阅读说明：本技术 一种高强度环保抗菌秸秆板材的制备方法 (Preparation method of high-strength environment-friendly antibacterial straw board ) 是由 赵卫 于 2019-10-22 设计创作，主要内容包括：本发明主要涉及家具板材加工技术领域,公开了一种高强度环保抗菌秸秆板材的制备方法,包括：秸秆清洗、秸秆发酵、秸秆干燥、原料混合、一次热压、板材养生、二次热压、后处理；本发明提供的高强度环保抗菌秸秆板材的制备方法,板材以秸秆为主要原料制备而成,能够变废为宝,保护环境,原料来源广泛,价格低廉,降低了板材的生产成本,并且制备得到的板材强度高,不含甲醛,能够有效抗菌抗霉,提高了板材的加工性能和使用寿命,扩大了秸秆板材的适用范围。(The invention mainly relates to the technical field of furniture board processing, and discloses a preparation method of a high-strength environment-friendly antibacterial straw board, which comprises the following steps: straw cleaning, straw fermentation, straw drying, raw material mixing, primary hot pressing, board curing, secondary hot pressing and post-treatment; according to the preparation method of the high-strength environment-friendly antibacterial straw board, the board is prepared by taking the straw as a main raw material, waste can be turned into wealth, the environment is protected, the raw material source is wide, the price is low, the production cost of the board is reduced, the prepared board is high in strength, does not contain formaldehyde, can effectively resist bacteria and mildew, the processing performance and the service life of the board are improved, and the application range of the straw board is expanded.)

1. A preparation method of a high-strength environment-friendly antibacterial straw board is characterized by comprising the following steps:

(1) cleaning straws, namely putting the straws into clear water, ultrasonically cleaning for 20 ~ 30min, draining, and crushing to obtain cleaned straws with the length of 4 ~ 5 cm;

(2) placing the cleaned straws in a fermentation tank, adding fermentation liquor, soaking the cleaned straws in the fermentation liquor, mixing uniformly, fermenting at 20 ~ 25 deg.C for 3 ~ 4d, taking out, draining, stirring and kneading at 70 ~ 80r/min for 2 ~ 3h to obtain fermented straws;

(3) drying the fermented straws, namely putting the fermented straws into a freeze dryer, adjusting the freezing temperature to be-46 ~ -48 ℃, adjusting the shelf heating temperature to be 35 ~ 37 ℃, and freeze-drying the fermented straws until the water content is 15 ~ 17% to obtain dried straws;

(4) mixing the raw materials, namely adding the resin raw materials into a reaction kettle, gradually heating to be completely molten, uniformly mixing, adding the dried straws and the auxiliary materials, and stirring at 250 ~ 300r/min for 40 ~ 50min to obtain a mixture;

(5) primary hot pressing: paving the mixture, prepressing, and then carrying out primary hot pressing to obtain a primary hot-pressed plate;

(6) placing the primary hot-pressed board in a drying room, adjusting the temperature of the drying room to be 45 ~ 50 ℃, the environmental humidity to be 92 ~ 94%, curing for 20 ~ 25d, adjusting the temperature to be 55 ~ 60 ℃, the environmental humidity to be 84 ~ 86%, curing for 16 ~ 18d, adjusting the temperature to be natural environment, and curing for 30 ~ 35d to obtain a curing board;

(7) secondary hot pressing: carrying out secondary hot pressing, grinding and polishing on the health-preserving plate to obtain a secondary hot-pressed plate;

(8) and (3) post-treatment: and cutting the secondary hot-pressed board according to the size to obtain the high-strength environment-friendly antibacterial straw board.

2. The preparation method of the high-strength environment-friendly antibacterial straw board as claimed in claim 1, wherein the fermentation broth in the step (2) is prepared from Angel yeast 6 ~ 8, Lactobacillus bulgaricus 4 ~ 6, Lactobacillus plantarum 4 ~ 6, Bifidobacterium 3 ~ 4, Bacillus subtilis 2 ~ 3, white sugar 21 ~ 23 and water 1200 ~ 1400 in parts by weight, and is uniformly mixed and left to stand at 20 ~ 25 ℃ for 20 ~ 24h for fermentation to obtain the fermentation broth.

3. The method for preparing the high-strength environment-friendly antibacterial straw board as claimed in claim 1, wherein the resin raw material in the step (4) is added in an amount of 23 ~ 25% of the weight of the dry straw, and comprises the following raw materials, by weight, 56 ~ 58% of polylactic acid, 31 ~ 33% of phenolic resin and 15 ~ 17% of polyamide resin.

