CN117087192A - Preparation method of micro-foaming PP (Polypropylene) with oriented cells and ordered beta-type platelets - Google Patents
Preparation method of micro-foaming PP (Polypropylene) with oriented cells and ordered beta-type platelets Download PDFInfo
- Publication number
- CN117087192A CN117087192A CN202311220495.4A CN202311220495A CN117087192A CN 117087192 A CN117087192 A CN 117087192A CN 202311220495 A CN202311220495 A CN 202311220495A CN 117087192 A CN117087192 A CN 117087192A
- Authority
- CN
- China
- Prior art keywords
- foaming
- beta
- micro
- platelets
- ordered
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000005187 foaming Methods 0.000 title claims abstract description 55
- 238000002360 preparation method Methods 0.000 title claims abstract description 18
- 239000004743 Polypropylene Substances 0.000 title description 81
- 229920001155 polypropylene Polymers 0.000 title description 80
- -1 Polypropylene Polymers 0.000 title description 7
- 239000002667 nucleating agent Substances 0.000 claims abstract description 34
- 238000000034 method Methods 0.000 claims abstract description 31
- 239000008187 granular material Substances 0.000 claims abstract description 23
- 238000002156 mixing Methods 0.000 claims abstract description 16
- 150000001408 amides Chemical class 0.000 claims abstract description 15
- 230000008569 process Effects 0.000 claims abstract description 15
- 238000001125 extrusion Methods 0.000 claims abstract description 13
- 238000001746 injection moulding Methods 0.000 claims abstract description 5
- 238000010438 heat treatment Methods 0.000 claims description 21
- 238000001816 cooling Methods 0.000 claims description 19
- 239000006260 foam Substances 0.000 claims description 18
- 238000001764 infiltration Methods 0.000 claims description 14
- 230000008595 infiltration Effects 0.000 claims description 12
- CNFTYYKCUPPMIJ-UHFFFAOYSA-N 2,3-dicyclohexylbenzene-1,4-dicarboxamide Chemical group C1CCCCC1C=1C(C(=O)N)=CC=C(C(N)=O)C=1C1CCCCC1 CNFTYYKCUPPMIJ-UHFFFAOYSA-N 0.000 claims description 8
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 8
- 239000000203 mixture Substances 0.000 claims description 6
- 238000004519 manufacturing process Methods 0.000 claims description 3
- 239000008188 pellet Substances 0.000 claims description 3
- 239000000945 filler Substances 0.000 claims description 2
- 239000012774 insulation material Substances 0.000 claims description 2
- 239000000155 melt Substances 0.000 claims description 2
- 239000013078 crystal Substances 0.000 abstract description 16
- 239000000463 material Substances 0.000 abstract description 16
- 238000012545 processing Methods 0.000 abstract description 10
- 238000001035 drying Methods 0.000 abstract description 6
- 239000007790 solid phase Substances 0.000 abstract description 5
- 238000013461 design Methods 0.000 abstract description 3
- 230000002776 aggregation Effects 0.000 abstract description 2
- 238000004220 aggregation Methods 0.000 abstract description 2
- 230000033228 biological regulation Effects 0.000 abstract description 2
- 230000006911 nucleation Effects 0.000 abstract description 2
- 238000010899 nucleation Methods 0.000 abstract description 2
- 238000005469 granulation Methods 0.000 abstract 1
- 230000003179 granulation Effects 0.000 abstract 1
- 230000001360 synchronised effect Effects 0.000 abstract 1
- 230000000052 comparative effect Effects 0.000 description 28
- 238000007796 conventional method Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 238000010146 3D printing Methods 0.000 description 5
- 238000002425 crystallisation Methods 0.000 description 5
- 230000008025 crystallization Effects 0.000 description 5
- 239000011148 porous material Substances 0.000 description 5
- LNKJESSHRFPVPE-UHFFFAOYSA-N 5-(diethylamino)pentyl 3,4,5-trimethoxybenzoate;hydrochloride Chemical compound Cl.CCN(CC)CCCCCOC(=O)C1=CC(OC)=C(OC)C(OC)=C1 LNKJESSHRFPVPE-UHFFFAOYSA-N 0.000 description 4
- 238000006243 chemical reaction Methods 0.000 description 4
- 230000001276 controlling effect Effects 0.000 description 4
- 238000007599 discharging Methods 0.000 description 4
- 238000011049 filling Methods 0.000 description 4
- 238000001000 micrograph Methods 0.000 description 4
- 239000004033 plastic Substances 0.000 description 4
- 229920003023 plastic Polymers 0.000 description 4
- 230000009467 reduction Effects 0.000 description 4
- 238000001878 scanning electron micrograph Methods 0.000 description 4
- 238000001464 small-angle X-ray scattering data Methods 0.000 description 4
- 238000002791 soaking Methods 0.000 description 4
- 238000004736 wide-angle X-ray diffraction Methods 0.000 description 4
- 238000011161 development Methods 0.000 description 3
- 238000002844 melting Methods 0.000 description 3
- 230000008018 melting Effects 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- 238000012360 testing method Methods 0.000 description 3
- 238000004134 energy conservation Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- GHLZUHZBBNDWHW-UHFFFAOYSA-N nonanamide Chemical compound CCCCCCCCC(N)=O GHLZUHZBBNDWHW-UHFFFAOYSA-N 0.000 description 2
- 238000001338 self-assembly Methods 0.000 description 2
- 239000007787 solid Substances 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 230000002195 synergetic effect Effects 0.000 description 2
- 239000004698 Polyethylene Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 230000010261 cell growth Effects 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000003822 epoxy resin Substances 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 239000005457 ice water Substances 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000001939 inductive effect Effects 0.000 description 1
- 230000003993 interaction Effects 0.000 description 1
- 229920002521 macromolecule Polymers 0.000 description 1
- 239000007769 metal material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002159 nanocrystal Substances 0.000 description 1
