CN107674198A - A kind of preparation method of high-viscosity polyamide 6 - Google Patents
A kind of preparation method of high-viscosity polyamide 6 Download PDFInfo
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- CN107674198A CN107674198A CN201610618063.2A CN201610618063A CN107674198A CN 107674198 A CN107674198 A CN 107674198A CN 201610618063 A CN201610618063 A CN 201610618063A CN 107674198 A CN107674198 A CN 107674198A
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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
- C08G69/00—Macromolecular compounds obtained by reactions forming a carboxylic amide link in the main chain of the macromolecule
- C08G69/02—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids
- C08G69/08—Polyamides derived from amino-carboxylic acids or from polyamines and polycarboxylic acids derived from amino-carboxylic acids
- C08G69/14—Lactams
- C08G69/16—Preparatory processes
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- Medicinal Chemistry (AREA)
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Abstract
The invention discloses a kind of preparation method of high-viscosity polyamide 6, this method passes through following several ways：Triamido end-capping reagent is added, improves terminal amino group content；Discharge pressure is improved between preceding poly- pipe and rear poly- pipe；The wet section for cutting flat；The efficiency of solid phase polycondensation during second segment is dried is improved, and reduces energy loss, is finally reached the Efficient Adhesive Promotion to polyamide 6.
Description
Technical field
The present invention relates to technical field technical field of macromolecule polymerization, more particularly to a kind of system of high-viscosity polyamide -6
Preparation Method.
Background technology
Polyamide -6 is a kind of conventional polymer raw material, and main is applied to spinning, engineering plastics field, and it is relatively viscous
Degree is generally 2.4-3.0.If polyamide -6 is applied into polymeric film art, usually require that its relative viscosity reaches 3.2-
4.0, relative viscosity substantially reflects the height of polymer relative molecular weight.
The hydrolytic polymerization production method of polyamide -6 belongs to known content,《Polyamide handbook》Pointed out in one book,
The relative molecular weight height of polyamide, influenceed by polymerization process late phase reaction content of water in system it is notable, therefore in actual production
During, the core process of manufacture high-viscosity polyamide -6 is the water in removing system, reaction is balanced to polymerisation direction
Promote.
Specific method can be the vacuum and temperature in polymerization process after improving, and prepare relative viscosity 3.0 or so
The wet section of polyamide -6, then through extracting, drying, solid phase polycondensation, by making section and high temperature inert gas convection current, removing is cut
Water in piece simultaneously promotes remaining pendant carboxylic group and amino in section further to react, and the polyamides of high relative viscosity is finally made
Amine -6 is cut into slices.Such as patent Chinese invention patent CN103834007A is cut into slices solid by the polyamide -6 for producing common process
Mutually heated in thickening tower by nitrogen, obtain Efficient Adhesive Promotion；Chinese invention patent CN102532526A passes through polyamide -6 is wet
Section, then through extracting, drying, solid phase polycondensation, by making section and high temperature inert gas convection current obtain Efficient Adhesive Promotion.
For the above method in high relative viscosity polyamide -6 of manufacture, terminal amino group content is low, is unfavorable for being dyed；
Simultaneously in the polymerization process of above-mentioned manufacture method, because melt has been provided with certain high relative viscosity in rear poly- pipe,
Shipwreck in bottom melt is to rapidly remove, in order to obtain the wet section of target viscosities, it is necessary to have condition of high vacuum degree in rear poly- pipe
And the residence time that melt is longer in rear poly- pipe, condition of high vacuum degree can aggravate the loss amount of annulation increase caprolactam,
The longer residence time can increase the possibility that melt decomposes carbonization；In the solid phase polycondensation journey of above-mentioned manufacture method, thickening effect
Rate is not high, and for polyamide -6 of target relative viscosity are made, the required residence time is longer, and energy consumption is higher, cuts into slices by thermal oxidation
The possibility that can decline also accordingly improves.
