g in this comparative example, and no antibacterial agent is added. The other raw materials and the preparation process remain the same as those in Example 1.

[0065] The water absorption and water retention of the plant waste-based module soils prepared in Example 1 to Example 6 and Comparative Example 1 to Comparative Example 2 were tested;

[0066] Water absorption rate: Dry to constant weight at 65±5℃, soak the sample of the same weight in water for 50h, take it out until no water drops, weigh the sample and record it as m1; Water absorption rate = (m1-m0) / m0×100%.

[0067] Water retention rate: The weight of the sample after saturation is recorded as m1. The sample after saturation is placed in a blast drying oven with the set temperature at 30℃, 50℃, and 70℃. The mass of the sample after 5 hours is recorded as m n ; Water retention rate = (m1-m n ) / m1×100%;

[0068] The test results are shown in Table 2 below:

[0069] Table 2

[0070] Sample Water absorption / % Water retention rate% Example 1 622 80 Example 2 631 82 Example 3 624 79 Example 4 625 83 Example 5 628 84 Example 6 629 81 Comparative Example 1 550 58 Comparative Example 2 580 70 Comparative Example 3 520 50

[0071] According to the water absorption and water retention test results recorded in Table 2, the introduction of plant waste and antibacterial agent in the present invention promotes the water absorption and water retention of plant waste-based module soil samples. According to the test results of Example 1-Example 3 and Comparative Example 2, the increase in the amount of plant waste promotes the water absorption effect. The fibers of plant waste are interspersed in the pores of polyurethane and tightly combined with them. On the one hand, they can support the pores and improve the strength of the pores. On the other hand, the plant fibers have good hydrophilic and water absorption effects. However, excessive use of plant waste will not continue to improve. Excessive use of plant waste will cause the polyurethane to be unable to completely wrap the excess plant waste, which is not conducive to the formation of pores, and thus cannot exert its water absorption and water retention effects. According to the results of Example 1, Example 4-Example 5 and Comparative Example 1, it can be seen that the addition of an antibacterial agent can improve the water absorption and water retention effects of the sample. The antibacterial agent is obtained by grafting epoxy quaternary ammonium salt and polyethyleneimine, and its structure contains a large number of amino groups, which can be attached to the structure of the polyurethane foam to form chemical bonds, thereby improving the stability of the sample. In the water retention test experiment, in a heated environment, the sample of the embodiment (with the addition of an antibacterial agent) has better water retention performance than the sample of the comparative example (without the addition of an antibacterial agent). The introduced antibacterial agent can form hydrogen bonds with water molecules. Therefore, the sample of the embodiment (with the addition of an antibacterial agent) still has sufficient adsorption capacity for water molecules under heating conditions, thereby having a better water retention effect.

[0072] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0073] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A plant waste-based module soil for facade planting, characterized in that: The invention comprises foamed polyurethane, an antibacterial agent and plant waste; the foamed polyurethane comprises a polyol component and an isocyanate component; and the antibacterial agent is obtained by grafting reaction of epoxy quaternary ammonium salt and polyethylene imine.

2. The plant waste-based module soil for facade planting according to claim 1, characterized in that: The plant waste includes one of fiber straw and mushroom residue.

3. The plant waste-based module soil for facade planting according to claim 1, characterized in that: Prepared by the following steps: The polyol, foam cell opener, tin catalyst and water are mixed and stirred to obtain a polyol component, an antibacterial agent and plant waste are added to the polyol component and mixed thoroughly, and then an isocyanate component is added and stirred evenly, and then poured into a mold for foaming to obtain a plant waste-based module soil.

4. The plant waste-based module soil for facade planting according to any one of claims 1 to 3, characterized in that: The mass ratio of the polyol, foam cell opener, tin catalyst and water in the polyol component is 100:1-1.1:0.3-0.4:3-5; the mass ratio of the polyol, antibacterial agent, plant waste and isocyanate component is 100:7-8:70-80:

70.

5. The plant waste-based module soil for facade planting according to claim 3, characterized in that: The polyol comprises at least one of a polyether polyol and a bio-based polyol; The isocyanate component includes at least one of 2,4-toluene diisocyanate and diphenylmethane diisocyanate.

6. The plant waste-based module soil for facade planting according to claim 1, characterized in that: The antibacterial agent is prepared by the following steps: Add epoxy quaternary ammonium salt and polyethyleneimine into the solvent, heat to 45-50°C, react for 7-8 hours, and after the reaction, remove the solvent by rotary evaporation, and then vacuum dry to obtain the antibacterial agent.

7. The plant waste-based module soil for facade planting according to claim 6, characterized in that: The mass ratio of the epoxy quaternary ammonium salt to polyethyleneimine is 2:

5.

8. The plant waste-based module soil for facade planting according to claim 6, characterized in that: The epoxy quaternary ammonium salt is prepared by a nucleophilic addition reaction between a tertiary amine and epichlorohydrin.

9. The plant waste-based module soil for facade planting according to claim 8, characterized in that: The molar ratio of the tertiary amine to epichlorohydrin is 1:

4.

10. The plant waste-based module soil for facade planting according to claim 8, characterized in that: The tertiary amine is one of N,N-dimethylhexylamine, dodecyldimethyl tertiary amine and N,N-dimethyltetradecamine.