CN112250959A - Nitrogen-phosphorus flame-retardant polystyrene and preparation method thereof - Google Patents
Nitrogen-phosphorus flame-retardant polystyrene and preparation method thereof Download PDFInfo
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- CN112250959A CN112250959A CN202011111335.2A CN202011111335A CN112250959A CN 112250959 A CN112250959 A CN 112250959A CN 202011111335 A CN202011111335 A CN 202011111335A CN 112250959 A CN112250959 A CN 112250959A
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- C08L—COMPOSITIONS OF MACROMOLECULAR COMPOUNDS
- C08L25/00—Compositions of, homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, each having only one carbon-to-carbon double bond, and at least one being terminated by an aromatic carbocyclic ring; Compositions of derivatives of such polymers
- C08L25/02—Homopolymers or copolymers of hydrocarbons
- C08L25/04—Homopolymers or copolymers of styrene
- C08L25/06—Polystyrene
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- C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
- C08F8/00—Chemical modification by after-treatment
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- 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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- C—CHEMISTRY; METALLURGY
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- C08L2201/02—Flame or fire retardant/resistant
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- C—CHEMISTRY; METALLURGY
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- C08L2205/06—Polymer mixtures characterised by other features having improved processability or containing aids for moulding methods
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Abstract
The invention discloses a nitrogen-phosphorus flame-retardant polystyrene and a preparation method thereof; the nitrogen-phosphorus flame-retardant polystyrene comprises the following components in parts by weight: 100 parts by mass of polystyrene grafted nitrogen-phosphorus flame retardant, 5-20 parts by mass of toughening agent, 0.5-1.5 parts by mass of antioxidant and 0.5-1 part by mass of lubricant; the nitrogen-phosphorus flame-retardant polystyrene prepared by grafting the flame retardant on the polystyrene molecular chain enables the polystyrene molecular chain to have flame retardance, solves the problems that the dispersion uniformity of the flame retardant is not easy to ensure, the loss of flame-retardant components is difficult to avoid and the long-term flame retardance of products is directly influenced, and enables the polystyrene to have stable and lasting flame retardance by connecting the polystyrene and the flame retardant together through a covalent bond.
Description
Technical Field
The invention belongs to the field of polymer chemical synthesis, and particularly relates to nitrogen-phosphorus flame-retardant polystyrene and a preparation method thereof.
Background
Polystyrene is an organic hydrocarbon, has a limiting oxygen index of only 18.0 percent, and belongs to the field of combustible materials. Once ignited, at a temperature of 1.3-6.4 cm.min-1The combustion of the PS product generates a large amount of smoke, toxic gases and molten droplets, which is determined by the molecular structure of PS itself: the larger benzene ring on the side chain is very easy to be heatedThe incomplete combustion is removed, which results in the formation of dense smoke and molten droplets; compared with open fire, dense smoke and toxic gas are easier to suffocate and die, the foaming type styrene material is more serious in case of fire, and the regular honeycomb-shaped and closed cell structure increases the air circulation and enables the combustion of the material to be easier.
Polystyrene molecular chains are composed of hydrocarbon elements, are easy to combust and have no flame retardance, and a flame retardant is usually added in the preparation of polystyrene materials, for example, Chinese patent CN102399405B discloses a high-temperature resistant halogen-free flame-retardant polystyrene and a preparation method thereof, the temperature resistance of the halogen-free polystyrene and the flame retardant property of the halogen-free polystyrene are greatly improved by adding a wrapping red flame retardant in the polystyrene materials, and the test shows that the flame retardant effect can reach UL-945VA level, the thermal deformation 1.82MPa can reach more than 85 ℃, and the application range of the polystyrene is expanded; the invention patent adds the flame retardant into the styrene base material by a physical mixing method, and because the bonding effect between the flame retardant molecules and the polystyrene base material is weaker, the uniformity of the dispersion 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 statement, the invention provides nitrogen-phosphorus flame-retardant polystyrene and a preparation method thereof.
Disclosure of Invention
In order to solve the defects of the prior art, the invention provides nitrogen-phosphorus flame-retardant polystyrene and a preparation method thereof.
The invention aims to provide nitrogen-phosphorus flame-retardant polystyrene.
The invention also aims to provide a preparation method of the nitrogen-phosphorus flame-retardant polystyrene.