- 231100000956 nontoxicity Toxicity 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 229920000647 polyepoxide Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920000915 polyvinyl chloride Polymers 0.000 description 1
- 239000004800 polyvinyl chloride Substances 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 238000003672 processing method Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
- 230000003313 weakening effect Effects 0.000 description 1
- 239000013585 weight reducing agent Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Classifications
-
- 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
- B29C69/00—Combinations of shaping techniques not provided for in a single one of main groups B29C39/00 - B29C67/00, e.g. associations of moulding and joining techniques; Apparatus therefore
- B29C69/02—Combinations of shaping techniques not provided for in a single one of main groups B29C39/00 - B29C67/00, e.g. associations of moulding and joining techniques; Apparatus therefore of moulding techniques only
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B9/00—Making granules
- B29B9/02—Making granules by dividing preformed material
- B29B9/06—Making granules by dividing preformed material in the form of filamentary material, e.g. combined with extrusion
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
- B29B9/00—Making granules
- B29B9/12—Making granules characterised by structure or composition
-
- 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
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/16—Cooling
-
- 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
- B29C35/00—Heating, cooling or curing, e.g. crosslinking or vulcanising; Apparatus therefor
- B29C35/16—Cooling
- B29C2035/1616—Cooling using liquids
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2023/00—Use of polyalkenes or derivatives thereof as moulding material
- B29K2023/10—Polymers of propylene
- B29K2023/12—PP, i.e. polypropylene
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
- B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
- B29K2105/0079—Liquid crystals
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Oral & Maxillofacial Surgery (AREA)
- Thermal Sciences (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
Abstract
The invention discloses a preparation method of micro-foaming PP with oriented cells and ordered beta-type platelets, and belongs to the technical field of new materials. The method comprises the following steps: drying and uniformly mixing PP granules and an amide beta nucleating agent, carrying out melt blending in an extruder, carrying out extrusion granulation, and then extruding or injection molding master batches to obtain a profile containing beta-type oriented crystals; subjecting the profile to solid phase hot stretching to further crush, rearrange and orient the crystals, and coolingPost-supercritical CO 2 Foaming to obtain the micro-foaming PP with oriented cells and ordered beta-type platelets. The invention utilizes the nucleating agent, the processing process and the force field to control the generation of the PP beta-type crystal structure and the regulation and control of the platelet stacking form, and then utilizes the high strength, high modulus and difficult foamability of the platelets to control the nucleation and growth of the limited space between crystals of the cells, thereby realizing the synchronous design of the final cell structure and the crystal aggregation form, reducing the apparent density of the PP and improving the mechanical property of the PP.
Description
Technical Field
The invention belongs to the technical field of new materials, and particularly relates to a preparation method of micro-foaming PP (Polypropylene) with oriented cells and ordered beta-type platelets.
Background
Energy conservation and emission reduction are important to realizing green development, and the weight reduction of vehicles such as automobiles, unmanned aerial vehicles and the like closely related to the energy conservation and emission reduction is urgent to replace the traditional metal materials with recyclable high-performance light plastic. The polypropylene (PP) has the characteristics of high temperature resistance, corrosion resistance, no toxicity, no smell, multiple processing and the like, has high yield, exceeds the first five general plastics of polyethylene and polyvinyl chloride, and is widely used for manufacturing important industrial products such as automobile inner and outer parts, unmanned aerial vehicle bodies and the like. Therefore, the realization of the light weight and high strength of PP is of great significance.
An important way to realize the preparation of the light high-strength PP material is to construct a crystal structure with orientation holes and high crystal orientation. The structure of the pore canal can reduce the apparent density of the PP material, the high crystallization can ensure the excellent mechanical property and heat resistance of the PP material, and the orientation of the pore canal and the wafer is the key for realizing the high load weight ratio.
The existing method for preparing the oriented pore canal structure mainly comprises two methods of 3D printing and ice template method. 3D printing is the most convenient and efficient method of achieving oriented wells, brett [ COMPTON B G, LEWIS J A. Advanced Materials,2014,26 (34): 5930-5.]The honeycomb-shaped epoxy resin composite material foam prepared by 3D printing and the like has the density0.38g/cm 3 Has a compressive strength of 20 MPa. In addition, the ice templating method is an effective method for preparing oriented channel materials [ SAMITSU S, PRUKSAWAN S, YOKOYAMAH, et al macromolecules,2022,55 (9): 3734-46 ].]，Wang[WANG B,TORRES-RENDON J G,YU J,et al.ACS Applied Materials&Interfaces,2015,7(8):4595-607.]The et al orient the cellulose nanocrystals using an ice template method so that the final prepared porous oriented film has a tensile strength of 187MPa, twice that of unoriented films.
