CN110563900A - Preparation and application of ammonia phenolic resin and heat-proof composite material - Google Patents
Preparation and application of ammonia phenolic resin and heat-proof composite material Download PDFInfo
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- CN110563900A CN110563900A CN201910791561.0A CN201910791561A CN110563900A CN 110563900 A CN110563900 A CN 110563900A CN 201910791561 A CN201910791561 A CN 201910791561A CN 110563900 A CN110563900 A CN 110563900A
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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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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K7/00—Use of ingredients characterised by shape
- C08K7/02—Fibres or whiskers
- C08K7/04—Fibres or whiskers inorganic
- C08K7/14—Glass
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08K—Use of inorganic or non-macromolecular organic substances as compounding ingredients
- C08K2201/00—Specific properties of additives
- C08K2201/002—Physical properties
- C08K2201/004—Additives being defined by their length
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2201/00—Properties
- C08L2201/08—Stabilised against heat, light or radiation or oxydation
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L2203/00—Applications
- C08L2203/18—Applications used for pipes
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- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
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- General Chemical & Material Sciences (AREA)
- Compositions Of Macromolecular Compounds (AREA)
- Reinforced Plastic Materials (AREA)
- Phenolic Resins Or Amino Resins (AREA)
Abstract
The invention discloses a preparation method of ammonia phenolic resin and a preparation and application of a heat-proof composite material, relates to the technical field of heat-proof composite materials, and provides a mould pressing resin-based composite material prepared by mixing novel ammonia phenolic resin and high silica fiber. Different moulds are opened, and various heat-insulating ablation parts, heat-insulating materials and structural materials of resin-based heat-proof composite materials such as a medicine baffle plate, a medicine fixing sleeve and the like can be processed.
Description
The technical field is as follows:
The invention relates to the technical field of heat-proof composite materials, in particular to ammonia phenolic resin and preparation and application of a heat-proof composite material.
Background art:
Phenolic resin has been developed for over 100 years, and as the synthetic resin which is the earliest industrialized, phenolic resin (PF) is widely used in industrial production, so that it is known that it is low in cost, simple in molding process, and excellent in mechanical properties and ablation resistance. The traditional thermosetting phenolic resin adopts alkaline catalyst to react with excessive formaldehyde to generate a class A resin with active groups such as hydroxymethyl, and because the synthesized raw material adopts 35-37% of liquid formaldehyde and contains a large amount of phenol-containing aldehyde-containing wastewater which is difficult to treat, according to statistics, each ton of thermosetting phenolic resin synthesized can generate about 650-900 kg of wastewater, and the development of the synthesis process is strictly limited under the increasingly strict environmental protection situation.
Phenol resin has become the most basic matrix resin for ablation resistant materials due to its high heat resistance, good adhesion and strength. At present, carbon-carbon composite materials are generally adopted as ablative materials for aerospace vehicles (such as rockets and airships) and strategic missiles at home and abroad, but the manufacturing cost is difficult to bear by conventional weapons and tactical missiles. The development of low cost, high performance resin-based ablative composites that can replace carbon-carbon composites is a major direction in the development of conventional weapons and tactical missiles. Since the first use of phenolic resins as matrix for ablative composites in the original soviet union in the united states in the 50's of the 20 th century, phenolic resins have been the predominant matrix resin for ablative composites. Although new matrix resins such as polyimide, polybenzimidazole, polyarylacetylene, etc. have been developed for over 50 years, phenolic resins are still not alternatives in low cost ablative composites and will play an important role in the development of ablative composites for the next decades.
The development of modern weapons requires not only high impact accuracy from a rocket or missile, but also high flight speed and long range impact capability. The utilization of high-energy propellant powder to increase the flying speed and flying distance of rocket projectiles or missiles inevitably causes the inner wall of the solid rocket engine to be subjected to long-time gas ablation and washing of high-density and high-speed particle flow and high pressure and high overload generated by the erosion. Therefore, the phenolic resin (PF) -based composite material for parts such as liners and nozzles of solid rocket engines is required to have not only excellent ablation resistance but also excellent mechanical properties. The non-metallic composite material has the advantages of high strength and light weight, plays an important role in the field of aerospace, and along with the development of solid rocket engine technology, people put forward higher requirements on the performance of ablative heat-proof resin-based composite materials, the high silica/phenolic aldehyde and carbon/phenolic aldehyde composite materials are widely used composite materials at present, and the high silica/phenolic aldehyde can be used for small-sized solid rocket engine mould pressing heat insulation products. In many thermal ablation resistant parts, the traditional ammonia phenolic/high silica fiber composite materials still play an important role, and the main matrix adopted by the resin-based ablation composite materials is phenolic resin and modified substances thereof.
