CN114958022A

CN114958022A - Anti-aging wood-plastic composite material for wood-like furniture and preparation method thereof

Info

Publication number: CN114958022A
Application number: CN202210163019.2A
Authority: CN
Inventors: 陈光杰; 蒋鹏; 方英雄
Original assignee: Guangzhou Yuanrui Furniture Industrial Co ltd
Current assignee: Guangzhou Yuanrui Furniture Industrial Co ltd
Priority date: 2022-02-22
Filing date: 2022-02-22
Publication date: 2022-08-30

Abstract

The application relates to an anti-aging wood-plastic composite material for wood-like furniture and a preparation method thereof, wherein the composite material comprises the following raw materials in parts by mass: 100 portions and 150 portions of polypropylene; 300 portions of modified wood powder and 400 portions of modified wood powder; 10-12 parts of a silane coupling agent; 5-7 parts of a foaming agent; 12-15 parts of a stabilizer; and 5-8 parts of a lubricant. The preparation method comprises the following steps: step one, uniformly mixing polypropylene, a stabilizer, a lubricant and a foaming agent at 50-60 ℃ to obtain a mixture; step two, adding the modified wood powder and the silane coupling agent into the mixture, and uniformly mixing at 70-80 ℃ to obtain a premix; and step three, melting, plasticizing and extruding the premix to obtain the anti-aging wood-plastic composite material for the wood-like furniture. The application has the effects of improving the strength performance of the wood-plastic composite material and guaranteeing the aging resistance of the wood-plastic composite material.

Description

Anti-aging wood-plastic composite material for wood-like furniture and preparation method thereof

Technical Field

The application relates to the technical field of composite materials, in particular to an anti-aging wood-plastic composite material for wood-like furniture and a preparation method thereof.

Background

At present, various countries in the world carry out all-round treatment on various waste plastic pollution, and certain effect is achieved, wherein wood powder or plant fiber is used for filling, and the wood powder or plant fiber is extruded, pressed or injection molded by special equipment, so that a plastic wood product which can be used for replacing a wood product in some occasions is particularly practical, and a wood-plastic composite (WPC) is produced at the same time. The wood-plastic composite (WPC) is a novel green environment-friendly composite material prepared by reinforcing and filling thermoplastic plastics by using low-cost natural plant fibers or powder materials such as wood, straw scales, bamboo and the like, and the development and research of the wood powder and waste plastic composite can not only provide opportunities for fully utilizing natural resources, but also reduce the environmental pollution caused by waste plastics. The WPC can be widely applied to the fields of outdoor buildings, garden landscapes, automobile industry, packaging transportation, storage and the like. Although the aging resistance of the WPC is relatively excellent compared to natural materials such as wood and bamboo. However, the aging phenomena of surface fading, fragmentation, cracking, mildew and the like of the wood-plastic composite material for the wood-like furniture are still great problems in the long-term use process, and the good and bad aging resistance of the WPC plays a crucial role in continuously maintaining rapid development and expanding the application range in the future.

In the process of researching the aging resistance of the WPC, the inventor finds that the wood powder and the high molecular compound are poor in compatibility in the preparation process of the wood-plastic composite material, so that the wood powder cannot be uniformly dispersed when mixed, the bonding strength between the wood powder and the high molecular compound is weakened due to the problem, external water molecules, oxygen, fungi and the like easily penetrate into the composite material from the weak connection position between the wood powder and the high molecular compound, the oxidation decomposition is caused, and the strength and the aging resistance of the wood-plastic composite material are greatly reduced.

In order to solve the problems, the inventor considers that the key for ensuring the aging resistance of the wood-plastic composite material is to enhance the bonding strength between the wood powder and the high molecular compound and stabilize the mechanical property of the composite material.

Disclosure of Invention

In order to improve the strength performance of the wood-plastic composite material and ensure the aging resistance of the wood-plastic composite material, the application provides an aging-resistant wood-plastic composite material for wood-like furniture and a preparation method thereof.

In a first aspect, the application provides an aging-resistant wood-plastic composite material for wood-like furniture, which adopts the following technical scheme:

an anti-aging wood-plastic composite material for wood-like furniture comprises the following raw materials in parts by mass:

100 portions and 150 portions of polypropylene;

300 portions of modified wood powder and 400 portions of modified wood powder;

10-12 parts of a silane coupling agent;

5-7 parts of a foaming agent;

12-15 parts of a stabilizer;

5-8 parts of a lubricant;

the preparation method of the modified wood flour comprises the following steps:

s1, alkaline washing: soaking 800 parts by mass of wood flour in 5-7% sodium hydroxide solution for 1-2h, taking out the wood flour, washing and drying to obtain alkali-washed wood flour;

s2, surface modification: uniformly mixing alkaline washing wood flour with 30-40 parts of dibutyl phthalate, 80-100 parts of epoxy resin and 20-30 parts of 1-vinyl-2-pyrrolidone at 60-70 ℃, washing and drying to obtain modified wood flour;

s3, shaping: mixing and ball-milling the modified wood flour and triethanolamine with the mass of 0.3 percent of the wood flour, and screening to obtain the 120-mesh modified wood flour with the average grain diameter of 100-.

