CN115716882A - Modified cellulose nanocrystal and preparation method and application thereof - Google Patents
Modified cellulose nanocrystal and preparation method and application thereof Download PDFInfo
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Abstract
The invention relates to a modified cellulose nanocrystal and a preparation method and application thereof. The preparation method of the modified cellulose nanocrystal comprises the following steps: (1) Dispersing microcrystalline cellulose in sodium periodate aqueous solution, then reacting at 60-80 ℃ for 70-90min, cooling to room temperature after the reaction is finished, washing, and drying to obtain cellulose nanocrystal; (2) Dispersing cellulose nanocrystals in water, adding a melamine aqueous solution, reacting at 60-80 ℃ for 10-30min, adding a phytic acid aqueous solution, reacting at 60-80 ℃ for 10-30min, cooling to room temperature after the reaction is finished, washing, and drying to obtain the modified cellulose nanocrystals. The modified cellulose nanocrystal prepared by the invention is a novel flame retardant integrating a carbon source, a gas source and an acid source, has high thermal stability and excellent flame retardant property, and is simple in preparation process, environment-friendly and low in cost.
Description
Technical Field
The invention belongs to the technical field of material modification, and particularly relates to a modified cellulose nanocrystal and a preparation method and application thereof.
Background
Synthetic polymers are the primary raw materials for manufacturing industrial and consumer products. The flammability of petroleum derived polymers has been recognized as an important safety issue. The most widely used thermoplastic polymers, such as Polyethylene (PE), polypropylene (PP), polystyrene (PS), poly (methyl methacrylate) (PMMA) and Acrylonitrile Butadiene Styrene (ABS), have poor fire performance in the absence of flame retardants. Their limiting oxygen index is less than 19% (average atmospheric oxygen content is 21%). Polyolefins can degrade and decompose upon exposure to high temperatures and produce toxic gases. Flame retardants are typically added to polymeric materials as additives or active materials. Inorganic reactive fillers and halides are widely used for flame resistance of fiber reinforced polymer composites. Widely used metal hydroxides require loading levels of 60% or more, which will have a detrimental effect on viscosity and mechanical properties. The inorganic filler has the defects of poor compatibility, easy leaching, low mechanical property and the like. Halogenated flame retardants, when burned, release toxic gases that cause 80% of fire deaths. In addition, a wide variety of other toxic substances, most notably HBr and bromophenol/benzene are produced. With the increasing concern of people on sustainable ecological systems and environmental protection, renewable energy and abundant natural resources are gradually developed as raw materials of the flame retardant, so that the damage to the environment can be reduced, and non-renewable resources can be saved. These factors indicate that there is a strong need for a safer, effective and environmentally friendly fire retardant system.
Intumescent Flame Retardants (IFRs) are composed of a carbon source, an acid source and a gas source, and have the advantages of low smoke, low toxicity, environmental friendliness, high efficiency and the like, so that the IFRs become one of the research hotspots in the fields at home and abroad at present. Cellulose is one of the most abundant biodegradable polymers in the world, and has the unique characteristics of no toxicity, low price, renewable resources, temperature resistance, pH value change resistance and the like. Cellulose has a molecular structure rich in polyhydroxy, and can form a cross-linked carbon layer in the combustion process. However, the flammability of cellulose limits its further use as a flame retardant.
Disclosure of Invention
Based on the above disadvantages and shortcomings of the prior art, it is an object of the present invention to at least solve one or more of the above problems in the prior art, in other words, to provide a modified cellulose nanocrystal, a preparation method and applications thereof, which satisfy one or more of the above requirements.
In order to achieve the purpose, the invention adopts the following technical scheme:
a preparation method of modified cellulose nanocrystals comprises the following steps:
(1) Dispersing microcrystalline cellulose in sodium periodate aqueous solution, then reacting at 60-80 ℃ for 70-90min, cooling to room temperature after the reaction is finished, washing, and drying to obtain cellulose nanocrystal;
(2) Dispersing cellulose nanocrystals in water, then adding a melamine aqueous solution, reacting at 60-80 ℃ for 10-30min, then adding a phytic acid aqueous solution, reacting at 60-80 ℃ for 10-30min, after the reaction is finished, cooling to room temperature, washing, and drying to obtain the modified cellulose nanocrystals.
Preferably, in the step (1), the solid-liquid mass ratio of the microcrystalline cellulose to the aqueous sodium periodate solution is 1: (90-110).
Preferably, the concentration of the sodium periodate aqueous solution is 0.5 to 1M.