The invention content is as follows:
The technical problem to be solved by the invention is to provide a preparation method of ammonia phenolic resin and preparation and application of a heat-proof composite material, wherein the prepared ammonia phenolic resin has good mechanical and heat-resistant properties, particularly has outstanding instantaneous high-temperature ablation resistance, and glass fiber is used as a reinforcing material widely applied in composite materials and has the characteristics of high temperature resistance, corrosion resistance, high strength, good heat insulation and good insulating property.
the technical problem to be solved by the invention is realized by adopting the following technical scheme:
A process for preparing ammonia-phenolic resin includes proportionally adding phenol, paraformaldehyde, ammonia water and assistant, controlling the temp in water bath not higher than 80 deg.C, boiling, starting condensing reflux unit, vacuum dewatering when the material becomes turbid, vacuumizing while adding industrial alcohol, stirring, and discharging at 60 deg.C.
The molar ratio of the phenol to the paraformaldehyde is 1: 1.18-1.8.
The auxiliary agent is a mixture of an alcohol solvent containing hydrogen ions and water, the mass concentration of the alcohol solvent is 1-7%, and the alcohol solvent is methanol or ethanol.
the dosage of the ammonia water is 5% of the phenol, and the dosage of the auxiliary agent is 10% of the phenol.
The purity of the industrial alcohol is 95%.
The method for preparing the heat-proof composite material by using the ammonia phenolic resin comprises the following steps:
(1) Preparation of premix: preparing an alcohol solution with the mass concentration of 50% from an ammonia phenolic resin solution, sequentially adding an internal release agent and a coupling agent, uniformly mixing, finally adding high-silica chopped fiber yarns, starting a mixer to stir, uniformly placing the mixed materials in an electric heating oven to dry, wherein the temperature of the oven is 80-100 ℃, and sealing and packaging for later use;
(2) preparing a heat-proof composite material: adjusting an oil press, cleaning a die, uniformly coating an external release agent on the surface of the die, heating the die to 90-130 ℃, filling the metered premix into the die after the temperature is constant, pressurizing at 110 ℃ under 2MPa at a heating speed of 30 ℃/h to 180 ℃, heating the pressure to 30-40MPa at 180 ℃, and curing for 3-5 min/mm.
The internal RELEASE agent is a 19W RELEASE semi-permanent RELEASE agent.
The external release agent is oleic acid.
The coupling agent is KH 550.
The length of the high silica chopped fiber filaments is 12-30 mm.
the mass ratio of the ammonia phenolic resin solution to the high-silica chopped fiber, the internal release agent to the coupling agent is 600-1000:400-800:5-10: 2-8.
The heat-proof composite material is applied to high-temperature heat-proof ablation products and small solid rocket engine nozzle heat-proof materials.
Because the solid formaldehyde depolymerization party automatically releases heat, the reaction temperature is not controlled to be too high, so that the solid formaldehyde depolymerization agent slowly depolymerizes and releases heat mildly.
The technical indexes of the ammonia phenolic resin and the common ammonia phenolic resin prepared by the invention are as follows:
The technical indexes of the premix prepared by the invention are as follows:
| Volatile fraction/%) | gel content/% | insoluble resin content/%) |
| 1-5 | 40-45 | 5-10 |
The invention provides a novel mould pressing resin matrix composite material prepared by mixing ammonia phenolic resin and high silica fiber, which has the advantages of excellent heat resistance and mechanical property, good product size stability, good machining performance, technical indexes meeting the requirements of QJ2727A-2014, GJB1595-93 and the like, and can be used as high-temperature thermal ablation resistant products and small solid rocket engine nozzle thermal protection materials. Different moulds are opened, and various heat-insulating ablation parts, heat-insulating materials and structural materials of resin-based heat-proof composite materials such as a medicine baffle plate, a medicine fixing sleeve and the like can be processed.
the invention has the beneficial effects that:
(1) The invention adopts the solid formaldehyde synthetic resin without moisture, and has no moisture brought by raw materials, thereby providing a priority condition for the green sustainable development of the resin;
(2) The prepared amino phenolic resin has good mechanical and heat resistance, especially has outstanding instantaneous high-temperature ablation resistance, and the glass fiber is used as a reinforcing material widely applied to composite materials and has the characteristics of high temperature resistance, corrosion resistance, high strength, good heat insulation and good insulating property. The phenolic resin-based heat-proof composite material is an ablation heat-proof functional composite material which is most widely applied to aerospace vehicles, and the adopted forming process mainly comprises forming process methods such as mould pressing, winding, hand pasting and the like according to different requirements of the shape and the performance of a heat-proof part.
Description of the drawings:
FIG. 1 is a TG spectrum of an ammonia phenolic resin;
FIG. 2 is a DSC chart of the amino phenol resin.
The specific implementation mode is as follows:
In order to make the technical means, the creation features, the achievement purposes and the effects of the invention easy to understand, the invention is further explained below by combining the specific drawings and the embodiments.
Example 1
In a 1000mL three-necked flask, the ratio of phenol: formaldehyde 1:1.18-1.8 mol ratio, adding 390g of phenol, 160g of paraformaldehyde, 20g of ammonia water, 2g of methanol and 38g of water, controlling the temperature of a water bath not to exceed 80 ℃, automatically releasing heat due to depolymerization of solid formaldehyde, controlling the reaction temperature not to be too high, slowly depolymerizing the solid formaldehyde, releasing heat gently, wherein the process is 2h, recording the reaction time from the material temperature of 80 ℃, controlling the reaction time to be 1.5h when the material temperature is boiled, starting a condensation reflux device when the material temperature is boiled, starting vacuum dehydration when the material is transparent and turbid after the reaction heat release peak is over, stopping vacuumizing when the specified viscosity and gel time are reached at 80S/150 ℃, adding 220g of 95% industrial alcohol into a three-neck flask while stirring, continuing to stir for 40min, and discharging at 60 ℃. The above resin solution was ready for use.
Preparing an ammonia phenolic resin solution into an alcohol solution with the concentration of 50%, sequentially adding 10g of 19W RELEAE semi-permanent mold RELEASE agent and 10g of KH550 coupling agent, uniformly mixing, finally adding high-silica chopped fiber, starting a mixer to stir, uniformly mixing for 2h, uniformly placing the mixed material in an electric heating oven to dry, wherein the temperature of the oven is 100 ℃, the time is 30min, and sealing and packaging for later use.
Adjusting a 200T four-column oil press, cleaning a die, uniformly coating oleic acid on the surface of the die, heating the die to 90-130 ℃, putting the metered mixture into the die after the temperature is constant, pressurizing at about 110 ℃, pressurizing at 2MPa at the heating speed of 30 ℃/h, finally pressurizing at 30-40MPa, and curing at 180 ℃ for 3-5 min/mm.
as can be seen from FIG. 1, the decomposition temperature of the ammonia-phenolic resin prepared by the invention is 472.2 ℃, and the carbon residue rate is 51.68% at 900 ℃.
As can be seen from FIG. 2, the curing temperature of the amino phenol-formaldehyde resin prepared by the invention is 140-175 ℃.
Example 2
the retention rates of the thermal weight loss of the prior ammonia-phenol aldehyde/high-silica composite material product and the ammonia-phenol aldehyde/high-silica composite material product prepared in the example 1 of the invention are shown in the table 1. The performance data of the composite material prepared in example 1 of the invention are shown in Table 2.
The common ammonia phenolic aldehyde/high silica composite material product is a composite material G/NPF in a paper (Shouchun, Liuyonghua, the performance research of FB resin-based composite materials, the proceedings of the ninth academic annual meeting of the glass fiber reinforced plastic society, 1991 and 10.).
Watch (A)1
Slave watch1It can be seen that the existing composite material has 11.4% weight loss at 400-500 deg.C and 17.3% weight loss at 500-600 deg.C, while the composite material made by the invention has only 3.2% weight loss at 400-500 deg.C, only 5.1% weight loss at 500-600 deg.C, and the carbon residue rate at 900 deg.C is up to 79.3%, and the composite material made by the invention has high and stable carbon residue rate, and is one of the ideal ablation material performance requirements.
Watch (A)2
| Item | QJ2727A-2014 | The invention |
| density g.cm-3 | ≥1.65 | 1.67 |
| Tensile strength MPa | ≥7.48 | 55.8 |
| bending strength MPa | / | 76.1 |
| Compressive strength MPa | ≥100 | 243 |
| Coefficient of thermal conductivity w (m.k) | ≤1.0 | 0.456 |
| Specific heat J/g/K | ≥0.8 | 1.248 |
| Line ablation rate mm/s | ≤0.15 | 0.1341 |
The composite material manufactured by the invention has the advantages that the performance completely meets the technical requirements of aerospace industry standards QJ2727A-2014, the mechanical properties such as tensile strength, bending strength and compressive strength are far higher than the aerospace industry standards, the heat conductivity coefficient is lower than the aerospace standard requirements, and the specific heat is higher than the aerospace standard requirements.
The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (10)
1. A preparation method of ammonia phenolic resin is characterized in that: adding phenol, paraformaldehyde, ammonia water and an auxiliary agent in proportion, controlling the temperature of a water bath to be not more than 80 ℃, starting a condensation reflux device when the temperature of a material is boiling, starting vacuum dehydration when the material is transparent and turbid after a reaction exothermic peak is passed, stopping vacuumizing when the specified viscosity and gel time are reached, adding industrial alcohol while stirring, continuously stirring after the addition is finished, discharging at 60 ℃, and keeping the obtained resin solution for later use.