The main component of the wood flour is cellulose, the cellulose contains a large amount of hydroxyl, and the hydroxyl forms intermolecular hydrogen bonds or intramolecular hydrogen bonds, so that the wood flour has water absorbability and strong polarity, and the polypropylene is nonpolar and has hydrophobicity, so that the compatibility between the wood flour and the polypropylene is poor, and the adhesive force of an interface is small; furthermore, wood flour with high loading is poor in dispersion effect in molten polypropylene and often exists in a certain aggregated state, so that melt flowability is poor and extrusion molding processing is difficult. In order to prepare the wood-plastic composite material with excellent performance, firstly, the good adhesion of the interface between the wood powder and the polypropylene is ensured, and the factors influencing the interface adhesion strength of the wood powder and the polypropylene are mainly 2, namely whether the chemical bonding effect is formed at the interface or not and whether the chemical bonding effect is related to the surface form of the wood powder.

The surface of the wood flour often adsorbs some dust impurities, and the wood flour contains small molecular compounds. During the mixing process, these small molecular substances may exude to the surface of wood flour, thereby forming a weak boundary layer at the interface and weakening the interface interaction. According to the technical scheme, the wood flour is firstly subjected to alkalization treatment, so that impurities can be consumed by NaOH or leached, and the influence of a weak boundary layer is reduced; the flexural properties of wood flour are mainly provided by lignin and hemicellulose, while the tensile strength is mainly contributed by cellulose. Proper alkalization treatment can dissolve lignin and hemicellulose in the outer layer of the cellulose, so that the bending property of the wood flour is reduced, and the effective contact area between the cellulose and the polypropylene matrix can be increased; part of the lignin and hemicellulose is dissolved in the alkalization treatment, and more pits appear on the surface and in the interior of the wood flour. The surface of the alkalized wood powder is modified, and the dibutyl phthalate, the epoxy resin and the 1-vinyl-2-pyrrolidone are subjected to synergistic effect to be diffused and filled into pits on the surface and inside the wood powder, so that a surface substance with stronger plasticity and cohesiveness is formed on the surface of the wood powder, and a stronger adhesive effect can be formed at the interface of the wood powder and the polypropylene when the surface substance is mixed and dissolved, so that the interface cohesive force of the wood powder and the polypropylene is favorably improved. And further through ball milling wood flour, wood flour changes spherical or approximately spherical particle under the friction crushing effect of mutual collision, the mobility and the dispersibility of wood flour are improved, the ball milling process is favorable for further bonding between the wood flour and the surface layer, and further favorable for fully mixing and bonding between the wood flour and polypropylene.

The modified wood flour obtained by the treatment has good dispersibility, in the process of mixing with polypropylene, the surface quality of the uniformly dispersed modified wood flour particles can be crosslinked and entangled with the polypropylene matrix, and a strong bonding layer is formed on the interface of the wood flour and the polypropylene matrix under the promotion of a silane coupling agent, so that the interface bonding force of the wood flour and the polypropylene matrix is greatly improved; the wood powder and the polypropylene interface are tightly bonded, so that external water, oxygen, bacteria and the like are difficult to permeate into the interface of the wood powder and the polypropylene, the mechanical property of the wood-plastic composite material is improved, and the aging resistance of the wood-plastic composite material is ensured.

Preferably, the modified wood flour is selected from two or more of sawdust, corn straw powder, coconut shell powder, nut shell powder and eucalyptus wood flour.

By adopting the technical scheme, the corn straw powder has better adhesiveness and plasticity after being changed into paste from powder; the coconut shell powder has excellent mildew-proof and isolating performance; the nut shell powder mainly comprises cellulose, hemicellulose and lignin, and the lignin has the highest mass fraction and has the characteristics of toughness, wear resistance, pressure resistance, stable chemical performance and strong adsorbability; the eucalyptus wood powder has good flexibility; the wood powder is mixed and can be well matched with each other, so that the mixed wood powder has good wood processability and plasticity, good modification performance can be obtained in the modification process, and the wood-plastic composite material is fully combined with polypropylene when being mixed and dissolved, and has stable mechanical property and aging resistance.

Preferably, the lubricant is prepared by mixing zinc stearate, vinyl distearamide and polydimethylsiloxane according to the mass ratio of (1-1.2) to (1-1.5) to (0.5-0.7).

