Environment-friendly composite plastic-wood board and preparation method thereof

Abstract

The application relates to the technical field of composite plastic wood, and discloses an environment-friendly composite plastic wood board and a preparation method thereof. The environment-friendly composite plastic wood board comprises the following raw materials: bamboo powder, polybutylene adipate terephthalate, polylactic acid, a compatilizer, a filler, a lubricant, functional fibers and composite additives. The environment-friendly plastic wood board prepared by adding the functional fibers has excellent mechanical properties and antibacterial properties, can avoid being eroded by bacteria and molds, and can avoid the adverse effects of the bacteria and molds on the appearance and properties of the composite plastic wood board. The environment-friendly plastic wood board prepared by adding the composite additives has excellent impact resistance and ultraviolet resistance, can better absorb and disperse energy when being impacted by external force, can avoid being irradiated by ultraviolet rays in a long-term use process, and can avoid the shortening of the service life of the composite plastic wood board.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of composite plastic-wood, in particular to an environment-friendly composite plastic-wood board and a preparation method thereof. BACKGROUND

[0002] The composite plastic-wood board is also called wood-plastic composite board, which has the advantages of wood and plastic. The wood-plastic composite board is prepared by mixing wood as a base material with thermoplastic polymer materials and other processing additives, and then extruding and shaping after heating. The wood-plastic composite board has a long service life and good wear resistance, and can be used to prepare floorings, railings, fences, furniture, pallets, templates, etc., and is applied in many fields such as building, home furnishing, outdoor construction, agriculture, and logistics packaging. The thermoplastic polymer materials commonly used to prepare the wood-plastic composite board include polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polystyrene (PS), etc. However, these polymer materials are petroleum-based materials and are not degradable, which pollutes the ecological environment. Therefore, it is of great practical significance to study the degradable environment-friendly composite plastic-wood board.

[0003] Polybutylene adipate terephthalate (PBAT) has excellent processability and degradability, and can be used as a base material of the composite plastic-wood board. However, polybutylene adipate terephthalate has poor antibacterial performance, which may cause the composite plastic-wood board to be eroded by bacteria and mold, and thus the appearance and performance of the composite plastic-wood board are adversely affected. In addition, polybutylene adipate terephthalate has poor ultraviolet resistance, and long-term exposure to ultraviolet radiation may cause the composite plastic-wood board to fade, crack, and degrade in performance, thereby shortening the service life of the composite plastic-wood board. The patent with publication number CN107987548B discloses a high-strength wood-plastic composite material, which comprises the following raw materials: wood powder, bamboo powder, polyethylene, polyvinyl chloride, starch or modified starch, maleic anhydride grafted polyethylene, lubricant, and antioxidant. The wood-plastic composite material has very good tensile strength and bending strength, and the tensile strength and bending strength are greatly improved after the addition of modified starch. However, the importance of antibacterial performance and ultraviolet resistance is not considered in the wood-plastic composite material. Therefore, the present application provides an environment-friendly composite plastic-wood board, which has degradability, excellent antibacterial performance, ultraviolet resistance, and a long service life. SUMMARY

[0004] In order to solve the problems mentioned in the background, the present application aims to provide an environment-friendly composite plastic-wood board and a preparation method thereof.

[0005] The object of the present application can be achieved by the following technical solutions.

[0006] The environment-friendly composite plastic-wood board comprises the following raw materials in parts by weight: 35-60 parts of bamboo powder, 30-55 parts of polybutylene adipate / terephthalate, 10-16 parts of polylactic acid, 2-5 parts of a compatibilizer, 1-3 parts of a filler, 1-4 parts of a lubricant, 3-6 parts of functional fibers, and 2-5 parts of a composite additive.

[0007] Further, the particle size of the bamboo powder is 100-120 mesh; the compatibilizer is ethylene-methyl acrylate-glycidyl methacrylate; the filler is talc; and the lubricant is zinc stearate.