4. The preparation method of the high-strength environment-friendly antibacterial straw board as claimed in claim 1, wherein the auxiliary materials in the step (4) are added in an amount of 5 ~ 7% of the weight of the dry straw, and are composed of raw materials of, by weight, 17 ~ 19% of modified nano silicon oxide, 13 ~ 15% of nano zinc oxide, and 4 ~ 6% of aluminum borate whisker.

5. The preparation method of the high-strength environment-friendly antibacterial straw board as claimed in claim 4, wherein the modified nano silicon oxide is prepared by placing nano silicon oxide in a reaction kettle, heating to 115 ~ 120 ℃ at a speed of 2 ~ 3 ℃/min, keeping the temperature for 25 ~ 35min, naturally cooling to 40 ~ 50 ℃, adding propyl dioleate acyloxy (dioctyl phosphoryloxy) titanate, stirring at 120 ~ 140r/min for 60 ~ 70min, adding acetone 2 ~ 3 times of the weight of the nano silicon oxide, standing at room temperature for 30 ~ 40min, stirring at 150 ~ 160r/min for 20 ~ 30min, filtering, taking out precipitate, and drying to obtain the modified nano silicon oxide.

6. The preparation method of the high-strength environment-friendly antibacterial straw board as claimed in claim 5, wherein the addition amount of propyldioleacyloxy (dioctylphosphonoxy) titanate is 6 ~ 7% of the weight of nano silicon oxide.

7. The method for preparing high-strength environment-friendly antibacterial straw board as claimed in claim 1, wherein the pre-pressing in step (5) is carried out at 80 ~ 90 ℃ and 20 ~ 25 MPa.

8. The method for preparing high-strength environment-friendly antibacterial straw board as claimed in claim 1, wherein the primary hot pressing in step (5) is carried out at 140 ~ 150 ℃ and 30 ~ 35 MPa.

9. The method for preparing the high-strength environment-friendly antibacterial straw board as claimed in claim 1, wherein the secondary hot pressing in the step (5) is carried out at 120 ~ 130 ℃ and 38 ~ 42 MPa.

10. The high-strength environment-friendly antibacterial straw board prepared by the preparation method of the high-strength environment-friendly antibacterial straw board as claimed in any one of claims 1 ~ 9.

Technical Field

The invention mainly relates to the technical field of furniture board processing, in particular to a preparation method of a high-strength environment-friendly antibacterial straw board.

Background

At present, most of artificial boards in China are boards made by processing and treating waste materials such as flaw-pieces, crushed aggregates, shavings and sawdust generated in the wood processing process, but with the gradual shortage of wood resources, wood leftovers are less and less, the price is higher and higher, and the demand of board production cannot be met, so that new materials are required to be searched for preparing the boards so as to relieve the cutting and demand pressure of China on the wood.

China is a big agricultural country, straws are byproducts in agricultural production, the yield is high, the cost is low, the straws contain rich cellulose, and the straws are suitable materials for preparing the plates, so that the waste can be changed into valuable, the environment can be protected, and the production cost of the artificial plates can be reduced; but the surface layer of the straw has a waxy structure, especially wheat straw, rice straw and corn straw, the existing method for removing the waxy structure is to polish, the efficiency is low, the cost is high, the generated dust is easy to explode, the existing patent document CN107498685A discloses a method for producing a green environment-friendly rice straw board, the rice straw is not polished, chemical raw materials and adhesives which are similar or similar to the waxy structure of the rice straw are selected, the chemical raw materials comprise silicone resin, alkaline alkyl oxide, silicone alcohol ester, polyol ester, sodium salt of the silicone alcohol ester, sodium salt of the polyol ester, borax and the like, the adhesives comprise melamine formal, polyvinyl butyral, casein, oxidized starch, starch adhesive, polyvinyl alcohol, phenolic resin, epoxy resin, polyurethane and the like, a large amount of chemical raw materials and adhesives are added, and the prepared board is aged after being used for a period of time, the board is easy to separate from chemical raw materials and adhesives, so that the board prepared by the patent document has lower strength and durability; the prior patent document CN110078975A discloses a preparation process of a crop straw regenerated board, and particularly discloses a process for modifying straws for use, wherein the preparation process of the modified straws comprises the steps of crushing rice straws, corn straws, wheat straws, rape straws and the like, then adding ethanol and polyvinyl alcohol in sequence, and carrying out high-temperature and high-pressure steam explosion treatment, wherein the ethanol and the polyvinyl alcohol are chemical raw materials, and a large amount of straws still need a large amount of chemical reagents for modification, so that certain harm is generated to the environment; therefore, a high-strength environment-friendly antibacterial straw board prepared from straw is needed.