By adopting the technical scheme, the lubricant prepared by compounding the zinc stearate, the vinyl distearamide and the polydimethylsiloxane according to a certain proportion range is beneficial to improving the compatibility between the polypropylene matrix and the modified wood flour, so that the polypropylene matrix can be fully mixed with the modified wood flour, the melt viscosity of the polypropylene matrix is reduced, and the melt flowability of the polypropylene matrix is improved; in the mixing and dissolving process, the three components and the surface layer on the surface of the modified wood powder particles can be mutually blended, so that the permeation and bonding effect of the components in the surface layer on the polypropylene matrix is enhanced, the interface bonding strength of the polypropylene matrix and the modified wood powder is further enhanced, and the mechanical property and the aging resistance of the wood-plastic composite material are further improved.

Preferably, the feed also comprises the following raw materials in parts by mass: 1-3 parts of zinc borate and 0.5-0.8 part of nano mica powder.

By adopting the technical scheme, the zinc borate can play a role in insect prevention and antibiosis; the zinc borate and the nano mica powder have a mixing effect, have high fluidity and can generate a bonding effect with macromolecules, so that the fluidity of the modified wood powder can be improved, and the compatibility between the modified wood powder and a polypropylene matrix can be improved, so that the interface bonding strength between the modified wood powder and the polypropylene matrix can be enhanced, and the mechanical property and the aging resistance of the wood-plastic composite material can be improved.

Preferably, the stabilizer is one of calcium zinc stabilizers CH400, CH401 and CH 402.

By adopting the technical scheme, the calcium-zinc stabilizer has excellent thermal stability, can be matched with the lubricant to endow the modified wood flour with good dispersibility, and enhances the wrapping with the polypropylene matrix; the calcium-zinc stabilizer can promote melting in the process of melting and homogenizing the mixture, deepens the crosslinking entanglement between the surface quality of the modified wood powder particles and the polypropylene matrix, makes the mixture uniformly plasticized, and improves the stability of the mechanical property and the aging resistance of the wood-plastic composite material.

In a second aspect, the application provides a preparation method of an anti-aging wood-plastic composite material for wood-like furniture, which adopts the following technical scheme:

a preparation method of an anti-aging wood-plastic composite material for wood-like furniture comprises the following steps:

step one, uniformly mixing polypropylene, a stabilizer, a lubricant and a foaming agent at 50-60 ℃ to obtain a mixture;

step two, adding the modified wood powder and the silane coupling agent into the mixture, and uniformly mixing at 70-80 ℃ to obtain a premix;

and step three, melting, plasticizing and extruding the premix to obtain the anti-aging wood-plastic composite material for the wood-like furniture.

Preferably, in the second step, the modified wood powder and the silane coupling agent are added into the mixture and stirred for 10-15min, and then 1-3 parts by mass of zinc borate and 0.5-0.8 part by mass of nano mica powder are added and stirred for 10-15 min.

Preferably, in the second step, the zinc borate and the nano mica powder are uniformly mixed and then added into the mixture.

By adopting the technical scheme, the polypropylene, the stabilizer, the lubricant and the foaming agent are mixed firstly, so that the stabilizer, the lubricant and the foaming agent can be uniformly mixed with the polypropylene and can fully play a role when being mixed and dissolved conveniently, the modified wood and the silane coupling agent are added later, the interfacial resistance among the stabilizer, the lubricant and the foaming agent and the modified wood powder is reduced, the uniform dispersion of the modified wood powder is facilitated, and the zinc borate and the nano mica powder are added finally, so that the dispersion barrier of the zinc borate and the nano mica powder to other substances in the components is reduced; by adopting the operation, the components can be uniformly dispersed and fully mixed, so that the mixture can be uniformly plasticized when mixed and melted, and the overall good performance of the wood-plastic composite material is ensured.

In summary, the present application includes at least one of the following beneficial technical effects:

1. according to the application, wood flour is modified, the modified wood flour obtained through treatment has good fluidity and dispersibility, and can be uniformly dispersed in the process of mixing with polypropylene, the surface quality of the particle surface of the modified wood flour can be crosslinked and entangled with a polypropylene matrix when being mixed, and a strong bonding layer is formed on the interface of the wood flour and the polypropylene matrix under the promotion of a silane coupling agent, so that the interface bonding force of the wood flour and the polypropylene matrix is greatly improved; the wood powder and the polypropylene interface are tightly bonded, so that external water, oxygen, bacteria and the like are difficult to permeate into the interface of the wood powder and the polypropylene, the mechanical property of the wood-plastic composite material is improved, and the aging resistance of the wood-plastic composite material is ensured;

2. according to the application, the lubricant is prepared by compounding zinc stearate, vinyl distearamide and polydimethylsiloxane according to a certain proportion range, so that the compatibility between the polypropylene matrix and the modified wood flour is improved, and the polypropylene matrix can be fully mixed with the modified wood flour; in the mixing and dissolving process, the three materials and the surface layer on the surface of the modified wood powder particles can be mutually blended, so that the permeation and bonding effects of the components in the surface layer on the polypropylene matrix are enhanced, the interface bonding strength of the polypropylene matrix and the modified wood powder is further enhanced, and the mechanical property and the aging resistance of the wood-plastic composite material are further improved;

