CN117341224A - Continuous preparation method of polyglycolic acid multilayer film and obtained multilayer film - Google Patents
Continuous preparation method of polyglycolic acid multilayer film and obtained multilayer film Download PDFInfo
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- CN117341224A CN117341224A CN202210740869.4A CN202210740869A CN117341224A CN 117341224 A CN117341224 A CN 117341224A CN 202210740869 A CN202210740869 A CN 202210740869A CN 117341224 A CN117341224 A CN 117341224A
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- polyglycolic acid
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- 229920000954 Polyglycolide Polymers 0.000 title claims abstract description 127
- 239000004633 polyglycolic acid Substances 0.000 title claims abstract description 127
- 238000002360 preparation method Methods 0.000 title description 17
- 238000000034 method Methods 0.000 claims abstract description 42
- 229920000229 biodegradable polyester Polymers 0.000 claims abstract description 38
- 239000004622 biodegradable polyester Substances 0.000 claims abstract description 38
- 238000007731 hot pressing Methods 0.000 claims abstract description 32
- 238000002844 melting Methods 0.000 claims abstract description 30
- 230000008018 melting Effects 0.000 claims abstract description 26
- 238000005266 casting Methods 0.000 claims abstract description 15
- 238000001816 cooling Methods 0.000 claims abstract description 15
- 238000010924 continuous production Methods 0.000 claims abstract description 14
- 238000012360 testing method Methods 0.000 claims description 17
- 229920001634 Copolyester Polymers 0.000 claims description 16
- -1 polybutylene Polymers 0.000 claims description 16
- 238000001125 extrusion Methods 0.000 claims description 10
- 239000002253 acid Substances 0.000 claims description 9
- 239000004626 polylactic acid Substances 0.000 claims description 9
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims description 8
- 229920001748 polybutylene Polymers 0.000 claims description 8
- 239000005014 poly(hydroxyalkanoate) Substances 0.000 claims description 7
- 229920001610 polycaprolactone Polymers 0.000 claims description 7
- 239000004632 polycaprolactone Substances 0.000 claims description 7
- 229920000903 polyhydroxyalkanoate Polymers 0.000 claims description 7
- 229920000747 poly(lactic acid) Polymers 0.000 claims description 6
- 239000000155 melt Substances 0.000 claims description 5
- 239000004698 Polyethylene Substances 0.000 claims description 4
- 239000001569 carbon dioxide Substances 0.000 claims description 4
- 229910002092 carbon dioxide Inorganic materials 0.000 claims description 4
- 229920006238 degradable plastic Polymers 0.000 claims description 4
- 238000004806 packaging method and process Methods 0.000 claims description 4
- 229920000573 polyethylene Polymers 0.000 claims description 4
- 230000004888 barrier function Effects 0.000 claims description 3
- 150000002009 diols Chemical class 0.000 claims description 3
- 229920002961 polybutylene succinate Polymers 0.000 claims description 3
- 239000004631 polybutylene succinate Substances 0.000 claims description 3
- 229920009537 polybutylene succinate adipate Polymers 0.000 claims description 3
- 239000004630 polybutylene succinate adipate Substances 0.000 claims description 3
- 238000009826 distribution Methods 0.000 claims description 2
- 230000004927 fusion Effects 0.000 claims description 2
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims 1
- 229920005989 resin Polymers 0.000 abstract description 21
- 239000011347 resin Substances 0.000 abstract description 21
- 239000000463 material Substances 0.000 abstract description 7
- 230000015556 catabolic process Effects 0.000 abstract description 5
- 238000006731 degradation reaction Methods 0.000 abstract description 5
- 239000000853 adhesive Substances 0.000 abstract description 3
- 230000001070 adhesive effect Effects 0.000 abstract description 3
- 238000013329 compounding Methods 0.000 abstract description 3
- 229920006167 biodegradable resin Polymers 0.000 abstract description 2
- 239000002245 particle Substances 0.000 description 20
- 238000005096 rolling process Methods 0.000 description 12
- 238000002425 crystallisation Methods 0.000 description 9
- 230000008025 crystallization Effects 0.000 description 9
- 239000002131 composite material Substances 0.000 description 7
- LYCAIKOWRPUZTN-UHFFFAOYSA-N Ethylene glycol Chemical compound OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 6
- 239000012528 membrane Substances 0.000 description 6
- 230000000052 comparative effect Effects 0.000 description 5
- AEMRFAOFKBGASW-UHFFFAOYSA-N Glycolic acid Chemical compound OCC(O)=O AEMRFAOFKBGASW-UHFFFAOYSA-N 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 125000003118 aryl group Chemical group 0.000 description 3
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 3
- 238000007789 sealing Methods 0.000 description 3
- PUPZLCDOIYMWBV-UHFFFAOYSA-N (+/-)-1,3-Butanediol Chemical compound CC(O)CCO PUPZLCDOIYMWBV-UHFFFAOYSA-N 0.000 description 2
- RKDVKSZUMVYZHH-UHFFFAOYSA-N 1,4-dioxane-2,5-dione Chemical group O=C1COC(=O)CO1 RKDVKSZUMVYZHH-UHFFFAOYSA-N 0.000 description 2
- 238000010521 absorption reaction Methods 0.000 description 2
- 125000001931 aliphatic group Chemical group 0.000 description 2
- 229920003232 aliphatic polyester Polymers 0.000 description 2
- 125000004432 carbon atom Chemical group C* 0.000 description 2
- 239000000969 carrier Substances 0.000 description 2
- 238000010438 heat treatment Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000002362 mulch Substances 0.000 description 2
- 239000005022 packaging material Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000012779 reinforcing material Substances 0.000 description 2
- 238000007151 ring opening polymerisation reaction Methods 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- JVTAAEKCZFNVCJ-UHFFFAOYSA-M Lactate Chemical compound CC(O)C([O-])=O JVTAAEKCZFNVCJ-UHFFFAOYSA-M 0.000 description 1
- 238000013267 controlled drug release Methods 0.000 description 1
- 238000013270 controlled release Methods 0.000 description 1
- 238000001938 differential scanning calorimetry curve Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229920006351 engineering plastic Polymers 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 238000000338 in vitro Methods 0.000 description 1
- 238000001727 in vivo Methods 0.000 description 1
- 238000002074 melt spinning Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000012785 packaging film Substances 0.000 description 1
- 229920006280 packaging film Polymers 0.000 description 1
- 238000012643 polycondensation polymerization Methods 0.000 description 1
- 238000006068 polycondensation reaction Methods 0.000 description 1
- 239000002861 polymer material Substances 0.000 description 1
- 229920005862 polyol Polymers 0.000 description 1
- 150000003077 polyols Chemical class 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 238000009987 spinning Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Classifications
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- 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
- 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
- B29C41/00—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor
- B29C41/24—Shaping by coating a mould, core or other substrate, i.e. by depositing material and stripping-off the shaped article; Apparatus therefor for making articles of indefinite length
-
- 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
- B29C65/00—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor
- B29C65/02—Joining or sealing of preformed parts, e.g. welding of plastics materials; Apparatus therefor by heating, with or without pressure
-
- 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
- C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
- C08J5/18—Manufacture of films or sheets
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2007/00—Flat articles, e.g. films or sheets
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
- B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
- B29L2009/00—Layered products
-
- 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
- C08J2367/02—Polyesters derived from dicarboxylic acids and dihydroxy compounds
-
- 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
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W90/00—Enabling technologies or technologies with a potential or indirect contribution to greenhouse gas [GHG] emissions mitigation
- Y02W90/10—Bio-packaging, e.g. packing containers made from renewable resources or bio-plastics
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Manufacturing & Machinery (AREA)
- Materials Engineering (AREA)
- Health & Medical Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Medicinal Chemistry (AREA)
- Polymers & Plastics (AREA)
- Organic Chemistry (AREA)
- Extrusion Moulding Of Plastics Or The Like (AREA)
Abstract
The present invention relates to a continuous production method for a polyglycolic acid multilayer film and the multilayer film obtained thereby. The method comprises the steps of simultaneously extruding polyglycolic acid and biodegradable polyester respectively in parallel for casting and cooling, and then respectively dragging and converging the obtained polyglycolic acid film and biodegradable polyester film into the same hot-pressing unit for hot-pressing to obtain the multilayer film. The invention can obtain the adhesive force with other low-melting-point biodegradable resin films by controlling the crystallinity of the high-melting-point polyglycolic acid film, and has higher peel strength. The method can be used for compounding degradable resin materials with large melting point difference, and avoids the partial thermal degradation of high-melting point resin to adjacent low-melting point resin layers caused by high temperature in a multilayer coextrusion process.
Description
Technical Field
The invention relates to the field of high polymer materials, in particular to a continuous preparation method of a polyglycolic acid multilayer film, and particularly relates to a polyglycolic acid film with a high melting point and a biodegradable resin film blend multilayer film with a low melting point, and an obtained multilayer film and application.
Background
Polyglycolic acid (PGA), which is the simplest linear aliphatic polyester, is a typical high crystallinity polymer that is lattice stable and has a relatively high melting point. In recent years, PGA has been widely focused and used in the fields of medical sutures, controlled drug release carriers, fracture fixation materials, tissue engineering scaffolds, reinforcing materials, oil fields and the like, due to its excellent biodegradability, rapid degradation speed, good biocompatibility, good bioresorbability, high mechanical strength (certain index vs. standard engineering plastics) and the like. However, PGA has a high melting point, a narrow processing temperature, a high crystallinity, and an excessively high degradation rate, which seriously affects its use in processing and above materials.
Biodegradable polyester resins have been widely used in disposable packaging materials, particularly shopping bags, express packaging bags, and agricultural mulch films in recent years due to their excellent biodegradability. Specifically comprises polylactic acid (PLA), polyhydroxyalkanoates (PHA), polycaprolactone (PCL), carbon dioxide-based degradable plastics (PPC), dibasic acid glycol copolyester and the like.
Disclosure of Invention
One of the technical problems to be solved by the invention is that a pure polyglycolic acid film and a biodegradable polyester resin film in the prior art have poor heat sealing performance and high melting point temperature difference, and a continuous preparation method of a composite film of polyglycolic acid with high melting point and biodegradable polyester resin with low melting point is provided. The inventors have found that by this process a continuous multilayer (. Gtoreq.2 layers) biodegradable composite film can be prepared. The method can be used for compounding degradable resin materials with large melting point difference (more than 15 ℃), and avoids partial thermal degradation of the low-melting-point resin layer caused by high temperature when one oral film is converged in a multilayer coextrusion process. Under the process conditions of the invention, the obtained degradable multi-layer film has excellent heat sealing performance under industrial conditions, and can be used for expanding the application of the degradable polyglycolic acid multi-layer film in the fields of barrier packaging films and the like.
The second technical problem to be solved by the invention is to provide a preparation method for continuously preparing the polyglycolic acid and biodegradable polyester resin multilayer film.
The third technical problem to be solved by the invention is to provide the polyglycolic acid and biodegradable polyester resin multilayer film product which is prepared by the continuous preparation method for the polyglycolic acid and biodegradable polyester resin multilayer film.
The fourth technical problem to be solved by the invention is to provide an application method which is applicable to the polyglycolic acid and biodegradable polyester resin multilayer film and corresponds to one of the technical problems or the third technical problem.
In order to solve the technical problems, one of the purposes of the invention is to provide a continuous preparation method of a polyglycolic acid multi-layer film, which comprises the steps of simultaneously extruding and casting polyglycolic acid and biodegradable polyester respectively in parallel, cooling, respectively dragging and converging the obtained polyglycolic acid film and the obtained biodegradable polyester film into a same hot-pressing unit for hot-pressing, and finally pulling out to obtain the multi-layer film.
In the continuous preparation method, the adhesive force between the high-melting-point polyglycolic acid film and the low-melting-point biodegradable polyester film in the hot pressing link is realized by controlling the crystallinity of the high-melting-point polyglycolic acid film before entering a hot pressing unit, wherein the crystallinity of the polyglycolic acid film entering the hot pressing unit is 1-30%, preferably 1-17%.
Wherein, the polyglycolic acid can be prepared by glycolide ring-opening polymerization or glycolic acid or methyl glycolate polycondensation polymerization; preferably, the polyglycolic acid may have an intrinsic viscosity of 0.9 to 4dl/g, and more preferably 0.9 to 2dl/g.
The fusion temperature range of the polyglycolic acid resin is 200-235 ℃ when the polyglycolic acid resin is tested at the temperature rise/fall rate of 10/min.
The crystallinity of the polyglycolic acid resin is 1-70%.
The weight average molecular weight of the polyglycolic acid is 50000 ～ 1000000g/mol, preferably 100000 ～ 500000g/mol.
The molecular weight distribution index of the polyglycolic acid is 0.5 to 15.0, preferably 1.5 to 3.0.
The biodegradable polyester is selected from one or a mixture of two or more of polylactic acid (PLA), polyhydroxyalkanoates (PHA), polycaprolactone (PCL), carbon dioxide-based degradable plastics (PPC) and dibasic acid glycol copolyester.
Wherein the dibasic acid diol copolyester is preferably alpha, omega-aliphatic diacid or aliphatic diacid containing 2-18 main chain carbon atoms and copolyester formed by condensing at least one aromatic dibasic acid and at least one aliphatic diol.
The diacid-diol copolyester includes, but is not limited to, one or more of polybutylene terephthalate-co-adipate (PBAT), polyethylene terephthalate-co-adipate (PBST), polybutylene terephthalate-co-succinate (PBST), polybutylene succinate-adipate (PBSA), polybutylene succinate (PBS); preferably, the diacid polyol copolyester is one or more of polybutylene terephthalate-co-adipate (PBAT), polybutylene terephthalate-co-succinate (PBST).
The melting point of the biodegradable polyester resin is less than or equal to 180 ℃.
The melt index of the biodegradable polyester resin is 2-20 g/10min, more preferably 2-15 g/10min under the test condition of 190 ℃ and 2.16 kg.
The difference between the melting point of the biodegradable polyester and the melting point of the polyglycolic acid is more than or equal to 15 ℃, preferably more than or equal to 20 ℃.
In the continuous production method of the present invention, extrusion casting may be performed by using a device generally known in the art, preferably a single screw extruder.
In the continuous preparation method, polyglycolic acid and biodegradable polyester are extruded and cast into films by two or more extruders simultaneously in parallel, and then cooled by cooling rolls respectively.
In extrusion casting of the continuous preparation method, the melt extrusion temperature of polyglycolic acid is 200-255 ℃, and the mouth film temperature is preferably 210-235 ℃.
In the extrusion casting of the continuous preparation method of the invention, the cooling temperature of the polyglycolic acid film is 10-60 ℃, preferably 10-40 ℃. The polyglycolic acid film obtained by casting is cooled by a cooling roll having a temperature of 10 to 60℃and preferably 10 to 40℃and, for example, 10℃15℃20℃25℃30℃35℃40℃45℃50℃55℃60 ℃.
In the continuous production method of the present invention, the polyglycolic acid film obtained after cooling has a crystallinity of 1 to 30%, preferably 1 to 17%, more preferably 9 to 17%.
In extrusion casting of the continuous preparation method, the melt extrusion temperature of the biodegradable polyester is 100-180 ℃, preferably 120-180 ℃; the rotation speed is 30 to 300rpm, preferably 30 to 200rpm.
In the continuous preparation method, the temperature of the hot pressing unit is 50-200 ℃, preferably 100-160 ℃; the hot pressing time is 0.1-5 min, preferably 0.1-3 min; the hot-pressing pressure is 2 to 200kPa, preferably 5 to 100kPa.
In the continuous preparation method, the hot pressing unit adopts a hot pressing roller, and the hot pressing roller can be a round roller or a square roller.
In the continuous production method of the present invention, the thicknesses of the polyglycolic acid film and the biodegradable polyester film to be obtained are not particularly limited, and may be a usual thickness or may be adjusted according to practical applications.
According to a preferred embodiment of the present invention, the continuous preparation method of the present invention may comprise the steps of:
1) And (3) casting the high-melting-point polyglycolic acid into a film in a single-screw extruder, cooling the film by a cooling roller after the film is discharged, and then continuously drawing under the action of a drawing roller.
2) Meanwhile, the biodegradable polyester is cast from another single screw flow extruder to prepare a film, and is pulled under the action of a pulling roll after passing through an oral film.
3) And (3) merging the obtained biodegradable polyester film and the polyglycolic acid film into the same hot-pressing unit under the traction effect, and hot-pressing to obtain the composite multilayer film.
In the step 3), the high-melting-point polyglycolic acid film and the low-melting-point biodegradable polyester film may be laminated and compounded in two, three or more layers.
For example, in the three-layer composite system, a high-melting-point polyglycolic acid film and a low-melting-point biodegradable polyester film are laminated in an ABA type, BAB type, or ABC type system (a: biodegradable polyester film, B: polyglycolic acid film, C: biodegradable polyester film).
The second object of the present invention is to provide a polyglycolic acid multilayer film produced by the continuous production method of a polyglycolic acid multilayer film.
The polyglycolic acid multilayer film is a polyglycolic acid/biodegradable polyester multilayer film product and comprises a high-melting-point polyglycolic acid layer and a low-melting-point biodegradable polyester layer. The multilayer film is a two-layer or more than two-layer composite film.
It is a further object of the present invention to provide the use of said polyglycolic acid multilayer film in barrier packaging.
The preparation method of the continuous polyglycolic acid multilayer film can improve the adhesive force with other low-melting-point biodegradable polyester films (which are different from the PGA by at least 15 ℃) by controlling the crystallinity of the high-melting-point polyglycolic acid film, has higher peel strength and has certain novelty. Different from the traditional multilayer coextrusion casting process, the method adopts a single screw extruder to enable polyglycolic acid and/or biodegradable polyester to flow out of respective oral films (instead of the multilayer coextrusion converging into one oral film), obtains a polyglycolic acid film with low crystallinity by controlling the temperature of a high-melting-point polyglycolic acid cooling roller, and then is compounded with other low-melting-point biodegradable polyester casting films through the same hot-pressing unit, so that a continuous multilayer biodegradable composite film can be obtained. The method can be used for compounding degradable resin materials with large melting point difference (more than 15 ℃) as raw materials, and avoids the partial thermal degradation of high-melting point resin to adjacent low-melting point resin layers caused by high temperature in the multilayer coextrusion process.
Detailed Description
The present invention is described in detail below with reference to specific embodiments, and it should be noted that the following embodiments are only for further description of the present invention and should not be construed as limiting the scope of the present invention, and some insubstantial modifications and adjustments of the present invention by those skilled in the art from the present disclosure are still within the scope of the present invention.
The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein.
The following materials and preparation methods are briefly described as follows:
1. polyglycolic acid
Polyglycolic acid (Polyglycolic acid, PGA), also known as polyglycolic acid, is the simplest linear aliphatic polyester. PGA can be prepared by melt polycondensation of glycolic acid or ring-opening polymerization of glycolide. Polyglycolic acid is a typical high crystallinity polymer that is lattice stable and has a relatively high melting point. The relatively high crystallization rate and high crystallinity of PGA result in a brittle, high modulus, but low impact strength, and the product is extremely brittle, limiting its use.
Polyglycolic acid has excellent biodegradability, can enter a human circulatory system to be degraded in vivo and discharged out of the body, can be degraded in an in-vitro environment, and is mainly applied to the fields of medical suture lines, drug controlled release carriers, fracture fixing materials, tissue engineering scaffolds, reinforcing materials and the like. Through solution spinning and melt spinning, polyglycolic acid can be processed into surgical suture lines, has stronger tensile strength and can maintain enough time, and is suitable for wound suturing of deep tissues.
2. Biodegradable polyesters
Biodegradable polyester resins have been widely used in disposable packaging materials, particularly shopping bags, express packaging bags, and agricultural mulch films in recent years due to their excellent biodegradability. Specifically comprises one or more of polylactic acid (PLA), polyhydroxyalkanoates (PHA), polycaprolactone (PCL), carbon dioxide-based degradable plastics (PPC) and dibasic acid glycol copolyester. Wherein the dibasic acid diol copolyester is preferably alpha, omega-aliphatic diacid or aliphatic diacid containing 2-18 main chain carbon atoms and copolyester formed by condensing at least one aromatic dibasic acid and at least one aliphatic diol; more preferably one or more of polybutylene terephthalate-co-adipate, polyethylene terephthalate-co-succinate, and polybutylene terephthalate-co-succinate.
3. Polyglycolic acid blend multilayer film
1) And (3) casting the high-melting-point polyglycolic acid into a film by a single screw extruder at 200-210-220-220-230 ℃, setting the temperature of the film to 230 ℃, cooling the film by a cooling roller after passing through the film, and then continuously drawing under the action of a drawing roller. 2) And simultaneously casting the biodegradable polyester from another single screw flow extruder to prepare a film. 3) The biodegradable film is overlapped with the polyglycolic acid film after passing through the oral film and being drawn by a cold roller, and then the composite film is obtained after hot pressing by a hot pressing roller.
The raw materials used in examples and comparative examples are all commercially available.
Polyglycolic acid (PGA), produced by Corbion Purac company, has an intrinsic viscosity of 1.0-1.4 dl/g, a melting point of 200-230 ℃, and a crystallinity of 30-70%;
aliphatic aromatic copolyesters produced by BASF under the trademark BASFAliphatic aromatic copolyester PBAT particles of FC-1200 with a melting point of 120-140 ℃;
aliphatic aromatic copolyester, namely aliphatic aromatic copolyester PBST particles with the brand TS 159 produced by instrumentation chemical fiber, and the melting point of the aliphatic aromatic copolyester PBST particles is 120-140 ℃;
polylactic acid, PLA particles with the brand 4032D manufactured by Nature works, and the melting point is 150-170 ℃.
The invention performs performance measurement according to the following method:
heat seal strength test: the process software was Bluehill version 2.31, as determined by the OB/T2358-98 standard using the INSTRON model 3344 film product testing machine. The film was cut into Type 2 of ISO 527-2 standard, and placed in a Bluecard BPS-100CB constant temperature and humidity cabinet (temperature 23 ℃ C., relative humidity 50%) of Shanghai-Hemsl scientific instruments Co., ltd for 24 hours. During testing, the initial fixture spacing was 50mm and the test stretching rate was 300mm/min. And taking the heat sealing part as the center, peeling the upper film to the same position, opening the upper film to 180 degrees, clamping two sections of the pattern on two clamps of the testing machine, and extending the lower end of the pattern to the same length. Each sample was tested 5 times and averaged. The maximum load at which the test specimen breaks is read.
Film crystallinity test: measuring crystallization thermodynamic parameters of the PGA film by using a Differential Scanning Calorimeter (DSC) of the American TA company, adding about 4-8mg of the PGA film sample into a DSC sample cell, heating to 250 ℃ at a speed of 10 ℃/min, and keeping the temperature for 2min to eliminate heat history; then cooling to-50 ℃ at 10 ℃/min, and recording a cooling crystallization DSC spectrum of the film sample; then the temperature is increased to 250 ℃ at the speed of 10 ℃/min, and the crystallization melting DSC spectrum of the sample is recorded. The two DSC curves are processed to obtain crystallization thermodynamic parameters such as the crystallization temperature, the crystallization melting point, the melting heat and the like of the PGA film. Wherein the PGA film has crystallinity (X c ) Calculated according to the following formula:
x in the formula c In order to achieve a degree of crystallinity,％；△H m is the heat absorption enthalpy of melting, J/g; deltaH m100 The melting heat absorption enthalpy at the time of complete crystallization of PGA was 191.32J/g.
The invention is further illustrated by the following specific examples, but the summary of the invention is not limited to the scope of the examples shown.
Comparative example 1
The PGA particles were cast using a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE. The temperature of the screw temperature extruder in the experimental process is respectively as follows: 200 ℃,220 ℃,230 ℃,230 ℃,240 ℃,250 ℃,240 ℃,230 ℃ and 225 ℃ and the screw rotation speed is set at 200rpm. The torque range is 20-50% during steady operation. The PGA exit film (225 ℃ C.) was cooled by a chill roll and then drawn through a calender roll. The chill roll temperature was set at 80℃and the draw speed was 1.6m/min. (after DSC test, the PGA film obtained at this time had a crystallinity of 37%).
Meanwhile, PBAT particles were cast using another 2 Thermo SCIENTIFIC HAAKE PolyLab OS single screw extruders, respectively. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 140 ℃,150 ℃,150 ℃,160 ℃,170 ℃,160 ℃,150 ℃,150 ℃ and the screw rotation speed is set at 100rpm. The torque range is 10-50% during steady operation. The PBAT outlet membrane was then drawn through a calender roll at a draw speed of 1.6m/min. And then the cooled PGA film is taken as an inner layer film and an upper layer and a lower layer of PBAT film are put into a hot pressing roller for pressing, the temperature of the hot pressing roller is set to 120 ℃, the temperature of the hot pressing roller is kept for 3min under the pressure of 80kPa, and then the PGA film is rolled up by a calender roller.
[ example 1 ]
The PGA particles were cast using a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 200 ℃,220 ℃,230 ℃,230 ℃,240 ℃,250 ℃,240 ℃,230 ℃ and 225 ℃ and the screw rotation speed is set at 200rpm. The torque range is 20-50% during steady operation. The PGA exit film (225 ℃ C.) was cooled by a chill roll and then drawn through a calender roll. The chill roll temperature was set at 60℃and the draw speed was 1.6m/min. (after DSC test, the PGA film obtained at this time had a crystallinity of 27%).
Meanwhile, PBAT particles were cast using another 2 Thermo SCIENTIFIC HAAKE PolyLab OS single screw extruders, respectively. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 140 ℃,150 ℃,150 ℃,160 ℃,170 ℃,160 ℃,150 ℃,150 ℃ and the screw rotation speed is set at 100rpm. The torque range is 10-50% during steady operation. And the PBAT outlet membrane is pulled by a calender roll, and the pulling speed is 1.6m/min. And rolling the cooled PGA film serving as an inner layer film and an upper layer and a lower layer of PBAT film by a hot-press roller, wherein the temperature of the hot-press roller is set to 120 ℃, the temperature is kept for 3min under the pressure of 80kPa, and then rolling by a calender roller.
[ example 2 ]
The PGA particles were cast using a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 200 ℃,220 ℃,230 ℃,230 ℃,240 ℃,250 ℃,240 ℃,230 ℃ and 225 ℃ and the screw rotation speed is set at 200rpm. The torque range is 20-50% during steady operation. The PGA exit film (225 ℃ C.) was cooled by a chill roll and then drawn through a calender roll. The chill roll temperature was set at 60℃and the draw speed was 1.6m/min. (after DSC test, the PGA film obtained at this time had a crystallinity of 27%).
Meanwhile, PBAT particles were cast using another 2 Thermo SCIENTIFIC HAAKE PolyLab OS single screw extruders, respectively. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 140 ℃,150 ℃,150 ℃,160 ℃,170 ℃,160 ℃,150 ℃,150 ℃ and the screw rotation speed is set at 100rpm. The torque range is 10-50% during steady operation. And the PBAT outlet membrane is pulled by a calender roll, and the pulling speed is 1.6m/min. And rolling the cooled PGA film serving as an inner layer film and an upper layer and a lower layer of PBAT film by a hot-press roller, wherein the temperature of the hot-press roller is set to be 180 ℃, the pressure is 80kPa, and then rolling by a calender roller.
[ example 3 ]
The PGA particles were cast using a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 200 ℃,220 ℃,230 ℃,230 ℃,240 ℃,250 ℃,240 ℃,230 ℃ and 225 ℃ and the screw rotation speed is set at 200rpm. The torque range is 20-50% during steady operation. The PGA exit film (225 ℃ C.) was cooled by a chill roll and then drawn through a calender roll. The chill roll temperature was set at 20℃and the draw speed at 1.6m/min. (after DSC test, the PGA film obtained at this time had a crystallinity of 13%).
Meanwhile, PBAT particles were cast using another 2 Thermo SCIENTIFIC HAAKE PolyLab OS single screw extruders, respectively. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 140 ℃,150 ℃,150 ℃,160 ℃,170 ℃,160 ℃,150 ℃,150 ℃ and the screw rotation speed is set at 100rpm. The torque range is 10-50% during steady operation. And the PBAT outlet membrane is pulled by a calender roll, and the pulling speed is 1.6m/min. And then rolling the cooled PGA film into an inner layer film and an upper layer and a lower layer of PBAT film by a hot press roller, wherein the temperature of the hot press roller is set to 120 ℃, the pressure is 80kPa, and then rolling by a calender roller.
[ example 4 ]
The PGA particles were cast using a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 200 ℃,220 ℃,230 ℃,230 ℃,240 ℃,250 ℃,240 ℃,230 ℃ and 220 ℃, and the screw rotation speed is set at 200rpm. The torque range is 20-50% during steady operation. The PGA exit film (225 ℃ C.) was cooled by a chill roll and then drawn through a calender roll. The chill roll temperature was set at 20℃and the draw speed at 1.6m/min. (after DSC test, the PGA film obtained at this time had a crystallinity of 13%).
At the same time, PBST particles were each cast using another 2 Thermo SCIENTIFIC HAAKE PolyLab OS single screw extruders. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 140 ℃,150 ℃,150 ℃,160 ℃,170 ℃,160 ℃,150 ℃,150 ℃ and the screw rotation speed is set at 100rpm. The torque range is 10-50% during steady operation. And the PBST outlet membrane is pulled by a calender roll, and the pulling speed is 1.6m/min. And rolling the cooled PGA film into an inner layer film and an upper layer and a lower layer of PBST film by a hot-press roller, wherein the temperature of the hot-press roller is set to 120 ℃, the PGA film is kept for 3min under the pressure of 80kPa, and then the PGA film is rolled by a calender roller.
[ example 5 ]
The PGA particles were cast using a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 200 ℃,220 ℃,230 ℃,230 ℃,240 ℃,250 ℃,240 ℃,230 ℃ and 220 ℃, and the screw rotation speed is set at 200rpm. The torque range is 20-50% during steady operation. The PGA exit film (225 ℃ C.) was cooled by a chill roll and then drawn through a calender roll. The chill roll temperature was set at 20℃and the draw speed at 1.6m/min. (after DSC test, the PGA film obtained at this time had a crystallinity of 13%).
At this time, the PBST and PBAT particles were cast using a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE company, respectively. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 140 ℃,150 ℃,150 ℃,160 ℃,170 ℃,160 ℃,150 ℃,150 ℃ and the screw rotation speed is set at 100rpm. The torque range is 10-50% during steady operation. And the PBAT and PBST outlet films are pulled by a calender roll, wherein the pulling speed is 1.6m/min. And rolling the cooled PGA film into an inner layer film, and rolling the inner layer film, the PBST film and the PBAT film by a hot-press roller, wherein the temperature of the hot-press roller is set to 120 ℃, the pressure is 80, and then rolling the inner layer film by a calender roller.
[ example 6 ]
The PGA particles were cast by a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 200 ℃,220 ℃,230 ℃,230 ℃,240 ℃,250 ℃,240 ℃,230 ℃ and 220 ℃, and the screw rotation speed is set at 200rpm. The torque range is 20-50% during steady operation. The PGA exit film (225 ℃ C.) was cooled by a chill roll and then drawn through a calender roll. The chill roll temperature was set at 20℃and the draw speed at 1.6m/min. (after DSC test, the PGA film obtained at this time had a crystallinity of 13%).
Meanwhile, the PLA/PBAT blend particles with the mass fraction of 20/80 were cast by using a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE company. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 150 ℃,160 ℃,160 ℃,170 ℃,170 ℃,160 ℃,160 ℃,150 ℃,150 ℃ and the screw rotation speed is set at 100rpm. The torque range is 10-50% during steady operation. And the PLA/PBAT outlet film is pulled by a calender roll, and the pulling speed is 1.6m/min. And rolling the cooled PGA film into an inner layer film and a PLA/PBAT film by a hot-pressing roller, wherein the temperature of the hot-pressing roller is set to 120 ℃, the pressure is 80kPa, and then rolling by a calender roller.
[ example 7 ]
The PGA particles were cast using a PolyLab OS single screw extruder from Thermo SCIENTIFIC HAAKE. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 200 ℃,220 ℃,230 ℃,230 ℃,240 ℃,250 ℃,240 ℃,230 ℃ and 225 ℃ and the screw rotation speed is set at 200rpm. The torque range is 20-50% during steady operation. The PGA exit film (225 ℃ C.) was cooled by a chill roll and then drawn through a calender roll. The chill roll temperature was set at 40℃and the draw speed was 1.6m/min. (after DSC test, the PGA film obtained at this time had a crystallinity of 22%).
