CN110964224A - Preparation method of copolymerization type phenolic alkali lignin-based phenolic foam material - Google Patents
Preparation method of copolymerization type phenolic alkali lignin-based phenolic foam material Download PDFInfo
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- CN110964224A CN110964224A CN201911262273.2A CN201911262273A CN110964224A CN 110964224 A CN110964224 A CN 110964224A CN 201911262273 A CN201911262273 A CN 201911262273A CN 110964224 A CN110964224 A CN 110964224A
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
- C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
- C08J9/14—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent organic
- C08J9/141—Hydrocarbons
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
- C08G8/00—Condensation polymers of aldehydes or ketones with phenols only
- C08G8/28—Chemically modified polycondensates
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2203/00—Foams characterized by the expanding agent
- C08J2203/14—Saturated hydrocarbons, e.g. butane; Unspecified hydrocarbons
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2361/00—Characterised by the use of condensation polymers of aldehydes or ketones; Derivatives of such polymers
- C08J2361/04—Condensation polymers of aldehydes or ketones with phenols only
- C08J2361/06—Condensation polymers of aldehydes or ketones with phenols only of aldehydes with phenols
- C08J2361/14—Modified phenol-aldehyde condensates
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Abstract
The invention relates to a preparation method of a copolymer phenolic alkali lignin-based phenolic foam material, belonging to the field of foam materials. The method comprises the following steps: uniformly mixing alkali lignin and molten phenol according to the ratio of the alkali lignin to replace the phenol, adding distilled water and a catalyst for reaction at 140 ℃ for 2 hours, and removing the residual catalyst after the reaction to obtain a phenolated alkali lignin solution; adding a formaldehyde solution and a sodium hydroxide solution into the phenolated alkali lignin liquid, uniformly mixing, reacting at 63-67 ℃ for 1h, then reacting at 90-95 ℃ for 1h, adjusting the pH to 8.0-8.5 after the reaction to obtain phenolated alkali lignin-based phenolic resin, and evaporating water until the solid content of the phenolated alkali lignin-based phenolic resin is 55-65%; and adding a surfactant, a foaming agent and a curing agent into the phenolic alkali lignin phenolic resin, and drying to obtain the copolymer phenolic alkali lignin phenolic foam material. The method has the advantages of wide raw material source, low cost, high-value utilization of alkali lignin and environmental protection.
Description
Technical Field
The invention relates to a preparation method of a copolymer phenolic alkali lignin-based phenolic foam material, belonging to the field of foam materials.
Background
The phenolic foam is a closed-cell rigid foam plastic prepared by scientifically mixing phenolic resin, a flame retardant, a smoke suppressant, a curing agent, a foaming agent, other auxiliaries and the like, has a uniform closed-cell structure, is low in heat conductivity coefficient, good in heat insulation performance, low in water absorption and strong in vapor permeation resistance, can resist the corrosion of all inorganic acids, organic acids and organic solvents except for being possibly corroded by strong alkali, has no obvious aging phenomenon after being exposed to sunlight for a long time, has the phenomena of carbon formation, no drop, no curling and no melting under the direct action of flame, and has good flame retardant performance. The phenolic molecules only contain carbon, hydrogen and oxygen atoms, and when the phenolic molecules are subjected to pyrolysis, a small amount of CO gas is generated, no other toxic gas is generated, and the maximum smoke density is 5.0%. Meanwhile, the foam has stable size and small change rate, and the size change rate is less than 4% in the use temperature range. Phenolic foam is low cost, corresponding to only two thirds of polyurethane foam.
Phenolic foam materials have been developed greatly since the 90 s, are firstly valued by the military in English and American, are used in the fields of aerospace, national defense and military industry, are applied to places with strict fire protection requirements such as civil aircrafts, ships, stations, oil wells and the like, and are gradually pushed to the fields of high-rise buildings, hospitals, sports facilities and the like. Because polystyrene foam and polyurethane foam are flammable and do not resist high temperature, the polystyrene foam and the polyurethane foam are restricted by fire departments in some industrially developed countries, and in places with strict fire protection requirements, the government departments have plain regulations that only phenolic foam and sandwich boards thereof can be used. Therefore, the phenolic foam thermal insulation material is a high-performance material which is more suitable for being used under the environment condition with severe requirements, and has good development prospect.