The content of the invention
In order to solve the above technical problems, the present invention provides a kind of technical side of continuous polymerization manufacture high-viscosity polyamide -6
Case, concrete scheme are：
A kind of preparation method of high-viscosity polyamide -6, comprises the following steps：
A, raw material is prepared：By solid, oneself interior acyl is that amine puts into molten-bath through pulverizer, is molten into the liquid that temperature is 110-130 DEG C
Caprolactam, liquid caprolactam and end-capping reagent A injection pans are well mixed, after being preheated to 160-180 DEG C, through preheating
Device injects pre-polymerization pipe after being heated to 200-220 DEG C；
B, pre-polymerization：End-capping reagent the B aqueous solution or aqueous dispersion is added dropwise in polymerization pipe forward, pre-polymerization pipe carries upper, middle and lower three
The separate heating system of section, it is 230-250 DEG C to control epimere temperature, stage casing temperature is 240-260 DEG C, hypomere temperature is
220-240 DEG C, it is 0.15-0.3MPa to control pre-polymerization pipe internal pressure；
C, melt conveying：Melt from pre-polymerization bottom of the tube by gear pump through pipeline pressurized delivered the polymerization pipe after, conveyance conduit
Exist conical baffled below outlet in rear polymerization pipe, the vertical range in gap is 8-15mm between baffle plate and outlet；
D, rear polymerization：For polymerization pipe with the separate heating system of upper, middle and lower segment, it is 220-240 to control epimere temperature afterwards
DEG C, stage casing temperature be 240-250 DEG C, hypomere temperature be 250-260 DEG C；
E, Cast Strip and pelletizing：Melt is delivered to end of extruded band through fondant filter and is extruded as cylindric melt from rear polymerization bottom of the tube
Bar, cooled down after a pair roller extruding is flat by cold water, through pelleter pelletizing, obtain flaky particles；
F, extract：Particle enters pre-extracted water pot through vibratory sieve, and it is 95-105 DEG C to control pre-extracted coolant-temperature gage, and particle is in pre-extracted
It is delivered to after stopping 8-16h in water pot by slush pump in extraction tower, extraction tower reclaimed water temperature control is made as 90-130 DEG C, and particle stops
After dewaterer dehydration is delivered to after 12-16h, one section of drying tower is sent into；
G, drying and solid phase polycondensation：One section of drying tower top nitrogen temperature control is 100-125 DEG C, and nitrogen temperature control in bottom is
110-120 DEG C, enter two-stage drying tower after buffered tank；The nitrogen temperature control of two-stage drying tower top is 135-145 DEG C, bottom
Nitrogen temperature control is 125-135 DEG C, and cooling feed bin is entered after buffered tank.
Preferably, in described step A, end-capping reagent A is 1,3,5- triaminobenzenes or diethylenetriamines or 4,4,4- tri-
Triaminotriphenyl-methane.
Preferably, in described step B, the end-capping reagent B is benzoic acid or terephthalic acid (TPA) or naphthoic acid or 1,5- naphthalene
Dioctyl phthalate.
Preferably, in described step C, the melt pressure after gear pump is 0.8-1.2Mpa.
Preferably, in described step D, it is -0.05-0Mpa to control pre-polymerization pipe internal pressure.
Preferably, in described step E, the thickness of the flaky particles of gained is 1.4-1.6mm.
Preferably, in described step G, drying tower includes one section of drying tower, surge tank, two-stage drying tower, one section of drying
Tower, two-stage drying tower each are equipped with independent nitrogen circulating system.
Beneficial effects of the present invention are compared with prior art：
1. adding triamido end-capping reagent, terminal amino group content is improved；
2. improving discharge pressure between preceding poly- pipe and rear poly- pipe, rear poly- tube inlet carries flash distillation plant, can quickly improve viscosity；
3. roll is carried between end of extruded band and water cooling, the wet section that can cut flat, beneficial to extraction and solid-phase tack producing；
4. drying tower is divided into two sections, every section all carries two air inlets, and first paragraph carries out surface drying to section after extraction, can improved
The efficiency of solid phase polycondensation during second segment is dried, and reduce energy loss.
Embodiment
With reference to embodiment, the embodiment of the present invention is described in further detail.Following examples are used for
Illustrate the present invention, but be not limited to the scope of the present invention.
