KR101543567B1

KR101543567B1 - method of manufacturing the oxo-biodegradable polymer master-batch

Info

Publication number: KR101543567B1
Application number: KR1020140016254A
Authority: KR
Inventors: 유재균
Original assignee: 유재균
Priority date: 2014-02-12
Filing date: 2014-02-12
Publication date: 2015-08-11

Abstract

The present invention relates to a method for preparing an oxide biodegradable resin master batch capable of improve the moldability of a molded article using a biodegradable resin and accelerating the oxidation and biodegradation processes. A master batch includes polyolefins, biodegradable agent, biodegradation agent, commercializing agent, and decomposition accelerating agent. The biodegradation agent includes metal salt of a carboxylic acid which uses the metal other than rare earth metals and a lubricant. When the master batch is prepared by using an extruder, the biodegradation agent and the decomposition accelerating agent are added through the rear end of the extruder. The present invention maintains the performance of the biodegradation agent and the decomposition accelerating agent without degrading the biodegradation agent and the decomposition accelerating agent in the master bath preparation process, thereby enabling excellent decomposition in the final molded article with adding only a small amount of the oxide biodegradable resin master batch. Accordingly, the present invention is economic and is capable of maintaining the strength of the final molded article while the final molded article is used through enabling the biodegradation process to begin after a predetermined time.

Description

[0001] The present invention relates to a method of manufacturing an oxidized biodegradable polymer master batch,

The present invention relates to a method for producing an oxidative biodegradable resin masterbatch which is added at the time of producing an oxidative biodegradable resin molded article and has excellent molding processability and can promote oxidative biodegradation.

BACKGROUND OF THE INVENTION [0002] Resin molded articles molded from petroleum resins such as polyethylene, polypropylene and polystyrene are used in various fields such as packaging films, textile products, electronic products, and industrial materials.

For example, when the resin molded article is incinerated, toxic gas may be generated, and since the petroleum resin shows hydrolysis resistance, it is not biodegraded in the ground when the resin molded article is disposed of in landfill or mountainous area, .

In order to solve the above problems, hydrolyzable biodegradable resins such as polylactic acid, modified starch, aliphatic polyester and the like have attracted attention as substitutes for petroleum resins.

Such a biodegradable resin is recognized as an eco-friendly material that does not destroy the natural environment because it is decomposed by microorganisms by being hydrolyzed by hydrolysis when being buried or disposal in mountainous area.

However, the biodegradable resin is difficult to be molded and processed compared with petroleum resin, and polylactic acid has a very poor rigidity and flexibility, which makes it difficult to apply to products such as packaging. Modified starch is excellent in economy, And the aliphatic polyester is insufficiently flexible. In addition, when the film is formed into a film, the tear strength and elongation are reduced. When applied as a packaging material, the heat seal property is deteriorated.

Generally, to improve the moldability and physical properties, a resin master batch containing a high concentration of decomposable components is prepared, and the resulting degradable resin master batch and molding resin are subjected to injection molding, extrusion molding, blow molding, cast molding a method of making a resin molded article by a method such as molding is used.

However, when the decomposable resin master batch is added to the molding resin and used, different kinds of resins are mixed, so that uniform mixing and dispersion are not easy, and different flow properties are exhibited, resulting in a problem of deteriorated molding processability.

In addition, in the case of an injection molded article having a thicker thickness than that of a thin film or sheet, the decomposition rate is very low and the content of the degradable master batch is increased, resulting in an uneconomical and inferior property of the molded article .

Korean Patent Laid-Open Publication No. 2001-0037124 describes a photodegradable and biodegradable masterbatch as "a photodegradable and biodegradable masterbatch chip, a method for producing the same, and a resin composition thereof" The invention provides a degradable masterbatch composed of a polycaprolactone or aliphatic polyester in which a photosensitive group is present in the polymer chain, but the moldability and moldability when the degradable masterbatch is molded with other resins There is no description of improvement in degradability of a thick molded article such as a molded article.

Disclosure of the Invention The present invention aims at solving the above problems, and an object of the present invention is to provide a method for producing an oxidative biodegradable resin masterbatch which exhibits an excellent oxidative biodegradation effect even when the molding processability is not lowered during the resin molding process.

In order to solve the above problems, the present invention provides a biodegradable biodegradable composition comprising 60 to 80% by weight of a polyolefin, 10 to 30% by weight of an oxidative biodegradation agent, 1 to 20% by weight of a compatibilizer, and 5 to 20% by weight of a degradation accelerator, A biodegradable resin masterbatch composition comprising 50 to 70% by weight of a carboxylic acid metal salt, 10 to 20% by weight of a carboxylic acid metal salt of a rare earth metal, and 10 to 20% by weight of a lubricant.

The present invention also relates to a process for producing a polyolefin composition, which comprises feeding a polyolefin and a compatibilizing agent to the tip of a screw extruder, melt mixing the polyolefin and a compatibilizing agent at an extrusion temperature of 140 to 170 ° C, and mixing the biodegradable and non- A method for producing a biodegradable resin masterbatch is provided.

The molded article molded using the oxidative biodegradable resin masterbatch produced by the production method of the present invention can be easily oxidized and decomposed by heat, light, moisture, etc. in a natural environment.

The oxidative biodegradable resin masterbatch produced by the production method of the present invention is added to a molding resin such as polyolefin, polyester, polystyrene and the like, and when it is molded by a molding method such as injection molding, extrusion molding, hollow molding, It is easy to melt-mix with the molding resin and the flowability is improved, and the molding processability is improved.

According to the present invention, since the oxidative biodegradable agent does not deteriorate during the master batch production and maintains its performance, the oxidative biodegradable resin masterbatch of the present invention can be decomposed at least in an excellent amount, so that it is economical. Or oxidized and decomposed by moisture, so that the strength can be maintained for a certain period of time.

The oxidative biodegradable resin masterbatch produced by the present invention comprises a polyolefin, a biodegradable oxidizer, a compatibilizer, and a degradation promoter.

Since the polyolefin constituting the oxidative biodegradable resin masterbatch of the present invention is polyethylene or polypropylene and is melted at a lower temperature than the synthetic resin having a different melting point, the degradation due to the deterioration of the oxidative biodegradable agent in the kneading process for producing the master batch And it is good in compatibility with other molding synthetic resins capable of forming resin molded articles.

It is preferable that the polyolefin is contained in an amount of 60 to 80% by weight in the oxidative biodegradable resin master batch, because it forms a pellet by acting as a binder of the oxidative biodegradable resin master batch composition.

At this time, the polyolefin preferably has a melt index of 1 to 20 g / 10 min (190 DEG C, 2.16 Kg) because it is excellent in flowability and kneadability in the master batch production and can maintain the mechanical strength in the final molded product.

The oxidative biodegradation agent constituting the oxidative biodegradable resin masterbatch of the present invention comprises 50 to 70% by weight of a carboxylic acid metal salt, 10 to 20% by weight of a carboxylic acid metal salt of a rare earth metal and 10 to 20% by weight of a lubricant.

At this time, the metal included in the carboxylic acid metal salt constituting the oxidative biodegradation agent may be selected from iron, copper, manganese, cobalt, vanadium, zinc, chromium, titanium, nickel and the like, and the metal is included in the rare earth carboxylic acid metal salt The metal may be selected from cerium and scandium, and the carboxylic acid may be selected from multivalent fatty acids such as stearic acid, oleic acid, erucic acid, linoleic acid, and the like.

The decomposition action of the polymer resin by the oxidative biodegradation agent will be described below.

In general, radicals are generated by a small amount of peroxide present on the surface of the polymer and oxygen in the air. Usually, such radicals are absorbed by the antioxidant in the polymer.

However, the transition metal contained in the carboxylic acid metal salt of the oxidative biodegradation agent used in the present invention is an oxidizing agent that oxidizes peroxides and redox reactions repeatedly to produce an autooxidative action of repeatedly generating radicals, The radical reaction starts with energy.

This reaction causes the carbon chain of the polymer to be cleaved and oxidative decomposition to occur, so that the molecular weight of the polymer is reduced. Such low molecular weight oxidized low molecular weight substances are, for example, carboxylic acids, ketones, alcohols and the like. Finally, the oxidized low molecular weight substances are digested and absorbed by microorganisms in the natural environment and decomposed into water, carbon dioxide or biomass, Can be completed.

The oxidative biodegradation agent to be used in the present invention is preferably two or more kinds including a carboxylic acid metal salt and a metal salt of a carboxylic acid metal salt, which is a rare earth metal, because the oxidative biodegradation agent can strongly oxidize.

When the oxidative biodegradation agent used in the present invention is added in a small amount of 0.1 to 5.0% by weight to a polyolefin resin (polyethylene, polypropylene) difficult to be biodegraded, the oxidized biodegradable resin molded article .

In order to add the oxidative biodegradation agent to the polyolefin resin in a small amount as described above, the master batch containing the oxidative biodegradation agent may be added to the polyolefin resin first.

In the oxidative biodegradable resin master batch of the present invention, the content of the oxidative biodegradable agent may be 10 to 30% by weight.

If the content is less than 10% by weight, the amount added to the molding resin for producing the molded article becomes large, which may lower the physical properties of the molding resin and is similar to the case of directly introducing the oxidative biodegradation agent, If it exceeds 30% by weight, agglomeration of the oxidative biodegradation agent may occur during the master batch production process described later, which is not preferable.

The oxidative biodegradation agent used in the present invention accelerates the oxidation of the polyolefin resin by using light, heat, oxygen and moisture as reaction energy.

An example of the oxidative biodegradation agent of the present invention is "P-Life" (Pacific Enterprise Japan Ltd.).

The compatibilizer constituting the oxidative biodegradable resin master batch of the present invention is an ethylene-vinyl acetate copolymer, and the ethylene-vinyl acetate copolymer is a polyolefin such as polyethylene, polypropylene, polybutene and the like having excellent affinity with the oxidative biodegradable agent The polyolefin and the oxidative biodegradation agent can be prevented from being phase-separated due to the difference in chemical structure, polarity and interfacial tension, and the oxidative biodegradation agent can be sufficiently mixed and degraded or thermally decomposed in a short period of time And prevents the oxidative biodegradation agent from being activated by heat during the extrusion process.

When the oxidized biodegradable resin masterbatch of the present invention is added to the resin for producing a molded article, the masterbatch first melts in the molding process and flows through the molding resin such as polyolefin, polyester, polystyrene, etc., It is possible to provide a homogeneous composition by improving the properties and to provide a stable structure in the final molded product so that an extruded molded article can provide a smooth and uniform surface free from roughness and gel on the surface even when containing additives.

In addition, the hydrolyzability is increased in the finally applied molded article because of its hydrophilicity, so that the decomposition of the molded article can be promoted.

The compatibilizing agent is preferably contained in an amount of 1 to 20% by weight in the oxidative biodegradable resin masterbatch. When the amount of the compatibilizing agent is less than 1% by weight, the affinity of the polyolefin with the oxidative biodegradable agent is lowered, If it exceeds 20% by weight, the affinity with the oxidative biodegradation agent becomes strong, which may interfere with the dispersion of the oxidative biodegradable agent, and tackiness and stickiness may appear, which is not preferable.

The ethylene-vinyl acetate copolymer preferably has a melt index of 1 to 20 g / 10 min (190 DEG C, 2.16 Kg) and a content of vinyl acetate of 30% or less because it can increase binding force with the polyolefin and the oxidative biodegradation agent.

The decomposition accelerator forming the oxidative biodegradable resin masterbatch of the present invention is used together with the oxidative biodegradable agent to accelerate the decomposition of the oxidative biodegradable resin molded article. As the chloride, potassium chloride, sodium chloride, lithium chloride, magnesium chloride, calcium chloride , Aluminum chloride, copper chloride, iron chloride and zinc chloride.

At this time, the resin forming the resin molded article may be oxidized and decomposed by acting with the oxidative biodegradation agent, even if it is a polyolefin which is hardly hydrolyzed or polyester or polystyrene.

In addition, the shape of the molded article can be decomposed in any of film, sheet, fiber, and block.

The decomposition accelerator is preferably contained in an amount of 5 to 20% by weight in the oxidative biodegradable resin master batch of the present invention. When the biodegradable resin master kneaded product is less than 5% by weight, promotion of decomposition with the oxidative biodegradable agent is not expected If it is more than 20% by weight, the physical properties and storage stability of the masterbatch and the final resin molded article may deteriorate and the decomposition may become too fast, which is not preferable.

Hereinafter, the production method of the oxidative biodegradable resin master batch of the present invention will be described.

In the production of the oxidative biodegradable resin masterbatch, a twin-screw extruder capable of extruding at a low screw speed and having a large and stable constant extrusion, excellent kneading effect, and extrusion at low temperature can be used.

The polyolefin and the compatibilizing agent are introduced into the tip of the twin-screw extruder and melt-mixed at an extrusion temperature of 140 to 170 ° C. The oxidative biodegradation agent and the decomposition promoter are fed at a relatively low temperature to the rear feeder To prepare an oxidative biodegradable resin master batch.

At this time, it is preferable that the side feeding position is a point of 3/4 to 4/5 from the tip of the extruder toward the die. If the point is less than 3/4, the oxidative biodegradation agent increases in residence time in the extruder The stability may deteriorate and the function may be deteriorated. If it is 4/5 or more, mixing and dispersion are insufficient, which is not preferable.

The oxidative biodegradable resin masterbatch prepared in this way is cooled, dehydrated, pelletized and dried, and packaged and packaged in aluminum-coated or laminated packaging material, so that the oxidative biodegradable agent used in the present invention can be maintained in a stable state.

Hereinafter, the present invention will be described in detail with reference to Examples. It is to be understood, however, that these examples are for illustrative purposes only and are not to be construed as limiting the scope of the invention as defined by the appended claims. And will be apparent to those skilled in the art to which the present invention pertains.

[Examples 1 to 6]

In the oxidative biodegradable resin master batch, the polyethylene and the ethylene-vinyl acetate copolymer were fed at the tip of a twin-screw extruder so as to be polyethylene and ethylene-vinyl acetate copolymer as a polyolefin and a compatibilizer as shown in the following Table 1, Lt; / RTI >

In the oxidative biodegradable resin master batch, the oxidative biodegradation agent and the decomposition promoter were put in the rear end 3/4 of the twin screw extruder so that the oxidative biodegradation agent and the decomposition promoter were as shown in Table 1 below, , Dehydrated, pelletized and dried to prepare an oxidative biodegradable resin master batch.

[Comparative Examples 1 to 6]

In the oxidative biodegradable resin master batch, polyethylene and ethylene-vinyl acetate copolymer were fed at the tip of a twin-screw extruder so that polyethylene and ethylene-vinyl acetate copolymer as a polyolefin and a compatibilizer were as shown in the following Table 2, Lt; / RTI >

In the oxidative biodegradable resin master batch, the oxidative biodegradation agent and the decomposition promoter were put in the rear end 3/4 of the twin screw extruder so that the oxidative biodegradation agent and the decomposition promoter were as shown in Table 2 below, , Dehydrated, pelletized and dried to prepare an oxidative biodegradable resin master batch.