Currently, phenol and formaldehyde (the main raw materials for phenolic foam production) are mainly derived from non-renewable petroleum resources. With increasing concern over the consumption of fossil fuels and their impact on the environment, there is increasing concern over the search for alternative petroleum-derived products to produce phenolic foams without sacrificing the properties of the end-use materials/products. Phenol is a major raw material of phenols, is produced from petroleum crude oil by a conventional cumene process, and has an influence on the environment. Phenol is also expensive and its price fluctuates due to fluctuations in the price of crude oil. Therefore, there is great interest in developing a more environmentally friendly, sustainable and cost effective alternative to petroleum-based phenols.
Disclosure of Invention
The invention solves the problems by using alkali lignin to replace part of phenol to obtain phenolated alkali lignin liquid through catalytic phenolation modification by solid acid, synthesizing alkali lignin-based phenolic resin, and then obtaining the copolymer phenolated alkali lignin-based phenolic foam material through foaming and curing.
The invention provides a preparation method of a copolymer type phenolic alkali lignin-based phenolic foam material, which comprises the following steps: uniformly mixing alkali lignin and molten phenol according to the ratio of the alkali lignin to replace the phenol, adding distilled water and a catalyst for reaction at 140 ℃ for 2 hours, and removing the residual catalyst after the reaction to obtain a phenolated alkali lignin solution; adding a formaldehyde solution and a sodium hydroxide solution into the phenolated alkali lignin liquid, uniformly mixing, reacting at 63-67 ℃ for 1h, then reacting at 90-95 ℃ for 1h, adjusting the pH to 8.0-8.5 after the reaction to obtain phenolated alkali lignin-based phenolic resin, and evaporating water until the solid content of the phenolated alkali lignin-based phenolic resin is 55-65%; and adding a surfactant, a foaming agent and a curing agent into the phenolic alkali lignin phenolic resin, and drying to obtain the copolymer phenolic alkali lignin phenolic foam material.
The invention preferably has the alkali lignin substituted phenol rate of 10-40%.
The invention preferably adds the distilled water in an amount of 10-12% of the mass of the phenol.
According to the invention, the catalyst is preferably HZSM-5 solid acid, and the addition amount of the catalyst is 2-6% of the total mass of the alkali lignin and the phenol.
According to the invention, the formaldehyde solution is preferably formalin, and the addition amount of the formaldehyde solution is 138-172% of the mass of phenol.
The invention is preferably that the sodium hydroxide solution is 20 percent (w/v) of sodium hydroxide solution, and the adding amount of the sodium hydroxide solution is 42 to 94 percent of the mass of the phenol.
According to the invention, preferably, the surfactant is tween-80, and the addition amount of the surfactant is 6-8% of the mass of the phenolic alkali lignin-based phenolic resin.
According to the invention, the foaming agent is preferably n-pentane, and the addition amount of the foaming agent is 10-12% of the mass of the phenolic alkali lignin-based phenolic resin.
According to the invention, the curing agent is preferably concentrated hydrochloric acid, and the addition amount of the concentrated hydrochloric acid is 12-15% of the mass of the phenolic alkali lignin-based phenolic resin.
The invention preferably adopts the following drying method: oven drying at 78-82 deg.C for 1 h.
The invention has the beneficial effects that:
the method has the advantages of wide raw material source, low cost, high-value utilization of the alkali lignin and environmental protection.
Drawings
The invention is shown in the attached figure 4,
FIG. 1 is a microstructure of a copolymer phenolic alkali lignin-based phenolic foam of varying substitution rates;
FIG. 2 is a stress-strain plot of copolyphenol alkali phenolate lignin-based phenolic foams of varying substitution rates;
FIG. 3 is a thermogravimetric plot of co-polymeric alkali-phenolated lignin-based phenolic foams of varying substitution rates;
FIG. 4 is an infrared spectrum of a copolymer phenolic alkali lignin-based phenolic foam of varying substitution.