2. The method for producing an ammonia-phenolic resin according to claim 1, characterized in that: the molar ratio of the phenol to the paraformaldehyde is 1: 1.18-1.8.
3. The method for producing an ammonia-phenolic resin according to claim 1, characterized in that: the auxiliary agent is a mixture of an alcohol solvent containing hydrogen ions and water, the mass concentration of the alcohol solvent is 1-7%, and the alcohol solvent is methanol or ethanol.
4. A method of making a heat protective composite using the ammonia phenolic resin of claim 1, comprising the steps of:
(1) preparation of premix: preparing an alcohol solution with the mass concentration of 50% from an ammonia phenolic resin solution, sequentially adding an internal release agent and a coupling agent, uniformly mixing, finally adding high-silica chopped fiber yarns, starting a mixer to stir, uniformly placing the mixed materials in an electric heating oven to dry, wherein the temperature of the oven is 80-100 ℃, and sealing and packaging for later use;
(2) Preparing a heat-proof composite material: adjusting an oil press, cleaning a die, uniformly coating an external release agent on the surface of the die, heating the die to 90-130 ℃, filling the metered premix into the die after the temperature is constant, pressurizing at 110 ℃ under 2MPa at a heating speed of 30 ℃/h to 180 ℃, heating the pressure to 30-40MPa at 180 ℃, and curing for 3-5 min/mm.
5. the method of making a heat protective composite material of claim 4, wherein: the internal RELEASE agent is a 19W RELEASE semi-permanent RELEASE agent.
6. The method of making a heat protective composite material of claim 4, wherein: the external release agent is oleic acid.
7. The method of making a heat protective composite material of claim 4, wherein: the coupling agent is KH 550.
8. The method of making a heat protective composite material of claim 4, wherein: the length of the high silica chopped fiber filaments is 12-30 mm.
9. The method of making a heat protective composite material of claim 4, wherein: the mass ratio of the ammonia phenolic resin solution to the high-silica chopped fiber, the internal release agent to the coupling agent is 600-1000:400-800:5-10: 2-8.
10. Use of the thermal protection composite material of claim 4 in high temperature thermal ablation resistant articles and thermal protection materials for jet nozzles of small solid rocket engines.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112094478A (en) * | 2020-08-21 | 2020-12-18 | 蚌埠市天宇高温树脂材料有限公司 | Fast-curing phenolic resin-based thermal protection material and preparation method thereof |
| CN117209844A (en) * | 2023-08-28 | 2023-12-12 | 蚌埠市天宇高温树脂材料有限公司 | Layered graphite carbon nitride nano-sheet containing zirconium and titanium, and preparation method and application thereof |
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| CN101440193A (en) * | 2007-11-23 | 2009-05-27 | 航天材料及工艺研究所 | Carbon / phenolic heat insulating composite material and manufacturing process thereof |
| CN106496927A (en) * | 2016-11-03 | 2017-03-15 | 华东理工大学 | A kind of low-density ablation heat insulation type composite and preparation method thereof |
| CN107189339A (en) * | 2017-06-20 | 2017-09-22 | 山东北方现代化学工业有限公司 | A kind of superfine silicon carbide high silica fiber enhancing phenolic aldehyde heat-resisting composite and preparation method thereof |
-
2019
- 2019-08-26 CN CN201910791561.0A patent/CN110563900A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101440193A (en) * | 2007-11-23 | 2009-05-27 | 航天材料及工艺研究所 | Carbon / phenolic heat insulating composite material and manufacturing process thereof |
| CN106496927A (en) * | 2016-11-03 | 2017-03-15 | 华东理工大学 | A kind of low-density ablation heat insulation type composite and preparation method thereof |
| CN107189339A (en) * | 2017-06-20 | 2017-09-22 | 山东北方现代化学工业有限公司 | A kind of superfine silicon carbide high silica fiber enhancing phenolic aldehyde heat-resisting composite and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 陈鸯飞: ""高成炭率酚醛树脂的制备及其在C/C复合材料中的应用"", 《中国博士学位论文全文数据库 工程科技I辑》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112094478A (en) * | 2020-08-21 | 2020-12-18 | 蚌埠市天宇高温树脂材料有限公司 | Fast-curing phenolic resin-based thermal protection material and preparation method thereof |
| CN117209844A (en) * | 2023-08-28 | 2023-12-12 | 蚌埠市天宇高温树脂材料有限公司 | Layered graphite carbon nitride nano-sheet containing zirconium and titanium, and preparation method and application thereof |
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Application publication date: 20191213 |