(Unit: wt%) Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Polyolefin PE 65 53 75 55 55 65 Compatibilizer EVA 10 12 10 20 10 10 Oxidative biodegradation agent P-LIfe SMC2360 20 30 10 20 20 20 Decomposition accelerator
Potassium chloride 5 5 5 5 15 Sodium chloride 5 1) PE: low density polyethylene (5321, Hanwha Chemical, MI: 3)
2) EVA: Ethylene-vinyl acetate copolymer (E220F, Samsung Total, MI: 3)
3) P-LIfe SMC2360: oxidative biodegradation (Pacific Enterprise Japan Ltd., Japan)

(Unit: wt%) Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Polyolefin PE 70 53 80 53 67 48 Compatibilizer EVA 0 22 10 10 10 10 Oxidative biodegradation agent P-LIfe SMC2360 25 20 5 32 20 20 Decomposition accelerator Potassium chloride 5 5 5 5 3 22 ) PE: Low density polyethylene (5321, Hanwha Chemical, MI: 3)
2) EVA: Ethylene-vinyl acetate copolymer (E220F, Samsung Total, MI: 3)
3) P-LIfe SMC2360: oxidative biodegradation (Pacific Enterprise Japan Ltd., Japan)

[Application Test Example 1]

5 parts by weight of the oxidative biodegradable resin master batch of the above Examples and Comparative Examples and 100 parts by weight of linear low density polyethylene (FU149M, SK General Chemicals) were dry mixed and a film having a thickness of 15 mu m was prepared using an inflation film molding machine.

The properties of the film thus prepared were evaluated by the following test methods and the results are shown in Table 3

(1) Evaluation of degradability

a. Thermal aging test: According to ASTM D882-10 method, the elongation at break is measured by exposure to heat at 80 ° C for 1 to 10 days.

b. Ultraviolet light decomposability: The ultraviolet light is irradiated for 1 to 12 days according to the ASTM G154 method, and the elongation is measured.

c. Outdoor exposure degradability: Measure the state of the film visually after 100 days outdoors.

(2) Moldability evaluation

When the dry mixed mixture is uniformly discharged from the die of the film forming machine to form a uniform thickness and appearance, the film is observed visually, and when the surface of the film has a recessed or protruded portion and no thickness unevenness, X.

use
Oxidative biodegradable resin master batch Heat aging test
(Transverse elongation at break, unit%) Ultraviolet light decomposability
(Elongation in the longitudinal direction, unit%) outdoor
expose
Degradability film
Molding
Processability film
Molding
Immediately 6 days
lapse 8 days
lapse 10 days
lapse film
Molding
Immediately 4 days
lapse 8 days
lapse 12th
lapse 100 days
lapse Example 1 686 466 75 34 510 328 35 7 sliver
Occur ○ Example 2 659 412 64 33 490 298 31 7 sliver
Occur ○ Example 3 694 479 65 35 518 351 37 7 sliver
Occur ○ Example 4 687 467 74 34 513 331 35 8 sliver
Occur ○ Example 5 672 379 53 32 502 278 32 6 sliver
Occur ○ Example 6 680 462 74 34 508 326 36 8 sliver
Occur ○ Comparative Example 1 684 465 78 41 511 329 35 7 sliver
Occur × Comparative Example 2 653 468 76 43 488 336 34 6 sliver
Occur × Comparative Example 3 690 540 362 116 515 394 185 75 A little torn ○ Comparative Example 4 655 396 77 43 489 306 29 6 sliver
Occur × Comparative Example 5 680 483 179 84 508 345 66 17 sliver
Occur ○ Comparative Example 6 651 454 68 32 486 303 28 6 sliver
Occur × Control 766 685 664 678 525 515 482 421 circle
maintain ○ Control: linear low density polyethylene film (thickness: 15 mu m)

In Table 3, it can be seen that the film produced in the examples showed a sharp decrease in elongation as compared with the control, and the film was oxidized and decomposed as time elapsed due to exposure to heat, ultraviolet ray or field.