Detailed Description
The following non-limiting examples are presented to enable those of ordinary skill in the art to more fully understand the present invention and are not intended to limit the invention in any way.
The lignin content of the alkali lignin described below was 82.25%.
Example 1
Phenolic resin with different alkali lignin substituted phenol rates
Adding alkali lignin and molten phenol (shown in table 1) corresponding to different alkali lignin substituted phenol rates into an intermittent pressure-resistant high-temperature reaction kettle equipped with a thermocouple and a mechanical stirrer, fully mixing the alkali lignin and the phenol at 50 ℃ for 10min, adding distilled water (10% of the mass of the phenol) and HZSM-5 solid acid (4% of the total mass of the alkali lignin and the phenol), stirring at 500r/min, reacting at 140 ℃ for 2h, and removing residual HZSM-5 solid acid after reaction to obtain phenolated alkali lignin liquid;
adding 37% of formaldehyde aqueous solution and 20% (w/v) of sodium hydroxide solution (the addition amount is shown in table 1) into the phenolated alkali lignin solution, mixing for 10min at 50 ℃, reacting for 1h at 65 ℃, then reacting for 1h at 92 ℃, cooling to 40 ℃ after reaction, adjusting the pH to 8.0-8.5 by using 4mol/L hydrochloric acid to obtain phenolated alkali lignin-based phenolic resin I, measuring the pH, the solid content and the viscosity of the phenolated alkali lignin-based phenolic resin I, evaporating water to obtain phenolated alkali lignin-based phenolic resin II, and measuring the solid content of the phenolated alkali lignin-based phenolic resin II, wherein the results are shown in table 2.
TABLE 1 formulation for phenolic alkali lignin based phenolic resin synthesis
TABLE 2 Properties of alkali phenolated lignin-based phenolic resins
Example 2
Influence of different substitution rates on density, slag falling rate and water absorption rate of copolymer type phenolic alkali lignin-based phenolic foam
Adding 10g of phenolic alkali lignin phenolic resin II into a paper container, adding 0.8g of tween-80 and 1.2g of n-pentane, uniformly stirring, adding 1.5g of concentrated hydrochloric acid under stirring, and then placing the paper container filled with the mixture into an oven at 80 ℃ for drying for 1h to obtain the copolymer phenolic alkali lignin phenolic foam material.
Measurement of Density: the apparent density was measured by mass of a phenolic foam of known volume (3cm x 3cm) and the results are shown in figure 1, the test data being the arithmetic mean of 3 replicates per group and the results are shown in table 3;
and (3) measuring the slag falling rate: fixing 800-mesh sand paper, placing a foam sample (the bottom area of the foam sample is 3.5cm multiplied by 3.5cm) for testing on the sand paper, placing a 100g weight on the foam sample, horizontally pulling the foam sample to and fro 20 times within a 15cm interval, weighing the mass of the foam sample before and after, and calculating the slag removal rate, wherein the result is shown in table 3;
measurement of Water absorption: take 30cm3The foam sample of (1) was weighed to have a mass of M1, immersed in distilled water at 25 ℃ for 72 hours, taken out, and the surface of the foam sample was subjected to moisture absorption by a filter paper, weighed to have a mass of M2, and the water absorption was calculated from the water absorption W ═ of (M2-M1)/V × 100%, and the results are shown in table 3;
TABLE 3 Density, slag dropping rate, water absorption rate of copolymerized phenolic alkali lignin phenolic foam with different substitution rates
Example 3
Effect of different substitution rates on the microstructure of copolyphenolized alkali phenolate lignin-based phenolic foams
Adding 10g of phenolic alkali lignin phenolic resin II into a paper container, adding 0.8g of tween-80 and 1.2g of n-pentane, uniformly stirring, adding 1.5g of concentrated hydrochloric acid under stirring, and then placing the paper container filled with the mixture into an oven at 80 ℃ for drying for 1h to obtain the copolymer phenolic alkali lignin phenolic foam material.