A kind of preparation method of high-viscosity polyamide -6, comprises the following steps：
A, raw material is prepared：Solid caprolactam is put into molten-bath through pulverizer, is molten into liquid that temperature is 120 DEG C acyl in oneself
Amine, liquid caprolactam and end-capping reagent A injection pans are well mixed, after being preheated to 165 DEG C, are heated to through pre-heater
Pre-polymerization pipe is injected after 205 DEG C, the end-capping reagent A is diethylenetriamines；
B, pre-polymerization：End-capping reagent the B aqueous solution or aqueous dispersion is added dropwise in polymerization pipe forward, pre-polymerization pipe carries upper, middle and lower three
The separate heating system of section, it is 240 DEG C to control epimere temperature, stage casing temperature is 250 DEG C, hypomere temperature is 235 DEG C, control
Pre-polymerization pipe internal pressure is 0.2MPa, and the end-capping reagent B is benzoic acid；
C, melt conveying：Melt from pre-polymerization bottom of the tube, by gear pump, through pipeline pressurized delivered, pass through by the polymerization pipe after, control
Melt pressure after gear pump is 1.0MPa, conveyance conduit exist below the outlet in rear polymerization pipe it is conical baffled, baffle plate with
The vertical range in gap is 12mm between outlet；
D, rear polymerization：Polymerization pipe is with the separate heating system of upper, middle and lower segment afterwards, control epimere temperature be 230 DEG C,
Stage casing temperature is 245 DEG C, hypomere temperature is 255 DEG C, and it is normal pressure to control pre-polymerization pipe internal pressure；
E, Cast Strip and pelletizing：Melt is delivered to end of extruded band through fondant filter and is extruded as cylindric melt from rear polymerization bottom of the tube
Bar, cooled down after a pair roller extruding is flat by cold water, through pelleter pelletizing, obtain thickness 1.5mm flaky particles；
F, extract：Particle enters pre-extracted water pot through vibratory sieve, and it is 100 DEG C to control pre-extracted coolant-temperature gage, and particle is in pre-extracted water
It is delivered to after stopping 10h in tank by slush pump in extraction tower, extraction tower reclaimed water temperature control is made as 120 DEG C, and particle conveys after stopping 14h
After being dehydrated to dewaterer, one section of drying tower is sent into；
G, drying and solid phase polycondensation：One section of drying tower top nitrogen temperature control is 125 DEG C, and nitrogen temperature control in bottom is 110
DEG C, water vapour content is 500-800ppm, oxygen content 3-5ml/L in nitrogen, and after section stops 9 hours, buffered tank is laggard
Enter two-stage drying tower；The nitrogen temperature control of two-stage drying tower top is 140 DEG C, and nitrogen temperature control in bottom is 135 DEG C, in nitrogen
Water vapour content is 80-100ppm, oxygen content 200-500ppm, and cooling material is entered after section stops 5 hours, after buffered tank
Storehouse.
Major parameter in each specific embodiment is see following table：
| End-capping reagent A | End-capping reagent B | Melt pressure | Particle thickness | |
| Embodiment 1 | Diethylenetriamines | Benzoic acid | 1.0Mpa | 1.5mm |
| Embodiment 2 | Diethylenetriamines | 1,5- naphthalenedicarboxylic acids | 1.2Mpa | 1.4mm |
| Embodiment 3 | 1,3,5- triaminobenzenes | Naphthoic acid | 0.8Mpa | 1.5mm |
| Embodiment 4 | 4,4,4- triaminotriphenyl-methanes | 1,5- naphthalenedicarboxylic acids | 0.9Mpa | 1.6mm |
After tested, the relative viscosity of each embodiment is as follows：
| Embodiment 1 | Embodiment 2 | Embodiment 3 | Embodiment 4 | |
| Relative viscosity | 4.31 | 4.25 | 4.08 | 4.12 |
Described above is only the preferred embodiment of the present invention, it is noted that is come for those skilled in the art
Say, without departing from the technical principles of the invention, some improvement and modification can also be made, these improvement and modification also should
It is considered as protection scope of the present invention.
Claims (8)
1. a kind of preparation method of high-viscosity polyamide -6, it is characterised in that comprise the following steps：
A, raw material is prepared：By solid, oneself interior acyl is that amine puts into molten-bath through pulverizer, is molten into the liquid that temperature is 110-130 DEG C
Caprolactam, liquid caprolactam and end-capping reagent A injection pans are well mixed, after being preheated to 160-180 DEG C, through preheating
Device injects pre-polymerization pipe after being heated to 200-220 DEG C；
B, pre-polymerization：End-capping reagent the B aqueous solution or aqueous dispersion is added dropwise in polymerization pipe forward, pre-polymerization pipe carries upper, middle and lower three
The separate heating system of section, it is 230-250 DEG C to control epimere temperature, stage casing temperature is 240-260 DEG C, hypomere temperature is
220-240 DEG C, it is 0.15-0.3MPa to control pre-polymerization pipe internal pressure；
C, melt conveying：Melt from pre-polymerization bottom of the tube by gear pump through pipeline pressurized delivered the polymerization pipe after, conveyance conduit
Exist conical baffled below outlet in rear polymerization pipe, the vertical range in gap is 8-15mm between baffle plate and outlet；
D, rear polymerization：For polymerization pipe with the separate heating system of upper, middle and lower segment, it is 220-240 to control epimere temperature afterwards
DEG C, stage casing temperature be 240-250 DEG C, hypomere temperature be 250-260 DEG C；
E, Cast Strip and pelletizing：Melt is delivered to end of extruded band through fondant filter and is extruded as cylindric melt from rear polymerization bottom of the tube
Bar, cooled down after a pair roller extruding is flat by cold water, through pelleter pelletizing, obtain flaky particles；
F, extract：Particle enters pre-extracted water pot through vibratory sieve, and it is 95-105 DEG C to control pre-extracted coolant-temperature gage, and particle is in pre-extracted
It is delivered to after stopping 8-16h in water pot by slush pump in extraction tower, extraction tower reclaimed water temperature control is made as 90-130 DEG C, and particle stops
After dewaterer dehydration is delivered to after 12-16h, one section of drying tower is sent into；
G, drying and solid phase polycondensation：One section of drying tower top nitrogen temperature control is 100-125 DEG C, and nitrogen temperature control in bottom is
110-120 DEG C, enter two-stage drying tower after buffered tank；The nitrogen temperature control of two-stage drying tower top is 135-145 DEG C, bottom
Nitrogen temperature control is 125-135 DEG C, and cooling feed bin is entered after buffered tank.
2. the preparation method of high-viscosity polyamide -6 as claimed in claim 1, it is characterised in that in described step A, end-blocking
Agent A is 1,3,5- triaminobenzenes or diethylenetriamines or 4,4,4- triaminotriphenyl-methanes.
3. the preparation method of high-viscosity polyamide -6 as claimed in claim 1, it is characterised in that described in described step B
End-capping reagent B is benzoic acid or terephthalic acid (TPA) or naphthoic acid or 1,5- naphthalenedicarboxylic acids.
4. the preparation method of high-viscosity polyamide -6 as claimed in claim 1, it is characterised in that in described step C, pass through
Melt pressure after gear pump is 0.8-1.2Mpa.
5. the preparation method of high-viscosity polyamide -6 as claimed in claim 1, it is characterised in that in described step D, control
Pre-polymerization pipe internal pressure is -0.05-0Mpa.
6. the preparation method of high-viscosity polyamide -6 as claimed in claim 1, it is characterised in that in described step E, gained
The thickness of flaky particles be 1.4-1.6mm.
7. the preparation method of high-viscosity polyamide -6 as claimed in claim 1, it is characterised in that in described step G, dry
Tower includes one section of drying tower, surge tank, two-stage drying tower, and one section of drying tower, two-stage drying tower each are equipped with independent nitrogen and followed
Loop system.
8. the preparation method of high-viscosity polyamide -6 as claimed in claim 1, it is characterised in that comprise the following steps：
A, raw material is prepared：Solid caprolactam is put into molten-bath through pulverizer, is molten into liquid that temperature is 120 DEG C acyl in oneself
Amine, liquid caprolactam and end-capping reagent A injection pans are well mixed, after being preheated to 165 DEG C, are heated to through pre-heater
Pre-polymerization pipe is injected after 205 DEG C, the end-capping reagent A is diethylenetriamines；
B, pre-polymerization：End-capping reagent the B aqueous solution or aqueous dispersion is added dropwise in polymerization pipe forward, pre-polymerization pipe carries upper, middle and lower three
The separate heating system of section, it is 240 DEG C to control epimere temperature, stage casing temperature is 250 DEG C, hypomere temperature is 235 DEG C, control
Pre-polymerization pipe internal pressure is 0.2MPa, and the end-capping reagent B is benzoic acid；
C, melt conveying：Melt from pre-polymerization bottom of the tube, by gear pump, through pipeline pressurized delivered, pass through by the polymerization pipe after, control
Melt pressure after gear pump is 1.0MPa, conveyance conduit exist below the outlet in rear polymerization pipe it is conical baffled, baffle plate with
The vertical range in gap is 12mm between outlet；
D, rear polymerization：Polymerization pipe is with the separate heating system of upper, middle and lower segment afterwards, control epimere temperature be 230 DEG C,
Stage casing temperature is 245 DEG C, hypomere temperature is 255 DEG C, and it is normal pressure to control pre-polymerization pipe internal pressure；
E, Cast Strip and pelletizing：Melt is delivered to end of extruded band through fondant filter and is extruded as cylindric melt from rear polymerization bottom of the tube
Bar, cooled down after a pair roller extruding is flat by cold water, through pelleter pelletizing, obtain thickness 1.5mm flaky particles；
F, extract：Particle enters pre-extracted water pot through vibratory sieve, and it is 100 DEG C to control pre-extracted coolant-temperature gage, and particle is in pre-extracted water
It is delivered to after stopping 10h in tank by slush pump in extraction tower, extraction tower reclaimed water temperature control is made as 120 DEG C, and particle conveys after stopping 14h
After being dehydrated to dewaterer, one section of drying tower is sent into；
G, drying and solid phase polycondensation：One section of drying tower top nitrogen temperature control is 125 DEG C, and nitrogen temperature control in bottom is 110
DEG C, water vapour content is 500-800ppm, oxygen content 3-5ml/L in nitrogen, and after section stops 9 hours, buffered tank is laggard
Enter two-stage drying tower；The nitrogen temperature control of two-stage drying tower top is 140 DEG C, and nitrogen temperature control in bottom is 135 DEG C, in nitrogen
Water vapour content is 80-100ppm, oxygen content 200-500ppm, and cooling material is entered after section stops 5 hours, after buffered tank
Storehouse.
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| CN201610618063.2A CN107674198A (en) | 2016-08-01 | 2016-08-01 | A kind of preparation method of high-viscosity polyamide 6 |
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| CN201610618063.2A CN107674198A (en) | 2016-08-01 | 2016-08-01 | A kind of preparation method of high-viscosity polyamide 6 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108822290A (en) * | 2018-07-30 | 2018-11-16 | 江苏百利达股份有限公司 | A kind of preparation system and method for high viscosity nylon 6 slice |
| CN110437609A (en) * | 2018-05-04 | 2019-11-12 | 江苏瑞美福实业有限公司 | A kind of high flow flame-proof polyamide 6 and preparation method thereof |
| WO2022042565A1 (en) * | 2020-08-31 | 2022-03-03 | 聊城鲁西聚酰胺新材料科技有限公司 | Nylon 6 production process, system, and product |
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| CN102532526A (en) * | 2011-11-29 | 2012-07-04 | 湖南岳化化工股份有限公司 | Continuous polymerization production process of high-viscosity polyamide 6 |
| CN102911366A (en) * | 2012-11-13 | 2013-02-06 | 天津工业大学 | Preparation method of nylon 6 having high hygroscopicity, high dyeing property and high elasticity |
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- 2016-08-01 CN CN201610618063.2A patent/CN107674198A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102532526A (en) * | 2011-11-29 | 2012-07-04 | 湖南岳化化工股份有限公司 | Continuous polymerization production process of high-viscosity polyamide 6 |
| CN102911366A (en) * | 2012-11-13 | 2013-02-06 | 天津工业大学 | Preparation method of nylon 6 having high hygroscopicity, high dyeing property and high elasticity |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110437609A (en) * | 2018-05-04 | 2019-11-12 | 江苏瑞美福实业有限公司 | A kind of high flow flame-proof polyamide 6 and preparation method thereof |
| CN108822290A (en) * | 2018-07-30 | 2018-11-16 | 江苏百利达股份有限公司 | A kind of preparation system and method for high viscosity nylon 6 slice |
| WO2022042565A1 (en) * | 2020-08-31 | 2022-03-03 | 聊城鲁西聚酰胺新材料科技有限公司 | Nylon 6 production process, system, and product |
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