3. according to the application, the mixing effect of the zinc borate and the nano mica powder is added, the flowability of the modified wood powder can be improved, and the compatibility between the modified wood powder and the polypropylene matrix can be improved, so that the interface bonding strength between the modified wood powder and the polypropylene matrix is enhanced, the mechanical property and the aging resistance of the wood-plastic composite material are improved, in addition, the zinc borate and the nano mica powder on the outer surface of the mixture act synergistically, a covering layer is formed on the surface of the mixture at high temperature, the covering layer can inhibit the oxidation reaction and the thermal decomposition effect of components in the mixture, the stability of the mechanical property and the aging resistance of the composite material is improved, and the surface of the prepared wood-plastic composite material is smooth and wear-resistant.

Detailed Description

The present application will be described in further detail with reference to examples.

The information on the source of the raw materials used in the following preparation examples, examples and comparative examples is detailed in table 1.

TABLE 1

Preparation example

Preparation example 1

The preparation example discloses a preparation method of modified wood powder, which specifically comprises the following steps:

s1, alkaline washing: soaking 800kg of sawdust in 1000kg of 5% sodium hydroxide solution for 25min, taking out the sawdust, washing away excessive sodium hydroxide in the sawdust with clear water, drying in an oven with circulating air at 80 ℃ for 24h, stirring the sawdust properly every 3h, and drying to obtain alkaline washing wood powder;

s2, surface modification: placing alkaline washed wood flour, 30kg of dibutyl phthalate, 80kg of epoxy resin and 20kg of 1-vinyl-2-pyrrolidone into a high-speed mixer, stirring for 10min at the temperature of 70 ℃ and the rotating speed of 3200r/min, washing once with clear water after stirring, then placing into an oven with circulating air, drying for 24h at the temperature of 60 ℃, properly stirring the wood flour every 3h, and drying to obtain modified wood flour;

s3, shaping: and putting the modified wood flour and 2.4kg of triethanolamine into a ball mill, mixing and ball-milling the modified wood flour and the triethanolamine at the normal temperature and the rotating speed of 80r/min for 30min, and carrying out vibration screening on the ball-milled wood flour to obtain the modified wood flour with the average particle size of 100-120 meshes.

Preparation example 2

s1, alkaline washing:

s1-1, mixing 400kg of corn straw powder and 400kg of coconut shell powder, adding into a ball mill, and mixing and ball-milling for 15min at normal temperature and at the rotating speed of 45r/min to obtain a wood powder mixture;

s1-2, soaking the wood flour mixture in 1000kg of 7% sodium hydroxide solution for 25min, taking out the wood flour, washing away excessive sodium hydroxide in the wood flour with clear water, drying for 24h in an oven with circulating air at 80 ℃, properly stirring the wood flour every 3h, and drying to obtain alkali-washed wood flour;

s2, surface modification: placing alkaline washed wood flour, 40kg of dibutyl phthalate, 100kg of epoxy resin and 30kg of 1-vinyl-2-pyrrolidone into a high-speed mixer, stirring for 10min at the temperature of 70 ℃ and the rotating speed of 3600r/min, washing once with clear water after stirring, then placing into an oven with circulating air, drying for 24h at the temperature of 60 ℃, properly stirring the wood flour every 3h, and drying to obtain modified wood flour;

s3, shaping: and putting the modified wood flour and 2.4kg of triethanolamine into a ball mill, mixing and ball-milling the modified wood flour and the triethanolamine at the normal temperature and the rotating speed of 100r/min for 30min, and carrying out vibration screening on the ball-milled wood flour to obtain the modified wood flour with the average particle size of 100-120 meshes.

Preparation example 3

s1, alkaline washing:

s1-1, mixing 200kg of sawdust, 80kg of corn straw powder, 120kg of coconut shell powder, 100kg of nut shell powder and 300kg of eucalyptus powder, adding into a ball mill, and mixing and ball-milling at the normal temperature and the rotating speed of 45r/min for 15min to obtain a wood powder mixture;

s1-2, soaking the wood flour mixture in 1000kg of 6% sodium hydroxide solution for 25min, taking out the wood flour, washing away excessive sodium hydroxide in the wood flour with clear water, drying for 24h in an oven with circulating air at 80 ℃, properly stirring the wood flour every 3h, and drying to obtain alkali-washed wood flour;

s2, surface modification: putting alkali-washed wood flour, 35kg of dibutyl phthalate, 90kg of epoxy resin and 25kg of 1-vinyl-2-pyrrolidone into a high-speed mixer, stirring for 10min at 65 ℃ and 3600r/min, washing once with clear water after stirring, then putting into an oven with circulating air, drying for 24h at 60 ℃, properly stirring the wood flour every 3h, and drying to obtain modified wood flour;

Preparation example 4

The difference between the preparation example and the preparation example 3 is that in S2, caustic wash wood powder and 150kg of epoxy resin are placed in a high-speed mixer.