The above purpose of the invention is realized by the following technical scheme:
the preparation method of the nitrogen-phosphorus flame-retardant polystyrene comprises the following steps:
the components by weight portion are as follows: 100 parts by mass of polystyrene grafted nitrogen-phosphorus flame retardant, 5-20 parts by mass of toughening agent, 0.5-1.5 parts by mass of antioxidant and 0.5-1 part by mass of lubricant are mixed and extruded at normal temperature in a high-speed mixer until the temperature of the material is raised to 90-100 ℃ by friction heat generated by mixing, the material is discharged and cooled, the cooled mixed material is sent into a double-screw extruder to be melted and extruded, and the extruded strip material is cooled by a water tank, pulled and then enters a granulator to be granulated, so that the nitrogen-phosphorus flame-retardant polystyrene is obtained.
The toughening agent is an ethylene-octene copolymer.
The antioxidant is thiopropionate.
The lubricant is ethylene bis stearamide.
The structural formula of the polystyrene grafted nitrogen-phosphorus flame retardant is shown as the following formula (I):
wherein n is 15 to 50.
The reaction process and the preparation method of the polystyrene grafted nitrogen-phosphorus flame retardant are as follows:
the preparation method of the polystyrene grafted nitrogen-phosphorus flame retardant comprises the following steps:
1. putting ODOPB and epoxypropane into a reaction kettle according to a certain proportion, adding water, fully stirring and dissolving, adjusting the pH to 8-10 by using NaOH, reacting for 4 hours at 70-90 ℃, and passing through a column to volatilize a solvent to obtain the nitrogen-phosphorus flame retardant micromolecule.
Wherein the feeding molar ratio of ODOPB, propylene oxide and water is 1: 1.3-1.5: 50-60.
2. THF is used as solvent, carboxyl-terminated polystyrene and SOCl2Performing acyl chlorination reaction, using toluene as solvent and pyridine as acid-binding agent, and performing esterification reaction with nitrogen-phosphorus flame retardant micromolecule to obtain polystyrene grafted nitrogen-phosphorus flame retardantAnd (4) a combustion agent.
Wherein the carboxyl-terminated polystyrene and the SOCl are2The molar ratio of the phosphorus-containing flame retardant to the phosphorus-containing flame retardant is 1:10: 10.
Compared with the prior art, the invention has the following advantages and beneficial effects:
(1) the invention provides nitrogen-phosphorus flame-retardant polystyrene, which has flame retardancy by grafting a flame retardant between polystyrene molecular chains.
(2) The invention provides nitrogen-phosphorus flame-retardant polystyrene, which is connected with a flame retardant through a covalent bond, so that the polystyrene has stable and lasting flame retardance.
Drawings
FIG. 1 is a nuclear magnetic hydrogen spectrum diagram of a polystyrene 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 ODOPB (1.0mmol) and propylene oxide (1.5mmol) into a 100mL flask, placing the flask on a reactor, adding water (50mmol) to dissolve reactants, adding NaOH solution to adjust the pH to 9 under continuous stirring, raising the temperature to 80 ℃, reacting for 4 hours, passing ethyl acetate/petroleum ether (v/v ═ 1:9) through a column, drying the reaction solvent by rotary evaporation, and drying at the temperature of 45 ℃ to constant weight to obtain the nitrogen-phosphorus flame retardant micromolecule, wherein the yield is 74.5%.
Example 2
Carboxyl-terminated polystyrene (1.0mmol) and 20mL of anhydrous tetrahydrofuran THF are added into a 50mL branched flask, the branched flask is placed on a heater, after the temperature is raised to 70 ℃, SOCl is slowly dropped2(10.0mmol) and continuing the reaction for 3h after the dropwise addition, after the reaction is finished, removing SOCl by reduced pressure distillation2And THF to afford the carboxy-terminated polystyrene acylchloride product.
Adding nitrogen phosphorus flame retardant small molecules (10.0mmol) into 50ml of Schlenk bottle, Schlenk bottle was placed on a heater, 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 the phosphorus-containing flame retardant is completely dissolved, the mixture is stirred for 30min, the carboxyl-terminated polystyrene acyl chloride product dissolved in the toluene is dropwise added, the temperature is raised to 80 ℃, the reaction is continued for 2h, the product is cooled to room temperature, and after two times of continuous dissolution/precipitation circulation of the toluene/methanol, the product is dried to constant weight under vacuum at 45 ℃, so that the polystyrene grafted nitrogen-phosphorus flame retardant is obtained, and the yield is 75.1%.
Example 3
100 parts by mass of polystyrene grafted nitrogen-phosphorus flame retardant, 10 parts by mass of toughening agent, 1 part by mass of antioxidant and 1 part by mass of lubricant are mixed and extruded at normal temperature in a high-speed mixer until the friction heat generated by mixing raises the temperature of the material to 95 ℃, the material is discharged and cooled, the cooled mixed material is sent into a double-screw extruder to be melted and extruded, and the extruded strip material is cooled by a water tank and is dragged into a granulator to be granulated, so that the nitrogen-phosphorus flame-retardant polystyrene is obtained.
Example 4
80 parts by mass of polystyrene grafted nitrogen-phosphorus flame retardant, 10 parts by mass of toughening agent, 1 part by mass of antioxidant and 1 part by mass of lubricant are mixed and extruded at normal temperature in a high-speed mixer until the friction heat generated by mixing raises the temperature of the material to 95 ℃, the material is discharged and cooled, the cooled mixed material is sent into a double-screw extruder to be melted and extruded, and the extruded strip material is cooled by a water tank and is dragged into a granulator to be granulated, so that the nitrogen-phosphorus flame-retardant polystyrene is obtained.
Example 5
60 parts by mass of polystyrene grafted nitrogen-phosphorus flame retardant, 10 parts by mass of toughening agent, 1 part by mass of antioxidant and 1 part by mass of lubricant are mixed and extruded at normal temperature in a high-speed mixer until the friction heat generated by mixing raises the temperature of the material to 95 ℃, the material is discharged and cooled, the cooled mixed material is sent into a double-screw extruder to be melted and extruded, and the extruded strip material is cooled by a water tank and is dragged into a granulator to be granulated, so that the nitrogen-phosphorus flame-retardant polystyrene is obtained.
Comparative example 1
Before processing, polystyrene is dried for 12 hours in vacuum at 80 ℃, 100 parts by mass of polystyrene, 10 parts by mass of a toughening agent, 1 part by mass of a composite antioxidant and 1 part by mass of a lubricant are added on an open type heat refining machine with a double-roll temperature of 235 ℃, the materials are mixed for 10min and then uniformly discharged, the materials are hot-pressed for 10min at 240 ℃ on a flat vulcanizing machine, cold-pressed for 8min at room temperature and discharged, various standard sample strips are prepared on a universal sampling machine, and the flame retardant property test is carried out.
Comparative example 2
Before processing, polystyrene is dried for 12 hours in vacuum at 80 ℃, 80 parts by mass of polystyrene, 10 parts by mass of a toughening agent, 1 part by mass of a composite antioxidant and 1 part by mass of a lubricant are added on an open type heat refining machine with a double-roll temperature of 235 ℃, the materials are mixed for 10min and then uniformly discharged, the materials are hot-pressed for 10min at 240 ℃ on a flat vulcanizing machine, cold-pressed for 8min at room temperature and discharged, various standard sample strips are prepared on a universal sampling machine, and the flame retardant property test is carried out.
Comparative example 3
Before processing, polystyrene is dried for 12 hours in vacuum at 80 ℃, 60 parts by mass of polystyrene, 10 parts by mass of a toughening agent, 1 part by mass of a composite antioxidant and 1 part by mass of a lubricant are added on an open type heat refining machine with the double-roll temperature of 235 ℃, the materials are mixed for 10min and then uniformly discharged, the materials are hot-pressed for 10min at 240 ℃ on a flat vulcanizing machine, cold-pressed for 8min at room temperature and discharged, various standard sample strips are prepared on a universal sampling machine, and the flame retardant property test is carried out.
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 elongation at break and the tensile strength are determined according to the national standard GB/T6344-2008.
Table 1 shows the flame retardant properties of nitrogen and phosphorus flame retardant polystyrene.
| Sample (I) | LOI(％) | UL-94 | Tensile Strength (MPa) | Elongation at Break (%) |
| Example 3 | 31.3 | V-1 | 17.02 | 250.1 |
| Example 4 | 31.0 | V-1 | 17.08 | 250.6 |
| Example 5 | 30.8 | V-1 | 17.12 | 250.8 |
| Comparative example 1 | 18.2 | N.R | 15.04 | 231.5 |
| Comparative example 2 | 18.1 | N.R | 15.01 | 230.1 |
| Comparative example 3 | 18.6 | N.R | 14.97 | 229.5 |
As can be seen from Table 1, the organic micromolecules with flame retardant effect are grafted on the polystyrene polymer chain, so that the flame retardant property of the polystyrene can be obviously improved; as can be seen from comparison of data in examples 3-5 and comparative examples 1-3, the LOI of pure PS is only 18.3%, and when organic small molecules with a flame retardant effect are grafted on a polystyrene molecular chain to modify polystyrene, the LOI can reach 31.3%, so that the flame retardant property of polystyrene 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 nitrogen-phosphorus flame-retardant polystyrene is characterized in that 100 parts by mass of the polystyrene grafted nitrogen-phosphorus flame retardant, 5-20 parts by mass of the toughening agent, 0.5-1.5 parts by mass of the antioxidant and 0.5-1 part by mass of the lubricant are adopted, wherein the polystyrene grafted nitrogen-phosphorus flame retardant has a structure shown in a formula (I):
wherein n is 15 to 50.
2. The preparation method of the nitrogen-phosphorus flame-retardant polystyrene according to claim 1, which is characterized by comprising the following steps of:
100 parts by mass of polystyrene grafted nitrogen-phosphorus flame retardant, 5-20 parts by mass of toughening agent, 0.5-1.5 parts by mass of antioxidant and 0.5-1 part by mass of lubricant are mixed and extruded at normal temperature in a high-speed mixer until the temperature of the material is raised to 90-100 ℃ by friction heat generated by mixing, the material is discharged and cooled, the cooled mixed material is sent into a double-screw extruder to be melted and extruded, and the extruded strip material is cooled by a water tank, pulled and sent into a granulator to be granulated, so that the nitrogen-phosphorus flame-retardant polystyrene is obtained.
3. The nitrogen-phosphorus flame-retardant polystyrene as claimed in claim 1, wherein the preparation method of the polystyrene grafted nitrogen-phosphorus flame retardant comprises the following steps:
(1) putting ODOPB and epoxypropane into a reaction kettle according to a certain proportion, adding water, fully stirring and dissolving, adjusting the pH to 8-10 by using NaOH, reacting for 4 hours at 70-90 ℃, and passing through a column to volatilize a solvent to obtain nitrogen-phosphorus flame retardant micromolecules;
(2) THF is used as solvent, carboxyl-terminated polystyrene and SOCl2And carrying out acyl chlorination reaction, using toluene as a solvent and pyridine as an acid-binding agent, and carrying out esterification reaction with nitrogen-phosphorus flame retardant micromolecules to obtain the polystyrene grafted nitrogen-phosphorus flame retardant.
4. The nitrogen-phosphorus flame-retardant polystyrene as claimed in claim 1, wherein the toughening agent is an ethylene-octene copolymer.
5. The nitrogen-phosphorus flame-retardant polystyrene as claimed in claim 1, wherein the antioxidant is thiopropionate.
6. The nitrogen-phosphorus flame-retardant polystyrene as claimed in claim 1, wherein the lubricant is ethylene bis stearamide.
7. The nitrogen-phosphorus flame-retardant polystyrene as claimed in claim 3, wherein in the step (1), the feeding molar ratio of ODOPB, propylene oxide and water is 1: 1.3-1.5: 50-60.
8. The nitrogen-phosphorus flame-retardant polystyrene as claimed in claim 3, wherein in the step (2), the polystyrene grafted with the phosphorus-containing flame retardant is carboxyl-terminated polystyrene and SOCl2The molar ratio of the phosphorus-containing flame retardant to the phosphorus-containing flame retardant is 1:10: 10.
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116948163A (en) * | 2023-09-20 | 2023-10-27 | 山东一诺威新材料有限公司 | Dihydroxyl DOPO halogen-free flame-retardant polyether polyol, and preparation method and application thereof |
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2020
- 2020-10-16 CN CN202011111335.2A patent/CN112250959A/en not_active Withdrawn
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116948163A (en) * | 2023-09-20 | 2023-10-27 | 山东一诺威新材料有限公司 | Dihydroxyl DOPO halogen-free flame-retardant polyether polyol, and preparation method and application thereof |
| CN116948163B (en) * | 2023-09-20 | 2023-12-29 | 山东一诺威新材料有限公司 | Dihydroxyl DOPO halogen-free flame-retardant polyether polyol, and preparation method and application thereof |
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