Although 3D printing and ice templating have certain advantages in preparing porous oriented materials, 3D printing is low in efficiency and limited in accuracy, and materials with very small pores cannot be obtained, while ice templating is hardly suitable for preparing porous PP.
Therefore, the development of new methods to achieve high load to weight ratio PP, which is an important requirement for developing lightweight equipment, will also advantageously promote the development of the recyclable plastic industry.
Disclosure of Invention
In order to solve the problems in the prior art, the invention provides a preparation method of micro-foaming PP with oriented cells and ordered beta-type platelets. Aiming at the difficulty that the prior PP foam is difficult to realize light and high-strength synergy, the invention provides a novel preparation technology of a micro-foaming PP material with high load weight ratio, which is used for preparing the PP foam with a large number of micro-oriented holes and a high-oriented beta-type crystal structure, and improving the mechanical property while reducing the apparent density of the PP.
In order to achieve the above purpose, the present invention provides the following technical solutions:
the invention provides a preparation method of micro-foaming PP with a large number of oriented cells and ordered beta-type platelets, which comprises the following steps:
(1) Drying PP granules and an amide beta nucleating agent for 2 hours at 90 ℃, and uniformly mixing; melt blending the obtained mixture, extruding and granulating to obtain mixed granules;
(2) Extruding or injection molding the mixed granules obtained in the step (1) to obtain a section bar;
(3) Carrying out hot stretching on the section bar obtained in the step (2), and cooling after the stretching is finished;
(4) And (3) stretching and cooling the section bar in the step (3) in CO 2 And heating, pressure maintaining infiltration, pressure releasing foaming under the atmosphere, and cooling again to obtain the micro-foaming PP with oriented cells and ordered beta-type platelets.
In a preferred embodiment of the present invention, in the step (1), the amide β nucleating agent is a nucleating agent containing dicyclohexyl terephthalamide as a main component.
In the step (1), the mass of the amide beta nucleating agent is 0.05-2% of the mass of the PP granules, and the maximum heating temperature of the melt blending is 180-200 ℃.
As a preferable scheme of the invention, in the step (2), the highest heating temperature of the extrusion is 210-235 ℃, and the die temperature is 180-200 ℃.
As a preferable mode of the present invention, in the step (3), the heat stretching temperature is 70 to 110℃and the stretching ratio is 10 to 80% (i.e., further elongated by 10 to 80% based on the original length), and the cooling is performed in warm water.
In the step (4), the pressure maintaining infiltration temperature is 80-120 ℃, the pressure is 20-25 MPa, and the time is 2-12 h.
In the step (4), the pressure is released from the infiltration pressure to the normal pressure in the pressure release foaming process, the pressure release completion time is 15-60 s, and the re-cooling is carried out along with the cooling of the foaming kettle.
The invention also provides a PP foam prepared by the preparation method of the micro-foaming PP with the oriented cells and ordered beta-type platelets.
The invention also provides application of the PP foam in preparing automobile inner and outer parts, unmanned aerial vehicle bodies, water sports equipment, wind power generation blade fillers, heat insulation materials and building templates.
Compared with the prior art, the invention has the following beneficial effects:
the invention uses the high strength, high modulus and difficult foamability of the platelet in the PP, regulates and controls the beta-type platelet stacking form through the coupling of the crystallization template and the external field, skillfully uses the narrow amorphous area between adjacent platelets as a limited foaming space, controls the nucleation and growth of cells, and realizes the design of the final cell structure and aggregation form, thereby establishing a simple and efficient PP directional processing method with high load weight ratio.
By CO with supercritical 2 (ScCO 2 ) The interaction is stronger, and the self-assembly of the amide beta nucleating agent in the PP melt into the long strip-shaped crystallization templates with different length-diameter ratios and surface physical states can be controlled by means of self-assembly of the amide beta nucleating agent through self-intermolecular hydrogen bonds, so that the mechanical properties of the PP are improved while the apparent density of the PP is reduced through foaming.
The invention is deeply understood in the ScCO 2 The basic principle of foaming and the enhancement effect of ordered structure are started, the ordered pore morphology structure of wood is simulated, the gas-solid two phases are changed into enhancement phases by utilizing the synergistic enhancement effect when the gas-solid two phases are subjected to external load through the dominant crystal construction and the inter-crystal limited space design, and the micro-foaming PP with high load weight ratio is prepared, so that a new path and a new method are provided for preparing high-performance, lightweight and recyclable plastic products.
The micro-foaming PP with a large number of micro-oriented cells and ordered beta-type platelets is prepared by blending and extruding beta-nucleating agent and PP, controllably stretching and deforming, and then passing through ScCO 2 Obtained by foaming, involving extrusion, stretching, scCO 2 The operations such as foaming are simple, convenient and environment-friendly, and industrialization is easy to realize.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings that are needed in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.
