CN112250925A - Phosphorus-containing flame-retardant polybutadiene material and preparation method thereof - Google Patents
Phosphorus-containing flame-retardant polybutadiene material and preparation method thereof Download PDFInfo
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- CN112250925A CN112250925A CN202011112616.XA CN202011112616A CN112250925A CN 112250925 A CN112250925 A CN 112250925A CN 202011112616 A CN202011112616 A CN 202011112616A CN 112250925 A CN112250925 A CN 112250925A
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
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- C08L15/00—Compositions of rubber derivatives
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08C—TREATMENT OR CHEMICAL MODIFICATION OF RUBBERS
- C08C19/00—Chemical modification of rubber
- C08C19/24—Incorporating phosphorus atoms into the molecule
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- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F8/00—Chemical modification by after-treatment
- C08F8/40—Introducing phosphorus atoms or phosphorus-containing groups
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- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L47/00—Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds; Compositions of derivatives of such polymers
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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
- C08L2201/02—Flame or fire retardant/resistant
Abstract
The invention discloses a phosphorus-containing flame-retardant polybutadiene material and a preparation method thereof; the phosphorus-containing flame-retardant polybutadiene material consists of the following components: 60-100 parts by mass of polybutadiene grafted nitrogen-phosphorus flame retardant, 5-20 parts by mass of anti-dripping agent, 1-3 parts by mass of antioxidant and 2-5 parts by mass of other auxiliary agents; according to the invention, the flame retardant is grafted on a polybutadiene molecular chain, and flame retardant molecules are combined with polybutadiene in a covalent bond mode, so that the problems that the flame retardant is added into a polybutadiene substrate by a physical mixing method, the compatibility of the flame retardant and a polymer is poor, the flame retardant is easy to lose are solved, and the obtained polymer material has lasting flame retardance.
Description
Technical Field
The invention belongs to the field of polymer chemical synthesis, and particularly relates to a phosphorus-containing flame-retardant polybutadiene material and a preparation method thereof.
Background
Polybutadiene is mainly used as synthetic rubber, and solution polymerized polybutadiene is often used together with styrene-butadiene rubber or natural rubber as a tread and a carcass of a tire; in addition, because it is wear-resistant, it can be used as the wrapping of conveyer belt, sole, motorcycle parts, etc.; 1, 2-polybutadiene is mainly used as an adhesive and a sealant.
Polybutadiene molecular chains are composed of hydrocarbon elements, are easy to burn and have no flame retardance, and a flame retardant is usually added in the preparation of polybutadiene materials, for example, Chinese patent CN101121816B discloses a flame retardant polycarbonate/acrylonitrile-butadiene-styrene resin blend and a preparation method thereof, decabromodiphenylethane and dioxygen trioxide are added in the polycarbonate/acrylonitrile-butadiene-styrene resin; the obtained material has the comprehensive balance of high fluidity, high heat resistance and high flame resistance, and the prepared blend material has excellent flame resistance, fluidity, modulus and heat resistance and can meet the requirements of industries such as household appliances, electronics, automobile accessories and the like. The invention patent adds the flame retardant into the polycarbonate/acrylonitrile-butadiene-styrene resin substrate by a physical mixing method, and because the bonding action between the flame retardant molecules and the polycarbonate/acrylonitrile-butadiene-styrene resin substrate is weaker, the dispersion uniformity of the flame retardant is not easy to ensure, and in addition, the loss problem of the flame retardant components is difficult to avoid, thus directly influencing the long-term flame retardant property of the product; based on the above, the invention provides a phosphorus-containing flame-retardant polybutadiene material and a preparation method thereof.
Disclosure of Invention
In order to solve the defects of the prior art, the invention provides the phosphorus-containing flame-retardant polybutadiene material and the preparation method thereof, wherein the polybutadiene material has flame retardance by grafting micromolecules with flame-retardant effect on a polybutadiene molecular chain, and the flame-retardant molecules are combined with the polybutadiene in a covalent bond mode, so that the problems of poor compatibility of the flame retardant and a polymer and easy loss of the flame retardant do not exist, and the obtained polymer material has lasting flame retardance.
The invention aims to provide a phosphorus-containing flame-retardant polybutadiene material.
The invention also aims to provide a preparation method of the phosphorus-containing flame-retardant polybutadiene material.
The above purpose of the invention is realized by the following technical scheme:
the preparation method of the phosphorus-containing flame-retardant polybutadiene material comprises the following steps:
the components by weight portion are as follows: 60-100 parts by mass of polybutadiene grafted nitrogen-phosphorus flame retardant, 5-20 parts by mass of anti-dripping agent, 1-3 parts by mass of antioxidant and 2-5 parts by mass of other additives are mixed in a mixer at the temperature of 20-35 ℃ and the rotating speed of 400-800 revolutions per minute for 10-30 minutes, and the mixed material is extruded, cooled, dried and granulated at the temperature of 220-230 ℃ through an extruder to obtain the phosphorus-containing flame-retardant polybutadiene material.
The nitrogen-phosphorus flame-retardant polybutadiene grafted nitrogen-phosphorus flame retardant has a structural formula shown as the following formula (I):
the value of n is 15-50.
The reaction process and the preparation method of the nitrogen-phosphorus flame-retardant polybutadiene grafted nitrogen-phosphorus flame retardant are as follows:
the preparation method of the polybutadiene grafted nitrogen-phosphorus flame retardant comprises the following steps:
1. adding a certain amount of 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and acrylic acid into a three-neck flask, stirring, heating to 80 ℃, and carrying out reflux reaction for 6 hours to obtain a light yellow transparent mixed product; separating the product by precipitation method, dissolving with acetone, adding 1000mL chloroform as precipitant, filtering to obtain white solid product, and vacuum drying to obtain DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10V oxide
Wherein, the molar ratio of DOPO to acrylic acid is 1: 1.5.
2. Adding the DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10V oxide into a flask with a branch opening, adding tetrahydrofuran for dissolving, heating to 70-80 ℃, and dropwise adding SOCl2Carrying out acyl chlorination reaction; n is a radical of2Under protection, pyridine is used as an acid-binding agent, toluene is used as a solvent, and hydroxyl-terminated polybutadiene and the polybutadiene are subjected to esterification reaction to obtain the polybutadiene grafted nitrogen-phosphorus flame retardant.
Wherein, the DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10V oxide and SOCl2Moles of hydroxyl-terminated polybutadieneThe ratio is 1:1: 10.
The anti-dripping agent is fluorine-containing polymer.
The antioxidant is one or more selected from hindered phenols or phosphites.
The other auxiliary agents are hollow glass microspheres or solid glass microspheres.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) the invention provides a phosphorus-containing flame-retardant polybutadiene material, which leads polybutadiene molecules to have flame retardance by grafting a flame retardant on a polybutadiene molecular chain.
(2) The invention provides a phosphorus-containing flame-retardant polybutadiene material, flame-retardant molecules and covalent bonds are combined with polybutadiene, the problems that a flame retardant is added into a polybutadiene substrate by a physical mixing method, the compatibility of the flame retardant and a polymer is poor, the flame retardant is easy to lose are solved, and the obtained polymer material has lasting flame retardance.
Drawings
FIG. 1 is a nuclear magnetic hydrogen spectrum diagram of a polybutadiene grafted nitrogen phosphorus flame retardant.
Detailed Description
The present invention will be described in further detail with reference to specific examples, which are not intended to limit the present invention in any manner. Reagents, methods and apparatus used in the present invention are conventional in the art unless otherwise indicated.
Example 1
Adding 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) (4mmol) and acrylic acid (6mmol) into a three-neck flask, stirring, heating to 80 ℃, and carrying out reflux reaction for 6h to obtain a light yellow transparent mixed product; separating the product by a precipitation method, dissolving the product by acetone, adding 1000mL of chloroform as a precipitator, filtering to obtain a white solid product, and finally drying in vacuum to obtain the DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10V oxide with the yield of 80.6%.
Example 2
The DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxygenAdding hetero-10-phosphaphenanthrene-10V oxide (5.0mmol) and 20ml of anhydrous tetrahydrofuran THF into a reactor, slowly dropwise adding SOCl after the reaction temperature rises to 70 DEG C2(5.0mmol) and after the dropwise addition reaction for 2 hours, the reaction was terminated and then SOCl was removed by distillation under reduced pressure2And THF to give DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10V oxide acylchlorination product.
Hydroxyl-terminated polybutadiene (50.0mmol) was charged into a 50ml Schlenk flask, and after purging nitrogen three times, N2Under protection, 30ml of anhydrous toluene is added into a disposable injector, the temperature is raised to 70 ℃, 1ml of pyridine is injected after hydroxyl-terminated polybutadiene is completely dissolved, after stirring for 30min, the DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10V oxide acyl chloride product dissolved in the toluene is dripped, the temperature is raised to 80 ℃, the reaction is continued for 3h, the product is cooled to room temperature, and after being continuously dissolved/precipitated by toluene/methanol for twice, the product is dried to constant weight at the temperature of 45 ℃ in vacuum, the polybutadiene grafted nitrogen phosphorus flame retardant is obtained, and the yield is 70.1%.
