CN108409985A - A method of it is handled by pre- isothermal cold crystallization and improves expanded polylactic acid multiplying power - Google Patents
A method of it is handled by pre- isothermal cold crystallization and improves expanded polylactic acid multiplying power Download PDFInfo
- Publication number
- CN108409985A CN108409985A CN201810312851.8A CN201810312851A CN108409985A CN 108409985 A CN108409985 A CN 108409985A CN 201810312851 A CN201810312851 A CN 201810312851A CN 108409985 A CN108409985 A CN 108409985A
- Authority
- CN
- China
- Prior art keywords
- isothermal
- polylactic acid
- cold crystallization
- blank
- multiplying power
- 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.)
- Granted
Links
Classifications
-
- 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
- C08J3/00—Processes of treating or compounding macromolecular substances
-
- 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
- C08J2201/00—Foams characterised by the foaming process
- C08J2201/02—Foams characterised by the foaming process characterised by mechanical pre- or post-treatments
- C08J2201/03—Extrusion of the foamable blend
-
- 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
- C08J2203/00—Foams characterized by the expanding agent
- C08J2203/06—CO2, N2 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
- C08J2205/00—Foams characterised by their properties
- C08J2205/04—Foams characterised by their properties characterised by the foam pores
- C08J2205/044—Micropores, i.e. average diameter being between 0,1 micrometer and 0,1 millimeter
-
- 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
- C08J2367/00—Characterised by the use of polyesters obtained by reactions forming a carboxylic ester link in the main chain; Derivatives of such polymers
- C08J2367/04—Polyesters derived from hydroxy carboxylic acids, e.g. lactones
Landscapes
- Chemical & Material Sciences (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Manufacture Of Porous Articles, And Recovery And Treatment Of Waste Products (AREA)
- Biological Depolymerization Polymers (AREA)
Abstract
The method improving expanded polylactic acid multiplying power is handled by pre- isothermal cold crystallization the present invention relates to a kind of, is included the following steps：1) through melting extrusion or hot pressing, polylactic acid or its blend are made to the blank of amorphous or low crystallization；2) above-mentioned blank is carried out pre- isothermal cold crystallization to handle, obtains the pre- isothermal processes sample with certain crystallinity and crystal habit；3) above-mentioned pre- isothermal processes sample is subjected to high pressure gas swelling infiltration and expanded material is made by quick pressure releasing.The present invention can effectively solve the technical barrier that hypocrystalline polylactic acid melt intensity is low, expandability is poor, expansion ratio is low, regulate and control the foam structure of polylactic acid foam material, and it is simple for process, process is green, of low cost, and the application field of polylactic acid foam material can be further expanded.
Description
Technical field
The invention belongs to field of high polymer material processing, and in particular to a kind of handled by pre- isothermal cold crystallization improves poly- breast
The method of sour expansion ratio.
Background technology
High molecular foam material has lightweightn and material saving, specific strength height, damping, buffering, heat insulation and acoustic absorption, efficient absorption etc. excellent
Performance, thus there is extensive use in fields such as automobile, household electrical appliances, packaging, building, medicine, aerospaces.However, existing high score
It is matrix that sub- expanded material uses the petroleum-based plastics such as polystyrene, polypropylene, polyethylene more, and a large amount of of these materials use not
Can only consume petroleum resource, cause serious petroleum resources exhausted, also because it is difficult to easily cause the ecologies such as white pollution due to degradation
Environmental problem.Therefore, exploitation and popularization biology base and Biodegradable high molecular expanded material are extremely urgent.
In numerous biology bases and biodegradated polymer materal, polylactic acid (PLA) material technology is ripe, at low cost, comprehensive
It is good to close performance.However, polylactic acid is linear those semi-crystalline materials, crystallization is slow, melt strength is poor, foaming mechanism is complicated, expandability
Difference.It is difficult to prepare that expansion ratio is high, polylactic acid foam of uniform foam cell.And expansion ratio is the most intuitive body of foaming materials performance
It is existing.Meanwhile big multiplying power expanded material has great application potential in fields such as heat-insulated, absorption, bufferings.Therefore, big times is prepared
Rate polylactic acid foam material is the difficult point and hot issue in current foaming field.
Chinese patent CN102911392A, which is disclosed, utilizes supercritical fluid CO2Prepare radiation modification polylactic acid foam material
Method, which is first made sheet material by polylactic acid and sensitizer melt blending, then the above sheet is carried out60Co- gamma-rays spokes
It penetrates, the sheet material after radiation is finally subjected to supercritical CO2Foaming.The operation principle of the invention is to improve molecule by ray radiation
The crosslinking degree of chain, and then improve the melt strength of polylactic acid, the final foam performance for improving polylactic acid.But the invention is used
Ray radiation cost it is higher, and with certain dangerous and pollution, operating environment requirements are harsh.
Chinese patent CN106751611A discloses that a kind of high fondant-strength expanded polylactic acid is resin dedicated and its preparation side
Method, raw material include polylactic acid, biodegradable copolymer, chain extender, melt reinforcing agent, nucleating agent and lubricant.The patent
Core concept be by chain extension improve polylactic acid melt strength, and then improve polylactic acid foam performance.But this method relates to
And a variety of chemical assistants, it is not only of high cost, but also chemical contamination is easily caused, endanger operating personnel's health.
Di Y. et al. report it is a kind of modified method being branched to commercial polylactic acid using chain extender, change after branched
The melt viscoelasticity of polylactic acid has been apt to it, final expansion ratio can increase to 19 times by 10 times.But this method need to use a variety of chain extensions
Agent, of high cost and pollution are big.[Di Y.,et al.Reactively Modified Poly(lactic acid):
Properties and Foam Processing[J].Macromolecular Materials&Engineering,2010,
290(11):1083-1090.]
In conclusion to improve the expandability of polylactic acid, existing method mostly uses the means such as chain extender and ray radiation, right
Linear polylactic acid carries out chain extension, branched, crosslinking isodesmic structure level modification.However, existing method it is complicated for operation, it is of high cost,
Pollution is big.Meanwhile the condensed state structures such as crystallization equally influence expanded polylactic acid significantly, and existing method has ignored and is gone through by heat
The method of history design regulates and controls condensed state structure.By consulting existing literature data, do not find through pre- isothermal cold junction yet
Crystalline substance processing is reported come the method for improving expanded polylactic acid multiplying power.
Invention content
For the above-mentioned prior art the problem of, it is an object of the present invention to provide one kind passing through pre- isothermal cold junction
The method that crystalline substance processing improves expanded polylactic acid multiplying power.Problem slow in view of polylactic acid crystal, melt strength is poor, the present invention pass through pre-
The processing of isothermal cold crystallization increases crystalline temperature and crystallinity in matrix, ensures to retain in follow-up saturation process more orderly
Structure, and physics entanglement network is formed, improve melt viscoelasticity, and then improve expanded polylactic acid multiplying power.
In order to solve the above technical problems, the technical scheme is that：
A method of it is handled by pre- isothermal cold crystallization and improves expanded polylactic acid multiplying power：The specific steps are：
1) through melting extrusion or hot pressing, polylactic acid or its blend are made to the blank of amorphous or low crystallization；
2) under certain pre- isothermal cold crystallization treatment temperature and pre- isothermal cold crystallization processing time, above-mentioned blank is carried out pre-
The processing of isothermal cold crystallization, obtains the pre- isothermal processes sample with certain crystallinity and crystal habit；
3) under certain saturation pressure, saturation temperature and saturation time, above-mentioned pre- isothermal processes sample is subjected to high pressure gas
Expanded material is made by quick pressure releasing in body swelling infiltration.
Preferably, the polylactic acid or its blend include pure polylactic acid, polylactic acid and organic admixture, polylactic acid and
Inorganic filler compound.
Preferably, the detailed process of step 2) is：
1. blank obtained by step 1) is placed in the heating container of room temperature at room temperature, it is then that blank heating is cold to pre- isothermal
Crystallization treatment temperature, and kept for certain pre- isothermal cold crystallization processing time, continue thereafter with the saturation temperature for being heated to material；
2. blank obtained by step 1) is placed in the heating container of room temperature at room temperature, then by blank heating to pre- etc.
Warm cold crystallization treatment temperature, and kept for certain pre- isothermal cold crystallization processing time, then blank is taken out from heating container,
It is placed in air or is cooled down in liquid；
3. heating container is first heated to pre- isothermal treatment temperatures, then the blank of step 1) at room temperature is placed in heating
It in container, and is kept for certain pre- isothermal cold crystallization processing time, blank is taken out from heating container then, is placed in air
Or it is cooling in liquid；
4. heating container is first heated to pre- isothermal treatment temperatures, then the blank of step 1) at room temperature is placed in heating
In container, and kept for certain pre- isothermal cold crystallization processing time, then by blank heating to saturation temperature.
Preferably, in step 2), the pre- isothermal cold crystallization processing is the pre- isothermal processes of single-stage or multistage pre- isothermal processes,
Wherein, the pre- isothermal processes of single-stage carry out pre- isothermal processes using single pre- isothermal temperature, and multistage pre- isothermal processes are then to use
Multiple pre- isothermal temperatures carry out pre- isothermal processes step by step.
Preferably, in step 2), the pre- isothermal cold crystallization treatment temperature is the glass transition temperature between polylactic acid
TgWith fusing point TmBetween, i.e., 60~170 DEG C.
It is further preferred that the pre- isothermal cold crystallization temperature ranges are 70~140 DEG C.
Preferably, in step 2), the pre- isothermal cold crystallization processing time is 5~120min, it is further preferred that processing
Time is 10~60min.
Preferably, the detailed process of step 3) is：
1. and 4. except above-mentioned in addition to situation in step 2), for 2. and 3. two kinds of situations in step 2), first autoclave is heated
To the saturation temperature of polylactic acid, then by step, 2. or 3. the pre- isothermal processes sample of gained is placed in autoclave, closes autoclave；So
Afterwards, for 1., 2., 3. and 4. four kinds of situations in step 2), then with low-pressure gas autoclave is purged, is filled with gas to saturation pressure
Power, after keeping certain saturation time, quick pressure releasing, and autoclave is placed in ice water and is quickly cooled down sizing.
Preferably, saturation pressure described in step 3) is 1500~4500psi；The saturation temperature is 90~160 DEG C；Institute
It is 50~130min to state saturation time.
Preferably, gas described in step 3) is carbon dioxide, nitrogen, pentane and its mixed gas.
Pre- isothermal cold crystallization process is act as：It being handled through pre- isothermal cold crystallization, the crystallinity and crystalline temperature of matrix increase,
More ordered structures can be retained in follow-up saturation process, and form physics entanglement network, improve the viscoplasticity of melt, into
And improve the expansion ratio of polylactic acid.
Beneficial effects of the present invention
Compared with directly heating the conventional method to saturation temperature by non-isothermal mode, the present invention can significantly improve poly- breast
The foam performance of acid, improves the expansion ratio of polylactic acid, widens the foaming window of polylactic acid；With by chain extension, it is branched, crosslinking,
The method that the modes such as blending prepare big multiplying power polylactic acid foam is compared, and the present invention uses non-modified conventional commercial linear poly- breast
Acid does not destroy the biological degradability and recyclability of polylactic acid, and entire technical process is not related to any organic solvent and chemistry
Chain extender, ray radiation and blending filler etc. is added without additional in auxiliary agent.Therefore, polylactic acid can not only be significantly improved
Expansion ratio, and technical process is simple, of low cost, environmentally protective.
Description of the drawings
The accompanying drawings which form a part of this application are used for providing further understanding of the present application, and the application's shows
Meaning property embodiment and its explanation do not constitute the improper restriction to the application for explaining the application.
Fig. 1 is the temperature curve of conventional method and the method for the present invention；
Fig. 2 is the sample section stereoscan photograph of embodiment 1；
Fig. 3 is the sample section stereoscan photograph of embodiment 2；
Fig. 4 is the sample section stereoscan photograph of embodiment 3；
Fig. 5 is the sample section stereoscan photograph of embodiment 4；
Fig. 6 is the sample section stereoscan photograph of reference examples 1；
Fig. 7 is the sample section stereoscan photograph of reference examples 2.
Specific implementation mode
It is noted that following detailed description is all illustrative, it is intended to provide further instruction to the application.Unless another
It indicates, all technical and scientific terms used herein has usual with the application person of an ordinary skill in the technical field
The identical meanings of understanding.
It should be noted that term used herein above is merely to describe specific implementation mode, and be not intended to restricted root
According to the illustrative embodiments of the application.As used herein, unless the context clearly indicates otherwise, otherwise singulative
It is also intended to include plural form, additionally, it should be understood that, when in the present specification using term "comprising" and/or " packet
Include " when, indicate existing characteristics, step, operation, device, component and/or combination thereof.
With reference to embodiment, the present invention is further described.
Analysis test method is as follows：According to GB/T 6343-2009, foamed sample density p is measuredfIt is close with unexpanded sample
Spend ρp, expansion ratio R=ρp/ρf.Foamed sample impregnates brittle failure in liquid nitrogen, and scanning electron microscopic observation is carried out after section metal spraying, and
Count its foam structure.
As shown in Figure 1, conventional method is the method without pre- isothermal cold crystallization processing step, wherein a is conventional method,
B is the method by pre- isothermal cold crystallization processing step of the application；As can be seen from the figure the present processes and routine side
During method, temperature change is different.
Embodiment 1：The preparation of the pure PLA expanded materials handled through pre- isothermal cold crystallization
Processing is dried in pure polylactic acid (4032D, Natureworks company) particle in vacuum drying chamber.It utilizes
Double screw extruder, by the particles of polylactic acid after drying carry out squeeze out and it is air-cooled, prepare the extrusion sample that diameter is about 3.5mm.
Autoclave is first heated to 80 DEG C, then the above-mentioned extrusion sample of certain length is placed in autoclave, isothermal 15 minutes, is carried out pre-
The processing of isothermal cold crystallization；Then sample is taken out, and is quickly placed into ice water cooling；Autoclave is continued to be heated to 137 DEG C, and
By treated, sample is placed in autoclave, utilizes low pressure CO2Autoclave is purged, and is sealed；It is 2500psi to be filled with saturation pressure
CO2, constant temperature and pressure 50 minutes；Quick pressure releasing, and autoclave is placed in ice water with cooling and shaping.The poly- breast obtained after foaming
The expansion ratio of sour expanded material is about 10.8 times, and abscess average-size is about 18.8 μm, and cell density is about 1.4 × 108A/
cm3.Its section abscess pattern is as shown in Figure 2.
Embodiment 2：The preparation of the pure PLA expanded materials handled through pre- isothermal cold crystallization
Processing is dried in pure polylactic acid (4032D, Natureworks company) particle in vacuum drying chamber.It utilizes
Double screw extruder, by the particles of polylactic acid after drying carry out squeeze out and it is air-cooled, prepare the extrusion sample that diameter is about 3.5mm.
The above-mentioned extrusion sample of certain length is placed in autoclave, low pressure CO is utilized2Autoclave is purged, and is sealed；By autoclave plus
Heat is to 90 DEG C, and isothermal 15 minutes, carries out pre- isothermal cold crystallization processing；It continues thereafter with and is heated to 137 DEG C, being filled with saturation pressure is
The CO of 2500psi2, constant temperature and pressure 50 minutes；Quick pressure releasing, and autoclave is placed in ice water with cooling and shaping.After foaming
To the expansion ratio of polylactic acid foam material be about 17.7 times, abscess average-size is about 18.0 μm, and cell density is about 2.2
×108A/cm3.Its section abscess pattern is as shown in Figure 3.Embodiment 2 and embodiment 1 difference lies in：Embodiment 2 is using above-mentioned
The mode of situation 1. is heated in step 2), and pre- isothermal temperature is 90 DEG C；And embodiment 1 use above-mentioned steps 2) in situation 3.
Mode heated, pre- isothermal temperature be 80 DEG C.
Embodiment 3：The preparation of the pure PLA expanded materials handled through pre- isothermal cold crystallization
Processing is dried in pure polylactic acid (4032D, Natureworks company) particle in vacuum drying chamber.It utilizes
Double screw extruder, by the particles of polylactic acid after drying carry out squeeze out and it is air-cooled, prepare the extrusion sample that diameter is about 3.5mm.
Autoclave is first heated to 100 DEG C, then the above-mentioned extrusion sample of certain length is placed in autoclave, isothermal 15 minutes, is carried out
Pre- isothermal cold crystallization processing；Then sample is taken out, and is quickly placed into ice water cooling；Autoclave is continued to be heated to 137 DEG C,
And by treated, sample is placed in autoclave, utilizes low pressure CO2Autoclave is purged, and is sealed；Being filled with saturation pressure is
The CO of 2500psi2, constant temperature and pressure 50 minutes；Quick pressure releasing, and autoclave is placed in ice water with cooling and shaping.After foaming
To the expansion ratio of polylactic acid foam material be about 8.7 times, abscess average-size is about 16.3 μm, and cell density is about 2.3
×108A/cm3.Its section abscess pattern is as shown in Figure 4.Difference lies in the height of embodiment 3 by embodiment 3 and embodiment 1 unique
It is 100 DEG C to press kettle preheating temperature.
Embodiment 4：The preparation of the pure PLA expanded materials handled through pre- isothermal cold crystallization
Processing is dried in pure polylactic acid (4032D, Natureworks company) particle in vacuum drying chamber.It utilizes
Double screw extruder, by the particles of polylactic acid after drying carry out squeeze out and it is air-cooled, prepare the extrusion sample that diameter is about 3.5mm.
Autoclave is first heated to 90 DEG C, then the above-mentioned extrusion sample of certain length is placed in autoclave, isothermal 60 minutes, is carried out pre-
The processing of isothermal cold crystallization；Then sample is taken out, and is quickly placed into ice water cooling；Autoclave is continued to be heated to 137 DEG C, and
By treated, sample is placed in autoclave, utilizes low pressure CO2Autoclave is purged, and is sealed；It is 2500psi to be filled with saturation pressure
CO2, constant temperature and pressure 50 minutes；Quick pressure releasing, and autoclave is placed in ice water with cooling and shaping.The poly- breast obtained after foaming
The expansion ratio of sour expanded material is about 9.0 times, and abscess average-size is about 15.8 μm, and cell density is about 2.8 × 108A/
cm3.Its section abscess pattern is as shown in Figure 5.Embodiment 4 is the difference from example 2 is that embodiment 4 uses above-mentioned steps 2) in
The mode of situation 3. is heated, and pre- isothermal time is 60 minutes；And embodiment 2 is using above-mentioned steps 2) in situation 1. by the way of
It is heated, pre- isothermal time is 15 minutes.
Reference examples 1：The preparation of pure PLA expanded materials without the processing of pre- isothermal cold crystallization
Processing is dried in pure polylactic acid (4032D, Natureworks company) particle in vacuum drying chamber.It utilizes
Double screw extruder, by the particles of polylactic acid after drying carry out squeeze out and it is air-cooled, prepare the extrusion sample that diameter is about 3.5mm.
The above-mentioned extrusion sample of certain length is placed in the autoclave of room temperature, low pressure CO is utilized2Autoclave is purged, and is sealed；It will be high
Pressure kettle is heated to 137 DEG C, is filled with the CO that saturation pressure is 2500psi2, constant temperature and pressure 50 minutes；Quick pressure releasing, and by autoclave
It is placed in ice water with cooling and shaping.The expansion ratio of the polylactic acid foam material obtained after foaming is about 3.2 times, and abscess is averaged ruler
Very little about 8.4 μm, cell density is about 1.6 × 109A/cm3.Its section abscess pattern is as shown in Figure 6.
Reference examples 2：The preparation of pure PLA expanded materials without the processing of pre- isothermal cold crystallization
Processing is dried in pure polylactic acid (4032D, Natureworks company) particle in vacuum drying chamber.It utilizes
Double screw extruder, by the particles of polylactic acid after drying carry out squeeze out and it is air-cooled, prepare the extrusion sample that diameter is about 3.5mm.
It is different in the autoclave of room temperature from sample is placed directly in reference examples 1, it is that autoclave is first heated to 137 DEG C in reference examples 2,
Then sample will be squeezed out again to be placed in autoclave, utilizes low pressure CO2Autoclave is purged, and is sealed；Being filled with saturation pressure is
The CO of 2500psi2, constant temperature and pressure 50 minutes；Quick pressure releasing, and autoclave is placed in ice water with cooling and shaping.After foaming
To the expansion ratio of polylactic acid foam material be about 2.6 times, abscess average-size is about 9.8 μm, cell density is about 1.0 ×
109A/cm3.Its section abscess pattern is as shown in Figure 7.
Found out by above-mentioned, the present invention is in 137 DEG C of saturation temperature and CO2Under conditions of saturation pressure is 2500psi, when poly- breast
When the pre- isothermal temperature of sour expanded material is 90 DEG C, pre- isothermal time is 15 minutes, expansion ratio is maximum, pre- without being arranged
The comparative example 1 of isothermal cold crystallization process and the expansion ratio of comparative example 2 are then very low.
The foregoing is merely the preferred embodiments of the application, are not intended to limit this application, for the skill of this field
For art personnel, the application can have various modifications and variations.Within the spirit and principles of this application, any made by repair
Change, equivalent replacement, improvement etc., should be included within the protection domain of the application.
Claims (10)
1. a kind of handling the method for improving expanded polylactic acid multiplying power by pre- isothermal cold crystallization, it is characterised in that：The specific steps are：
1) through melting extrusion or hot pressing, polylactic acid or its blend are made to the blank of amorphous or low crystallization；
2) under certain pre- isothermal cold crystallization treatment temperature and pre- isothermal cold crystallization processing time, above-mentioned blank is subjected to pre- isothermal
Cold crystallization processing, obtains the pre- isothermal processes sample with certain crystallinity and crystal habit；
3) under certain saturation pressure, saturation temperature and saturation time, it is molten that above-mentioned pre- isothermal processes sample is subjected to high pressure gas
Expanded material is made by quick pressure releasing in swollen infiltration.
2. a kind of method improving expanded polylactic acid multiplying power according to claim 1, it is characterised in that：The step 2)
Detailed process is：
1. blank obtained by step 1) to be placed in the heating container of room temperature at room temperature, then by blank heating to pre- isothermal cold crystallization
Treatment temperature, and kept for certain pre- isothermal cold crystallization processing time, continue thereafter with the saturation temperature for being heated to material；
2. blank obtained by step 1) is placed in the heating container of room temperature at room temperature, it is then that blank heating is cold to pre- isothermal
Crystallization treatment temperature, and kept for certain pre- isothermal cold crystallization processing time, blank is taken out from heating container then, is placed in
It is cooled down in air or in liquid；
3. heating container is first heated to pre- isothermal treatment temperatures, then the blank at room temperature that step 1) obtains is placed in plus
It in heat container, and is kept for certain pre- isothermal cold crystallization processing time, blank is taken out from heating container then, is placed in air
In or liquid in it is cooling；
4. heating container is first heated to pre- isothermal treatment temperatures, then the blank at room temperature that step 1) obtains is placed in plus
In heat container, and kept for certain pre- isothermal cold crystallization processing time, then by blank heating to saturation temperature.
3. a kind of method improving expanded polylactic acid multiplying power according to claim 2, it is characterised in that：Described in step 2)
Pre- isothermal cold crystallization processing is the pre- isothermal processes of single-stage or multistage pre- isothermal processes.
4. a kind of method improving expanded polylactic acid multiplying power according to claim 2, it is characterised in that：The pre- isothermal is cold
Crystallization treatment temperature is the glass transition temperature T between polylactic acidgWith fusing point TmBetween, i.e., 60~170 DEG C；
Preferably, the pre- isothermal cold crystallization temperature ranges are 70~140 DEG C.
5. a kind of method improving expanded polylactic acid multiplying power according to claim 2, it is characterised in that：The pre- isothermal is cold
The crystallization treatment time is 5~120min, preferably 10~60min.
6. a kind of method improving expanded polylactic acid multiplying power according to claim 2, it is characterised in that：Step 3) it is specific
Process is：
1. and 4. except in step 2) in addition to situation, for 2. and 3. two kinds of situations in step 2), autoclave is first heated to polylactic acid
Saturation temperature, then pre- isothermal processes sample obtained by step 2) is placed in autoclave, closes autoclave；Then, for step
2) 1., 2., 3. and 4. four kinds of situations in, then autoclave is purged with low-pressure gas, gas is filled with to saturation pressure, keeps certain
After saturation time, quick pressure releasing, and autoclave is placed in ice water and is quickly cooled down sizing.
7. a kind of method improving expanded polylactic acid multiplying power according to claim 6, it is characterised in that：In the step 3)
The saturation pressure is 1500~4500psi.
8. a kind of method improving expanded polylactic acid multiplying power according to claim 6, it is characterised in that：In the step 3)
The saturation temperature is 90~160 DEG C.
9. a kind of method improving expanded polylactic acid multiplying power according to claim 6, it is characterised in that：In the step 3)
The saturation time is 50~130min.
10. a kind of method improving expanded polylactic acid multiplying power according to claim 6, it is characterised in that：Institute in step 3)
It is carbon dioxide, nitrogen, pentane and its mixed gas to state gas.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810312851.8A CN108409985B (en) | 2018-04-09 | 2018-04-09 | Method for improving foaming ratio of polylactic acid through pre-isothermal cold crystallization treatment |
| PCT/CN2018/103673 WO2019196320A1 (en) | 2018-04-09 | 2018-08-31 | Method for improving foaming rate of polylactic acid through pre-isothermal cold crystallization treatment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810312851.8A CN108409985B (en) | 2018-04-09 | 2018-04-09 | Method for improving foaming ratio of polylactic acid through pre-isothermal cold crystallization treatment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108409985A true CN108409985A (en) | 2018-08-17 |
| CN108409985B CN108409985B (en) | 2020-12-29 |
Family
ID=63134962
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810312851.8A Active CN108409985B (en) | 2018-04-09 | 2018-04-09 | Method for improving foaming ratio of polylactic acid through pre-isothermal cold crystallization treatment |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN108409985B (en) |
| WO (1) | WO2019196320A1 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109354847A (en) * | 2018-10-29 | 2019-02-19 | 北京工商大学 | A kind of polylactic acid nano abscess foamed material and preparation method thereof |
| WO2019196320A1 (en) * | 2018-04-09 | 2019-10-17 | 山东大学 | Method for improving foaming rate of polylactic acid through pre-isothermal cold crystallization treatment |
| CN115093601A (en) * | 2022-08-04 | 2022-09-23 | 台州玉米环保科技有限公司 | Preparation method of anti-falling PP milk teacup |
| CN116323770A (en) * | 2020-07-31 | 2023-06-23 | 株式会社理光 | Foam, foam sheet, product, and method for producing foam |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101265355A (en) * | 2007-03-16 | 2008-09-17 | 东丽纤维研究所（中国）有限公司 | Polylactic acid mixture and forming articles thereof |
| CN105732995A (en) * | 2016-04-16 | 2016-07-06 | 宁波高新区优合塑料制品有限公司 | Cold crystallization production technology for low-cost high heat-resistance polylactic acid product |
| CN107722581A (en) * | 2017-10-27 | 2018-02-23 | 北京工商大学 | A kind of polylactic acid alloy expanded material of high foamability and preparation method thereof |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| ES2906024T3 (en) * | 2014-12-22 | 2022-04-12 | Purac Biochem Bv | Molded polylactide article and method of preparation |
| CN106967280A (en) * | 2017-04-21 | 2017-07-21 | 桑德（天津）再生资源投资控股有限公司 | A kind of preparation method of the fully biodegradable foamed material of high magnification |
| CN108409985B (en) * | 2018-04-09 | 2020-12-29 | 山东大学 | Method for improving foaming ratio of polylactic acid through pre-isothermal cold crystallization treatment |
-
2018
- 2018-04-09 CN CN201810312851.8A patent/CN108409985B/en active Active
- 2018-08-31 WO PCT/CN2018/103673 patent/WO2019196320A1/en active Application Filing
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101265355A (en) * | 2007-03-16 | 2008-09-17 | 东丽纤维研究所（中国）有限公司 | Polylactic acid mixture and forming articles thereof |
| CN105732995A (en) * | 2016-04-16 | 2016-07-06 | 宁波高新区优合塑料制品有限公司 | Cold crystallization production technology for low-cost high heat-resistance polylactic acid product |