In FIG. 1, a to c are external views of the samples of the micro-foaming PP prepared in comparative example 3, comparative example 1 and example 3, respectively.
In fig. 2, a1 and e1, a2 and e2, a3 and e3, and a4 and e4 are respectively the polarized light micrograph, the scanning electron micrograph, the two-dimensional wide-angle and small-angle X-ray scattering data of the PP profile to be foamed prepared in step (4) of comparative example 1 and comparative example 2, and b1 to d1, b2 to d2, b3 to d3, and b4 to b4 are respectively the polarized light micrograph, the scanning electron micrograph, the two-dimensional wide-angle and small-angle X-ray scattering data of the PP profile to be foamed prepared in step (4) of example 1 to 3.
Detailed Description
Various exemplary embodiments of the invention will now be described in detail, which should not be considered as limiting the invention, but rather as more detailed descriptions of certain aspects, features and embodiments of the invention. It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.
In addition, for numerical ranges in this disclosure, it is understood that each intermediate value between the upper and lower limits of the ranges is also specifically disclosed. Every smaller range between any stated value or stated range, and any other stated value or intermediate value within the stated range, is also encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range.
Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference for the purpose of disclosing and describing the methods and/or materials associated with the documents. In case of conflict with any incorporated document, the present specification will control.
It will be apparent to those skilled in the art that various modifications and variations can be made in the specific embodiments of the invention described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from consideration of the specification of the present invention. The specification and examples of the present invention are exemplary only.
As used herein, the terms "comprising," "including," "having," "containing," and the like are intended to be inclusive and mean an inclusion, but not limited to.
In the following examples, the PP pellets used were isotactic polypropylene; the normal temperature water is water with the temperature of 20-35 ℃; the raw materials used in the following examples and comparative examples are all commercially available. The description will not be repeated below.
Example 1
The preparation of the micro-foaming PP with oriented cells and ordered beta-type platelets comprises the following steps:
(1) Drying PP granules and dicyclohexyl terephthalamide (TMB-5) serving as an amide beta nucleating agent, wherein the content of the dicyclohexyl terephthalamide is 0.1wt% of the dosage of the PP granules in a baking oven at 90 ℃ for 2 hours, and uniformly mixing in a high-speed mixer;
(2) Setting the highest heating temperature to 200 ℃, setting other temperatures according to the conventional method, melting and blending the PP and the nucleating agent blend in a double-screw extruder, extruding and granulating to obtain the mixed granules.
(3) Extruding the mixed granules obtained in the step (2) in a single screw extruder to obtain a sheet, controlling the highest heating temperature in the extrusion process to be 210 ℃, controlling the die temperature to be 200 ℃, and setting other temperatures according to the conventional method.
(4) And (3) carrying out hot stretching on the sheet obtained in the step (3) at 100 ℃, wherein the stretching multiplying power is 30%, and rapidly cooling in the warm water after the stretching is finished.
(5) Placing the section bar after stretching and cooling in the step (4) in a high-pressure reaction kettle, and filling CO 2 And (3) discharging air after pressure relief, circulating twice, heating to the soaking temperature of 80 ℃, maintaining the pressure of 22MPa, maintaining the pressure for 4 hours, opening a pressure relief valve after the pressure maintaining is finished, reducing the pressure to normal pressure within 40 seconds, and taking out the foam after the foam is naturally cooled along with the kettle, so as to obtain the micro-foaming PP with oriented cells and ordered beta-type platelets.
Example 2
The difference from example 1 is only that in step (3), the maximum heating temperature of the extrusion process was controlled at 220 ℃.
Example 3
The difference from example 1 is only that in step (3), the maximum heating temperature of the extrusion process was controlled at 235 ℃.
Example 4
The preparation of the micro-foaming PP with oriented cells and ordered beta-type platelets comprises the following steps:
(1) Drying PP granules and dicyclohexyl terephthalamide (TMB-5) serving as an amide beta nucleating agent with the content of 0.05wt% of the PP granules in a baking oven at 90 ℃ for 2 hours, and uniformly mixing in a high-speed mixer;
(2) Setting the highest heating temperature to 180 ℃, setting other temperatures according to the conventional method, melting and blending the PP and the nucleating agent blend in a double-screw extruder, extruding and granulating to obtain the mixed granules.
(3) And (3) carrying out injection molding on the mixed granules obtained in the step (2) to obtain a sheet, wherein the highest heating temperature in the injection molding process is controlled at 210 ℃, the temperature of a nozzle is controlled at 180 ℃, and other temperatures are set according to the conventional method.
(4) And (3) carrying out hot stretching on the sheet obtained in the step (3) at 70 ℃, wherein the stretching multiplying power is 10%, and rapidly cooling in the warm water after the stretching is finished.