Example 3
100 parts by mass of polybutadiene grafted nitrogen-phosphorus flame retardant, 10 parts by mass of anti-dripping agent, 2 parts by mass of composite antioxidant and 3 parts by mass of other additives are mixed in a mixer at 25 ℃ for 20 minutes at a rotating speed of 600 revolutions per minute, and the mixed material is extruded, cooled, dried and granulated by an extruder at 230 ℃ to obtain the phosphorus-containing flame-retardant polybutadiene material.
Example 4
80 parts by mass of polybutadiene grafted nitrogen-phosphorus flame retardant, 10 parts by mass of anti-dripping agent, 2 parts by mass of composite antioxidant and 3 parts by mass of other additives are mixed in a mixer at 25 ℃ for 20 minutes at a rotating speed of 600 revolutions per minute, and the mixed material is extruded, cooled, dried and granulated by an extruder at 230 ℃ to obtain the phosphorus-containing flame-retardant polybutadiene material.
Example 5
60 parts by mass of polybutadiene grafted nitrogen-phosphorus flame retardant, 10 parts by mass of anti-dripping agent, 2 parts by mass of composite antioxidant and 3 parts by mass of other additives are mixed in a mixer at 25 ℃ for 20 minutes at a rotating speed of 600 revolutions per minute, and the mixed material is extruded, cooled, dried and granulated by an extruder at 230 ℃ to obtain the phosphorus-containing flame-retardant polybutadiene material.
Comparative example 1
100 parts by mass of polybutadiene, 10 parts by mass of anti-dripping agent, 2 parts by mass of composite antioxidant and 3 parts by mass of other additives are mixed in a mixer at 25 ℃ for 20 minutes at a rotating speed of 600 revolutions per minute, and the mixed material is extruded, cooled, dried and cut into particles by an extruder at 230 ℃ to obtain the phosphorus-containing flame-retardant polybutadiene material.
Comparative example 2
80 parts by mass of polybutadiene, 10 parts by mass of anti-dripping agent, 2 parts by mass of composite antioxidant and 3 parts by mass of other additives are mixed in a mixer at 25 ℃ for 20 minutes at a rotating speed of 600 revolutions per minute, and the mixed material is extruded, cooled, dried and cut into particles by an extruder at 230 ℃ to obtain the phosphorus-containing flame-retardant polybutadiene material.
Comparative example 3
60 parts by mass of polybutadiene, 10 parts by mass of anti-dripping agent, 2 parts by mass of composite antioxidant and 3 parts by mass of other additives are mixed in a mixer at 25 ℃ for 20 minutes at a rotating speed of 600 revolutions per minute, and the mixed material is extruded, cooled, dried and cut into particles by an extruder at 230 ℃ to obtain the phosphorus-containing flame-retardant polybutadiene material.
Limiting oxygen index test: the instrument is FTAII (1600) type limit oxygen index instrument of RS company in UK, test standard GB/T2406.2-2009, spline specification 100mm x 6mm x 3mm, and a group of 5-10, before test, the spline is placed in an environment with temperature 23 + -2 deg.C and humidity 50 + -5% and adjusted for more than 88 h.
UL-94 vertical burning test: the instrument is an CZF-5A horizontal vertical combustion tester of Jiangning analytical instruments factory for carrying out UL-94 vertical combustion test, the specification of the sample bar is 125mm multiplied by 13mm multiplied by 3.2mm, and the test standard is UL94ISBN 0-7629 and 0082-2. Before testing, the sample is put in an environment with the temperature of 23 +/-2 ℃ and the humidity of 50 +/-5% and is adjusted for more than 48 h.
The flame retardant performance of the phosphorus-containing flame retardant polybutadiene material is evaluated through the limit oxygen index and the UL-94 vertical combustion test, and the results are shown in Table 1.