Preferably, in the step (2), the solid-liquid mass ratio of melamine to water in the melamine aqueous solution is (1-2): 20.
preferably, in the step (2), the mass fraction of the phytic acid in the phytic acid aqueous solution is 60-70%.
Preferably, in the step (2), the ratio of the cellulose nanocrystals to the aqueous solution of melamine and the aqueous solution of phytic acid in parts by mass is 1: (1-3): (1-3).
Preferably, the cellulose nanocrystal is a nanosphere structure.
The invention also provides the modified cellulose nanocrystal prepared by the preparation method in any one of the above schemes.
As a preferred scheme, the modified cellulose nanocrystal is a petal-shaped nano lamellar structure.
The invention also provides application of the modified cellulose nanocrystal as described in any one of the above aspects as a flame retardant.
Compared with the prior art, the invention has the beneficial effects that:
the invention utilizes melamine as gas source, and generates a large amount of nonflammable nitrogen-containing gas NH in the combustion process 3 、N 2 And NO 2 Diluting the combustible volatile matter equally; phytic acid is used as an acid source, and phosphoric acid substances generated by heating and dehydration of the phytic acid promote high polymers to be dehydrated into carbon; the cellulose nanocrystals are used as carbon sources, and under the synergistic effect of the carbon sources, melamine and phytic acid, a compact carbon layer is formed, so that the carbon layer can not only prevent external heat and oxygen from entering the material to play a barrier role, but also effectively inhibit the release of heat and smoke.
The modified cellulose nanocrystal prepared by the invention is a novel flame retardant integrating a carbon source, a gas source and an acid source, has high thermal stability, excellent flame retardant property, simple preparation process, environmental protection and low cost, and has wide application prospects in the fields of nano composite and reinforced materials, biomedicine, textile and the like.
Drawings
FIG. 1 is a scanning electron micrograph of a cellulose nanocrystal of example 1 of the present invention;
FIG. 2 is a scanning electron micrograph of modified cellulose nanocrystals according to example 1 of the present invention;
FIG. 3 is an infrared spectrum of the cellulose nanocrystal and the modified cellulose nanocrystal of example 1 of the present invention;
fig. 4 is a thermogravimetric plot of modified cellulose nanocrystals of example 1 of the present invention, modified cellulose nanocrystals of comparative examples 1-4, and cellulose nanocrystal CNC.
Detailed Description
The technical solution of the present invention is further explained by the following specific examples.
Example 1:
the preparation method of the modified cellulose nanocrystal comprises the following steps:
(1) Dispersing 2 parts of microcrystalline cellulose in 100 parts of 0.5M sodium periodate aqueous solution, then reacting for 90min at 60 ℃, cooling to room temperature after the reaction is finished, washing and drying to obtain aldehyde group-containing cellulose nanocrystal;
(2) Dispersing 1 part of cellulose nanocrystals in deionized water, then adding 1 part of melamine aqueous solution (the solid-liquid mass ratio of melamine to water is 1: 20), reacting at 80 ℃ for 10min, then adding 2 parts of phytic acid aqueous solution (the mass fraction of phytic acid is 70%), reacting at 80 ℃ for 30min, cooling to room temperature after the reaction is finished, centrifugally separating, washing and drying to obtain the modified cellulose nanocrystals CNC @ MEL @ PA.
As shown in figure 1, the aldehyde group-containing cellulose nanocrystal is of a nano spherical structure, and a nano layer is generated under the action of p-p accumulation and hydrogen bond, so that the modified cellulose nanocrystal CNC @ MEL @ PA is of a petal-shaped nano layered structure.
As shown in FIG. 2, the cellulose nanocrystal is 1500-2000cm -1 The occurrence of a carbon-oxygen double bond (C = O); subsequently reacting with amino of melamine with Schiff base at 1500cm -1 The new peak appears at the left and the right is the vibration of the grafted triazine ring structure of 1080cm -1 And 1190cm -1 The left and the right represent P-O and P = O respectively, which indicates the success of the grafting modification.
Example 2:
the preparation method of the modified cellulose nanocrystal comprises the following steps:
(1) Dispersing 2 parts of microcrystalline cellulose in 100 parts of 0.5M sodium periodate aqueous solution, then reacting for 90min at 60 ℃, cooling to room temperature after the reaction is finished, washing and drying to obtain aldehyde group-containing cellulose nanocrystal;
(2) Dispersing 1 part of cellulose nanocrystal in deionized water, then adding 1 part of melamine aqueous solution (the solid-liquid mass ratio of melamine to water is 1.