Disclosure of Invention

In order to make up for the defects of the prior art, the invention aims to provide a preparation method of a high-strength environment-friendly antibacterial straw board.

A preparation method of a high-strength environment-friendly antibacterial straw board comprises the following steps:

(1) cleaning straws, namely placing the straws in clean water for ultrasonic cleaning for 20 ~ 30min, draining, crushing the straws to the length of 4 ~ 5cm, quickly removing impurities on the surfaces of the straws, facilitating the mixing of the straws and resin raw materials, and improving the strength of the board to obtain the cleaned straws;

(2) the straw fermentation comprises the steps of putting cleaned straws in a fermentation tank, adding fermentation liquor, soaking the cleaned straws in the fermentation liquor, uniformly mixing, fermenting for 3 ~ 4d at 20 ~ 25 ℃, taking out, draining, stirring and kneading for 2 ~ 3h at 70 ~ 80r/min, adding various microorganisms into the fermentation liquor, fermenting for a long time to generate a micromolecular fermentation product to inhibit the proliferation of mould, prevent the mildew of plates, reduce the binding capacity of cellulose and lignin, soften the straw fibers, remove waxy structures on the surface layers of the straw fibers, fully compatiblizing the straw fibers and resin raw materials, improving the binding capacity of the straw fibers and the resin raw materials, enhancing the strength of the plates and obtaining the fermented straws;

(3) drying the fermented straws, namely putting the fermented straws into a freeze dryer, adjusting the freezing temperature to be-46 ~ -48 ℃, adjusting the heating temperature of a shelf to be 35 ~ 37 ℃, freeze-drying the fermented straws until the water content is 15 ~ 17%, increasing the porous structure of the straws, enabling the resin raw materials to permeate into fiber holes, increasing the bonding firmness of the straw fibers and the resin raw materials, and improving the strength of the board to obtain the dried straws;

(4) adding the resin raw materials into a reaction kettle, gradually heating to be completely molten, uniformly mixing, adding dry straws and auxiliary materials, stirring at 250 ~ 300r/min for 40 ~ 50min, fully grafting the resin raw materials, being safe and non-toxic, improving the strength and processability of the board, being beneficial to biodegradation, avoiding pollution of the waste board to the environment, being more environment-friendly, increasing the strength and flame retardant property of the board by the auxiliary materials, avoiding the inflammability of the traditional furniture board, improving the living safety, and obtaining a mixed material;

(5) primary hot pressing: paving the mixture, prepressing, and then carrying out primary hot pressing to form the plate by hot pressing, so as to improve the strength and durability of the plate and obtain a primary hot-pressed plate;

(6) placing the primary hot-pressed board in a drying room, adjusting the temperature of the drying room to 45 ~ 50 ℃, the environmental humidity to 92 ~ 94% and the curing to 20 ~ 25d, so that the pressure of the board which is just hot-pressed and formed is suddenly lost, gaps are formed in the raw materials which are not likely to be tightly combined in the high-temperature environment, adjusting the temperature to 55 ~ 60 ℃, the environmental humidity to 84 ~ 86% and the curing to 16 ~ 18d, continuously increasing the temperature, reducing the humidity, accelerating the generation of the gaps, promoting the appearance of an unstable state, adjusting the temperature to a natural environment, curing to 30 ~ 35d, improving the environmental adaptability of the straw, and obtaining the cured board;

(7) secondary hot pressing: carrying out secondary hot pressing on the health-preserving plate, reducing the hot pressing temperature, improving the hot pressing pressure, enabling the unstable state appearing in the health-preserving process to slowly tend to be stable, improving the bonding fastness and the use strength of the plate raw materials, and grinding and polishing to obtain a secondary hot-pressing plate;

(8) and (3) post-treatment: and cutting the secondary hot-pressed board according to the size to obtain the high-strength environment-friendly antibacterial straw board.

The straws in the step (1) are one or a mixture of rice straws, wheat straws and corn straws.

The fermentation liquor in the step (2) is prepared from Angel yeast 6 ~ 8, Lactobacillus bulgaricus 4 ~ 6, Lactobacillus plantarum 4 ~ 6, Bifidobacterium 3 ~ 4, Bacillus subtilis 2 ~ 3, white granulated sugar 21 ~ 23 and water 1200 ~ 1400 in parts by weight, uniformly mixing, and standing and fermenting at 20 ~ 25 ℃ for 20 ~ 24h to obtain the fermentation liquor.