Preparation example 5

The difference between this preparation example and preparation example 3 is that in S2, caustic washed wood flour, 35kg of dibutyl phthalate and 115kg of epoxy resin were placed in a high-speed mixer.

Preparation example 6

This production example is different from production example 3 in that in S2, caustic washed wood flour, 25kg of 1-vinyl-2-pyrrolidone and 125kg of epoxy resin were put into a high-speed mixer.

Preparation example 7

This production example is different from production example 3 in that, in S2, alkaline washed wood flour, 70kg of 1-vinyl-2-pyrrolidone and 80kg of dibutyl phthalate were put into a high-speed mixer.

Preparation example 8

This production example is different from production example 3 in that the surface modification treatment of the alkali-washed wood flour was not performed.

Preparation example 9

The preparation example discloses a preparation method of a lubricant, which comprises the following specific steps: and mixing 10kg of polyethylene wax and 10kg of zinc stearate, adding into a stirrer, and stirring at the normal temperature and the rotating speed of 70r/min for 7min, wherein the mass ratio of the polyethylene wax to the zinc stearate is 1:1, thus obtaining the lubricant.

Preparation example 10

The preparation example discloses a preparation method of a lubricant, which comprises the following specific steps: 8kg of polyethylene wax, 8kg of vinyl distearamide and 4kg of polydimethylsiloxane are mixed and added into a stirrer, and the mixture is stirred for 7min at the normal temperature at the rotating speed of 70r/min, namely the mass ratio of the polyethylene wax, the vinyl distearamide and the polydimethylsiloxane is 1:1:0.5, so as to prepare the lubricant.

Preparation example 11

The preparation example discloses a preparation method of a lubricant, which comprises the following specific steps: 4.5kg of zinc stearate, 6.4kg of vinyl distearamide and 9.1kg of polydimethylsiloxane are mixed and added into a stirrer, and the mixture is stirred for 7min at the normal temperature at the rotating speed of 70r/min, namely the mass ratio of the zinc stearate to the vinyl distearamide to the polydimethylsiloxane is 0.5:0.7:1, so as to prepare the lubricant.

Preparation example 12

The preparation example discloses a preparation method of a lubricant, which comprises the following specific steps: 8kg of zinc stearate, 8kg of vinyl distearamide and 4kg of polydimethylsiloxane are mixed and added into a stirrer, and the mixture is stirred for 7min at the normal temperature at the rotating speed of 70-75r/min, namely the mass ratio of the zinc stearate to the vinyl distearamide to the polydimethylsiloxane is 1:1:0.5, so as to prepare the lubricant.

Preparation example 13

The preparation example discloses a preparation method of a lubricant, which comprises the following specific steps: 8kg of zinc stearate, 8kg of vinyl distearamide and 4kg of polydimethylsiloxane are mixed and added into a stirrer, and the mixture is stirred for 7min at the normal temperature at the rotating speed of 70-75r/min, namely the mass ratio of the zinc stearate to the vinyl distearamide to the polydimethylsiloxane is 1.2:1.5:0.7, so as to prepare the lubricant.

Examples

Example 1

The embodiment discloses an anti-aging wood-plastic composite material for wood-like furniture, which comprises the following raw materials: 100kg of polypropylene; 300kg of modified wood powder; 10kg of silane coupling agent; 5kg of foaming agent; 12kg of stabilizing agent; 5kg of lubricant; in the embodiment, the modified wood flour prepared in preparation example 1 is selected as the modified wood flour; the silane coupling agent is vinyl trimethoxy silane; the foaming agent is selected from AC foaming agent-azodicarbonamide; the stabilizer is hydrotalcite and the lubricant is polyethylene wax.

The embodiment also discloses a preparation method of the anti-aging wood-plastic composite material for the wood-like furniture, which comprises the following steps:

step one, placing polypropylene, a stabilizer, a lubricant and a foaming agent into a high-speed mixer, and stirring for 15min at the temperature of 50 ℃ and the rotating speed of 3600r/min to obtain a mixture;

adding the modified wood powder and vinyl trimethoxy silane into the mixture, and stirring for 30min at the rotating speed of 3600r/min at 70 ℃ to obtain a premix;

and step three, adding the premix into a parallel co-rotating double-screw extruder, wherein the heating temperature of each section in the double-screw extruder is 160 ℃ in the I section, 170 ℃ in the II section, 180 ℃ in the III section, 190 ℃ in the IV section, 195 ℃ in the die section of the machine head, the screw rotating speed is 7.85 multiplied by 12r/min, the traction speed is 300r/min, and the material pressure is 0.78MPa, and the premix is melted, plasticized and extruded in the extruder to form the wood aging resistant plastic composite material for the wood-like furniture.

Examples 2 to 3

The difference between the preparation method of the anti-aging wood-plastic composite material for the wood-like furniture and the embodiment 1 is that the selection, namely the addition amount of each component is different.

The amounts (unit: kg) of the respective raw material components and the process parameters of examples 1 to 3 are specified in Table 2.

TABLE 2

Examples 4 to 8

The preparation method of the anti-aging wood-plastic composite material for the wood-like furniture is different from the preparation method of the embodiment 3 in that: the lubricants prepared in preparation examples 9 to 13 are selected correspondingly in step one.

Example 9

The preparation method of the anti-aging wood-plastic composite material for the wood-like furniture is different from that of the embodiment 3 in that: adding 1kg of zinc borate and 0.5kg of nano mica powder into a stirrer, and stirring for 2min at the speed of 100r/min to obtain mixed powder for later use; adding the modified wood powder and the silane coupling agent into the mixture, stirring for 15min, adding the mixed powder, and stirring for 15 min.

Example 10

The preparation method of the anti-aging wood-plastic composite material for the wood-like furniture is different from the embodiment 8 in that: adding 3kg of zinc borate and 0.8kg of nano mica powder into a stirrer, and stirring for 2min at the speed of 100r/min to obtain mixed powder for later use; adding the modified wood powder and the silane coupling agent into the mixture, stirring for 15min, adding the mixed powder, and stirring for 15 min.

Examples 11 to 13

The preparation method of the anti-aging wood-plastic composite material for the wood-like furniture is different from the preparation method of the embodiment 3 in that: in the first step, calcium zinc stabilizers CH400, CH401 and CH402 are correspondingly selected as the stabilizers.

Example 14

A preparation method of an anti-aging wood-plastic composite material for wood-like furniture is different from embodiment 3 in that in the step one, the lubricant prepared in the preparation example 13 is selected as the lubricant; the stabilizer is calcium zinc stabilizer CH 400; adding 3kg of zinc borate and 0.8kg of nano mica powder into a stirrer, and stirring for 2min at the speed of 100r/min to obtain mixed powder for later use; adding the modified wood powder and the silane coupling agent into the mixture, stirring for 15min, adding the mixed powder, and stirring for 15 min.

Comparative example

Comparative examples 1 to 5

The difference between the preparation method of the anti-aging wood-plastic composite material for the wood-like furniture and the embodiment 3 is that the modified wood powder prepared in the preparation examples 4-8 is respectively selected as the modified wood powder.

Comparative example 6

The preparation method of the anti-aging wood-plastic composite material for the wood-like furniture is different from that in example 3 in that wood powder is not subjected to modification treatment.

Performance test

According to the detection method and standard in LY-T1613-2004 extruded wood-plastic composite board, the performance of the aging-resistant wood-plastic composite materials prepared in examples 1-14 and comparative examples 1-6 of the application is detected, and the performance detection items and indexes are detailed in Table 3:

TABLE 3

On the basis that the composite materials prepared in the examples 1 to 14 meet all the index requirements in the table 3, the application focuses on the water absorption thickness expansion rate, the static bending strength, the surface wear resistance and the high and low temperature repeated size change rate of the composite materials to be reviewed, and the specific detection data of the performance detection tests of the examples 1 to 14 and the comparative examples 1 to 6 are detailed in the tables 4 to 9.

TABLE 4

TABLE 5

According to the performance detection data of the examples 1 to 3 in the table 4, the detection results of the properties of the wood-plastic composite materials prepared in the examples 1 to 3, such as static bending strength, bending elastic modulus, impact fracture and the like, are all superior to standard indexes, and the wood-plastic composite materials prepared in the examples 1 to 3 have excellent mechanical properties, and the values of the water absorption thickness expansion rate, the state after heating, the dimensional change rate after heating and the dimensional change rate at high and low temperatures of the wood-plastic composite materials prepared in the examples 1 to 3 are small, which indicates that the aging resistance of the wood-plastic composite materials prepared in the examples 1 to 3 is good.

The inventor analyzes that wood flour is modified in the application, the modified wood flour has good dispersibility, and in the process of melting and homogenizing the modified wood flour particles and other components in the raw materials, the surface energy formed by the combined action of dibutyl phthalate, epoxy resin and 1-vinyl-2-pyrrolidone on the particle surface can be combined with a silane coupling agent and a lubricant to be crosslinked and intertwined with a polypropylene matrix, so that a bonding layer is formed on the interface of the modified wood flour and the polypropylene matrix, the bonding strength of the interface of the modified wood flour and the polypropylene matrix is greatly improved, and the wood-plastic composite material prepared in the embodiment 1-3 has good mechanical property and aging resistance.

