KR101334476B1

KR101334476B1 - Polylactic acid sol and method of manufacturing the polylactic acid sol

Info

Publication number: KR101334476B1
Application number: KR1020100024246A
Authority: KR
Inventors: 황승철; 김지영; 박귀봉; 강창원; 권준혁; 권현종; 박상선; 김장기; 이경민
Original assignee: (주)엘지하우시스
Priority date: 2010-03-18
Filing date: 2010-03-18
Publication date: 2013-11-29
Also published as: KR20110105144A

Abstract

Disclosed are a PLA (poly lactic acid) sol that can be used for wallpaper, automobile seat, leather, glass fiber impregnation, and the like, and a method of manufacturing the same.
PLA sol manufacturing method according to the present invention comprises the steps of preparing a PLA solution by adding PLA (poly lactic acid) to the volatile solvent; Adding a nonphthalate plasticizer to the PLA solution; And removing the volatile solvent contained in the PLA solution through drying.

Description

PLA sol and its manufacturing method and PLA sol manufactured through the same {POLYLACTIC ACID SOL AND METHOD OF MANUFACTURING THE POLYLACTIC ACID SOL}

The present invention relates to a PLA (polylactic acid) sol (sol) that can be used for wallpaper, car seat, leather, glass fiber impregnation, and more specifically, PLA that can easily form a PLA sol from pellets or powder form PLA It relates to a sol and a preparation method thereof.

PLA (polylactic acid) is generated from renewable plant resources, and because of its environmentally friendly properties, it is widely used in food container packaging materials.

In the case of PLA itself as a hard material, there is a problem that the impact resistance or tensile strength is weak.

Therefore, there is a need for a PLA sol capable of easily producing a PLA sheet while improving impact resistance or tensile strength so as to be applied to wallpaper, automobile sheet, leather, glass fiber impregnation, etc. in sheet form.

It is an object of the present invention to provide a PLA sol that can be used for wallpaper, car seat, leather, glass fiber impregnation and the like.

Another object of the present invention is to provide a method for easily preparing a PLA sol using a volatile solvent and a nonphthalate plasticizer or a nonphthalate plasticizer.

PLA sol manufacturing method according to an embodiment of the present invention for achieving the above object comprises the steps of preparing a PLA solution by adding PLA (poly lactic acid) to the volatile solvent; Adding a nonphthalate plasticizer to the PLA solution; And removing the volatile solvent contained in the PLA solution through drying.

PLA sol manufacturing method according to another embodiment of the present invention for achieving the above object is to form a sol by adding 5 to 100 parts by weight of a non-phthalate-based plasticizer to 100 parts by weight of PLA in a pellet or powder form. It is done.

PLA sol according to the present invention for achieving the above another object is characterized in that it is manufactured by the above methods for the use of wallpaper, car seat, leather (leather) or glass fiber impregnation.

The PLA sol preparation method according to the present invention has an advantage of easily forming a PLA sol using only a volatile solvent and a plasticizer or a plasticizer.

PLA sol prepared by the production method according to the present invention can be applied to a variety of uses, such as wallpaper, car seat, leather or glass fiber impregnation due to environmentally friendly properties.

1 is a flow chart schematically showing a PLA sol manufacturing method according to an embodiment of the present invention.

Advantages and features of the present invention and methods for achieving them will be apparent with reference to the embodiments described below in detail with the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but is capable of many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, with reference to the accompanying drawings it will be described in detail with respect to PLA sol and a method for producing the same.

Referring to Figure 1, PLA sol according to an embodiment of the present invention includes a PLA solution preparing step (S110), a plasticizer addition step (S120) and volatile solvent removal step (S130).

In the PLA solution preparation step (S110), PLA (poly lactic acid) is added to the volatile solvent to prepare a PLA solution.

Volatile solvents can be chloroform or methyl ethyl ketone.

In this case, the added PLA may be PLA in a pellet form or PLA in a powder form.

PLA is a thermoplastic polyester of lactide or lactic acid, and may be prepared by polymerizing lactic acid produced by fermenting starch extracted from renewable plant resources such as corn and potatoes.

This PLA is an eco-friendly properties, which in use or disposal process, the emission of environmentally harmful substances such as CO ₂ poly significantly less than the petroleum-based materials such as polyvinyl chloride (PVC), even at the time of disposal can be easily decomposed in the natural environment Have

PLA resin can be divided into crystalline PLA (c-PLA) and amorphous PLA (a-PLA). In this case, in the case of crystalline PLA, a bleeding phenomenon in which the plasticizer flows out of the sheet-like surface may occur, so it is preferable to use amorphous PLA. In the case of using amorphous PLA, there is an advantage that the compatibilizer, which is essentially added to prevent the bleeding phenomenon, is not added. In the case of using amorphous PLA, it is most preferable to use 100% amorphous PLA as PLA, and if necessary, PLA in which crystalline and amorphous coexist.

In the plasticizer addition step (S120), the plasticizer is added to the prepared PLA solution. The plasticizer softens hard PLA, and serves to secure moldability by supplementing impact resistance.

The plasticizer is preferably added in the range of 5 to 100 parts by weight or less based on 100 parts by weight of PLA. When the amount of the plasticizer is less than 5 parts by weight based on 100 parts by weight of PLA, the softening degree of PLA is low and it is difficult to supplement the impact resistance of PLA. In addition, when the amount of the plasticizer is more than 100 parts by weight compared to 100 parts by weight of PLA, the plasticizer may bleed out of the product (bleeding) may occur, it may hinder the transparency due to the whitening phenomenon.

On the other hand, the most commonly used plasticizer is a phthalate (phthalate) -based plasticizer, but this is undesirable because it may have a harmful effect on the human body due to toxicity. Therefore, in the present invention, a non-phthalate plasticizer is used as the plasticizer, which may be ATBC (acetyl tributyl citrate).

In the volatile solvent removal step (S130), the volatile solvent is removed from the PLA solution containing the plasticizer through drying. The drying temperature is not limited, but may preferably present a temperature higher than the boiling point of the volatile solvent.

When using chloroform as a solvent it can be presented as a drying temperature of approximately 65 ~ 90 ℃, if using methyl ethyl ketone as a solvent may be presented as a drying temperature of 80 ~ 110 ℃.

The prepared PLA sol is further added with one or more additives from 0.1 to 20 parts by weight of an acrylic copolymer, 0.01 to 10 parts by weight of higher fatty acids and up to 10 parts by weight of polycarbodiimide based on 100 parts by weight of PLA. Can be. These additives may be added after or before the PLA solution preparation step (S110), before or after the plasticizer addition step (S120).

Among the additives, the acrylic copolymer serves as a melt strength enhancer. PLA sol itself is not good melt strength or heat resistance because the acrylic copolymer to compensate for this point to ensure the strength when melt extrusion from the PLA sol in sheet form. In addition, the acrylic copolymer may be usefully applied not only to melt extrusion but also to calendaring, press processing, and the like from the PLA sol.

The acrylic copolymer is preferably added in a proportion of 0.1 to 20 parts by weight based on 100 parts by weight of PLA. When the content of the acrylic copolymer is less than 0.1 parts by weight, the improvement of the melt strength of the PLA is insufficient. If the content of the acrylic copolymer exceeds 20 parts by weight, the compatibility of other layers in the PLA sol may be due to compatibility problems with other materials. Overall physical properties may be reduced.

Higher fatty acids are lubricants, which prevent deposits and crosslinked products from accumulating in a calendering process using PLA sol or the like. In addition, advanced fatty acids lubricate the surface of metal equipment such as calender rollers during molding to improve fluidity, prevent adhesion between metal equipment and PLA resin, improve slip properties, adjust melt viscosity, and render molding It can be used to improve workability and the like.

Such higher fatty acids may be stearic acid, a saturated higher fatty acid having 18 carbon atoms.

The higher fatty acid is preferably added in 0.01 to 10 parts by weight based on 100 parts by weight of PLA. If the higher fatty acid is less than 0.01 parts by weight compared to 100 parts by weight of PLA, the effect of adding higher fatty acids may not be obtained. On the contrary, if the higher fatty acid exceeds 10 parts by weight, impact resistance, heat resistance, glossiness, etc. of PLA may be deteriorated.

The hydrolysis agent serves to impart the water resistance of the sheet produced from the PLA sol by inhibiting the hydrolysis reaction. Such a hydrolysis agent can be used without limitation so long as it is usually used as a hydrolysis agent such as carbodiimide, oxazoline, and the like.

The hydrolysis agent is preferably added in an amount ratio of 10 parts by weight or less based on 100 parts by weight of PLA. As the hydrolyzate is added in a large amount, the water resistance may be improved, but when the hydrolyzate is added in an amount of more than 10 parts by weight based on 100 parts by weight of PLA, the molding processability of the sheet formed from the PLA sol may be deteriorated.

1 shows an example using a volatile solvent, the PLA sol manufacturing method according to the present invention can be prepared directly by mixing the PLA and the plasticizer without passing through the volatile solvent.

In this case, preferably, 5 to 100 parts by weight of a nonphthalate-based plasticizer such as ATBC may be added to 100 parts by weight of PLA in pellet or powder form to form a sol.

Herein, one or more additives of the acrylic copolymer as the above-described melt strength modifier, the higher fatty acid as the lubricant, and the hydrolysis agent may be further added in the aforementioned content range.

The prepared PLA sol can be used for wallpaper, car seat, leather (leather) or glass fiber impregnation, etc., and can be applied to various other applications.

The PLA sol may be processed into a desired sheet-like molded body through a calendering process using an L-shaped four-roll roll calender and the like in a processing temperature range of about 120 to 200 ° C.

Manufacturing example

Below, the preferable manufacture example of this invention is described. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

Details that are not described herein will be omitted since the description can be inferred by those skilled in the art.

In Example 1, 100 g of amorphous PLA was added to 500 ml of chloroform and stirred, and then, 30 g of ATBC, 10 g of acrylic copolymer, 10 g of stearic acid, 5 g of stearic acid, and 3 g of carbodiimide were added to the prepared PLA solution as a plasticizer, followed by stirring. Prepared.

The prepared PLA sol was first kneaded using an extruder, kneaded at 140 ° C. with a half-barrier mixer, and then mixed first and second using a double roll of 140 ° C. Thereafter, the prepared raw material was calendered at a temperature of 130 ° C. to prepare a sheet sample having a thickness of about 0.5 mm.

The sheet sample was measured to be approximately 8.3 kgcm / cm impact strength measured by the ASTM D256 method, and also no bleeding and whitening. If the plasticizer is not added, the impact resistance of the PLA sheet is only about 1.2 kgcm / cm, the impact strength of the preparation is quite high.

On the other hand, the impact strength of Example 2 prepared in the same manner as in Example 1 except that the addition of ATBC 140g as a plasticizer to 100g of crystalline PLA was 8.7 kgcm / cm, but the bleeding phenomenon occurred on the sheet surface.

In addition, the impact strength of Example 3 prepared by the same method as Example 1 except that the addition of ATBC 20g as a plasticizer to 100g of crystalline PLA is about 4.3 kgcm / cm impact strength is relatively low compared to Example 1 And some bleeding occurred.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. . Accordingly, the true scope of the present invention should be determined by the following claims.

S110: PLA solution manufacturing step
S120: plasticizer addition step
S130: Volatile Solvent Drying Step

Claims

Preparing a PLA solution by adding amorphous PLA (poly lactic acid) to chloroform;
5 to 100 parts by weight of a nonphthalate plasticizer, 0.1 to 20 parts by weight of an acrylic copolymer as a melt strength modifier, 0.01 to 10 parts by weight of stearic acid as a lubricant, and 3 to 3 parts by weight of the PLA solution, based on 100 parts by weight of the amorphous PLA Adding 10 parts by weight; And
Removing chloroform contained in the PLA solution through drying;
PLA sol manufacturing method comprising a.

The method of claim 1,
The amorphous PLA is a PLA sol manufacturing method, characterized in that the amorphous PLA in the form of a pellet (pellet) or powder form.

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The method of claim 1,
The non-phthalate plasticizer is PLABC manufacturing method characterized in that the acetyl tributyl citrate (ATBC).

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100 parts by weight of amorphous PLA in pellet or powder form, 5 to 100 parts by weight of nonphthalate plasticizer, 0.1 to 20 parts by weight of acrylic copolymer as melt strength modifier, 0.01 to 10 parts by weight of stearic acid as lubricant and 3 to carbodiimide PLA sol production method characterized in that the addition of 10 parts by weight to form a sol.

9. The method of claim 8,
The non-phthalate plasticizer is PLA sol manufacturing method characterized in that the ATBC.

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