The resin raw material in the step (4) is added in an amount of 23 ~ 25% of the weight of the dry straw, and comprises the following raw materials in parts by weight, namely polylactic acid 56 ~ 58, phenolic resin 31 ~ 33 and polyamide resin 15 ~ 17.

The auxiliary materials in the step (4) are added in an amount of 5 ~ 7% of the weight of the dry straws, and are composed of the following raw materials in parts by weight, namely, modified nano silicon oxide 17 ~ 19, nano zinc oxide 13 ~ 15 and aluminum borate whisker 4 ~ 6.

The modified nano silicon oxide is prepared by placing nano silicon oxide in a reaction kettle, heating to 115 ~ 120 ℃ at the speed of 2 ~ 3 ℃/min, keeping the temperature for 25 ~ 35min, naturally cooling to 40 ~ 50 ℃ at 40 3550 ℃, adding propyl dioleate acyloxy (dioctyl phosphate acyloxy) titanate, stirring at 120 ~ 140r/min for 60 ~ 70min, adding acetone with the weight of 2 ~ 3 times of that of the nano silicon oxide, standing at room temperature for 30 ~ 40min, stirring at 150 ~ 160r/min for 20 ~ 30min, filtering, taking precipitate, and drying to obtain the modified nano silicon oxide.

The addition amount of the propyldioleate acyloxy (dioctyl phosphate acyloxy) titanate is 6 ~ 7 percent of the weight of the nano silicon oxide.

And (5) pre-pressing at the temperature of 80 ~ 90 ℃ and under the pressure of 20 ~ 25 MPa.

And (5) carrying out primary hot pressing at the temperature of 140 ~ 150 ℃ and the pressure of 30 ~ 35 MPa.

And (3) carrying out secondary hot pressing in the step (5), wherein the temperature is 120 ~ 130 ℃, and the pressure is 38 ~ 42 MPa.

The high-strength environment-friendly antibacterial straw board prepared by the preparation method is high in strength and environment-friendly antibacterial straw board.

The invention has the advantages that: according to the preparation method of the high-strength environment-friendly antibacterial straw board, the board is prepared by taking straws as main raw materials, waste can be turned into wealth, the environment is protected, the raw materials are wide in source and low in price, the production cost of the board is reduced, the prepared board is high in strength and free of formaldehyde, the board can effectively resist bacteria and mildew, the processing performance and the service life of the board are improved, and the application range of the straw board is expanded; the straw board is firstly placed in clear water for ultrasonic cleaning and crushing, so that impurities on the surfaces of the straws can be quickly removed, the mixing of the straws and resin raw materials is facilitated, and the strength of the board is improved; cleaning and crushing the straw, soaking the straw in fermentation liquor for fermentation, adding various microorganisms into the fermentation liquor, and fermenting for a long time to generate a micromolecular fermentation product to inhibit the proliferation of mould, prevent the board from mildewing, reduce the binding capacity of cellulose and lignin, soften the straw fiber, remove a waxy structure on the surface layer of the straw fiber, fully compatibilize the straw fiber and a resin raw material, improve the binding capacity of the straw fiber and the resin raw material, and enhance the strength of the board; freeze-drying the straws after fermentation to increase the porous structure of the straws, so that the resin raw materials can permeate into fiber pores, the bonding fastness of the straw fibers and the resin raw materials is increased, and the strength of the plate is improved; the modified nano silicon oxide, the nano zinc oxide and the aluminum borate whisker are added into the auxiliary materials, so that the strength and the flame retardant property of the board can be improved, the inflammability of the traditional furniture board is avoided, and the living safety is improved; the mixed raw materials are paved and then are pre-pressed and hot-pressed for one time, so that the plate is hot-pressed and formed, and the strength and the durability of the plate are improved; after hot press forming, the board is placed in a drying room for curing, the environment is firstly adjusted to be a high-temperature and high-humidity environment, so that the board which is just hot press formed loses pressure suddenly, gaps which are possibly not tightly combined with the raw materials are not generated in the high-temperature environment, the temperature is continuously increased, the humidity is reduced, the generation of the gaps is accelerated, the appearance of an unstable state is promoted, and then the board is adjusted to be a natural environment, so that the environmental adaptability of the straw is improved; and after the straw board is cured, secondary hot pressing is carried out, the hot pressing temperature is reduced, the hot pressing pressure is improved, the unstable state appearing in the curing process slowly tends to be stable, the bonding fastness and the use strength of the board raw materials are improved, and the application range of the straw board is expanded.

Detailed Description

The invention is illustrated by the following specific examples.