Table 1 shows the flame retardant properties of phosphorus-containing flame retardant polybutadiene materials.
| Sample (I) | Example 3 | Example 4 | Example 5 | Comparative example 1 | Comparative example 2 | Comparative example 3 |
| LOI(％) | 30.5 | 29.4 | 29.1 | 18.0 | 18.6 | 18.7 |
| UL-94 | V-1 | V-1 | V-1 | N.R | N.R | N.R |
As can be seen from Table 1, the flame retardant property of polybutadiene can be obviously improved by grafting the organic micromolecules with the flame retardant effect on the polybutadiene polymer chain, and the comparison of the data of the examples 3-5 and the comparative examples 1-3 shows that the LOI of pure polybutadiene is about 18.4%, when the organic micromolecules with the flame retardant effect are grafted on the polybutadiene polymer chain to modify the polyphenylenebutadiene, the LOI can reach 30.5%, and the flame retardant property of the polyphenylenebutadiene is effectively improved.
The above embodiments are preferred embodiments of the present invention, but the present invention is not limited to the above embodiments, and any other changes, modifications, substitutions, combinations, and simplifications which do not depart from the spirit and principle of the present invention should be construed as equivalents thereof, and all such changes, modifications, substitutions, combinations, and simplifications are intended to be included in the scope of the present invention.
Claims (8)
1. The phosphorus-containing flame-retardant polybutadiene material is characterized by comprising the following components in parts by weight: 60-100 parts by mass of a polybutadiene grafted nitrogen-phosphorus flame retardant, 5-20 parts by mass of an anti-dripping agent, 1-3 parts by mass of an antioxidant and 2-5 parts by mass of other auxiliaries, wherein the polybutadiene grafted nitrogen-phosphorus flame retardant has a structure shown in a formula (I):
the value of n is 15-50.
2. The method for preparing phosphorus-containing flame-retardant polybutadiene material according to claim 1, wherein it comprises the following steps:
60-100 parts by mass of polybutadiene grafted nitrogen-phosphorus flame retardant, 5-20 parts by mass of anti-dripping agent, 1-3 parts by mass of antioxidant and 2-5 parts by mass of other additives are mixed in a mixer at the temperature of 20-35 ℃ and the rotating speed of 400-800 revolutions per minute for 10-30 minutes, and the mixed material is extruded, cooled, dried and granulated at the temperature of 220-230 ℃ through an extruder to obtain the phosphorus-containing flame-retardant polybutadiene material.
3. The phosphorus-containing flame-retardant polybutadiene material according to claim 1, wherein the preparation method of the polybutadiene grafted nitrogen-phosphorus flame retardant comprises the following steps:
(1) adding a certain amount of 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and acrylic acid into a three-neck flask, stirring, heating to 80 ℃, and carrying out reflux reaction for 6 hours to obtain a light yellow transparent mixed product; separating the product by a precipitation method, dissolving the product by acetone, adding 1000mL of chloroform as a precipitator, filtering to obtain a white solid product, and finally performing vacuum drying to obtain the DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10V oxide;
(2) adding the DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10V oxide into a flask with a branch opening, adding tetrahydrofuran for dissolving, heating to 70-80 ℃, and dropwise adding SOCl2Carrying out acyl chlorination reaction; n is a radical of2Under protection, pyridine is used as an acid-binding agent, toluene is used as a solvent, and hydroxyl-terminated polybutadiene and the polybutadiene are subjected to esterification reaction to obtain the polybutadiene grafted nitrogen-phosphorus flame retardant.
4. The phosphorus-containing flame-retardant polybutadiene material according to claim 3, wherein in the preparation method of the polybutadiene grafted nitrogen-phosphorus flame retardant in step (1), the molar ratio of DOPO to acrylic acid is 1: 1.5.
5. The phosphorus-containing flame-retardant polybutadiene material of claim 3, wherein in the preparation method of polybutadiene grafted with N-P flame retardant, in step (2), the DOPO derivative 10-propionic acid-9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10V oxide, SOCl2The molar ratio to hydroxyl-terminated polybutadiene is 1:1: 10.
6. The phosphorus-containing flame retardant polybutadiene material of claim 1, wherein the anti-dripping agent is a fluoropolymer.
7. The phosphorus-containing flame-retardant polybutadiene material according to claim 1, wherein said antioxidant is one or more selected from hindered phenols and phosphites.
8. The phosphorus-containing flame-retardant polybutadiene material as claimed in claim 1, wherein said other additives are hollow glass microspheres or solid glass microspheres.
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| CN202011112616.XA CN112250925A (en) | 2020-10-16 | 2020-10-16 | Phosphorus-containing flame-retardant polybutadiene material and preparation method thereof |
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| CN202011112616.XA CN112250925A (en) | 2020-10-16 | 2020-10-16 | Phosphorus-containing flame-retardant polybutadiene material and preparation method thereof |
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