KR20130110777A - Polylactide block-coplymerized lactide with polyalkylene glycol having high molecular weight - Google Patents

Abstract

PURPOSE: A manufacturing method of a block-copolymerized polylactide manufactures the block-copolymerized polylactide of polyalkylene glycol and lactide with a high molecular weight and improved flexibility and processability without the leakage of unreacted polyalkylene glycol. CONSTITUTION: A polylactide of high molecular weight polyalkylene glycol and lactide is a block-copolymerized polylactide and has a number average molecular weight of 80,000-500,000 daltons. The sodium ion content of the polyalkylene glycol is 130 ppm or less. A manufacturing method of the block-copolymerized polylactide of the polyalkylene glycol and lactide comprises a step of pre-polymerizing polyalkylene glycol lactide and a step of conducting a second polymerization by inputting a chain extender.

Description

Polylactide block-coplymerized lactide with polyalkylene glycol having high molecular weight

The present invention relates to a block copolymerized polylactide of high molecular weight polyalkylene glycol and lactide, and more particularly, to extrudability and handleability prepared by introducing a chain extender into the polyalkylene glycol and lactide copolymer. It relates to a block copolymerized polylactide of this excellent high molecular weight polyalkylene glycol and lactide.

Conventionally, plastic wastes have been mainly treated by incineration or landfill, but there have been problems such as environmental pollution due to generation and discharge of harmful by-products by incineration, reduction of landfills, and even illegal disposal. As the social concern about the treatment of plastic wastes increases, research and development of plastics that can be biodegraded by enzymes or microorganisms is rapidly progressing.

As biodegradable polymers, polyhydroxybutyrate, polycaprolactone, polylactide and aliphatic polyester are known as biodegradable polymers. Double polylactide is the most developed to replace the existing plastic.

Among these applications, when polylactide is made into a film, there is a feeling that it is too hard compared to a conventional plastic film. In other words, the lack of flexibility. Insufficient flexibility raises the problem of being noisy when handled with conventional films and / or envelopes when made from packaging films and / or envelopes.

Korean Patent No. 145138 discloses a method for producing a high molecular weight polylactide by ring-opening polymerization of a lactide using a tetrahydric or higher polyhydric alcohol, and biodegradation of a star-shaped molecular structure produced by the method. Sex polylactide is described. Herein, the polyhydric alcohol having four or more hydroxyl groups, for example, pentaerythritol, dipentaerythritol, tripentaerythritol, polyhydroxyalkyl methacrylate, polyalcohol and the like is 0.001 to 0.5 mol% based on lactide. It can be used as a general purpose biodegradable material because of its high molecular weight and low melt viscosity, which can be used as a general-purpose biodegradable material, and is widely used as a bioabsorbable material, a slow release matrix of pharmaceuticals, pharmaceuticals, and agricultural films. Polylactide is provided. However, even in the case of such polylactide, unreacted substances are leaked or flexibility is a problem.

In addition, Japanese Patent Publication No. 2009-185227 discloses an example of polymerizing polyethylene glycol block copolymerized lactide by reacting polyethylene glycol having a number average molecular weight of 8000 daltons with lactide in the case of plasticizer S1. The molecular weight is expected to be around 13000 daltons. Therefore, when this molecular weight is low, since extrusion property is not good, it becomes a problem at the time of melt extrusion molding.

As described above, in the case of the conventional polylactide, there is a problem in that it is difficult to manufacture a biodegradable resin having excellent flexibility and excellent flexibility without the outflow of unreacted polymer.

In order to improve this, the lactide was first reacted to make polylactide, and then, a polylactide polyethylene glycol block copolymer was prepared by reacting polylactide with polyethylene glycol which is a carboxyl group. In this case, if the molecular weight is a little low, an additional chain extender may be used. However, when the polyethyleneglycol block copolymerized polylactide is melt-extruded again into a sheet and then made into a film, a problem may occur in which unreacted polyethyleneglycol leaks to the film surface.

In order to improve this conventional problem, the present inventors have long research, polyalkylene glycol and lactide can be prepared into a polylactide copolymer resin containing a high molecular weight polyalkylene glycol by adding a chain extender. It was found that the present invention was completed.

Accordingly, an object of the present invention is to provide a block copolymerized polylactide of a high molecular weight polyalkylene glycol and lactide, including a chain extender, having a number average molecular weight of 80,000 daltons or more, and having excellent extrudability and handleability.

Another object of the present invention is to provide a method for preparing block copolymerized polylactide of high molecular weight polyalkylene glycol and lactide using a chain extender after prepolymerization of polyalkylene glycol and lactide.

In order to solve the above problems, the present invention is a block copolymer of a high molecular weight polyalkylene glycol and lactide of a polylactide containing a chain extender and a polyalkylene glycol block copolymerized polystyrene is a number average molecular weight of 80,000 dalton or more Provide polylactide.

In addition, the present invention is a block copolymerization of high molecular weight polyalkylene glycol and lactide comprising the first prepolymerization of polyalkylene glycol and lactide, and the second polymerization by adding a chain extender Provided are methods for preparing polylactide.

According to the present invention, by block copolymerizing polyalkylene glycol and lactide using a chain extender, the flexibility is excellent, the processability is improved, and the extrudability and the handleability are excellent.

In addition, the present invention has the effect of producing a block copolymerized polylactide of high molecular weight polyalkylene glycol and lactide without the outflow of unreacted polyalkylene glycol by a simple method.

Hereinafter, the present invention will be described in detail as one embodiment.

The present invention relates to a block copolymerized polylactide of high molecular weight polyalkylene glycol and lactide, first prepolymerized with polyalkylene glycol and lactide, and then polymerized with a chain extender.

In order to manufacture the block copolymerized polylactide containing the high molecular weight polyalkylene glycol of the present invention, it is preferable to first select a suitable copolymerized monomer other than lactide. The copolymer monomer used in the present invention is preferably selected to be able to improve the hardness of the polylactide film suitable for the purpose of the present invention.

Preferred copolymer monomers suitable for the purposes of the present invention are characterized by the use of polyalkylene glycols. Examples of the polyalkylene glycol used in the present invention include polyethylene glycol, polyalkylene glycol, polypropylene glycol, polyoxyethylene polyoxypropylene glycol (polyoxyethylene polyoxypropylene block polymer), polytetramethylene ether glycol, and the like. May be used.

The polyalkylene glycol used in the present invention preferably has a number average molecular weight of 2000 dalton or more, preferably 2000 to 50000 daltons. If the molecular weight is less than 2000 daltons, a greater amount of polyalkylene glycol must be added to secure flexibility, which increases the number of hydroxyl groups at both ends of the polyalkylene glycol, thereby increasing the molecular weight of the block copolymer. There is a problem that is difficult to produce polylactide. More preferably, the molecular weight of the polyalkylene glycol is preferably 5000 dalton or more. Even better molecular weight of polyalkylene glycol is the case where it is set to 8000 dalton or more. The reason why the molecular weight of the polyalkylene glycol is selected in this way is that the higher the molecular weight, the higher the molecular weight of the block copolymer of polyalkylene glycol / polylactide can be. However, the molecular weight is larger than 50000dalton is difficult to use due to the lowering of the reactivity.

In order to prepare the block copolymerized polylactide including the polyalkylene glycol of the present invention, it is preferable to add 5 wt% or more and 80 wt% or less of the polyalkylene glycol based on the sum of all raw materials participating in the reaction. When the content of the polyalkylene glycol is less than 5% by weight, sufficient flexibility cannot be imparted, and when the content of the polyalkylene glycol exceeds 80% by weight, it is difficult to increase the molecular weight of the block copolymerized polylactide. The content of the polyalkylene glycol contained in the polyalkylene glycol block copolymerized polylactide of the present invention is preferably set to 10 wt% or more and 70 wt% or less. More preferably, the polyalkylene glycol content to be used is 20% by weight or more and 60% or less.

The reason for setting the polyalkylene glycol input amount is that as the content of the polyalkylene glycol increases, it is difficult to increase the molecular weight of the polyalkylene glycol block copolymerized polylactide.

As pointed out as a problem in the prior art Japanese Patent Publication No. 2009-185227, it is preferable that the molecular weight of the final reaction product is low because the extrudability is not good when the final reaction product is low. .

Therefore, in the present invention, it is preferable to use a polyalkylene glycol having a high content of 10% by weight or more, preferably 20% by weight or more, and a high molecular weight polyalkylene glycol block copolymerized polylactide of 80,000 dalton or more can be prepared. .

In order to manufacture the copolymer polylactide excellent in the extrudability and handleability which are aimed at by this invention, it is preferable to manufacture the block copolymer polylactide whose number average molecular weight is 80,000 dalton or more. Preferably, a block copolymer having a number average molecular weight of at least 90,000 daltons, more preferably at least 100,000 daltons, is preferably prepared.

If the number average molecular weight is less than 80,000 dalton, it is difficult to form a sheet in a T-Die during melt extrusion, and odor due to thermal decomposition of oligomers is likely to occur.

In the present invention, even if a high content of polyalkylene glycol is used, a chain extender is used to prepare a high molecular weight polyalkylene glycol block copolymerized poly ligtard.

The method using the chain extender of the present invention, i.e., the production method basically includes a first prepolymerization of polyalkylene glycol and lactide, and a second polymerization by adding a chain extender thereto. By the method, block copolymerized polylactide of high molecular weight polyalkylene glycol and lactide can be prepared.

In one embodiment of the present invention, the second embodiment may be prepared by directly introducing a chain extender into the polymerization reactor in the second polymerization step to prepare a high molecular weight polyalkylene glycol block copolymerized polylactide, In another embodiment, the molecular weight is increased by preparing a chip after the preliminary prepolymerization step, and then introducing a chain extender during extrusion using a twin screw extruder to extrude again in the process of extruding it in the second polymerization step. It is also possible to prepare block copolymerized polylactide of high molecular weight polyalkylene glycol and lactide by increasing the method.

In the present invention, a strand cutting method may be used to make the polymer of the polyalkylene glycol block copolymerized lactide into chips, and if the molecular weight of the resin is low, it is difficult to form the strand when discharged from the polymerization reactor. Can be chipped by (underwater cutting).

When the first prepolymerized chip is again extended through a twin screw extruder (TEX), the first prepolymerized chip and the chain extender may be mixed at an appropriate ratio to increase the molecular weight.

In the reaction between the chain extender of the present invention and the polyalkylene glycol block copolymerized polylactide, the terminal group of the polyalkylene glycol block copolymerized polylactide is a hydroxyl group or a carboxyl group, and the terminal hydroxyl group or carboxyl group is chained. The molecular weight is increased by reacting with an epoxy group, an isocyanate group, a carbodiimide group, an oxazoline group, and a caprolactam of the extender.

The content of the chain extender used in the present invention is characterized by using less than 5% by weight based on the total mixture, that is, the final chip. If it is used more than 5% by weight, the color of the polymer is deteriorated and gelation phenomenon occurs, so it is preferable to use 5% by weight or less. It is preferable to use 4 wt% or less, and more preferably 3 wt% or less.

As the type of the polymer chain extender of the present invention, at least one selected from epoxy, carbodiimide, oxazoline, caprolactam and isocyanate may be used. Epoxy resins include styrene acrylic copolymers such as ASF4368S, ADR4370S and ADR4368CS from BASF, ERL4221 from TedPella Inc., and 1,4-butanediol diglycidyl ether. Carbodiimide-based carbodiimide (LA-1, HMV-8CA, etc.), and oxazoline-based allinco (ALLINCO) 1, 3-phenylene bisoxazoline (PBO), and caprolactam-based carbonyl biscaprolactam (CBC) and the like, and isocyanate-based hexamethylene diisocyanate (Hexamethylene-1,6-diisocyanate) , 4,4'-methylenebis (phenylisocyanate), 4,4'-Methylenebis (phenyl isocyanate), dicyclohexylmethane-4,4'-diisocyanate (Dicyclohexylmethane-4,4'-diisocyanate), isophorone Diisocyanate, and the like.

The number average molecular weight of the final polylactide resin produced by chain linking of polyalkylene glycol block copolymerized polylactide and polylactide by a chain extender is preferably 80,000 daltons or more. Preferably the number average molecular weight is 90,000 daltons or more, more preferably 100,000 or more daltons or more resin. If the number average molecular weight is less than 80,000 dalton, it is difficult to form a sheet in a T-Die during melt extrusion, and odor due to thermal decomposition of oligomers is likely to occur. In the present invention, a polyalkylene glycol polylactide resin having a number average molecular weight of 80,000 to 500,000 daltons can be obtained.

In the present invention, a high molecular weight target product is prepared by polymerizing a polyalkylene glycol block copolymerized polylactide containing a high content of polyalkylene glycol.

In the first prepolymerization step of the polyalkylene glycol and lactide of the present invention, a polyalkylene glycol having a sodium ion content of 130 ppm or less is used. There are many metal ions in polyalkylene glycols. For example, aluminum (Al), calcium (Ca), iron (Fe), potassium (K), lithium (Li), magnesium (Mg), sodium (Na), and the like. In particular, the content of sodium element has a great influence on the polyalkylene glycol / polylactide block copolymerization reaction.

According to the present invention, when the sodium element exceeds 130 ppm, the polymerization reaction of the polyalkylene glycol and lactide is not good, and thus, it is difficult to prepare a high molecular weight polyalkylene glycol-block copolymerized polylactide. This is because there is a relatively negatively charged strong base in the presence of excess sodium, and if a strong base is left in the alkylene glycol, it reacts with lactide, resulting in a high degree of polyalkylene glycol / It becomes difficult to make lactide block copolymers. Since sodium does not participate in the reaction, the sodium ion content of the highly polymerized polyalkylene glycol / lactide block copolymer prepared in the present invention is also preferably 130 ppm or less.

In this invention, it is preferable that lactic acid is 0.40 mol% or less in the lactide used in manufacture of polyalkylene glycol block copolymerization polylactide. If the content of lactic acid in the lactide exceeds 0.40 mol%, the reaction rate is very slow and the molecular weight does not increase very much. Such lactic acid can also be found in the final film made of polylactide. Even if the polyalkylene glycol block copolymerized polylactide is manufactured into a film through a process of sheet forming, stretching, and heat setting, the lactic acid is still present in the film. do. Of course, even when the polyalkylene glycol block copolymerized polylactide and polylactide are blended for extrusion sheet molding, stretching, and heat setting, the content of lactic acid in the film is only slightly reduced, but is still present.

According to the present invention, the raw material is dried in the stage of the first prepolymerization to sufficiently remove the moisture in the polyalkylene glycol. The drying method is most preferably a method of vacuum drying at 50 ℃ ~ 150 ℃. It is also preferable to dry the lactide to be used, but it is preferable to perform vacuum drying at a lactide melting point (95 ° C.) or less for the drying temperature of the lactide. It is preferable to dry the moisture content after drying of the polyalkylene glycol and lactide as the raw material components to 500 ppm or less, more preferably to 100 ppm or less, and more preferably to 50 ppm or less. If the drying temperature exceeds the melting point of the lactide, the polymerization reaction in the lactide proceeds, so that a block copolymer of polyalkylene glycol / polylactide of high degree of polymerization cannot be obtained, and polyalkylene glycol and / or lac When the water content in the Tid exceeds 500 ppm, the residual water reacts first with the lactide, and thus a low molecular weight polyalkylene glycol / polylactide block copolymer is obtained.

Therefore, the polymerization degree of the high-polymerization polyalkylene glycol / lactide block copolymer composition prepared according to the present invention under the above conditions has a number average molecular weight of 80,000 daltons or more, preferably a number average molecular weight of 90,000 daltons or more, more Preferably, the number average molecular weight may be manufactured to 100,000 daltons or more.

When preparing the polyalkylene glycol block copolymerized polylactide of the present invention, when the reaction temperature is less than 150 ° C, the reaction rate is too slow, and when the reaction temperature is 190 ° C or higher, the color tone of the polyalkylene glycol block copolymerized polylactide is yellow. Since a problem arises, it is preferable that reaction temperature is 150 degreeC or more and less than 190 degreeC, and the color tone of the resin manufactured in this way or the film made from this resin should have a hue b value below 10.

As a polymerization catalyst for preparing the polyalkylene glycol block copolymerized polylactide of the present invention, tin dichloride (SnCl ₂ ), tin tetrachloride (SnCl ₄ ), aluminum alkoxides, tin alkoxides, Catalysts such as zinc alkoxides, tin oxide (SnO), tin octoate (Sn (octoate) ₂ , octylate), calcium stearates and magnesium stearates can be used. There is no restriction in particular.

The catalyst content required to prepare the copolymerized polylactide of the present invention is preferably 0.005% by weight or more and 0.2% by weight or less based on the total reactants. If the catalyst content is less than 0.005% by weight of the total reactants, the productivity is low because the reaction rate is too slow. When the catalyst content exceeds 0.2% by weight, the reaction rate is high, but problems such as molecular weight reduction and toxic gas generation may occur due to the reverse reaction caused by the catalyst during extrusion after the chip is formed. Used catalyst dosage can be detected by ICP analysis.

When producing the polylactide-based resins and / or films of the present invention, various known additives, such as antioxidants, UV stabilizers, colorants, quenchers, deodorants, flame retardants, weathering agents, antistatic agents, mold release agents, and antioxidants, may be necessary. Inorganic fine particles, organic particles, and organic compounds can be added as the ion exchange agent, the coloring pigment, and the like.

After preparation of the polyalkylene glycol block copolymerized polylactide, the unreacted lactide is generally 10 mol% or less, but if not removed, the polyalkylene glycol block copolymerized polylactide in TiDy is extruded at Irritating lactide gas is produced. The content of unreacted lactide is preferably 8 mol% or less, more preferably 5 mol% or less.

The method for removing the unreacted lactide remaining in the polyalkylene glycol block copolymerized polylactide of the present invention is to chip the polyalkylene glycol block copolymerized polylactide, and then vacuum at a temperature of 40 ° C. or higher for 3 hours or more in a vacuum state. There is a method of drying, or when extruding the polyalkylene glycol block copolymerized polylactide using an extruder with a vacuum vent, it is possible to remove the unreacted lactide through the vacuum vent.

When the block copolymerized polylactide of the present invention was made into a film and tested for unreacted polyalkylene glycol, it was found that unreacted polyalkylene glycol did not leak. In addition, it was found that the flexibility is very excellent when made into a film. The general polylactide film is noisy when making a packaging film due to lack of flexibility, but the film made of the block copolymerized polylactide of the high molecular weight polyalkylene glycol and lactide of the present invention has excellent flexibility.

The flexibility of the block copolymerized polylactide of the polyalkylene glycol and lactide of the present invention was evaluated by the elastic modulus of the film. The lower the elastic modulus of the film, the better the flexibility. It is preferable that the elastic modulus with respect to the film of the block copolymerization polylactide of the polyalkylene glycol and lactide of this invention shall be 250 kgf / mm <^2> or less. When the modulus of elasticity exceeds 250 kgf / mm ² , it is loud and loud.

The present invention therefore encompasses moldings made of block copolymerized polylactides of high molecular weight polyalkylene glycols and lactide.

The present invention also encompasses films made of block copolymerized polylactides of high molecular weight polyalkylene glycols and lactide.

Thus, the resin produced according to the present invention is excellent in flexibility, extrudability, handleability and processability is improved, and when applied to the product, there is no bleeding noise and there is no outflow of unreacted polyalkylene glycol, and thus it can be preferably applied to commercialization. have.

Hereinafter, the present invention will be described in detail with reference to Examples, but the present invention is not limited by Examples. In the examples below, molecular weight means number average molecular weight and the unit is dalton.

Preparation Examples 1-5: Preparation of polyalkylene glycol block copolymerized polylactide

After the copolymerization component was added as shown in Table 1, vacuum drying was performed while stirring the impeller at 80 ° C. for 1 hour.

After the completion of drying of the copolymerization components, L-lactide was added to the reaction tube in the state of nitrogen flowing in the state of flowing nitrogen, and then vacuum drying was further performed while stirring the impeller at 80 ° C. for 2 hours. .

After the completion of the L-lactide vacuum drying, the catalyst (tin octylate) was introduced into the reaction tube in an amount of nitrogen as indicated in Table 1, followed by a target reaction temperature at 80 ° C. while stirring the impeller (see Table 1). ) To the temperature.

When the reaction was carried out at the target reaction temperature, the torque (load) of the stirrer started to increase gradually over time. When the target molecular weight was reached, the reaction was completed and the chip was discharged. The chip names of each preparation example are shown in Table 1 below.

Example 1 Preparation of Block Copolymerized Polylactide of High Molecular Weight Polyalkylene Glycol and Lactide

When polymerizing the polyethylene glycol block copolymerized polaractide as in Preparation Example 1, when the load of the impeller reached the equilibrium state where the load of the impeller reached the highest level, the chain extender ADR4368CS was 2% by weight relative to the total amount of the reactants. While loading and stirring again, it was confirmed that the load of the impeller went up, and when the load no longer went up, the chip was discharged.

The molecular weight (Mn) of the discharged polyethylene glycol block copolymer chip was 100,000 Dalton, the color tone b value of 4, the unreacted lactide content was 3 mol%, the lactic acid content was 0.1 mol%.

Examples 2 to 5 Preparation of block copolymerized polylactide of high molecular weight polyalkylene glycol and lactide

A chip was prepared in the same manner as in Example 1 except that polyalkylene glycol and a chain extender were used as in Table 2 below.

Reference Examples 1 to 5

The polyalkylene glycol polylactide resin chipped in Examples 1 to 5 was melt-extruded sheet-molded with a single screw screw extruder at 180 to 210 ° C. to make a film of 300 μm, and then this was 3 times in the longitudinal direction at 80 ° C. and transversely. Stretched 4 times in the direction to make a film.

The film was tested by the unreacted polyalkylene glycol distillation test described above, and it was found that the unreacted polyalkylene glycol did not leak.

Comparative Example 1

The polymerization was carried out in the same manner as in Example 1 except for the reaction conditions described in Table 2, followed by film formation. Visual inspection of the film under fluorescent lamps revealed a large distribution of foreign substances such as gels.

Comparative Example 2

The polymerization was carried out in the same manner as in Preparation Example except for the reaction conditions described in Table 3 below.

Comparative Example 3

When the polymerization reaction was carried out in the same manner as in Preparation Example except for the reaction conditions described in Table 3 below, the reaction time was too long, the reaction was stopped at 3 hours and analyzed.

Comparative Example 4

Except for the reaction conditions described in Table 3, the polymerization was carried out in the same manner as in Preparation Example to form a chip, and when extruded at 200 ° C. as it was, there was a lot of toxic gas generation from TiDy.

Comparative Examples 5-7

The polymerization was carried out in the same manner as in Preparation Example except for the reaction conditions described in Table 3 below.

Comparative Example 8

A lactide raw material having a content of 0.49 mol% of lactic acid in the lactide used for the block copolymerization experiment of polyalkylene glycol / polylactide was polymerized in the same manner as in Example 1, but the reaction did not proceed.

Experimental Example

Evaluation method for the target material prepared in the preparation examples, examples and reference examples was carried out as follows to evaluate the physical properties and the results are shown in Table 1-4.

(1) Quantitative Analysis of Unreacted Lactide and Lactic Acid in Polyalkylene Glycol Polylactide Resin

After dissolving an appropriate amount of polyalkylene glycol polylactide resin in CDCl ₃ and measuring by nuclear magnetic resonance (NMR), the proton peak of polylactide (5.17 ppm, 5.20 ppm) and the lactide CH proton peak (5.08) ppm, 5.11 ppm), and the proton peak (4.47 ppm, 4.49 ppm) of CH of lactic acid. The position of the peak may move little by little depending on the content of each component in the polymer and the measurement conditions, but anyone who understands the nuclear magnetic resonance method can predict the exact position with the area ratio. In the quantitative analysis of each component, the content of unreacted lactide and lactic acid were quantified using the area ratio, and the content of unreacted lactide and lactic acid was expressed in mol%.

(2) molecular weight measurement method

The polyalkylene glycol polylactide resin was dissolved in tetrahydrofuran (THF) and then measured by gel permeation chromatography (GPC). The data obtained by gel permeation chromatography have various items such as Mn, Mw, and Mp. In this experiment, molecular weight was measured based on Mn (number average molecular weight) (unit: dalton).

(3) elastic modulus measurement method

It measured according to ASTM D882.

(4) hue b value

The chip of the polyalkylene glycol / polylactide block copolymer was measured for the L value and the b value of the hunter using a color difference meter.

(5) metal element analysis

The content of metal elements was analyzed by ICP method.

(6) Lactic Acid Assay in Lactide

After the appropriate amount of lactide was dissolved in CDCl ₃ and measured by nuclear magnetic resonance (NMR), the hydrogen (H) of the CH bond of the lactide appeared at 5.0 to 5.2 ppm and the hydrogen (H) of the CH bond of the lactic acid was 4.4 to 4.5 ppm. By calculating the area ratio of these peaks, the content of lactic acid in the lactide was quantitatively expressed in mol% (mol%).

(7) Experiment of Leaching Unreacted Polyalkylene Glycol

When one film sample was left in a hot air oven at 100 ° C. for 2 hours, it was determined that unreacted polyalkylene glycol did not spill when no foreign matter was present on the surface of the film. It was determined that the alkylchelen glycol leaked.

division Chip Name Lactide
input
(kg) Copolymerization monomer Catalyst content
(wt%) reaction
Temperature
(℃) Number average
Molecular Weight
(Mn)
Hue b value Unreacted Lactate
content
(mol%) Lactic acid content
(mol%) Kinds Input (kg) input
(wt%) Production Example 1 T1 10 P-2 4.3 30 0.057 170 5.2 million 5 One 0.1 Production Example 2 T2 10 P-6 2.5 20 0.057 170 7.2 million 5 2 0.1 Production Example 3 T3 10 P-2 6.7 40 0.057 170 4 only 5 2 0 Production Example 4 T4 10 P-2 15.0 60 0.057 170 2.6 million 6 3 0 Production Example 5 T5 10 P-2 23.3 70 0.057 170 2.3 million 6 4 0.1

division Copolymerized polylactide Polyalkylene glycol content
(weight%) Chain extender
Kinds Chain extender
Mixing ratio
(weight%) Number average
Self weight (Mn)
Elastic modulus
(kgf / mm ² ) MD TD Example 1 T1 30 ADR4368CS 2 100,000 95 101 Example 2 T2 20 LA-1 2 100,000 110 123 Example 3 T3 40 ADR4368CS 3 9.5 million 80 96 Example 4 T4 60 ADR4368CS 3 9 million 72 83 Example 5 T5 70 ADR4368CS 3 8.7 million 50 75 Comparative Example 1 T1 30 ADR4368CS 8 130,000 97 103

division Lactide Dosage
(kg) Copolymerization monomer Catalyst content
(weight%) Reaction temperature
(℃) Number average
Molecular Weight
(Mn)
Hue b value Unreacted Lactide Content
(mol%) Lactic acid content
(mol%) Kinds Input (kg) Input amount (% by weight) Comparative Example 2 10 P-3 0.53 5 0.057 170 0.7 million Not measurable 83 2 Comparative Example 3 10 P-2 0.53 5 0.004 170 1.5 million 5 20 One Comparative Example 4 10 P-2 0.53 5 0.2 170 100,000 8 3 0.9 Comparative Example 5 10 P-2 10 50 0.057 170 1 million 5 23 2 Comparative Example 6 10 P-2 2.5 20 0.057 140 0.5 million Not measurable 30 3 Comparative Example 7 10 P-2 2.5 20 0.057 200 4.5 million 12 2 4

The types of copolymerization monomers of Tables 1 and 3 are shown in Table 4 below.

Copolymerized monomer type Chemical name manufacturer Na content
(ppm) Molecular Weight
(Present company) P-1 PEG8000 Polyethylene glycol SFC 31 8000 P-2 PEG20000 Polyethylene glycol Sanyokasei 17 20000 P-3 PEG20000 Polyethylene glycol Wuhan Xinlong 138 20000 P-6 NEWPOL PE-128 Polyoxyethylene Polyoxypropylene Glycol Sanyokasei 30 20000

Claims (18)

A block copolymerized polylactide of a high molecular weight polyalkylene glycol and lactide containing a chain extender and a polyalkylene glycol block copolymerized polyalkylide having a number average molecular weight of 80,000 to 500,000 daltons.
The method of claim 1, wherein the polyalkylene glycol is selected from polyethylene glycol, polyalkylene glycol, polypropylene glycol, polyoxyethylene polyoxypropylene glycol (polyoxyethylene polyoxypropylene block polymer) and polytetramethylene ether glycol Block copolymerized polylactide.
The block copolymer polylactide of claim 1, wherein the polyalkylene glycol has a number average molecular weight of 2000 dalton or more.
The block copolymer polylactide of claim 1, wherein the polyalkylene glycol has a sodium ion content of 130 ppm or less.
Preparation of block copolymerized polylactide of high molecular weight polyalkylene glycol and lactide, including first prepolymerization of polyalkylene glycol and lactide, and secondary polymerization by adding chain extender thereto Way.
The method according to claim 5, wherein in the second polymerization step, the chain extender is directly added to the polymerization reactor to perform the second polymerization.
The method according to claim 5, wherein after the first pre-polymerization step to produce a chip, in the process of extruding again in the second polymerization step, a chain extender is added to increase the molecular weight.
The method of claim 5, wherein the polyalkylene glycol is selected from polyethylene glycol, polyalkylene glycol, polypropylene glycol, polyoxyethylene polyoxypropylene glycol (polyoxyethylene polyoxypropylene block polymer) and polytetramethylene ether glycol Manufacturing method characterized in that.
The production method according to claim 5, wherein the polyalkylene glycol has a number average molecular weight of 2000 dalton or more and a sodium ion content of 130 ppm or less.
The preparation method according to claim 5, wherein the amount of polyalkylene glycol is 5 wt% or more and 80 wt% or less based on the sum of all raw materials added to the reaction.
The method of claim 5, wherein the lactide has a content of lactic acid of 0.40 mol% or less.
The method according to claim 5, wherein in the first prepolymerization step, the raw material is dried at a melting point (95 ° C.) or less, but dried to dry the moisture content to 500 ppm or less.
The method according to claim 5, wherein after the first prepolymerization step, the chain extender is mixed at 5 wt% or less with respect to the entire mixture.
The method according to claim 5, wherein the catalyst is used in an amount of 0.005% by weight or more and 0.2% by weight or less based on the total copolymerized polylactide.
The method according to claim 5, wherein the chain extender is at least one selected from epoxy, carbodiimide, oxazoline, caprolactam and isocyanate.
Molded article made of any one block copolymerized polylactide selected from claim 1 to claim 4.
Film made of any one block copolymerized polylactide selected from claim 1 to claim 4.
The film of claim 17 wherein the modulus of elasticity is 250 kgf / mm ² or less.