Example 3:
the preparation method of the modified cellulose nanocrystal comprises the following steps:
(1) Dispersing 2 parts of microcrystalline cellulose in 100 parts of 0.5M sodium periodate aqueous solution, then reacting for 90min at 60 ℃, cooling to room temperature after the reaction is finished, washing and drying to obtain aldehyde group-containing cellulose nanocrystal;
(2) Dispersing 1 part of cellulose nanocrystal in deionized water, then adding 1 part of melamine aqueous solution (the solid-liquid mass ratio of melamine to water is 1: 20), reacting at 80 ℃ for 10min, then adding 3 parts of phytic acid aqueous solution (the mass fraction of phytic acid is 70%), reacting at 80 ℃ for 30min, after the reaction is finished, cooling to room temperature, centrifugally separating, washing and drying to obtain the modified cellulose nanocrystal CNC @ MEL @ PA.
Comparative example 1:
the preparation method of the modified cellulose nanocrystal of the present comparative example is different from that of example 1 in that: the phytic acid modification was not performed.
Specifically, the preparation method of the modified cellulose nanocrystal of the present comparative example includes the steps of:
(1) Dispersing 2 parts of microcrystalline cellulose in 100 parts of 0.5M sodium periodate aqueous solution, then reacting for 90min at 60 ℃, cooling to room temperature after the reaction is finished, washing and drying to obtain aldehyde group-containing cellulose nanocrystal;
(2) Dispersing 1 part of cellulose nanocrystals in deionized water, then adding 1 part of melamine aqueous solution (the solid-liquid mass ratio of melamine to water is 1.
Comparative example 2:
the preparation method of the modified microcrystalline cellulose of the present comparative example comprises the steps of:
dispersing 1 part of microcrystalline cellulose (MCC) in deionized water, then adding 1 part of melamine aqueous solution (the solid-liquid mass ratio of melamine to water is 1: 20), reacting at 80 ℃ for 10min, then adding 2 parts of phytic acid aqueous solution (the mass fraction of phytic acid is 70%), reacting at 80 ℃ for 30min, cooling to room temperature after the reaction is finished, performing centrifugal separation, washing and drying to obtain modified microcrystalline cellulose MCC @ MEL @ PA.
Comparative example 3:
the preparation method of the flame retardant of the comparative example comprises the following steps:
(1) Dissolving chitosan powder in acetic acid water solution to prepare CS solution; diluting 1 part of nano-cellulose dispersion with water to obtain a CNF dispersion; then, uniformly mixing and stirring the CS solution and the CNF dispersion liquid according to the mass ratio (1;
(2) Dissolving 1 part of Melamine (MEL) in deionized water at 80 ℃ (the solid-liquid mass ratio of the melamine to the water is 1; then adding CNF aerogel into MEL solution, gradually adding Phytic Acid (PA) (1/6 mol of MEL) into the solution within 25min, reacting at 80 ℃ for 30min, cooling to room temperature after the reaction is finished, centrifuging, washing, and drying to obtain CNF @ MEL @ PA.
Comparative example 4:
the preparation method of the modified microcrystalline cellulose of this comparative example differs from that of example 1 in that: the addition sequence of the melamine and the phytic acid is opposite, namely, the phytic acid is added for reaction firstly, and then the melamine is added for reaction;
the other steps are the same as in example 1.
The thermal stability of the product was evaluated using a thermogravimetric analyzer (TG 209F 1, netzsch), and the thermogravimetric results of the Cellulose Nanocrystals (CNC), example 1 and comparative examples 1 to 4 are shown in fig. 4. Comparative example 1 comparison with CNC, T max Increasing from 208.8 ℃ to 225.8 ℃ increased the char residue at 600 ℃ from 29.4% to 34.9%, indicating that melamine acts as a source of intumescent flame retardant and that the evolution of the generated inert gas (ammonia) can promote the formation of an intumescent char layer. Example 1 comparison with CNC, T max Increase to 440 ℃ from 208.8 ℃, promote to 44.9% from 29.4% at 600 ℃ carbon residue, CNC @ MEL @ PA's maximum mass loss rate reduces, this is because the charcoal layer has slowed down mass transfer speed, has improved CNC @ MEL @ PA's heat resistance greatly, has prevented the further degradation of base member. Example 1 compared with comparative example 4, although the materials are the same except that the order of adding melamine and phytic acid is different, the thermal stability and limiting oxygen index of example 1The comparison ratio is higher than 4, because melamine is added firstly, the amino group of the melamine can generate Schiff base reaction with the aldehyde group of the cellulose nanocrystal, phytic acid is added after the full reaction is finished, and the phosphoric acid group of the phytic acid can further interact with the amino group of the melamine; if the phytic acid is added firstly and the melamine is added, the aldehyde group of the melamine, the phytic acid and the cellulose nanocrystal reacts simultaneously, so that the loading capacity of MEL @ PA on the CNC is reduced; while an increase in the loading of MEL @ PA favours the formation of carbon residues, the results show that: the modified cellulose nanocrystal of example 1 has more excellent thermal stability.
The flame retardant performance of each of the above samples was evaluated as shown in table 1.
TABLE 1 LOI index of each sample
| Sample (I) | LOI index (%) |
| CNC | 28.9 |
| Example 1 | 36.6 |
| Comparative example 1 | 31.2 |
| Comparative example 2 | 30.6 |
| Comparative example 3 | 32.3 |
| Comparative example 4 | 33.9 |
As can be seen from table 1, the modified cellulose nanocrystal of example 1 has excellent flame retardant properties, and can be used as a flame retardant in the fields of nanocomposites, reinforcements, biomedicine, textiles, and the like.
In the above embodiment and its alternative, in the preparation process of the cellulose nanocrystal, the solid-liquid mass ratio of the microcrystalline cellulose to the sodium periodate aqueous solution may also be 1: 90. 1: 95. 1: 105. 1:110, etc., the concentration of the sodium periodate aqueous solution can be 0.6M, 0.7M, 0.8M, 0.9M, 1.0M, etc., the reaction temperature can be 65 ℃, 70 ℃, 75 ℃, 80 ℃, etc., and the reaction time can be 70min, 75min, 80min, 85min, etc.
In the above embodiments and alternatives thereof, the solid-liquid mass ratio of melamine to water in the aqueous melamine solution may also be 1.2: 20. 1.5: 20. 1.7: 20. 2:20, etc.
In the above embodiments and the alternatives, after the melamine aqueous solution is added, the reaction temperature may be 60 ℃, 65 ℃, 70 ℃, 75 ℃ and the like, and the reaction time may be 12min, 15min, 20min, 25min, 30min and the like.
In the above embodiments and alternatives thereof, the mass fraction of the phytic acid in the phytic acid aqueous solution can also be 60%, 62%, 65%, 68%, 70%, etc.
In the above embodiment and its alternative, the reaction temperature may be 60 ℃, 65 ℃, 70 ℃, 75 ℃ and the like after adding the phytic acid aqueous solution, and the reaction time may be 10min, 12min, 15min, 20min, 25min, 28min and the like.
In the above embodiment and its alternatives, the ratio of the cellulose nanocrystals to the aqueous solution of melamine and the aqueous solution of phytic acid in parts by mass may also be 1:3: 1. 1:2: 2. 1:2: 3. 1:3:3, etc.
In view of the numerous embodiments of the present invention, the experimental data of each embodiment is huge and is not suitable for being listed and explained herein one by one, but the contents to be verified and the final conclusions obtained by each embodiment are close.
The foregoing has outlined, rather broadly, the preferred embodiment and principles of the present invention in order that those skilled in the art may better understand the detailed description of the invention without departing from its broader aspects.
Claims (10)
1. A preparation method of modified cellulose nanocrystals is characterized by comprising the following steps:
(1) Dispersing microcrystalline cellulose in sodium periodate aqueous solution, then reacting at 60-80 ℃ for 70-90min, cooling to room temperature after the reaction is finished, washing, and drying to obtain cellulose nanocrystal;
(2) Dispersing cellulose nanocrystals in water, adding a melamine aqueous solution, reacting at 60-80 ℃ for 10-30min, adding a phytic acid aqueous solution, reacting at 60-80 ℃ for 10-30min, cooling to room temperature after the reaction is finished, washing, and drying to obtain the modified cellulose nanocrystals.
2. The preparation method according to claim 1, wherein in the step (1), the solid-liquid mass ratio of the microcrystalline cellulose to the aqueous sodium periodate solution is 1: (90-110).
3. The method according to claim 2, wherein the concentration of the aqueous solution of sodium periodate is 0.5 to 1M.
4. The production method according to claim 1, characterized in that in the step (2), the solid-liquid mass ratio of melamine to water in the melamine aqueous solution is (1-2): 20.
5. the method according to claim 1, wherein in the step (2), the phytic acid in the phytic acid aqueous solution is 60 to 70% by mass.
6. The preparation method according to claim 1, wherein in the step (2), the ratio of the cellulose nanocrystals to the aqueous solution of melamine and the aqueous solution of phytic acid in parts by mass is 1: (1-3): (1-3).
7. The production method according to claim 1, wherein the cellulose nanocrystal is a nanosphere structure.
8. The modified cellulose nanocrystal produced by the production method according to any one of claims 1 to 7.
9. The modified cellulose nanocrystal of claim 8, wherein the modified cellulose nanocrystal is a petal-like nanolaminate structure.
10. Use of the modified cellulose nanocrystals according to claim 8 or 9 as flame retardants.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116288812A (en) * | 2023-05-12 | 2023-06-23 | 广东奥林科技实业有限公司 | Preparation method and application of bio-based spandex fiber fabric |
| CN117903490A (en) * | 2024-03-19 | 2024-04-19 | 北京大学 | Hollow sphere reinforced cellulose aerogel heat insulation material and preparation method thereof |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102877287A (en) * | 2012-10-19 | 2013-01-16 | 常州大学 | Preparation method of halamine-containing antibacterial cellulose fabric |
| CN104804218A (en) * | 2015-04-28 | 2015-07-29 | 中科院广州化学有限公司南雄材料生产基地 | Nanocellulose surface-modified core-shell structure fire retardant, and preparation method and application of fire retardant |
| CN111205483A (en) * | 2020-02-28 | 2020-05-29 | 苏州科技大学 | Cellulose nanocrystalline water/aerogel and preparation method thereof |
| CN112961253A (en) * | 2021-02-20 | 2021-06-15 | 南通纺织丝绸产业技术研究院 | Method for flame-retardant modification of microcrystalline cellulose by phytic acid |
| CN114874357A (en) * | 2022-06-28 | 2022-08-09 | 河北科技大学 | Hemicellulose-based intumescent flame retardant and preparation method thereof |
-
2022
- 2022-11-30 CN CN202211527618.4A patent/CN115716882B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102877287A (en) * | 2012-10-19 | 2013-01-16 | 常州大学 | Preparation method of halamine-containing antibacterial cellulose fabric |
| CN104804218A (en) * | 2015-04-28 | 2015-07-29 | 中科院广州化学有限公司南雄材料生产基地 | Nanocellulose surface-modified core-shell structure fire retardant, and preparation method and application of fire retardant |
| CN111205483A (en) * | 2020-02-28 | 2020-05-29 | 苏州科技大学 | Cellulose nanocrystalline water/aerogel and preparation method thereof |
| CN112961253A (en) * | 2021-02-20 | 2021-06-15 | 南通纺织丝绸产业技术研究院 | Method for flame-retardant modification of microcrystalline cellulose by phytic acid |
| CN114874357A (en) * | 2022-06-28 | 2022-08-09 | 河北科技大学 | Hemicellulose-based intumescent flame retardant and preparation method thereof |
Non-Patent Citations (5)
| Title |
|---|
| XIAOLEI LUO等: ""A facile strategy to achieve efficient flame-retardant cotton fabric with durable and restorable fire resistance"", 《CHEMICAL ENGINEERING JOURNAL》, vol. 430, pages 1 - 13 * |
| XIKAI LI等: ""Supramolecular hydrogen-bonded organic networks grown on cellulose fibers for efficient proton conduction"", 《CELLULOSE》, vol. 29, pages 6247, XP037880783, DOI: 10.1007/s10570-022-04658-8 * |
| XUEYONG REN等: ""Fire-Retardant and Thermal-Insulating Cellulose Nanofibril Aerogel Modified by In Situ Supramolecular Assembly of Melamine and Phytic Acid"", 《ADV. ENG. MATER.》, vol. 24, pages 1 - 10 * |
| ZAIHANG ZHENG等: ""Fabrication of cellulose-based halogen-free flame retardant and its synergistic effect with expandable graphite in polypropylene"", 《CARBOHYDRATE POLYMERS》, vol. 213, pages 257 - 265, XP085632075, DOI: 10.1016/j.carbpol.2019.02.088 * |
| 周青青等: ""阻燃抗菌棉织物的制备及其性能表征"", 《纺织学报》, vol. 41, no. 5, pages 112 - 120 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116288812A (en) * | 2023-05-12 | 2023-06-23 | 广东奥林科技实业有限公司 | Preparation method and application of bio-based spandex fiber fabric |
| CN116288812B (en) * | 2023-05-12 | 2023-07-18 | 广东奥林科技实业有限公司 | Preparation method and application of bio-based spandex fiber fabric |
| CN117903490A (en) * | 2024-03-19 | 2024-04-19 | 北京大学 | Hollow sphere reinforced cellulose aerogel heat insulation material and preparation method thereof |
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