(5) Placing the section bar after stretching and cooling in the step (4) in a high-pressure reaction kettle, and filling CO 2 And (3) discharging air after pressure relief, circulating twice, heating to the soaking temperature of 100 ℃, maintaining the pressure of 20MPa for 2 hours, opening a pressure relief valve after the pressure maintaining is finished, reducing the pressure to normal pressure within 60 seconds, and taking out the foam after the foam is naturally cooled along with the kettle to obtain the micro-foaming PP with oriented cells and ordered beta-type platelets.
Example 5
The preparation of the micro-foaming PP with oriented cells and ordered beta-type platelets comprises the following steps:
(1) Drying PP granules and dicyclohexyl terephthalamide (TMB-5) serving as an amide beta nucleating agent, the content of which is 2wt% of the dosage of the PP granules, in a baking oven at 90 ℃ for 2 hours, and uniformly mixing in a high-speed mixer;
(2) Setting the highest heating temperature to 190 ℃, setting other temperatures according to the conventional method, melting and blending the PP and the nucleating agent blend in a double-screw extruder, extruding and granulating to obtain the mixed granules.
(3) Extruding the mixed granules obtained in the step (2) in a single screw extruder to obtain a sheet, controlling the highest heating temperature in the extrusion process to be 210 ℃, controlling the die temperature to be 190 ℃, and setting other temperatures according to the conventional method.
(4) And (3) carrying out hot stretching on the sheet obtained in the step (3) at the temperature of 85 ℃, wherein the stretching multiplying power is 80%, and rapidly cooling in ice water after the stretching is finished.
(5) Placing the section bar after stretching and cooling in the step (4) in a high-pressure reaction kettle, and filling CO 2 And (3) discharging air after pressure relief, circulating twice, heating to the infiltration temperature of 120 ℃, maintaining the pressure of 25MPa for 12 hours, opening a pressure relief valve after the pressure maintaining is finished, reducing the pressure to normal pressure within 15 seconds, and taking out the foam after natural cooling along with the kettle to obtain the micro-foaming PP with oriented cells and ordered beta-type platelets.
FIG. 1 shows the passing of supercritical CO under different conditions 2 The foaming PP, a-c are the appearance diagrams of the micro-foaming PP samples prepared in comparative example 3, comparative example 1 and example 3 respectively, namely the samples of PP which are extruded and formed by solid phase foaming without adding beta nucleating agent; a solid-phase foaming PP sample which is added with a beta nucleating agent and extruded and formed, but is not regulated and controlled by platelet arrangement; and example 3 produced a micro-foamed PP sample having both a large number of oriented cells and ordered beta platelets.
It can be seen that PP containing no beta nucleating agent, i.e. substantially no beta platelets, can be hardly foamed, whereas PP containing beta platelets can be foamed and the expansion ratio after stretching orientation can be increased.
Comparative examples 1 to 2
The difference from example 1 is only that in step (3), the maximum heating temperature of the extrusion process was controlled at 200℃and 255℃respectively.
In fig. 2, a1 and e1, a2 and e2, a3 and e3, and a4 and e4 are respectively comparative example 1, and the polarized light micrograph, the scanning electron micrograph, the two-dimensional wide-angle and small-angle X-ray scattering data of the PP profile to be foamed prepared in step (4) of comparative example 2, and b1 to d1, b2 to d2, b3 to d3, and b4 to b4 are respectively the polarized light micrograph, the scanning electron micrograph, the two-dimensional wide-angle and small-angle X-ray scattering data of the PP profile to be foamed prepared in step (4) of examples 1 to 3. As can be seen from fig. 2: in the process of extruding to obtain the profile, the regulation and control of the length-diameter ratio of the crystallization template, the PP platelet structure and the arrangement are realized through the change of the highest processing temperature. When the highest processing temperature is low (comparative example 1), the nucleating agent cannot self-assemble into an obvious fibrous structure, and the PP cannot be induced to form obvious ordered beta-type platelets, so that the ordered degree of the inter-crystalline foamable space arrangement is reduced; when the highest processing temperature is proper (examples 1-3), the nucleating agent can be self-assembled into fibrous structures with different length-diameter ratios, the PP can be induced to form a remarkably ordered beta-type platelet structure, and the platelet stacking mode is adjustable, so that a large number of inter-crystal limited foaming spaces which are orderly arranged can be formed in the PP, and the space orderly arrangement mode is adjustable; when the highest processing temperature is too high (comparative example 2), the nucleating agent can only self-assemble into dendritic morphology, and can only induce PP to form beta-type platelet structure without ordered arrangement, so that inter-crystalline foaming space with ordered arrangement cannot be constructed in PP.
Comparative example 3
The difference from example 1 is only that the amide type β nucleating agent of step (1) is added in an amount of 0.
Comparative example 4
The difference from example 1 is only that the infiltration temperature in step (5) is 70 ℃.
Comparative example 5
The difference from example 1 is only that the infiltration temperature in step (5) is 160 ℃.
Comparative example 6
The difference from example 1 is that the beta nucleating agent used in step (1) is a non-amide beta nucleating agent, specifically a polypropylene beta crystalline form nucleating agent WBG-ii available from guangdong new materials technologies inc.
Comparative example 7
The only difference from example 1 is that the dwell time in step (5) is 30 minutes.
Comparative example 8
The difference from example 1 is that the pressure release time in step (5) is 180 seconds.
