CN109054081A - Novel nitrogen phosphorus synergistic flame retardant and preparation method thereof - Google Patents
Novel nitrogen phosphorus synergistic flame retardant and preparation method thereof Download PDFInfo
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- CN109054081A CN109054081A CN201810612912.2A CN201810612912A CN109054081A CN 109054081 A CN109054081 A CN 109054081A CN 201810612912 A CN201810612912 A CN 201810612912A CN 109054081 A CN109054081 A CN 109054081A
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- 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
- C08K5/00—Use of organic ingredients
- C08K5/16—Nitrogen-containing compounds
- C08K5/34—Heterocyclic compounds having nitrogen in the ring
- C08K5/3467—Heterocyclic compounds having nitrogen in the ring having more than two nitrogen atoms in the ring
- C08K5/3477—Six-membered rings
- C08K5/3492—Triazines
- C08K5/34928—Salts
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D251/00—Heterocyclic compounds containing 1,3,5-triazine rings
- C07D251/02—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings
- C07D251/12—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members
- C07D251/26—Heterocyclic compounds containing 1,3,5-triazine rings not condensed with other rings having three double bonds between ring members or between ring members and non-ring members with only hetero atoms directly attached to ring carbon atoms
- C07D251/40—Nitrogen atoms
- C07D251/54—Three nitrogen atoms
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Abstract
The invention discloses a kind of novel nitrogen phosphorus synergistic flame retardants and preparation method thereof, existing fire retardant phosphorus nitrogen content proportional imbalance, affect flame retardant property when they are used alone, to increase its additive amount, the present invention is made by following steps: (1) melamine and urea are in the equipment with temperature control, mixed function, it is reacted under heating, stirring condition, between 160 DEG C -220 DEG C of reaction temperature, reaction time 1-2 hour；Polyphosphoric acid and ammonium phosphate salt are added in (2) (1) step products, controls reaction temperature between 240 DEG C -300 DEG C, reacts 1-3 hours, cooling obtains nitrogen phosphorus synergistic flame retardant finished product.The fire retardant has thermal stability good, and phosphorus nitrogen content is adjustable, makes it that can show optimal phosphorus phosphorus-nitrogen coordinated fire-retardant performance in different polymer.Technical process process is short, easy to operate, safety, raw material high income, easily realizes industrialization.
Description
Technical field
The invention belongs to chemical technology fields, are related to novel nitrogen phosphorus synergistic flame retardant and preparation method thereof.
Background technique
Although traditional halogenated flame retardant is since its excellent flame retarding efficiency is widely used, with its fire-retardant height
Polymers can be generated when on fire a large amount of smog and it is toxic, there is corrosive hydrogen halide, the life of environment and people is pacified
It damages entirely.And the high polymer of the based flame retardant containing halogen can generate the evil of carcinogen two during subsequent recycling and reusing
English pollutes the environment.Therefore, European Union puts into effect the use of the multi-sections such as WEEE, ROHS instruction limitation halogenated flame retardant in succession, and
Also it has issued " electronics and IT products pollution control management method " and the use of halogenated flame retardant has been limited in China.Fire retardant is non-
The requirement of halogenation is more more and more urgent.P-N type fire retardant shows good resistance based on collaboration and synergistic effect between phosphorus-nitrogen
Performance is fired, but also has many advantages, such as that environmental-friendly, low cigarette, low toxicity become one of research hotspot.