[0008] Further, the preparation method of the functional fibers comprises the following steps:

[0009] Step A: dispersing wollastonite fibers into dimethyl sulfoxide to form a uniform suspension, adding glyoxylic acid and a catalyst, increasing the temperature to 90-100 DEG C, reacting for 2-4 h, cooling to room temperature, filtering, washing, and drying to obtain modified wollastonite fibers;

[0010] Step B: adding the modified wollastonite fibers into 1,4-dioxane, stirring until uniform, adding amino guanidine hydrochloride and triethylamine, increasing the temperature to 50-60 DEG C, stirring to react for 3-5 h, separating the product, washing, and drying to obtain the functional fibers.

[0011] By using the above technical scheme, the wollastonite is modified by glyoxylic acid, so that aldehyde groups are introduced on the surface of the wollastonite, and the modified wollastonite fibers are obtained; under the action of triethylamine, the aldehyde groups on the surface of the modified wollastonite fibers can react with the amino groups in the structure of the amino guanidine hydrochloride to obtain the functional fibers.

[0012] Further, in Step A, the catalyst is p-toluenesulfonic acid or calcium methylsulfonate.

[0013] Further, the preparation method of the composite additive comprises the following steps:

[0014] Step T1: adding polycaprolactone diol into N,N-dimethylformamide, stirring until uniform, then adding 2,3-dimercaptosuccinic acid, 4-dimethylaminopyridine, and dicyclohexyl carbodiimide, stirring to react for 6-8 h at room temperature, and separating the product to obtain an intermediate material;

[0015] Step T2: adding the intermediate material into dimethyl sulfoxide, mixing until uniform, protecting by nitrogen, adding 4-allyloxy-2-hydroxybenzophenone and a photoinitiator, and irradiating under an ultraviolet lamp with a power of 25-30 W and a wavelength of 365 nm for 45-60 min to separate the product to obtain the composite additive.

[0016] By adopting the technical scheme, the hydroxyl in the polycaprolactone dihydric alcohol structure can be esterified with the carboxyl in the 2,3-dimercaptosuccinic acid structure under the catalysis of 4-dimethylaminopyridine and dicyclohexyl carbodiimide to obtain an intermediate material with a mercapto group, and the mercapto group in the structure of the intermediate material can be subjected to a mercapto alkenyl click reaction with the alkenyl in the 4-allyloxy-2-hydroxybenzophenone structure under the action of ultraviolet lamp irradiation and a photoinitiator to obtain the composite additive.

[0017] Further, in step T1, the polycaprolactone dihydric alcohol has a relative number average molecular weight of 2000.

[0018] Further, in step T2, the photoinitiator is benzoin dimethyl ether or benzoin isopropyl ether.

[0019] A preparation method of an environment-friendly composite plastic-wood board, comprising the following steps:

[0020] Step one: put bamboo powder, polybutylene adipate / terephthalate, polylactic acid, a compatibilizer, a filler, a lubricant, functional fibers and a composite additive into a high-speed mixer, increase the temperature to 80-110 DEG C, set the stirring rate to 350-600 r / min, stir and mix for 35-50 min to obtain a mixture;

[0021] Step two: melt-extrude the mixture into a master batch in a double-screw extruder, heat-press form the master batch into a plate through a flat vulcanizing machine, cut the plate after cooling to obtain the environment-friendly composite plastic-wood board.

[0022] Further, in step two, the heat-press forming temperature is 160-190 DEG C, and the forming pressure is 8-15 MPa.

[0023] The present application has the following advantages:

[0024] (1) The functional fibers prepared by the present application take wollastonite fibers as a matrix, and the wollastonite fibers are modified to solve the problem of easy agglomeration of the wollastonite fibers, effectively improve the compatibility between the wollastonite fibers and the matrix material, and the wollastonite fibers can be uniformly dispersed in the matrix material and firmly combined with the matrix material, so that the wollastonite fibers can fully exert their own advantages to improve the mechanical properties of the composite plastic-wood board, the Schiff base groups and guanidino groups with antibacterial effects are introduced on the surface of the wollastonite fibers through Schiff base reaction, the problem of easy migration and precipitation of small-molecule aminoguanidine hydrochloride antibacterial substances in the matrix material is avoided, the antibacterial properties of the composite plastic-wood board are improved, the erosion of bacteria and mold is avoided, the appearance and properties of the composite plastic-wood board are not adversely affected, and the service life of the composite plastic-wood board is shortened.