At the same time, PBST particles were each cast using another 2 Thermo SCIENTIFIC HAAKE PolyLab OS single screw extruders. The temperatures of the sections 2-11 of the screw temperature extruder in the experimental process are respectively as follows: 140 ℃,150 ℃,150 ℃,160 ℃,170 ℃,160 ℃,150 ℃,150 ℃ and the screw rotation speed is set at 100rpm. The torque range is 10-50% during steady operation. And the PBST outlet membrane is pulled by a calender roll, and the pulling speed is 1.6m/min. And then the cooled PGA film is taken as an inner layer film and is rolled up by a hot-pressing roller with the temperature of the hot-pressing roller set to 120 ℃ and kept for 3min under the pressure of 80kPa, and then is rolled up by a calender roller.
[ example 8 ]
The PGA films of examples 1 to 7 and comparative example 1 were heated at a heating rate of 10℃per minute, and the crystallization thermodynamic parameters were measured by a Differential Scanning Calorimeter (DSC) of the company TA in the United states, and the values are shown in Table 1.
TABLE 1 DSC thermal performance data for inner PGA film in multilayer film
[ example 9 ]
The multilayer films prepared in examples 1 to 7 and comparative example 1 were first subjected to constant temperature and humidity pretreatment in a 50% RH environment at 23℃for 24 hours, and spline heat resultant force property measurement was performed according to the procedure described above, and the values are shown in Table 2.
TABLE 2 seed spline Heat Fit Strength for examples 1-7 and comparative example 1
Claims (10)
1. A continuous process for preparing multi-layer polyglycolic acid film includes such steps as parallelly extruding polyglycolic acid and biodegradable polyester, casting, cooling, and hot pressing.
2. The continuous production method according to claim 1, characterized in that:
the intrinsic viscosity of the polyglycolic acid is 0.9 to 4dl/g, preferably 0.9 to 2dl/g;
the fusion temperature of the polyglycolic acid is 200-235 ℃ when the polyglycolic acid is tested at the speed of 10/min;
the crystallinity of the polyglycolic acid is 1-70%;
the weight average molecular weight of the polyglycolic acid is 50000 ～ 1000000g/mol, preferably 100000 ～ 500000g/mol;
the molecular weight distribution index of the polyglycolic acid is 0.5 to 15.0, preferably 1.5 to 3.0.
3. The continuous production method according to claim 1, characterized in that:
the biodegradable polyester is at least one selected from polylactic acid, polyhydroxyalkanoates, polycaprolactone, carbon dioxide-based degradable plastics and dibasic acid diol copolyester;
wherein the dibasic acid dihydric alcohol copolyester is preferably at least one selected from polybutylene terephthalate-co-adipate, polyethylene terephthalate-co-adipate, polybutylene terephthalate-co-succinate, polyethylene terephthalate-co-succinate, polybutylene succinate-adipate and polybutylene succinate.
4. The continuous production method according to claim 1, characterized in that:
the melt index of the biodegradable polyester is 2-20 g/10min, preferably 2-15 g/10min, under the test condition of 190 ℃ and 2.16 kg;
the melting point of the biodegradable polyester differs from the melting point of the polyglycolic acid by 15 ℃ or more.
5. The continuous production method according to claim 1, characterized in that:
in the extrusion casting, the melt extrusion temperature of polyglycolic acid is 200-255 ℃, wherein the mouth film temperature is preferably 210-235 ℃;
the cooling temperature of the polyglycolic acid film is 10 to 60 ℃, preferably 10 to 40 ℃.
6. The continuous production method according to claim 1, characterized in that:
the crystallinity of the polyglycolic acid film is 1 to 30%, preferably 1 to 17%.
7. The continuous production method according to claim 1, characterized in that:
in the extrusion casting, the melting extrusion temperature of the biodegradable polyester is 100-180 ℃; the rotation speed is 30 to 300rpm, preferably 30 to 200rpm.
8. The continuous production method according to claim 1, characterized in that:
the temperature of the hot pressing unit is 50-200 ℃, preferably 100-160 ℃; the hot pressing time is 0.1-5 min, preferably 0.1-3 min; the hot-pressing pressure is 2 to 200kPa, preferably 5 to 100kPa.
The hot pressing unit adopts a hot pressing roller, and the hot pressing roller is preferably a round roller or a square roller.
9. The polyglycolic acid multilayer film obtained by the continuous production process according to any one of claims 1 to 8.
10. Use of the polyglycolic acid multilayer film of claim 9 in barrier packaging.
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