In examples 1-3, the raw materials of the modified wood flour are selected from one or more of saw dust, corn straw powder, coconut shell powder, nut shell powder and eucalyptus wood flour, the difference of the water content values in examples 1-3 is mainly influenced by different wood flours, but the wood flours are mixed, especially in example 3, the wood flours are all mixed for modification, the performance of the prepared wood-plastic composite material is better, and the wood flours can be matched with one another through analysis of an inventor, so that the mixed wood flour has multiple performances, the modification effect is better and more obvious, and the wood flour can be matched with other components in the raw materials better.

As can be seen from comparison of the performance test data of comparative examples 1 to 6 and example 3 in Table 5, wood flour after alkali washing was subjected to surface treatment with epoxy resin in comparative example 1 and 1-vinyl-2-pyrrolidone was replaced with the same amount of epoxy resin, wood flour after alkali washing was subjected to surface treatment with epoxy resin and dibutyl phthalate in comparative example 2, wood flour after alkali washing was subjected to surface treatment with epoxy resin and 1-vinyl-2-pyrrolidone in comparative example 3, and wood flour after alkali washing was subjected to surface treatment with dibutyl phthalate and 1-vinyl-2-pyrrolidone in comparative example 4; comparative example 5 does not perform surface treatment on the wood flour after alkali washing, the performance test data of comparative examples 1-5 are obviously reduced in static bending strength and bending elastic modulus compared with the performance test data of example 3, and comparative examples 4 and 5 also have a cracking phenomenon in the impact cracking test, which indicates that the mechanical properties of the wood-plastic composite materials prepared in comparative examples 1-5 are inferior to those of the composite material prepared in example 3; secondly, in the performance tests of the water absorption thickness expansion rate, the state after heating, the dimensional change rate after heating, the high and low temperature dimensional change rate and the like, the data of the comparative examples 1-5 are obviously higher than that of the example 3, and the aging resistance of the wood-plastic composite materials prepared by the comparative examples 1-5 is not as good as that of the composite materials prepared by the example 3. And the comparative example 6 does not modify the wood powder, and the performance detection data of the wood-plastic composite material prepared in the comparative example 6 is inferior to that of the example 3 in both mechanical property detection and aging resistance detection, so that the performance of the composite material prepared in the comparative example 6 is poor.

Through comparative analysis of the data, the inventor thinks that modification of wood flour is the key for improving the mechanical property and the aging resistance of the wood-plastic composite material in the application, wherein the surface treatment of alkaline washing wood flour is more critical, and in the surface treatment, the dibutyl phthalate, the 1-vinyl-2-pyrrolidone and the epoxy resin can play a synergistic role, so that the interface bonding strength of the wood flour and the polypropylene matrix is improved, the mechanical property and the aging resistance of the composite material are further improved, and the three are mutually matched and cannot be deleted.

TABLE 6

The performance test data of example 3 and examples 4-8 in Table 6 show that the lubricants prepared in preparation examples 9-13 were selected for examples 4-8, respectively, and polyethylene wax and vinyl distearamide were selected for example 4; in the embodiment 5, polyethylene wax and vinyl distearamide polydimethylsiloxane are selected, and in the embodiment 6, a lubricant prepared by mixing zinc stearate, vinyl distearamide and polydimethylsiloxane is selected, so that the performance data of the embodiment 6 is better than those of the embodiments 4 and 5, and the performance of the composite material prepared in the embodiment 6 is improved to a certain extent; when the lubricant prepared by mixing zinc stearate, vinyl distearamide and polydimethylsiloxane is added into the formula in the mass ratio of (1-1.2) to (1-1.5) to (0.5-0.7) in the embodiments 7 and 8, the performance detection data of the wood-plastic composite material prepared in the embodiments 7 and 8 are obviously improved in static bending strength and bending elastic modulus compared with the performance detection data of the wood-plastic composite material prepared in the embodiments 3-6; the water absorption thickness expansion rate, the heated state, the heated dimensional change rate, the high and low temperature dimensional change rate and other properties are obviously reduced, which shows that the mechanical properties and the aging resistance of the wood-plastic composite materials prepared in the examples 7 and 8 are greatly improved.

Through the comparison, the inventor analyzes that the lubricant prepared by mixing zinc stearate, vinyl distearamide and polydimethylsiloxane according to the mass ratio of (1-1.2) to (1-1.5) to (0.5-0.7) is beneficial to improving the compatibility between the polypropylene matrix and the modified wood flour when being added into the formula, so that the polypropylene matrix can be fully mixed with the modified wood flour; in the process of mixing and dissolving, the three components act together to enhance the permeation and bonding effect of the components in the surface layer on the polypropylene matrix, so that the interface bonding strength of the polypropylene matrix and the modified wood powder is further enhanced, and the mechanical property and the aging resistance of the wood-plastic composite material are further improved.