| CN107722581A (en) * | 2017-10-27 | 2018-02-23 | 北京工商大学 | A kind of polylactic acid alloy expanded material of high foamability and preparation method thereof |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2019196320A1 (en) * | 2018-04-09 | 2019-10-17 | 山东大学 | Method for improving foaming rate of polylactic acid through pre-isothermal cold crystallization treatment |
| CN109354847A (en) * | 2018-10-29 | 2019-02-19 | 北京工商大学 | A kind of polylactic acid nano abscess foamed material and preparation method thereof |
| CN116323770A (en) * | 2020-07-31 | 2023-06-23 | 株式会社理光 | Foam, foam sheet, product, and method for producing foam |
| CN115093601A (en) * | 2022-08-04 | 2022-09-23 | 台州玉米环保科技有限公司 | Preparation method of anti-falling PP milk teacup |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2019196320A1 (en) | 2019-10-17 |
| CN108409985B (en) | 2020-12-29 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108409985A (en) | A method of it is handled by pre- isothermal cold crystallization and improves expanded polylactic acid multiplying power | |
| Lu et al. | Bio-based poly (lactic acid)/high-density polyethylene blends as shape-stabilized phase change material for thermal energy storage applications | |
| Matuana et al. | Cell morphology of extrusion foamed poly (lactic acid) using endothermic chemical foaming agent | |
| CN105131538B (en) | A kind of PET foaming products and preparation method thereof | |
| Wang et al. | Effect of polytetrafluoroethylene on the foaming behaviors of linear polypropylene in continuous extrusion | |
| Tang et al. | Autoclave preparation of expanded polypropylene/poly (lactic acid) blend bead foams with a batch foaming process | |
| Huang et al. | Mechanical properties, crystallization characteristics, and foaming behavior of polytetrafluoroethylene‐reinforced poly (lactic acid) composites | |
| CN105273368B (en) | A kind of expandable PET resin and its production and use | |
| Riahinezhad et al. | An investigation on the correlation between rheology and morphology of nanocomposite foams based on low‐density polyethylene and ethylene vinyl acetate blends | |
| Xing et al. | Preparation of microcellular cross-linked polyethylene foams by a radiation and supercritical carbon dioxide approach | |
| Qiao et al. | Non-isothermal crystallization kinetics of polypropylene/polytetrafluoroethylene fibrillated composites | |
| KR101632086B1 (en) | Extruded foams made with polylactides that have high molecular weights and high intrinsic viscosities | |
| Sun et al. | Preparation of highly interconnected porous poly (ε‐caprolactone)/poly (lactic acid) scaffolds via supercritical foaming | |
| CN102464828A (en) | Polypropylene/clay nanocomposite microcellular foam material and preparation method thereof | |
| CN104629176A (en) | Open-celled polypropylene microcellular foaming sheet and production method thereof | |
| CN113736228A (en) | High-magnification PBAT foaming bead and preparation method thereof | |
| Salmazo et al. | Influence of the irradiation dose in the cellular structure of natural rubber foams cross-linked by electron beam irradiation | |
| You et al. | A “Plasticizing-Foaming-Reinforcing” approach for creating thermally insulating PVC/polyurea blend foams with shape memory function | |
| Yin et al. | Simple and feasible strategy to fabricate microcellular poly (butylene succinate) foams by chain extension and isothermal crystallization induction | |
| CN107337801B (en) | Method for preparing high melt strength polypropylene by electron irradiation crosslinking | |
| Wang et al. | Peculiar micro and nano cell morphology of PBT/PTFE nanofibrillated composite foams of supercritical CO2 foaming induced by in-situ formed 3D PTFE nanofiber networks | |
| Shi et al. | Striking effect of carbon nanotubes on adjusting sc-CO2 foaming performance of PS/LLDPE blends and forming semi-open cellular structure | |
| CN103819885A (en) | Polylactic acid foam material and preparation method thereof | |
| Wang et al. | Preparation and mechanism of lightweight wood fiber/poly (lactic acid) composites | |
| CN107266838A (en) | A kind of thermoplastic polyvinyl alcohol water-soluble compound and preparation method thereof |
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 | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |