CN107972297A - A kind of continuous preparation method of high power polypropylene foamed plate - Google Patents
A kind of continuous preparation method of high power polypropylene foamed plate Download PDFInfo
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- CN107972297A CN107972297A CN201711225984.3A CN201711225984A CN107972297A CN 107972297 A CN107972297 A CN 107972297A CN 201711225984 A CN201711225984 A CN 201711225984A CN 107972297 A CN107972297 A CN 107972297A
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- China
- Prior art keywords
- high power
- mould
- continuous preparation
- foamed plate
- polypropylene foamed
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29D—PRODUCING PARTICULAR ARTICLES FROM PLASTICS OR FROM SUBSTANCES IN A PLASTIC STATE
- B29D7/00—Producing flat articles, e.g. films or sheets
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/001—Combinations of extrusion moulding with other shaping operations
- B29C48/0011—Combinations of extrusion moulding with other shaping operations combined with compression moulding
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/001—Combinations of extrusion moulding with other shaping operations
- B29C48/0012—Combinations of extrusion moulding with other shaping operations combined with shaping by internal pressure generated in the material, e.g. foaming
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
- B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
- B29C48/001—Combinations of extrusion moulding with other shaping operations
- B29C48/0022—Combinations of extrusion moulding with other shaping operations combined with cutting
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J9/00—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof
- C08J9/04—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent
- C08J9/12—Working-up of macromolecular substances to porous or cellular articles or materials; After-treatment thereof using blowing gases generated by a previously added blowing agent by a physical blowing agent
- C08J9/122—Hydrogen, oxygen, CO2, nitrogen or noble gases
-
- C—CHEMISTRY; METALLURGY
- C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
- C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
- C08J2323/00—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers
- C08J2323/02—Characterised by the use of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Derivatives of such polymers not modified by chemical after treatment
- C08J2323/10—Homopolymers or copolymers of propene
- C08J2323/12—Polypropene
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
Abstract
The present invention provides a kind of continuous preparation method of high power polypropylene foamed plate, step includes：Pp material is expressed into the mould of preheating by plastic extruder plasticizing,At the same time special media is injected into mould to foam,Obtain plane foaming material base and exported from mould outlet,Pass through plain roller press polish and cooling,The plate obtained by size to preceding step is sheared,Get product,The head temperature of plastic extruder is 190 200 DEG C,Screw rod rotary speed is 300 1200rpm,The temperature of mould preheating is 180 190 DEG C,The pressure of foaming is 12 21MPa,The disk roller temperature of plain roller is 30 70 DEG C,The tractive force of disk roller is 1.0 5.0Mpa,Rotary speed is 300~1500rpm,Traction rotating speed is 300~1500rpm,The expansion ratio of plate is 5~40 times,The preparation method of high power polypropylene foamed plate provided by the present invention is continuous preparation method,The melting extrusion of raw material,The output dynamic of the peaceful fabric base of foaming carries out,Realize the production running of serialization,It is efficient,Technique is simple,It is adapted to industrialized popularization and application.
Description
Technical field
The invention belongs to technical field of macromolecules, and in particular to a kind of continuous preparation side of high power polypropylene foamed plate
Method.
Background technology
The application of various general-purpose plastics and engineering plastics on automobile is more and more extensive, they can not only mitigate parts
And complete vehicle weight, while the cost of raw material and vehicle price can also be reduced.In the numerous plastics family of application, polypropylene material
Material is even more to be widely used due to its light, inexpensive and excellent performance.Either outside automotive trim, automobile
Each systems such as decorations, enging cabin and chassis, are seen everywhere the application example of polypropylene material.With the development of science and technology, people
Also have more demands to automobile, energy-saving and environmental protection, comfortable, beautiful, low cost etc. all cause the application of polypropylene material to have
Broader prospect.
Polypropylene expanded plate is also referred to as PP foamed boards, be using polypropylene as raw material, what the technique such as foamed was prepared, density
Usually 0.19-0.024g/cm3, thickness 2-10mm, with product under excellent heat endurance, chemical stability and high temperature
Dimensional stability, excellent microwave adaptability and degradability, while also there is splendid machinability.Can be according to production
Moral character energy purposes adjusts correlated performance, can be widely used in auto parts and components and equipment manufacture industry.As automotive trim
Material, the performance that polypropylene board needs to have include：Scratch-resistant, resist white trace, heat-proof aging, distribution performance up to standard, fast light old
Change and anti-stickness, while also need to that there is good antistatic property.The foaming process of foamed plastics can be generally divided into two
Stage：It is that a large amount of uniform, fine and closely woven nuclei of bubbles are formed in plastic melt or liquid first, then reflation becomes required
Foam structure is fixed up by foam structure, final curing sizing, obtains foamed plastics.The common forming method of polypropylene has crowded
Go out, be molded and compression molding etc..
According to the source of blowing power in foaming, mechanical foaming, physical blowing, three kinds of chemical blowing generally can be divided into
Type.Mechanical foaming is by means of the strong stirring of machinery, when material is in liquid or paste, is stirred by aerating, makes sky
Gas enters in liquid or paste resin, these mixed air retain wherein during condensation of materials, Cheng Gu to be solidified
After state, become hole.Physical blowing is then by means of the change of foaming agent physical state in resin, forms a large amount of bubbles, than
As coal gas foams, using the foam process using coal gas as medium, since coal gas is there are inflammable and explosive hidden danger, in production
Than relatively hazardous, it in addition can also make the content of volatile organic compound of product exceeded.Physical blowing usually requires additionally addition hair
Infusion auxiliary foaming, for example irradiation foaming is, it is necessary to which first addition foaming agent is modified, after extruding pelletization, then with high temperature spoke
Capable foaming is shone into, addition foaming agent can also make the modified material content of volatile organic compound of granulation exceeded.Chemical blowing
Be by foaming agent occur chemical change caused by gas make it is resin expanded.It is polypropylene expanded to use chemical blowing mostly, make
Foaming agent has azodicarbonamide, diisopropyl azodiformate etc., and chemical blowing contains common problem encountered is that easily causing VOC
Measure exceeded, not environmentally, application is hardly resulted in auto parts field.
Chinese invention patent CN103497280A discloses a kind of crosslinked polypropylene microcellular foam material, is mixed by raw material
Close, CO2The technique productions such as gas impregnated base material, base material foaming, the detection of expanded material radiation treatment, high annealing, expanded material
Polypropylene microporous expanded material, the crosslinked polypropylene microcellular foam material which is prepared have that resilience is good, feel is thin
The characteristics of greasy, nonpoisonous and tasteless, but the method that is provided of the invention needs to mix by raw material, CO2Gas impregnated base material, base material
Multiple steps such as foaming, the detection of expanded material radiation treatment, high annealing, expanded material carry out successively, each step independent operating,
It is not carried out continuous production.Chinese invention patent CN104250326A provides a kind of system of polypropylene foamed plate or sheet material
Preparation Method, can obtain that surface is smooth from skinning, and cell diameter is uniform by the method for the invention, and poly- the third of closed pore hard structure
Alkene foaming plate or sheet material, but the method that is provided of the invention needs the reactor of two or more serial operations, carries out two
The propylene homo reaction in stage or more, it is necessary to equipment is more, cost is higher.
In conclusion still lack a kind of continuous method for preparing high power polypropylene foamed plate at present.
The content of the invention
A kind of continuous preparation method of high power polypropylene foamed plate, comprises the following steps：
(1) raw material is plasticized：Pp material is plasticized by plastic extruder and is extruded；
(2) material base foams：After mould is preheated, squeeze into the raw material of step (1), at the same inject into mould special media into
Row foaming, obtains plane foaming material base and is exported from mould outlet；
(3) press polish is shaped：Plane foaming material base obtained by step (2) is passed through into plain roller press polish and cooling；
(4) shear：The plate obtained by size to step (3) is sheared, and is got product；
The special media includes at least one of carbon dioxide, nitrogen, argon gas.
Preferably, the pp material described in step (1) is selected from least one of homopolypropylene, copolymer polypropylene.
Preferably, the carbon dioxide is supercritical carbon dioxide.
Preferably, the head temperature of the plastic extruder described in step (1) is 190-200 DEG C, and screw rod rotary speed is
300-1200rpm。
Preferably, the temperature of the mould preheating described in step (2) is 180-190 DEG C.
Preferably, the pressure of the foaming described in step (2) is 12-21MPa.
Preferably, the plain roller described in step (3) is double roller.
Preferably, the disk roller temperature of the plain roller described in step (3) is 30-70 DEG C, and the tractive force of disk roller is 1.0-
5.0Mpa, rotary speed are 300~1500rpm, and traction rotating speed is 300~1500rpm.
Preferably, the expansion ratio of the plate is 5~40 times.
The polypropylene foamed plate that a kind of continuous preparation method as described above is prepared.
In step (2), plastic extruder squeezes into the pp material of melting, while independent injection station equipment into mould
Special media is injected into mould, pp material is completed to foam and formed plane material base in a mold.Plane material base is being moulded
Material extruder is persistently extruded to be moved under the thrust of generation to mould outlet direction, is sent out eventually through mould outlet output plane
Foam material base.It is unclosed at mould outlet, by having foamed in mould but also not foamed material base to going out from the plane of mould output completely
Mouth plays sealing process, makes to maintain certain pressure in mould, finally realizes the continuous of polyethylene foam plate and prepares.Step
(3) plain roller in is double roller, on the one hand plays press polish, on the other hand plays cooling effect.
Preferably, the polypropylene foamed plate that the above method is prepared is applied to auto parts and components field, including instrument
Epidermis lining, middle handrail epidermis lining, tables and chairs lining, engine lower guard board, air conditioner ventilation after disk panel epidermis lining, door guard bar
Tube boot.
Supercritical fluid has the similar diffusivity of gas and the solvability of liquid, while has low-viscosity concurrently, low surface
The characteristic of tension force so that supercritical fluid can quickly penetrate into the material of micropore.
Temperature has a significant impact modified polypropene foaming process, solubility of the inertia foamed gas in modified polypropene
Foaming agents content is higher in system when being reduced with the rise of temperature, therefore controlling the foaming under relatively low melt temperature, melt
Intensity is lower, and foam structure is more unstable, easily causes abscess to merge, collapse and rupture；Melt temperature is high, the diffusion rate of gas
Faster, gas is easily dissipated from system, so as to reduce bubbling efficiency.Melt temperature is to modified polypropene extrusion and foaming process and sample
The foam structure of product has significant impact.Higher head temperature is kept to be conducive to obtain high foamability and excellent foam structure
Product, but after head temperature exceedes certain value, its influence to foam structure reduces.CO2Injection rate should maintain certain model
Enclosing interior could obtain preferable foam structure and high expansion ratio, CO2Injection rate is excessive, air pocket is likely to occur, when serious
There is hollow phenomenon.
Beneficial effects of the present invention
1st, the preparation method of high power polypropylene foamed plate provided by the present invention is continuous preparation method, and raw material melting is squeezed
Go out, the output dynamic progress for the peaceful fabric base that foams, realize the production running of serialization, efficient, technique is simple, is adapted to work
The popularization and application of industry；
2nd, any toxic reagent is not used in method provided by the invention in preparation process, and the plate being prepared meets ring
Guaranteed request, avoids the volatile organic compounds pollution that conventional method is be easy to cause；
3rd, the foaming plate density that method provided by the invention is prepared is low, and expansion ratio is adjustable, and uniform foam cell is fine and close,
Good mechanical performance.
Embodiment
Embodiment 1
A kind of continuous preparation method of high power polypropylene foamed plate, comprises the following steps：
(1) raw material is plasticized：Pp material is plasticized by plastic extruder and is extruded；
(2) material base foams：After mould is preheated, the raw material of step (1) is squeezed into, while CO is injected into mould2Sent out
Bubble, obtains plane foaming material base and is exported from mould outlet；
(3) press polish is shaped：Plane foaming material base obtained by step (2) is passed through into plain roller press polish and cooling；
(4) shear：The plate obtained by size to step (3) is sheared, and is got product；
The head temperature of step (1) plastic extruder is 190 DEG C, and screw rod rotary speed is 300rpm；Mould in step (2)
The temperature of preheating is 180 DEG C, and the pressure of foaming is 21MPa；The disk roller temperature of plain roller is 50 DEG C in step (3), and disk roller is led
Gravitation is 2.0Mpa, and rotary speed 600rpm, traction rotating speed is 600rpm.
Embodiment 2
The preparation method and embodiment 1 of the present embodiment are identical, wherein, the head temperature of step (1) plastic extruder is 190
DEG C, screw rod rotary speed is 300rpm；The temperature that mould preheats in step (2) is 180 DEG C, and the pressure of foaming is 12MPa；Step
(3) the disk roller temperature of plain roller is 50 DEG C in, and the tractive force of disk roller is 2.0Mpa, rotary speed 600rpm, and traction rotating speed is
600rpm。
Embodiment 3
The preparation method and embodiment 1 of the present embodiment are identical, and wherein the head temperature of step (1) plastic extruder is 190
DEG C, screw rod rotary speed is 300rpm；The temperature that mould preheats in step (2) is 180 DEG C, and the pressure of foaming is 17MPa；Step
(3) the disk roller temperature of plain roller is 50 DEG C in, and the tractive force of disk roller is 2.0Mpa, rotary speed 600rpm, and traction rotating speed is
600rpm。
Embodiment 4
The preparation method and embodiment 1 of the present embodiment are identical, and wherein the head temperature of step (1) plastic extruder is 190
DEG C, screw rod rotary speed is 300rpm；The temperature that mould preheats in step (2) is 180 DEG C, and the pressure of foaming is 17MPa；Step
(3) the disk roller temperature of plain roller is 70 DEG C in, and the tractive force of disk roller is 2.0Mpa, rotary speed 600rpm, and traction rotating speed is
600rpm。
Embodiment 5
The preparation method and embodiment 1 of the present embodiment are identical, and wherein the head temperature of step (1) plastic extruder is 190
DEG C, screw rod rotary speed is 300rpm；The temperature that mould preheats in step (2) is 180 DEG C, and the pressure of foaming is 17MPa；Step
(3) the disk roller temperature of plain roller is 30 DEG C in, and the tractive force of disk roller is 2.0Mpa, rotary speed 600rpm, and traction rotating speed is
600rpm。
The performance that plate is prepared in embodiment 1-5 is as shown in table 1：
The plate property of 1 embodiment 1-5 of table
Wherein, density measurement standard is ASTM D3574-2011, judgment criteria 87-106kg/m3For qualification；Tensile strength
Testing standard has for ASTM D412-2013, A pattern, gauge length 50mm, draw speed 500mm/min, and judgment criteria is drawing
Intensity >=1388KPa is stretched for qualification, and elongation at break >=61% is qualification；Tearing strength test standard is ASTM D624-
2012, c-type mould, tearing velocity 500mm/min, thickness 4.2mm, judgment criteria is that tearing strength >=9.7KN/m is conjunction
Lattice；Load deflection test standard is ASTM D3575D-2008, and decrement 25%, test speed 12.5mm/min, is judged
Standard is that load amount of deflection is that 164-240KPa is qualified.
Claims (9)
1. a kind of continuous preparation method of high power polypropylene foamed plate, it is characterised in that comprise the following steps：
(1) raw material is plasticized：Pp material is plasticized by plastic extruder and is extruded；
(2) material base foams：After mould is preheated, the raw material of step (1) is squeezed into, while injects special media into mould and is sent out
Bubble, obtains plane foaming material base and is exported from mould outlet；
(3) press polish is shaped：Plane foaming material base obtained by step (2) is passed through into plain roller press polish and cooling；
(4) shear：The plate obtained by size to step (3) is sheared, and is got product；
The special media includes at least one of carbon dioxide, nitrogen, argon gas.
A kind of 2. continuous preparation method of high power polypropylene foamed plate according to claim 1, it is characterised in that step
(1) pp material described in is selected from least one of homopolypropylene, copolymer polypropylene.
3. the continuous preparation method of a kind of high power polypropylene foamed plate according to claim 1, it is characterised in that described
Carbon dioxide be supercritical carbon dioxide.
A kind of 4. continuous preparation method of high power polypropylene foamed plate according to claim 1, it is characterised in that step
(1) head temperature of the plastic extruder described in is 190-200 DEG C, and screw rod rotary speed is 300-1200rpm.
A kind of 5. continuous preparation method of high power polypropylene foamed plate according to claim 1, it is characterised in that step
(2) temperature of the mould preheating described in is 180-190 DEG C.
A kind of 6. continuous preparation method of high power polypropylene foamed plate according to claim 1, it is characterised in that step
(2) blow pressure described in is 12-21MPa.
A kind of 7. continuous preparation method of high power polypropylene foamed plate according to claim 1, it is characterised in that step
(3) the disk roller temperature of the plain roller described in is 30-70 DEG C, and the tractive force of disk roller be 1.0-5.0Mpa, rotary speed is 300~
1500rpm, traction rotating speed are 300~1500rpm.
8. a kind of continuous preparation method of high power polypropylene foamed plate according to any one of claim 1-8, it is special
Sign is that the expansion ratio of the plate is 5~40 times.
A kind of 9. polypropylene foamed plate that preparation method continuous as claimed in any one of claims 1-9 wherein is prepared.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711225984.3A CN107972297A (en) | 2017-11-29 | 2017-11-29 | A kind of continuous preparation method of high power polypropylene foamed plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711225984.3A CN107972297A (en) | 2017-11-29 | 2017-11-29 | A kind of continuous preparation method of high power polypropylene foamed plate |
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| CN107972297A true CN107972297A (en) | 2018-05-01 |
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| CN201711225984.3A Pending CN107972297A (en) | 2017-11-29 | 2017-11-29 | A kind of continuous preparation method of high power polypropylene foamed plate |
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Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101560307A (en) * | 2009-05-19 | 2009-10-21 | 四川大学 | Method for preparing low density polypropylene foam section or beads by two-step extrusion molding |
| CN103963306A (en) * | 2013-08-06 | 2014-08-06 | 汕头市贝斯特科技有限公司 | Production system for supercritical gas PP physical foaming sheet |
-
2017
- 2017-11-29 CN CN201711225984.3A patent/CN107972297A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101560307A (en) * | 2009-05-19 | 2009-10-21 | 四川大学 | Method for preparing low density polypropylene foam section or beads by two-step extrusion molding |
| CN103963306A (en) * | 2013-08-06 | 2014-08-06 | 汕头市贝斯特科技有限公司 | Production system for supercritical gas PP physical foaming sheet |
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Application publication date: 20180501 |