On the other hand, it can be seen from the comparative example 3 that when the content of the oxidative biodegradation agent is small, the degradation rate is lowered as compared with the examples, It can be seen that simultaneous use of the oxidative biodegradation agent and the decomposition promoting agent is required since it can be seen that the decomposition rate also decreases when the content of the promoter is small.

[Application Test Example 2]

2 parts by weight of the oxidative biodegradable resin master batch of the above Examples and Comparative Examples and 100 parts by weight of high density polyethylene (2520, SK General Chemicals) were dry-mixed and kneaded at a cylinder temperature of 220 캜 and a screw speed of 30 rpm To form a hollow container.

The dry blended mixture was uniformly discharged from the die of the blow molding machine to form a uniform thickness and appearance, and it was visually observed whether continuous molding was possible. There was no surface depressed or protruded on the outer surface of the hollow molded product, If not, it is evaluated as "O", otherwise, it is evaluated as "X".

[Application Test Example 3]

2 parts by weight of the oxidative biodegradable resin master batch of the above Examples and Comparative Examples and 100 parts by weight of impact polypropylene (B360F, SK General Chemicals) were dry-mixed and melt-kneaded in an injection molding machine at a melt temperature of 220 캜, A specimen with a thickness of 2 mm was molded.

In the outer appearance of the molded product injection-molded from the dry mixed mixture, the surface was evaluated as "O" when no depressed or protruded portion was present and no deformation was observed, and "X" was evaluated.

Use oxidized biodegradable resin
Master batch Blow molding processability Injection molding processability Example 1 ○ ○ Example 2 ○ ○ Example 3 ○ ○ Example 4 ○ ○ Example 5 ○ ○ Example 6 ○ ○ Comparative Example 1 × × Comparative Example 2 × × Comparative Example 3 ○ ○ Comparative Example 4 × × Comparative Example 5 ○ ○ Comparative Example 6 × ×

From Table 4, it can be confirmed that the mixture according to the example of the present invention is excellent in the blow molding processability and the injection molding processability.

From Comparative Examples 3 and 5, it can be seen that the molding processability is improved when the content of the oxidative biodegradation agent or decomposition promoter is low, but it is confirmed from the results of Table 3 that the degradation rate is lowered.

Claims

delete

Polyolefin and ethylene-vinyl acetate copolymer as a compatibilizing agent were put into the tip of a screw extruder and melt-mixed at an extrusion temperature of 140 to 170 ° C,
An oxidative biodegradation agent containing 50 to 70% by weight of a carboxylic acid metal salt in which the metal is a metal other than rare earth, 10 to 20% by weight of a carboxylic acid metal salt as a rare earth metal and 10 to 20% by weight of a lubricant and potassium chloride or sodium chloride as a decomposition accelerator, Side feeding at the rear end,
Wherein the mixture by mixing comprises 60 to 80% by weight of the polyolefin, 1 to 20% by weight of a compatibilizer, 10 to 30% by weight of an oxidative biodegradation agent and 5 to 20% by weight of a decomposition promoter. &Lt; / RTI >

6. The method of claim 5,
Wherein the side feeding position is 3/4 to 4/5 in the die direction from the tip of the screw extruder.

delete

6. The method of claim 5,
The metal contained in the carboxylic acid metal salt in which the metal is a metal other than rare earths is selected from the group consisting of iron, copper, manganese, cobalt, vanadium, zinc, chromium, titanium and nickel. Carboxylic acid is selected from the group consisting of stearic acid, , And linoleic acid. &Lt; RTI ID = 0.0 > 11. < / RTI >

6. The method of claim 5,
Wherein the ethylene-vinyl acetate copolymer has a melt index of 1 to 20 g / 10 min (190 DEG C, 2.16 Kg).