In fire retardant phosphorus nitrogen content number with flame retardant property have direct influence, reasonable phosphorus nitrogen content ratio can more be sent out
Wave the effect of phosphorus nitrogen synergistic.What is be most widely used in phosphorus phosphorus-nitrogen coordinated fire-retardant agent is long-chain polyphosphoric acid ammonium (II type of APP) and poly- phosphorus
Sour melamine salt (MPP).However, ammonium polyphosphate theory phosphorus content is 32% or so, nitrogen content is 14% or so, it is low-phosphorous in nitrogen
It is high；In polyphosphoric acid melamine salt theoretical phosphorus content be 15%, nitrogen content 41%, it is low in nitrogen high phosphorus.Their phosphorus nitrogen content
Proportional imbalance affects flame retardant property when they are used alone, to increase its additive amount, and then affects polymer
Mechanical mechanics property etc. limits their application range.And APP decomposition temperature is low, thermal stability is poor, fits it mainly
For the fire-retardant of the low processing temperatures polymer such as polyethylene, polypropylene, polyurethane, epoxy resin, and cannot be used for PA it is contour plus
The polymer of work temperature makes its application range receive very big limitation.Document " Ou Yuxiang etc., the expansion of polyphosphoric acid melamine system
The burning behavior of fire retardant PA6 and thermal cracking research, Chinese Plastics, 2003,17(11): in 61-64 " using MPP or
The ternary expanding fire retardant flame-proof PA 6 that MPP is constituted, when MPP additive amount is 25% only up to UL94 V-1 grades of flame retardant rating.Therefore,
The application of APP, MPP are compounded together with other fire retardants mostly at this stage, to reach optimal flame retardant effect.Document
" Li Liping, Shandong build new etc., the flame retardant property of the fire-retardant pure cotton fabric of APP/MPP/PER, Tianjin Polytechnic University's journal, and volume 30 the 2nd
Phase describes in 2011:54-56 " and carries out fire-retardant flame retardant property to cotton fabric using APP, APP/MPP and compare, as the result is shown
When APP/MPP ratio is in 10:7 with the flame retardant property more excellent than simple APP, phosphorus nitrogen content is respectively 25% He at that time
30.5%.Describing in United States Patent (USP) US4966931 uses cyanurotriamide modified ammonium polyphosphate and melamine as selection agent
The fire retardant of polypropylene flame redardant or polyethylene.CN01128575 is described with pentaerythritol phosphate and melamine polyphosphate
Compounding prepares polyolefin halogen-free expansion fire retardant.
The synergistic effect of phosphorus nitrogen cannot be played very well in view of APP and MPP fire retardant monomer phosphorus nitrogen content proportionate relationship.And
It when obtaining preferable phosphorus nitrogen content, since APP thermal stability is poor, limits it according to the mode of APP and MPP mixture and answers
It is extremely limited with range.Preparing the reasonable fire retardant of phosphorus nitrogen content ratio is also one of research hotspot.Chinese patent
CN200510049426.7 is proposed to be contained using phosphorus pentoxide, ammonium dihydrogen phosphate, melamine or morpholine or piperazine or alkyl
Hydroxy polyamine preparation has
Wherein M is melamine group or morpholine group or piperidines group or piperazine group or alkyl hydroxyl polyamine group etc..n
The fire retardant of 1000 structure of+m >, however from the point of view of its preparation process and embodiment description, essence is to prepare relatively rationally
Phosphorus-nitrogen ratio or fire proofing with expansion character, to improve the related flame retardant property of Quadrafos.
Summary of the invention
For the disadvantage that phosphorus nitrogen content ratio in the phosphor nitrogen combustion inhibitors such as APP, MPP is uncoordinated, the invention proposes a kind of phosphorus
Nitrogen content ratio is adjustable, with the novel phosphor nitrogen synergistic flame retardant and its technology of preparing compared with strength polymer adaptability.
In order to achieve the above objectives, the present invention uses following technological means: the nitrogen phosphorus synergistic flame retardant has following molecular formula:
(NH4)xM(1-x)PO3
M represents melamine in formula, and x is between 0-1.
The nitrogen phosphorus synergistic flame retardant is made by the steps:
(1) melamine and urea react under heating, stirring condition in the equipment with temperature control, mixed function, control reaction
Temperature is between 160 DEG C -220 DEG C, reaction time 1-2 hour；
(2) in the equipment with temperature control, mixed function, under heating, stirring condition, polyphosphoric acid is added in (1) step product
And the ammonium phosphate salt that (3) step obtains, reaction temperature is controlled between 240 DEG C -300 DEG C, is reacted 1-3 hours, cooling nitrogen phosphorus
Synergistic flame retardant finished product；
(3) ammonia overflowed in (1), (2) step reaction process is absorbed using phosphoric acid, ammonium phosphate salt is obtained, as anti-
Raw material is answered to be added in the reaction of (2) step.
In the present invention, the equipment with temperature control, mixed function can be using spiral ribbon mixer, mixer either kneader
Deng.