Comparative example 9
(1) Drying PP granules and dicyclohexyl terephthalamide (TMB-5) serving as an amide beta nucleating agent, wherein the content of the dicyclohexyl terephthalamide is 0.1wt% of the dosage of the PP granules in a baking oven at 90 ℃ for 2 hours, and uniformly mixing in a high-speed mixer;
(2) The highest heating temperature was set to 200℃and other temperature settings were the same as in example 1, and the PP and nucleating agent blend was melt blended in a twin screw extruder and extrusion pelletized to give a mixed pellet.
(3) Extruding the mixed granules obtained in the step (2) in a single screw extruder to obtain a sheet, wherein the highest heating temperature in the extrusion process is controlled at 210 ℃, the die temperature is controlled at 200 ℃, and other temperature settings are the same as those in example 1.
(4) Placing the sheet obtained in the step (3) in a high-pressure reaction kettle, and filling CO 2 And (3) discharging air after pressure relief, circulating twice, heating to the soaking temperature of 80 ℃, maintaining the pressure at 22MPa for 4 hours, opening a pressure relief valve after the pressure maintaining is finished, reducing the pressure to normal pressure within 40 seconds, and taking out the foam after the foam is naturally cooled along with the kettle to obtain the micro-foaming PP.
Performance detection
The apparent density, tensile modulus in extrusion direction, tensile strength and elongation at break of the PP foams prepared in examples 1 to 5 and comparative examples 1 to 9 are shown below according to the test criteria and the results obtained.
TABLE 1 Performance test results of PP foam prepared in examples 1 to 5 and comparative examples 1 to 9
The apparent density was calculated by dividing the mass by the volume and the tensile properties were measured on a mechanical universal tester with the test standard ASTM D882.
As can be seen from table 1: the addition of amides to PP can self-assemble beta nucleating agents while ensuring proper processing temperature, proper hot stretching, and proper ScCO 2 The solid-phase foaming infiltration temperature, infiltration pressure, pressure relief and cooling rate can ensure that the apparent density of the obtained PP foam is obviously reduced and the mechanical property is obviously improved. While too high and too low extrusion temperatures (comparative examples 1-2) result in failure to build oriented ordered beta-type platelet structures in PP, decreasing the consistency and synergy of oriented cell and platelet arrangement, resulting in a significant decrease in mechanical properties. The short soaking time (comparative example 7) can lead to low foaming ratio, weakening of secondary crystallization behavior caused by molecular chain movement and insignificant improvement of mechanical properties. The increase in pressure release time (comparative example 8) also resulted in CO 2 The overflow is slow, the generated cells are reduced, the foaming multiplying power is low, the synergistic enhancement effect of the oriented cells and oriented arrangement platelets is not strong, and the mechanical strength is not obviously improved. The addition of no nucleating agent (comparative example 3) during the preparation leads to a significant reduction of the beta-crystal content and little foaming of the PP; if the non-amide beta nucleating agent (comparative example 6) is added, the effect of inducing PP to form ordered beta-type platelets is weakened, the effect of forming micro-oriented cells on a large scale is not added, and the mechanical enhancement effect of the micro-foaming sample in the processing direction is not obvious; scCO reduction during processing with the same other steps and parameters 2 The infiltration temperature (comparative example 4) during foaming is reduced, the foaming multiplying power is reduced, the density is increased, the oriented cells are difficult to form and play a role, and the mechanical strength is not obviously improved; improving ScCO under the condition of other steps and parameters in the processing process 2 The infiltration temperature during foaming (comparative example 5) can cause the damage of the obtained oriented crystal structure and the inter-crystal limited space of the ordered arrangement which is especially controlled, and the transformation of part of beta crystal to alpha crystal, the foaming process is difficult to control, the foaming multiplying power is too large, and the mechanical strength is seriously deteriorated. In the preparation process, the ScCO is directly carried out without hot stretching 2 Solid-phase foaming also results in a material with higher apparent density and poorer mechanical properties.
In the foregoing, the protection scope of the present invention is not limited to the preferred embodiments, and any person skilled in the art, within the scope of the present invention, should be covered by the protection scope of the present invention by equally replacing or changing the technical scheme and the inventive concept thereof.
Claims (9)
1. A process for the preparation of a micro-expanded PP having both oriented cells and ordered beta platelets, characterized by the steps of:
(1) Mixing PP granules with an amide beta nucleating agent, melt-blending the obtained mixture, extruding and granulating to obtain mixed granules;
(2) Extruding or injection molding the mixed granules obtained in the step (1) to obtain a section bar;
(3) Carrying out hot stretching on the section bar obtained in the step (2), and cooling after the stretching is finished;
(4) And (3) stretching and cooling the section bar in the step (3) in CO 2 And heating, pressure maintaining infiltration, pressure releasing foaming and cooling again under the atmosphere to obtain the micro-foaming PP with oriented cells and ordered beta-type platelets.
2. The method for producing a micro-foaming PP having both oriented cells and ordered beta-platelets according to claim 1, wherein in the step (1), the amide-based beta-nucleating agent is a dicyclohexyl terephthalamide-based nucleating agent.