The cell structure of the foam samples was observed by an optical microscope and a JVC ccd image sensor having 610 ten thousand pixels, and different foam samples were observed separately at high and low magnification, and the results are shown in fig. 1.
Example 4
Effect of different substitution rates on compressive Strength of copolyphenolized alkali phenolate lignin-based phenolic foam
Adding 10g of phenolic alkali lignin phenolic resin II into a paper container, adding 0.8g of tween-80 and 1.2g of n-pentane, uniformly stirring, adding 1.5g of concentrated hydrochloric acid under stirring, and then placing the paper container filled with the mixture into an oven at 80 ℃ for drying for 1h to obtain the copolymer phenolic alkali lignin phenolic foam material.
A universal material testing machine is adopted to measure the compressive strength of the foam sample, and the specific testing steps are as follows:
a. processing foam into a foam sample with a regular shape, keeping the upper end face and the lower end face of the foam sample parallel, keeping the end faces perpendicular to the central line of the foam sample, measuring the length, the width and the height of the foam sample, calculating the area S, and making the area of the load borne by the foam sample smaller than the area of a pressing plate of a universal material testing machine so as to prepare three foam samples;
b. placing the foam sample on a universal material testing machine, aligning the center line of the foam sample with the centers of an upper pressing plate and a lower pressing plate of the universal material testing machine, applying a load to the foam sample at a constant speed of 2mm/min to deform the foam sample, and recording the maximum compressive force F when the deformation of the foam sample reaches 10% of the original deformation;
c. the compressive strength was calculated from the compressive strength σ m ═ F/S, and the results are shown in fig. 2 and table 4.
TABLE 4 compressive strength at 10% strain for foam samples
Example 5
Effect of different substitution rates on thermal stability of copolyphenol alkali lignin-based phenolic foam
Adding 10g of phenolic alkali lignin phenolic resin II into a paper container, adding 0.8g of tween-80 and 1.2g of n-pentane, uniformly stirring, adding 1.5g of concentrated hydrochloric acid under stirring, and then placing the paper container filled with the mixture into an oven at 80 ℃ for drying for 1h to obtain the copolymer phenolic alkali lignin phenolic foam material.
Thermal stability of foam samples by thermogravimetric analysis (TGA) N at 20mL/min2Heating a 5mg foam sample from room temperature to 650 ℃ at 10 ℃/minStudy, before TGA testing, foam samples were dried in an oven at 120 ℃ for 2h, ground to powder after drying, and then tested on TGA, with the results shown in figure 3.
As shown in FIG. 3, the percent weight loss of the copolymer phenolic alkali lignin-based phenolic foam at 650 ℃ gradually increased with the increase of the substitution rate, and gradually increased from 47.31% of the pure phenolic foam to 52.54% of the copolymer phenolic alkali lignin-based phenolic foam at the substitution rate of 40%.
Example 6
Influence of different substitution rates on infrared spectrum of copolymerization type phenolic alkali lignin-based phenolic foam
Adding 10g of phenolic alkali lignin phenolic resin II into a paper container, adding 0.8g of tween-80 and 1.2g of n-pentane, uniformly stirring, adding 1.5g of concentrated hydrochloric acid under stirring, and then placing the paper container filled with the mixture into an oven at 80 ℃ for drying for 1h to obtain the copolymer phenolic alkali lignin phenolic foam material.
The change of functional groups in the copolymerization type phenolic alkali lignin phenolic aldehyde foam is researched by adopting Fourier transform infrared spectroscopy, a foam sample is dried in a drying oven at 120 ℃ for 2 hours, after drying, 5-10mg of the foam sample is ground into powder, the infrared spectrum of the foam sample is measured on a Fourier transform infrared spectrometer by a KBr tabletting method, and the recording range is 4000--1The results are shown in FIG. 4.
Claims (10)
1. A preparation method of a copolymer phenolic alkali lignin-based phenolic foam material is characterized by comprising the following steps: the preparation method comprises the following steps:
uniformly mixing alkali lignin and molten phenol according to the ratio of the alkali lignin to replace the phenol, adding distilled water and a catalyst for reaction at 140 ℃ for 2 hours, and removing the residual catalyst after the reaction to obtain a phenolated alkali lignin solution;
adding a formaldehyde solution and a sodium hydroxide solution into the phenolated alkali lignin liquid, uniformly mixing, reacting at 63-67 ℃ for 1h, then reacting at 90-95 ℃ for 1h, adjusting the pH to 8.0-8.5 after the reaction to obtain phenolated alkali lignin-based phenolic resin, and evaporating water until the solid content of the phenolated alkali lignin-based phenolic resin is 55-65%;
and adding a surfactant, a foaming agent and a curing agent into the phenolic alkali lignin phenolic resin, and drying to obtain the copolymer phenolic alkali lignin phenolic foam material.
2. The method of claim 1, wherein the method comprises: the alkali lignin substituted phenol rate is 10-40%.
3. The method of claim 2, wherein the method comprises: the adding amount of the distilled water is 10-12% of the mass of the phenol.
4. The method of claim 3, wherein the method comprises: the catalyst is HZSM-5 solid acid, and the adding amount of the catalyst is 2-6% of the total mass of the alkali lignin and the phenol.
5. The method of claim 4, wherein the method comprises: the formaldehyde solution is formalin, and the addition amount of the formaldehyde solution is 138-172% of the mass of phenol.
6. The method of claim 5, wherein the method comprises: the sodium hydroxide solution is 20% (w/v) sodium hydroxide solution, and the addition amount of the sodium hydroxide solution is 42-94% of the mass of the phenol.
7. The method of claim 6, wherein the method comprises: the surfactant is tween-80, and the addition amount of the surfactant is 6-8% of the mass of the phenolic alkali lignin-based phenolic resin.
8. The method of claim 7, wherein the method comprises: the foaming agent is n-pentane, and the addition amount of the foaming agent is 10-12% of the mass of the phenolic alkali lignin-based phenolic resin.
9. The method of claim 8, wherein the method comprises: the curing agent is concentrated hydrochloric acid, and the addition amount of the concentrated hydrochloric acid is 12-15% of the mass of the phenolic alkali lignin-based phenolic resin.
10. The method of claim 9, wherein the method comprises: the drying method comprises the following steps: oven drying at 78-82 deg.C for 1 h.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4525492A (en) * | 1982-06-04 | 1985-06-25 | Fiberglas Canada Inc. | Modified phenolic foams |
| CN102504477A (en) * | 2011-10-18 | 2012-06-20 | 中国林业科学研究院林产化学工业研究所 | Lignin-modified phenolic foam and preparation method thereof |
| CN102936323A (en) * | 2012-12-03 | 2013-02-20 | 山东圣泉化工股份有限公司 | Preparation method of lignin-phenol-formaldehyde resin and preparation method of lignin-phenol-formaldehyde resin foam |
| CN104250361A (en) * | 2013-06-26 | 2014-12-31 | 中国科学院化学研究所 | Lignin modified phenolic resin, foam thereof, preparation method of resin, and preparation method of foam |
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- 2019-12-10 CN CN201911262273.2A patent/CN110964224B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4525492A (en) * | 1982-06-04 | 1985-06-25 | Fiberglas Canada Inc. | Modified phenolic foams |
| CN102504477A (en) * | 2011-10-18 | 2012-06-20 | 中国林业科学研究院林产化学工业研究所 | Lignin-modified phenolic foam and preparation method thereof |
| CN102936323A (en) * | 2012-12-03 | 2013-02-20 | 山东圣泉化工股份有限公司 | Preparation method of lignin-phenol-formaldehyde resin and preparation method of lignin-phenol-formaldehyde resin foam |
| CN104250361A (en) * | 2013-06-26 | 2014-12-31 | 中国科学院化学研究所 | Lignin modified phenolic resin, foam thereof, preparation method of resin, and preparation method of foam |
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