The mole ratio of urea and melamine is 1:1-4:1 in (1) step reaction of the invention, what (2) step was added
The molar ratio of polyphosphoric acid and ammonium phosphate salt is 1:1-3:1, the ammonium phosphate being added by adjusting melamine and urea, (2) step
The tandem product of different nitrogen and phosphorus contents can be obtained in the ratio of salt.
In the present invention, the concentration for the polyphosphoric acid that (2) step is added is in 105%-110%.Polyphosphoric acid concentration height facilitates instead
It answers and the quality of final finished, but its preparation is difficult, price is higher, reduces the economy of technique；Polyphosphoric acid concentration is too low, instead
Due to there is the presence of free phosphoric acid during answering, the corrosion of equipment is increased, and finished product polymerization needs to remove more moisture,
Energy consumption is increased, what is obtained is final lower at the product degree of polymerization, and pH value reduces, and solubility increases, and flame retardant property is poor.
In the present invention, (1) reaction temperature is 160 DEG C -220 DEG C, preferably at 180-200 DEG C, reaction time 1-2 hour,
Preferably 1-1.5 hours.(2) step reaction temperature is 240 DEG C -300 DEG C, preferably at 280-300 DEG C, reaction time 1-3 hour,
Preferably 2-3 hours.The lower finished product degree of polymerization of temperature is low, and flame retardant property reduces；The excessively high finished product of temperature decomposites ammonia, reduces
The nitrogen content of finished product, reduces flame retardant property.Reaction time is few, and the degree of polymerization is low, and anti-flammability reduces；Reaction time is long, finished product point
Solution, ammonia overflow, and reduce the nitrogen content and flame retardant property of finished product.
Phosphorus phosphorus-nitrogen coordinated fire-retardant agent of the invention has thermal stability good, and phosphorus nitrogen content is adjustable, makes it in different polymer
Optimal phosphorus phosphorus-nitrogen coordinated fire-retardant performance can be shown.Technical process process is short, easy to operate, safety, raw material high income, Yi Shi
Now industrialize.
Detailed description of the invention
Fig. 1 is fire retardant preparation flow of the present invention.
Specific embodiment
Protection content of the invention, is described in detail, by specific embodiment for what is be specifically discussed in detail
Embodiment only belongs to an example in range defined in the claims, is only used for specific example, not representation
Sharp claim full scope claimed.
The step of all embodiments (2), carries out in 20 liters of kneaders of jacketed, is carried out in collet using conduction oil
Temperature detection display device is arranged in heating；Kneader is cooling using the cooling indirect type of cooling of conduction oil.Gas use is overflowed in reaction
It is absorbed after roots blower pressurization through two concatenated absorbers that phosphoric acid solution, bottom are provided with phosphate ammonium salt discharge gate
After empty, absorb liquid and use condensing crystallizing, obtain ammonium phosphate salt, crystalline mother solution is used as absorbing liquid after mixing with phosphoric acid.
The following raw material is used in all embodiments:
Urea, Yunnan Yuntianhua Co., Ltd., total nitrogen content >=46.4%.
Melamine, Sichuan Golden Elephant Chemical Co., Ltd, content 99.8%.
Industrial phosphoric acid, Yunnan Jianglin Group Co., Ltd.'s production, concentration 85%.
Polyphosphoric acid is made by oneself using the phosphorus pentoxide and industrial phosphoric acid of Yunnan Jianglin Group Co., Ltd.'s production, dense
Degree is respectively 105%, 110%.
The method that the final products phosphorus phosphorus-nitrogen coordinated fire-retardant agent constituent analysis that embodiment obtains is taken:
Prepared by the analyzing liquid sample of final products: accurately weighing 2 grams of final products, be accurate to 0.0002 gram, be placed in 100 milliliters of beakers
In, 20 milliliters of distilled water and 5 milliliters of perchloric acid are added, after sample is completely dissolved, are heated to driving extra perchloric acid out of, it is cooling, it moves
Into 500 milliliters of volumetric flasks, adds 10 milliliters of hydrochloric acid, be diluted with water to scale, shake up.Measurement for product phosphorus, nitrogen content.
The analysis of phosphorus content in final products: pipetting 10 milliliters of sample liquids, according to " phosphorus pentoxide contains in inorganic chemical product
Measuring fixed universal method " method specified in (GB/T 23843-2009) analyzed；
The analysis of nitrogen content in final products: pipetting 100 milliliters of sample liquid, by " what total nitrogen content measured in inorganic chemical product is logical
With method distillation-acid-base titration " method specified in (GB/T 23952-2009) analyzed.
In embodiment, the analysis of final products physical and chemical index:
PH value measurement: accurately weighing 10.0 grams of final products in 200 milliliters of beakers, and 90 milliliters of distilled water are added, and stirs 30 points
Clock, the PHSJ-4A type laboratory PH meter measurement pH produced with Shanghai INESA Scientific Instrument Co., Ltd..
Water solubility analysis: in Example, 10.0 grams of final powder product is placed in 200 milliliters of beakers, is added 90 grams
Distilled water stirs 30 minutes at room temperature, be pre-dried, the 4# sand core funnel of constant weight is filtered, dry, weighing calculates
Solubility.
Thermal decomposition temperature measurement: taking about 10 milligrams of final products to be placed in crucible, raw using the permanent scientific instrument factory in Beijing
The HTG-1 type microcomputer differential thermal balance of production is risen under the conditions of 700 DEG C from room temperature with 10 DEG C of temperature rises and is measured in air environment.To lose
Temperature when weighing 2% determines the thermal stability of product.
Embodiment 1
2400 grams of urea and 2520 grams of melamines are put into kneader, under stirring condition, are warming up to 180 DEG C, reaction 1.5 is small
When, the polyphosphoric acid of 7127 grams of concentration 110% is added, is warming up to 280 DEG C, reacts 2.5 hours, cooling obtains 9940 grams of phosphorus nitrogen synergistics
Fire retardant finished product.Reaction is overflowed gas and is emptied after roots blower pressurization is absorbed using the phosphoric acid solution of 2000 grams of concentration 85%, inhales
It receives the concentrated crystallization of liquid and obtains 2000 grams of ammonium phosphate salts.Finished product detection the results are shown in Table 1.
Embodiment 2
1800 grams of urea and 2520 grams of melamines are put into kneader, under stirring condition, are warming up to 200 DEG C and are reacted 1 hour, add
Enter 5890 gram 105% polyphosphoric acid and embodiment 1 obtained in 2000 grams of ammonium phosphate salts, be warming up to 300 DEG C, react 2 hours, it is cold
But 10550 grams of phosphorus phosphorus-nitrogen coordinated fire-retardant agent finished products are obtained.Reaction overflows gas after roots blower pressurizes, and mother is concentrated with embodiment 1
The phosphoric acid mixed liquor that 2310 grams of concentration are 85% is added in liquid to be absorbed, absorbing liquid crystallizes to obtain 2300 grams of ammonium phosphate salts.Finished product
Testing result is shown in Table 1.
Embodiment 3
600 grams of urea and 5040 grams of melamines are put into kneader, under stirring condition, are warming up to 160 DEG C and are reacted 1.5 hours,
2300 grams of ammonium phosphate salts obtained in the polyphosphoric acid and embodiment 2 of 5345 gram 110% of addition, are warming up to 300 DEG C, react 3 hours,
Cooling obtains 12330 grams of phosphorus phosphorus-nitrogen coordinated fire-retardant agent finished products.Reaction overflows gas after roots blower pressurizes, and is concentrated with embodiment 2
The phosphoric acid mixed liquor that 1500 grams of concentration are 85% is added in mother liquor to be absorbed, absorbing liquid crystallizes to obtain 1610 grams of ammonium phosphate salts.At
Product examine survey the results are shown in Table 1.
Embodiment 4
600 grams of urea and 5040 grams of melamines are put into kneader, under stirring condition, are warming up to 180 DEG C, are reacted 1 hour, add
Enter 6250 gram 105% polyphosphoric acid and embodiment 3 obtained in 1610 grams of ammonium phosphate salts, maintain 300 DEG C of temperature, react 2.5 hours
Afterwards, cooling obtains 12410 grams of phosphorus phosphorus-nitrogen coordinated fire-retardant agent finished products.Reaction overflows gas after roots blower pressurizes, dense with embodiment 3
The phosphoric acid mixed liquor that 2000 grams of concentration are 85% is added in contracting mother liquor to be absorbed, 2040 grams of ammonium phosphate salts are obtained.Finished product detection knot
Fruit is shown in Table 1.