3. The method for preparing a micro-foaming PP having both oriented cells and ordered beta platelets according to claim 1, wherein the mass of the amide beta nucleating agent is 0.05-2% of the mass of the PP pellet, and the highest heating temperature of the melt blending is 180-200 ℃.
4. The process for the preparation of a micro-foaming PP having both oriented cells and ordered beta platelets according to claim 1, wherein in step (2) the maximum heating temperature of the extrusion is 210-235 ℃ and the die temperature is 180-200 ℃.
5. The method for producing a micro-foaming PP having both oriented cells and ordered beta-type platelets according to claim 1, wherein in the step (3), the hot stretching temperature is 70 to 110 ℃, the stretching ratio is 10 to 80%, and the cooling is performed in warm water.
6. The method for preparing a micro-foaming PP having both oriented cells and ordered beta-type platelets according to claim 1, wherein in the step (4), the dwell-infiltration temperature is 80-120 ℃, the pressure is 20-25 MPa, and the dwell-infiltration time is 2-12 h.
7. The method for preparing the micro-foaming PP with oriented cells and ordered beta-type platelets simultaneously according to claim 1, wherein in the step (4), the pressure release foaming process is that the pressure is released from the infiltration pressure to the normal pressure, the pressure release completion time is 15-60 s, and the re-cooling is that the foam kettle is cooled.
8. A PP foam prepared by a process for the preparation of a micro-expanded PP having both oriented cells and ordered beta platelets according to any of claims 1-7.
9. Use of the PP foam according to claim 8 for the preparation of automotive interiors, exteriors, unmanned aerial vehicle bodies, water sports equipment, wind turbine blade fillers, heat insulation materials and building templates.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311220495.4A CN117087192A (en) | 2023-09-20 | 2023-09-20 | Preparation method of micro-foaming PP (Polypropylene) with oriented cells and ordered beta-type platelets |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311220495.4A CN117087192A (en) | 2023-09-20 | 2023-09-20 | Preparation method of micro-foaming PP (Polypropylene) with oriented cells and ordered beta-type platelets |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117087192A true CN117087192A (en) | 2023-11-21 |
Family
ID=88775069
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311220495.4A Pending CN117087192A (en) | 2023-09-20 | 2023-09-20 | Preparation method of micro-foaming PP (Polypropylene) with oriented cells and ordered beta-type platelets |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117087192A (en) |
Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004051670A (en) * | 2002-07-16 | 2004-02-19 | Mitsui Chemicals Inc | Organic polymer composition, cross-linked foam composed of the same composition and method for producing the same |
| JP2007056253A (en) * | 2005-07-28 | 2007-03-08 | Toray Ind Inc | Porous polypropylene film for heat insulating panel and heat insulating panel for vehicle using the same |
| CN102295807A (en) * | 2011-09-05 | 2011-12-28 | 浙江俊尔新材料有限公司 | Extrusion expanded polypropylene beads and preparation method thereof |
| US20170240733A1 (en) * | 2014-09-11 | 2017-08-24 | Borealis Ag | Polypropylene compositions for capacitor film |
| CN108819279A (en) * | 2018-06-04 | 2018-11-16 | 四川大学 | A kind of high porosity microporous polypropylene membrane and preparation method thereof |
| KR20180127756A (en) * | 2017-05-22 | 2018-11-30 | 주식회사 동원테크 | Polypropylene composition for foam injection molding with high ductility and manufacturing method of the same |
| CN109836702A (en) * | 2019-03-05 | 2019-06-04 | 贵州省材料产业技术研究院 | A kind of polypropylene-base in-situ micro-fibril foamed material of beta nucleater selective distribution and preparation method thereof |
| CN111286117A (en) * | 2020-02-11 | 2020-06-16 | 中国科学院宁波材料技术与工程研究所 | Method for forming open-cell polymer foam material by micropore injection molding and product |
| CN114213697A (en) * | 2021-12-01 | 2022-03-22 | 四川大学 | High-strength polylactic acid microporous foam material and preparation method thereof |
| CN115073854A (en) * | 2022-08-23 | 2022-09-20 | 江苏中科聚合新材料产业技术研究院有限公司 | High-temperature-resistant flame-retardant polypropylene foam material and preparation method and application thereof |
| CN115873293A (en) * | 2021-09-26 | 2023-03-31 | 中国石油化工股份有限公司 | Composition for preparing flame-retardant foamed polypropylene material, flame-retardant foamed polypropylene material and preparation method thereof |
| CN116589788A (en) * | 2023-04-14 | 2023-08-15 | 华南理工大学 | Toughness improvement method for thermal expansion microsphere foaming polypropylene material, and preparation method and application thereof |
-
2023
- 2023-09-20 CN CN202311220495.4A patent/CN117087192A/en active Pending
Patent Citations (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004051670A (en) * | 2002-07-16 | 2004-02-19 | Mitsui Chemicals Inc | Organic polymer composition, cross-linked foam composed of the same composition and method for producing the same |