[0025] (2) The composite additive prepared by the application contains polycaprolactone diol with good toughness, which can significantly improve the impact resistance of the base material, and the composite additive can cross-link with the base material under the action of the compatibilizer to form a network structure, improve the compactness of the structure, and further improve the impact resistance of the composite plastic-wood board, which can better absorb and disperse energy when subjected to external force, thereby avoiding damage to the base material. In addition, the introduction of benzophenone substances with anti-ultraviolet function effectively improves the anti-ultraviolet performance of the composite plastic-wood board, avoids the composite plastic-wood board from being irradiated by ultraviolet light during long-term use, and avoids discoloration, surface embrittlement, cracking and other problems, thereby shortening the service life.

[0026] Of course, implementing any product of the application does not necessarily require all the advantages described above. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0028] Figure 1 The infrared spectrum of the intermediate material and the composite additive in the application. DETAILED DESCRIPTION

[0029] The technical solutions in the embodiments of the application will be described clearly and completely in the following with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only some embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor are within the protection scope of the application.

[0030] The preparation method of the functional fiber and the composite additive in the following examples and comparative examples is as follows:

[0031] I. Preparation of functional fiber

[0032] Step A: 4.2 g of wollastonite fiber is dispersed in dimethyl sulfoxide to form a uniform suspension, 3 g of glyoxalic acid and 1.4 g of p-toluenesulfonic acid are added, the temperature is raised to 95℃, and after 4 h of reaction, the temperature is cooled to room temperature, filtered, washed, and dried to obtain modified wollastonite fiber;

[0033] Step B: 4 g of modified wollastonite fiber was added into 1,4-dioxane, after stirring evenly, 2.8 g of aminoguanidine hydrochloride and 1.2 g of triethylamine were added, the temperature was raised to 55°C, after stirring for 5 h, the product was separated, washed and dried to obtain the functional fiber.

[0034] The wollastonite fiber and the functional fiber were analyzed by using the Elemental Var i o Micro cube type elemental analyzer, and the results showed that the wollastonite fiber did not contain nitrogen element, and the percentage content of nitrogen element in the functional fiber was 5.23%, so it was known that the aminoguanidine hydrochloride was successfully grafted onto the surface of the wollastonite fiber to provide a nitrogen source.

[0035] II. Preparation of composite additive

[0036] Step T1: 2 g of polycaprolactone diol with a relative number average molecular weight of 2000 was added into N,N-dimethylformamide, after stirring evenly, 0.6 g of 2,3-dimercaptosuccinic acid, 0.1 g of 4-dimethylaminopyridine and 0.2 g of dicyclohexyl carbodiimide were added, after stirring at room temperature for 6 h, the product was separated to obtain an intermediate material;

[0037] Step T2: 1.6 g of the intermediate material was added into dimethyl sulfoxide, after mixing evenly, nitrogen protection was carried out, 0.5 g of 4-allyloxy-2-hydroxybenzophenone and 0.1 g of benzoin dimethyl ether were added, after reaction under the irradiation of an ultraviolet lamp with a power of 25 W and a wavelength of 365 nm for 50 min, the product was separated to obtain the composite additive.

[0038] The intermediate material and the composite additive were subjected to infrared test by using a Fourier infrared spectrometer, as shown in Figure 1 , it was known from the analysis that in the infrared spectrum of the intermediate material, S-H absorption peaks appeared at 2561 cm -1 and 2538 cm -1 , ester group C=O absorption peak appeared at 1736 cm -1 , in the infrared spectrum of the composite additive, O-H absorption peak appeared at 3412 cm -1 , C-H absorption peak in the benzene ring appeared at 3032 cm -1 , S-H absorption peak disappeared at 2561 cm -1 , and C-O-C absorption peak appeared at 1238 cm -1 .

[0039] Example 1

[0040] Preparation of environment-friendly composite plastic-wood board

[0041] Step one: 35g of bamboo powder with a particle size of 120 mesh, 30g of polybutylene adipate terephthalate, 10g of polylactic acid, 2g of ethylene-methyl acrylate-glycidyl methacrylate, 1g of talcum powder, 1g of zinc stearate, 3g of functional fiber, 2g of composite additive were added into a high-speed mixer, the temperature was raised to 80℃, the stirring rate was set to 350r / min, and after stirring and mixing for 35min, a mixture was obtained;

[0042] Step two: the mixture was put into a double screw extruder to melt and extrude the masterbatch, the masterbatch was passed through a flat vulcanizing machine and hot pressed, the molding temperature was 160℃, the molding pressure was 10MPa, and after cooling, cutting treatment was performed, and an environmentally friendly composite plastic-wood board was obtained.

[0043] Example 2

[0044] Preparation of environmentally friendly composite plastic-wood board

[0045] Step one: 45g of bamboo powder with a particle size of 120 mesh, 40g of polybutylene adipate terephthalate, 12g of polylactic acid, 3g of ethylene-methyl acrylate-glycidyl methacrylate, 1g of talcum powder, 2g of zinc stearate, 4g of functional fiber, 3g of composite additive were added into a high-speed mixer, the temperature was raised to 90℃, the stirring rate was set to 450r / min, and after stirring and mixing for 40min, a mixture was obtained;

[0046] Step two: the mixture was put into a double screw extruder to melt and extrude the masterbatch, the masterbatch was passed through a flat vulcanizing machine and hot pressed, the molding temperature was 170℃, the molding pressure was 12MPa, and after cooling, cutting treatment was performed, and an environmentally friendly composite plastic-wood board was obtained.

[0047] Example 3

[0048] Preparation of environmentally friendly composite plastic-wood board

[0049] Step one: 55g of bamboo powder with a particle size of 100 mesh, 50g of polybutylene adipate terephthalate, 14g of polylactic acid, 4g of ethylene-methyl acrylate-glycidyl methacrylate, 2g of talcum powder, 3g of zinc stearate, 5g of functional fiber, 4g of composite additive were added into a high-speed mixer, the temperature was raised to 100℃, the stirring rate was set to 550r / min, and after stirring and mixing for 45min, a mixture was obtained;

[0050] Step two: the mixture was put into a double screw extruder to melt and extrude the masterbatch, the masterbatch was passed through a flat vulcanizing machine and hot pressed, the molding temperature was 180℃, the molding pressure was 14MPa, and after cooling, cutting treatment was performed, and an environmentally friendly composite plastic-wood board was obtained.

[0051] Example 4

[0052] Preparation of environment-friendly composite plastic-wood board

[0053] Step one: 60g of bamboo powder with a particle size of 100 mesh, 55g of polybutylene adipate terephthalate, 16g of polylactic acid, 5g of ethylene-methyl acrylate-glycidyl methacrylate, 3g of talcum powder, 4g of zinc stearate, 6g of functional fiber, and 5g of composite additives were added into a high-speed mixer, the temperature was raised to 110℃, the stirring rate was set to 600r / min, and after stirring and mixing for 50min, a mixture was obtained;

[0054] Step two: the mixture was placed into a double-screw extruder to melt and extrude masterbatch, the masterbatch was subjected to hot pressing molding through a flat vulcanizing machine, the molding temperature was 190℃, the molding pressure was 15MPa, and after cooling, cutting treatment was performed, and an environment-friendly composite plastic-wood board was obtained.

[0055] Comparative example 1

[0056] Preparation of environment-friendly composite plastic-wood board

[0057] Step one: 55g of bamboo powder with a particle size of 100 mesh, 50g of polybutylene adipate terephthalate, 14g of polylactic acid, 4g of ethylene-methyl acrylate-glycidyl methacrylate, 2g of talcum powder, 3g of zinc stearate, and 5g of functional fiber were added into a high-speed mixer, the temperature was raised to 100℃, the stirring rate was set to 550r / min, and after stirring and mixing for 45min, a mixture was obtained;

[0058] Step two: the mixture was placed into a double-screw extruder to melt and extrude masterbatch, the masterbatch was subjected to hot pressing molding through a flat vulcanizing machine, the molding temperature was 180℃, the molding pressure was 14MPa, and after cooling, cutting treatment was performed, and an environment-friendly composite plastic-wood board was obtained.

[0059] Comparative example 2

[0060] Preparation of environment-friendly composite plastic-wood board

[0061] Step one: 55g of bamboo powder with a particle size of 100 mesh, 50g of polybutylene adipate terephthalate, 14g of polylactic acid, 4g of ethylene-methyl acrylate-glycidyl methacrylate, 2g of talcum powder, 3g of zinc stearate, and 4g of composite additives were added into a high-speed mixer, the temperature was raised to 100℃, the stirring rate was set to 550r / min, and after stirring and mixing for 45min, a mixture was obtained;

[0062] Step two: put the mixed materials into a double screw extruder to melt and extrude the master batch, the master batch is hot-pressed into a shape by a flat vulcanizing machine, the molding temperature is 180℃, the molding pressure is 14MPa, after cooling, cutting treatment is carried out, and the environment-friendly composite plastic-wood board is obtained.

[0063] Comparative example 3

[0064] Preparation of the environment-friendly composite plastic-wood board

[0065] Step one: put 55g of bamboo powder with a particle size of 100 mesh, 50g of polybutylene adipate terephthalate, 14g of polylactic acid, 4g of ethylene-methyl acrylate-glycidyl methacrylate, 2g of talc powder, 3g of zinc stearate, 5g of wollastonite fiber, and 4g of composite additives into a high-speed mixer, increase the temperature to 100℃, set the stirring rate to 550r / min, stir and mix for 45min, and obtain the mixed materials;

[0066] Step two: put the mixed materials into a double screw extruder to melt and extrude the master batch, the master batch is hot-pressed into a shape by a flat vulcanizing machine, the molding temperature is 180℃, the molding pressure is 14MPa, after cooling, cutting treatment is carried out, and the environment-friendly composite plastic-wood board is obtained.

[0067] Comparative example 4

[0068] Preparation of the environment-friendly composite plastic-wood board

[0069] Step one: put 55g of bamboo powder with a particle size of 100 mesh, 50g of polybutylene adipate terephthalate, 14g of polylactic acid, 4g of ethylene-methyl acrylate-glycidyl methacrylate, 2g of talc powder, 3g of zinc stearate, 5g of functional fiber, and 4g of 4-allyloxy-2-hydroxybenzophenone into a high-speed mixer, increase the temperature to 100℃, set the stirring rate to 550r / min, stir and mix for 45min, and obtain the mixed materials;

[0070] Step two: put the mixed materials into a double screw extruder to melt and extrude the master batch, the master batch is hot-pressed into a shape by a flat vulcanizing machine, the molding temperature is 180℃, the molding pressure is 14MPa, after cooling, cutting treatment is carried out, and the environment-friendly composite plastic-wood board is obtained.

[0071] Performance detection

[0072] The environmentally friendly composite plastic-wood board prepared in Examples 1-4 and Comparative Examples 1-4 was made into samples conforming to the test standards, the tensile strength of the samples was tested according to the standard GB / T 1040.1-2018, the impact strength of the samples was tested according to the standard GB / T 1843-2008, the samples were placed for 60 days, then placed under the UVB-313 type ultraviolet fluorescent lamp tube for irradiation aging for 800h, then the color difference ΔE was calculated according to the formula ΔE=[(△L) 2 +(△a) 2 +(△b) 2 ] 1 / 2 The larger the value of ΔE, the worse the anti-ultraviolet performance and the more serious the aging. The antibacterial rate of the samples was tested according to the antibacterial test in the standard JC / T 2039-2010, and the test results are shown in the following table:

[0073]

[0074] As shown in the above table, the environmentally friendly composite plastic-wood board prepared in Examples 1-4 has excellent mechanical properties, impact resistance, antibacterial properties and anti-ultraviolet properties. Comparative Example 1 added functional fibers without adding composite additives, and has excellent mechanical properties and antibacterial properties, but poor impact resistance and anti-ultraviolet properties. Comparative Example 2 added composite additives without adding functional fibers, and has excellent impact resistance and anti-ultraviolet properties, but poor mechanical properties and antibacterial properties. Comparative Example 3 added wollastonite fibers and composite additives, and the wollastonite fibers were directly added without modification, which easily caused agglomeration, and had poor effect on improving mechanical properties. The antibacterial substance was not introduced, so the antibacterial properties were poor, and the impact resistance and anti-ultraviolet properties were excellent. Comparative Example 4 added functional fibers and 4-allyloxy-2-hydroxybenzophenone, and had excellent mechanical properties and antibacterial properties. However, 4-allyloxy-2-hydroxybenzophenone is a small molecule anti-ultraviolet substance, which has a migration and precipitation phenomenon, so the anti-ultraviolet properties are poor. Moreover, the poly-caprolactone diol cannot be cross-linked with the matrix to form a network structure to improve the impact resistance, so the impact resistance is poor.

[0075] The above content is only an example and description of the concept of the present application. Those skilled in the art can make various modifications or supplements to the described specific embodiments or use similar ways to replace them, as long as they do not deviate from the concept of the present application or exceed the scope defined by the present claims.

Claims

1. An environmentally friendly composite plastic-wood board, characterized in that, The raw materials include the following components by weight: 35-60 parts of bamboo powder, 30-55 parts of polybutylene adipate / terephthalate, 10-16 parts of polylactic acid, 2-5 parts of a compatibilizer, 1-3 parts of a filler, 1-4 parts of a lubricant, 3-6 parts of a functional fiber, and 2-5 parts of a composite additive; The preparation method of the functional fiber comprises the following steps: Step A: dispersing wollastonite fibers into dimethyl sulfoxide to form a uniform suspension, adding glyoxalic acid and a catalyst, increasing the temperature to 90-100 DEG C, reacting for 2-4 h, cooling to room temperature, and then performing suction filtration, washing, and drying to obtain modified wollastonite fibers; Step B: adding the modified wollastonite fibers into 1, 4-dioxane, stirring until uniform, adding aminoguanidine hydrochloride and triethylamine, increasing the temperature to 50-60 DEG C, stirring for 3-5 h, and then separating the product, washing, and drying to obtain the functional fiber; The preparation method of the composite additive comprises the following steps: Step T1: adding polycaprolactone diol into N, N-dimethylformamide, stirring until uniform, and then adding 2, 3-dimercaptosuccinic acid, 4-dimethylaminopyridine, and dicyclohexyl carbodiimide, stirring at room temperature for 6-8 h, and then separating the product to obtain an intermediate material; Step T2: adding the intermediate material into dimethyl sulfoxide, mixing until uniform, and then introducing nitrogen protection, adding 4-allyloxy-2-hydroxybenzophenone and a photoinitiator, and then irradiating under an ultraviolet lamp with a power of 25-30 W and a wavelength of 365 nm for 45-60 min to separate the product to obtain the composite additive.

2. The environment-friendly composite plastic-wood board according to claim 1, characterized in that, The particle size of the bamboo powder is 100-120 mesh; the compatibilizer is ethylene-methyl acrylate-glycidyl methacrylate; the filler is talc; and the lubricant is zinc stearate.

3. The environment-friendly composite plastic-wood board according to claim 1, characterized in that, In step A, the catalyst is p-toluenesulfonic acid or calcium methylsulfonate.

4. The environment-friendly composite plastic-wood board according to claim 1, characterized in that, In step T1, the relative number-average molecular mass of the polycaprolactone diol is 2000.

5. The environment-friendly composite plastic-wood board according to claim 1, characterized in that, In step T2, the photoinitiator is benzoin dimethyl ether or benzoin isopropyl ether.

6. The method for preparing the environment-friendly composite plastic-wood board of claim 1, characterized in that, The method comprises the following steps: Step one: adding bamboo powder, polybutylene adipate / terephthalate, polylactic acid, a compatibilizer, a filler, a lubricant, a functional fiber, and a composite additive into a high-speed mixer, increasing the temperature to 80-110 DEG C, setting the stirring rate to 350-600 r / min, and then stirring and mixing for 35-50 min to obtain a mixture; Step two: melting and extruding the mixture into a master batch in a double-screw extruder, hot-pressing the master batch into a plate vulcanizing machine, and then cutting the master batch after cooling to obtain an environmentally-friendly composite plastic-wood board.

7. The preparation method of the environment-friendly composite plastic-wood board according to claim 6, characterized in that, In step two, the hot-pressing temperature is 160-190 DEG C, and the molding pressure is 8-15 MPa.

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