1 embodiment of table analyzes result
Claims (9)
1. novel nitrogen phosphorus synergistic flame retardant, it is characterised in that: the fire retardant has following molecular formula:
(NH4)xM(1-x)PO3
M represents melamine in formula, and x is between 0-1.
2. the preparation method of novel nitrogen phosphorus synergistic flame retardant as described in claim 1, it is characterised in that: the product is by following steps
It is made:
(1) melamine and urea react, reaction temperature in the equipment with temperature control, mixed function under heating, stirring condition
Between 160 DEG C -220 DEG C, reaction time 1-2 hour；
(2) in the equipment with temperature control, mixed function, under heating, stirring condition, polyphosphoric acid is added in (1) step product
And the ammonium phosphate salt that (3) step obtains, reaction temperature is controlled between 240 DEG C -300 DEG C, is reacted 1-3 hours, and cooling obtains nitrogen
Phosphorus synergistic flame retardant finished product；
(3) ammonia overflowed in (1), (2) step reaction process is absorbed using phosphoric acid, ammonium phosphate salt is obtained, as anti-
Raw material is answered to be added in next batch reaction (2) step reaction.
3. the preparation method of novel nitrogen phosphorus synergistic flame retardant as claimed in claim 2, it is characterised in that: step (1) and (2) are anti-
Ying Jike is completed in the same device, can also successively be completed in distinct device respectively.
4. the preparation method of novel nitrogen phosphorus synergistic flame retardant as claimed in claim 3, it is characterised in that: band temperature control, mixing function
The equipment of energy is spiral ribbon mixer, mixer either kneader.
5. the preparation method of novel nitrogen phosphorus synergistic flame retardant as claimed in claim 2, it is characterised in that: in the reaction of (1) step
The molar ratio of urea and melamine is 1:1-4:1.
6. the preparation method of the novel nitrogen phosphorus synergistic flame retardant as described in claim 2 or 5, it is characterised in that: the reaction of (2) step
The molar ratio of middle polyphosphoric acid and ammonium phosphate salt is 1:1-3:1.
7. the preparation method of novel nitrogen phosphorus synergistic flame retardant as claimed in claim 2, it is characterised in that: (2) step is added
Polyphosphoric acid concentration in 105%-110%.
8. the preparation method of novel nitrogen phosphorus synergistic flame retardant as claimed in claim 2, it is characterised in that: (1) step reaction temperature
For degree at 180-200 DEG C, the reaction time is 1-1.5 hours.
9. the preparation method of novel nitrogen phosphorus synergistic flame retardant as claimed in claim 2, it is characterised in that: (2) step reaction temperature
Degree is 280-300 DEG C, and the reaction time is 2-3 hours.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101891170A (en) * | 2010-07-12 | 2010-11-24 | 华东理工大学 | Method for preparing crystallized V-shaped ammonium polyphosphate with stable crystal form |
| CN102659699A (en) * | 2012-04-08 | 2012-09-12 | 刘方旭 | Efficient nitrogen-phosphorus fire retardant and preparation method thereof |
| CN102674287A (en) * | 2012-04-28 | 2012-09-19 | 南通紫鑫实业有限公司 | Method for producing ammonium polyphosphate flame retardant by utilizing melamine tail gas |
| CN104647538A (en) * | 2013-11-22 | 2015-05-27 | 高天红 | Multifunctional low-cost timber fire retardant and preparation method thereof |
-
2018
- 2018-06-14 CN CN201810612912.2A patent/CN109054081B/en active Active
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101891170A (en) * | 2010-07-12 | 2010-11-24 | 华东理工大学 | Method for preparing crystallized V-shaped ammonium polyphosphate with stable crystal form |
| CN102659699A (en) * | 2012-04-08 | 2012-09-12 | 刘方旭 | Efficient nitrogen-phosphorus fire retardant and preparation method thereof |
| CN102674287A (en) * | 2012-04-28 | 2012-09-19 | 南通紫鑫实业有限公司 | Method for producing ammonium polyphosphate flame retardant by utilizing melamine tail gas |
| CN104647538A (en) * | 2013-11-22 | 2015-05-27 | 高天红 | Multifunctional low-cost timber fire retardant and preparation method thereof |
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