TABLE 7

According to the performance detection data of the embodiment 3 and the embodiments 9 and 10 in table 7, zinc borate and nano mica powder are added in the embodiments 9 and 10, and the mixing effect of zinc borate and nano mica powder can improve the fluidity of the modified wood flour and improve the compatibility between the modified wood flour and the polypropylene matrix, so that the interface bonding strength between the modified wood flour and the polypropylene matrix is enhanced, so that the performance data of the embodiments 9 and 10 are further improved compared with the performance data of the embodiment 3, in particular, the surface wear-resistant data of the composite material prepared by the embodiments 9 and 10 is obviously reduced compared with the surface wear-resistant data of the composite material prepared by the embodiment 3, which reflects the improvement of the wear-resistant performance of the composite material prepared by the embodiments 9 and 10, and the inventor analyzes that after the zinc borate and the nano mica powder are added, the zinc borate and the nano mica powder positioned on the outer surface of the mixture can cooperate, and a covering layer is formed on the surface of the mixture at high temperature, and the covering layer enables the surface of the prepared wood-plastic composite material to be smooth and wear-resistant, so that the wear resistance of the composite material is improved.

TABLE 8

According to the performance test data of examples 3 and 11-13 in table 8, the stabilizers in examples 11-13 are respectively selected from calcium zinc stabilizers CH400, CH401 and CH402, and the calcium zinc stabilizers have excellent thermal stability and can be matched with the lubricant in the formula to endow the modified wood flour with good dispersibility and enhance the wrapping with the polypropylene matrix; compared with a common stabilizer, the calcium-zinc stabilizer can promote melting in the process of melting and homogenizing the mixture, deepens the crosslinking entanglement between the surface quality of the modified wood powder particles and the polypropylene matrix, enables the mixture to be uniformly plasticized, further improves the performance data of the composite material prepared in the embodiments 11-13 compared with the performance data of the composite material prepared in the embodiment 3, and is beneficial to improving the stability of the mechanical property and the aging resistance of the wood-plastic composite material in the application.

TABLE 9

According to the performance test data of example 3 and example 14 in table 9, in example 14, compared with example 3, the lubricant prepared in preparation example 13 is used as the lubricant, and the calcium zinc stabilizer CH400 is used as the stabilizer; in the second step, 3kg of zinc borate and 0.8kg of nano mica powder are added, so that the performance detection data of the composite material prepared in the example 14 is obviously superior to that of the composite material prepared in the example 3, and the example 14 is the best example of the application.

The above embodiments are preferred embodiments of the present application, and the protection scope of the present application is not limited by the above embodiments, so: all equivalent changes made according to the structure, shape and principle of the present application shall be covered by the protection scope of the present application.

Claims

1. An anti-aging wood-plastic composite material for wood-like furniture is characterized in that: the composite material comprises the following raw materials in parts by mass:

100 portions and 150 portions of polypropylene;

300 portions of modified wood powder and 400 portions of modified wood powder;

10-12 parts of a silane coupling agent;

5-7 parts of a foaming agent;

12-15 parts of a stabilizer;

5-8 parts of a lubricant;

s3, shaping: mixing and ball-milling the modified wood flour and triethanolamine with the mass of the wood flour being 0.3%, and screening to obtain the modified wood flour with the average grain diameter of 100 plus 120 meshes.

2. The aging-resistant wood-plastic composite material for the wood-like furniture according to claim 1, wherein: the S1 wood flour is selected from one or more of sawdust, corn straw powder, coconut shell powder, nut shell powder and eucalyptus wood flour.

3. The aging-resistant wood-plastic composite material for the wood-like furniture according to claim 1, wherein: the lubricant is prepared by mixing zinc stearate, vinyl distearamide and polydimethylsiloxane according to the mass ratio of (1-1.2) to (1-1.5) to (0.5-0.7).

4. The aging-resistant wood-plastic composite material for the wood-like furniture according to claim 3, wherein: the wood-plastic composite material also comprises the following raw materials in parts by mass: 1-3 parts of zinc borate and 0.5-0.8 part of nano mica powder.

5. The aging-resistant wood-plastic composite material for the wood-like furniture according to any one of claims 1 to 4, wherein: the stabilizer is one of calcium zinc stabilizers CH400, CH401 and CH 402.

6. A method for preparing the aging-resistant wood-plastic composite material for the wood-like furniture as claimed in any one of claims 1 to 5, wherein: the method comprises the following steps:

7. The preparation method of the aging-resistant wood-plastic composite material for the wood-like furniture as claimed in claim 6, wherein the preparation method comprises the following steps: in the second step, the modified wood powder and the silane coupling agent are added into the mixture and stirred for 10-15min, and then 1-3 parts by mass of zinc borate and 0.5-0.8 part by mass of nano mica powder are added and stirred for 10-15 min.

8. The preparation method of the aging-resistant wood-plastic composite material for the wood-like furniture as claimed in claim 7, wherein the preparation method comprises the following steps: in the second step, the zinc borate and the nano mica powder are uniformly mixed and then added into the mixture.