| JP2007056253A (en) * | 2005-07-28 | 2007-03-08 | Toray Ind Inc | Porous polypropylene film for heat insulating panel and heat insulating panel for vehicle using the same |
| CN102295807A (en) * | 2011-09-05 | 2011-12-28 | 浙江俊尔新材料有限公司 | Extrusion expanded polypropylene beads and preparation method thereof |
| US20170240733A1 (en) * | 2014-09-11 | 2017-08-24 | Borealis Ag | Polypropylene compositions for capacitor film |
| KR20180127756A (en) * | 2017-05-22 | 2018-11-30 | 주식회사 동원테크 | Polypropylene composition for foam injection molding with high ductility and manufacturing method of the same |
| CN108819279A (en) * | 2018-06-04 | 2018-11-16 | 四川大学 | A kind of high porosity microporous polypropylene membrane and preparation method thereof |
| CN109836702A (en) * | 2019-03-05 | 2019-06-04 | 贵州省材料产业技术研究院 | A kind of polypropylene-base in-situ micro-fibril foamed material of beta nucleater selective distribution and preparation method thereof |
| CN111286117A (en) * | 2020-02-11 | 2020-06-16 | 中国科学院宁波材料技术与工程研究所 | Method for forming open-cell polymer foam material by micropore injection molding and product |
| CN115873293A (en) * | 2021-09-26 | 2023-03-31 | 中国石油化工股份有限公司 | Composition for preparing flame-retardant foamed polypropylene material, flame-retardant foamed polypropylene material and preparation method thereof |
| CN114213697A (en) * | 2021-12-01 | 2022-03-22 | 四川大学 | High-strength polylactic acid microporous foam material and preparation method thereof |
| CN115073854A (en) * | 2022-08-23 | 2022-09-20 | 江苏中科聚合新材料产业技术研究院有限公司 | High-temperature-resistant flame-retardant polypropylene foam material and preparation method and application thereof |
| CN116589788A (en) * | 2023-04-14 | 2023-08-15 | 华南理工大学 | Toughness improvement method for thermal expansion microsphere foaming polypropylene material, and preparation method and application thereof |
Non-Patent Citations (3)
| Title |
|---|
| 王金良: "《中国电池工业20年》", 30 June 2009, 中国轻工业出版社, pages: 321 - 322 * |
| 胡斌 等: "β型杂化串晶对超临界二氧化碳固相发泡聚丙烯拉伸性能的影响", 包装世界, 31 January 2019 (2019-01-31) * |
| 陈逸新;曹贤武;: "β成核剂对聚丙烯发泡材料的结晶行为和发泡性能的影响", 塑料工业, no. 03, 20 March 2016 (2016-03-20), pages 1 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Altan | Thermoplastic foams: Processing, manufacturing, and characterization | |
| CN103102583B (en) | A kind of polypropylene microporous expanded material and preparation method thereof | |
| CN114907608B (en) | Expanded polypropylene beads, process for producing the same and molded article | |
| CN102464828A (en) | Polypropylene/clay nanocomposite microcellular foam material and preparation method thereof | |
| CN113308017B (en) | Expanded polypropylene bead with excellent mechanical strength and molded part thereof | |
| CN112831127A (en) | Expandable polypropylene particles, modified polypropylene expanded beads and preparation thereof | |
| CN105837932A (en) | Preparation method for crystal polypropylene resin composition | |
| CN112940468A (en) | Polylactic acid-based foaming particles and preparation method thereof | |
| CN109575557A (en) | PC/ABS mixture for 3 D-printing and preparation method thereof and method of direct printing | |
| CN110016213B (en) | Polylactic acid foaming material with micro-nano composite pores and preparation method thereof | |
| CN111978585A (en) | Preparation method and application of polymer foam material with trimodal cellular structure | |
| CN106117741A (en) | A kind of polyethylene composite foam material and preparation method thereof | |
| KR20140017537A (en) | High strength extruded thermoplastic polymer foam | |
| CN116589788A (en) | Toughness improvement method for thermal expansion microsphere foaming polypropylene material, and preparation method and application thereof | |
| KR101735887B1 (en) | Polylactic acid-based resin foam and method of producing the same | |
| CN108912380B (en) | Method for preparing high-rate polymer foam by using PMMA/PVDF blend under low-pressure condition | |
| CN108219278A (en) | Micro-foaming polypropylene composite material of plant fiber and preparation method thereof | |
| CN105024028A (en) | Preparation method of three-layer composite lithium battery membrane | |
| CN110982189A (en) | PVC structural foam and preparation method thereof | |
| CN109265825B (en) | Polypropylene or polypropylene compound foamed product and preparation method thereof | |
| CN117087192A (en) | Preparation method of micro-foaming PP (Polypropylene) with oriented cells and ordered beta-type platelets | |
| CN115073854B (en) | High-temperature-resistant flame-retardant polypropylene foam material and preparation method and application thereof | |
| CN109251388B (en) | High-temperature-resistant cross-linked polyolefin foam material and preparation method thereof | |
| CN110128693B (en) | Polyolefin foam material and preparation method thereof | |
| CN109852009A (en) | A kind of high thermoplasticity expanded polyester |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |