KR20000019010A - Polyester resin composition and preparation thereof - Google Patents

Abstract

PURPOSE: A biodegradable polyester resin composition is provided to have a high molecular weight, melting viscosity, and tear strength adequate for a practical use. CONSTITUTION: The composition comprises (1) an aliphatic (or cyclic aliphatic) dicarboxylic acid including succinic acid (or its anhydride), (2) an aliphatic (or cyclic aliphatic) glycol including at least one selected from the group consisting of 1,4-butanediol and ethyleneglycol, and (3) 0.1 to 30 wt.% of a monomer containing at least one functional group such as hydroxyl and amine groups. The molecular obtained by at least one reaction selected from condensation, esterification and ester exchange reaction, and poly condensation has an average molecular weight of 30,000 to 70,000, a weight average molecular weight of 160,000 to 600,000, a melting point of 61 to 120°C and a melt viscosity of 0.1 to 50 at 190°C for 2,160 grams. The glycol and the dicarboxylic acid are added at a mole ratio of 1: 1.1 to 2. The monomer includes at least one selected from the group consisting of 3-amino-1-propanol, 1-amino-2-propanol, 2-amino-1-butanol, 4-amino-1-butanol, 3-amino-2,2-dimethyl propanol, 6-amino-1-hexanol, 2-amino-1,3-propanediol, 2-amino-2-methyl-1,3-propanediol, 2,4-diamino-6-hydroxy-5-mercaptopyrimidine, 4,5-diamino-6-hydroxy-2-mercapto pyrimidine, 3,4-diamino-5-hydroxypyrazole sulphate, 2,4-diamino-6-hydroxy pyrimidine monohydrate, 4,6-diamino-2-hydroxy-1,3,5-trizine, 2-aminobenzyl alcohol, 3-aminobenzyl alcohol, 4-aminobenzyl alcohol, 2-amino phenol, 3-amino phenol, 4-amino phenol, 2-amino-4-methylphenol, 2-amino-5-methylphenol, 4-amino-3-methylphenol, 2-amino-4-nitrophenol, 2,4-diamino phenol-dihydro chloride, 2,6-dihydroxybenzamide, 3,5-dihydroxybenzamide, 3,5-dihydroxybenzamide, 2,4-dihydroxybenz hydrazide, 3,5-dihydroxybenzhydrazide, 3,5-dihydroxybenzhydrazide and mixtures thereof.

Description

Polyester resin composition and its manufacturing method

The present invention relates to a polyester resin composition and a method for manufacturing the same, and in particular, the conventional aliphatic polyester has a biodegradability and solves the difficulty of practical use as a trash bag or shopping bag caused by the lack of tear strength. A high molecular weight polyester resin composition and a method for producing the same.

Representative polyester resins used in various applications such as fibers, molded articles and films are high molecular weight aromatic polyester resins produced by condensation polymerization of terephthalic acid and ethylene glycol or terephthalic acid and 1,4-butanediol, wherein high molecular weight poly Ester refers to a polymer having a number average molecular weight of 10,000 or more. However, the aromatic polyester resins do not decompose in the natural ecosystem after disposal and have remained for a long time causing serious environmental pollution problems.

On the other hand, it is already known that aliphatic polyesters are biodegradable (see Journal of Macromol. SCI-Chem., A-23 (3), 1986, 393-409), and are currently used for medical materials, agricultural and fishing materials, and Some applications have been made in packaging materials, and other practical researches are being conducted.

However, due to the flexible structure and low crystallinity of the main chain, the existing aliphatic polyester has low melting point and low thermal stability during melting, which is easy to thermally decompose, and it is not easy to form processing due to the melt flow index, as well as tensile strength and tearing steel. There is a problem that the use is limited because of poor physical properties such as. In order to put the aliphatic polyester into practical use, the number average molecular weight must be raised to 30,000 or more, but it is difficult to raise the number average molecular weight of the aliphatic polyester to 15,000 or more in a commonly known condensation polymerization system.

As one method for solving this problem, a method of synthesizing a high molecular weight aliphatic polyester resin having a number average molecular weight of 30,000 or more by appropriately adjusting the reaction temperature, vacuum degree and catalyst conditions is disclosed in Korean Patent Application Laid-Open No. 95-758. It is disclosed in the call. However, the aliphatic polyester resin produced by this method has a low weight average molecular weight, is extremely sensitive to heat, and is poor in moldability.

As another conventional example, Korean Patent Laid-Open Publication No. 95-14171 discloses a method for producing a high molecular weight aliphatic polyester by adding a monomer of a trivalent or higher polyhydric alcohol or a trivalent or higher polyhydric carboxylic acid during polyester production. Is disclosed. According to this method, by introducing the monomer into the reaction system, the reaction time can be shortened, the molecular weight distribution can be diffused, and the moldability can be improved. However, since the low molecular weight polyester is rapidly increased to decrease the physical properties such as tensile strength, it is not only practical to use, but also has a problem of high gelation, which makes it difficult to control the reactivity.

Another method of raising the number average molecular weight of aliphatic polyester is disclosed in Korean Patent Application Laid-Open No. 95-25072, which refers to (1) aliphatic (including cyclic aliphatic) glycols, and (2) Presence or ratio of aliphatic (including cyclic aliphatic) dicarboxylic acids (or acid anhydrides) as a main component and a small amount of (3) trivalent or more polyhydric alcohols or trivalent or higher polyhydric carboxylic acid (or acid anhydrides) monomers The high molecular weight aliphatic polyester composition obtained by making the isocyanate which is a coupling agent react further with the aliphatic polyester of the number average molecular weight 15,000-20,000 obtained by dehydration reaction and deglycol reaction in presence is disclosed. The number average molecular weight of the aliphatic polyester resin obtained by this method was about 20,000-70,000. However, according to this method, since the reaction time is long, productivity decreases, and the isocyanate which is a coupling agent used to increase the molecular weight is extremely harmful to the human body.

As described above, in order to prepare a high molecular weight aliphatic polyester resin, a method of adding an isocyanate, which is a coupling agent, or a polyfunctional monomer such as a polyhydric alcohol or a polyhydric carboxylic acid is used to prepare an aliphatic polyester. come. However, the aliphatic polyester thus prepared had problems with productivity, physical properties, moldability, and the like.

It is an object of the present invention to provide a biodegradable polyester resin composition having a high molecular weight sufficient for practical use and a method for producing the same.

Another object of the present invention is to provide a polyester resin composition having mechanical properties such as melt viscosity required for various molding processes such as injection molding, blow molding, film molding, and the like, and sufficient tear strength required for practical use of the molded article, and a manufacturing method thereof. It is.

According to the present invention, (1) aliphatic (including cyclic aliphatic) dicarboxylic acid (or its anhydride) containing succinic acid, and (2) aliphatic containing any one or more selected from 1,4-butanediol and ethylene glycol ( Condensation reaction, esterification reaction, in the presence of a monomer having a glycol containing a cyclic aliphatic group) as a main component and each having one or two or more hydroxyl and amine groups as functional groups of 0.1 to 30% by weight relative to the theoretical weight of polyester. And there is provided a polyester resin composition obtained by a polycondensation reaction after any one or two or more reactions selected from the transesterification reaction.

In order to prevent the rapid increase and gelation of low molecular weight polyester during the preparation of the polyester resin, preferably, any one of condensation reaction, esterification reaction and transesterification reaction is performed by first adding the dicarboxylic acid and the monomer. After distilling out water or methanol, the resulting reaction product and the glycol are esterified or transesterified, followed by polycondensation reaction of the reaction product to produce a high molecular weight polyester resin. It is characterized by.

In more detail with respect to the polyester resin composition of the present invention, selected from aliphatic (including cyclic aliphatic) dicarboxylic acid (or anhydride thereof) containing succinic acid as the main component, 1,4-butanediol and ethylene glycol Aliphatic (including cyclic aliphatic) glycols containing any one or more thereof are used, and preferably (1) succinic acid single component; Ethylene glycol monocomponent or a mixed component of ethylene glycol and other glycols (glycol having an alkylene group having 3 to 10 carbon atoms (including cyclic alkylene group)), succinic acid monocomponent; 1,4-butanediol alone or a mixture of 1,4-butanediol and other glycols (glycols having 2 to 3, 4 to 10 alkylene groups (including cyclic alkylene groups)), succinic acid alone or succinic acid And a mixed component of other dicarboxylic acid (dicarboxylic acid having an alkylene group having 3 to 10 carbon atoms (including cyclic alkylene group)); Single component of ethylene glycol, (4) succinic acid single component or mixed component of succinic acid and other dicarboxylic acid (dicarboxylic acid having 3 to 10 alkylene groups (including cyclic alkylene groups)); A single component of butanediol, a succinic acid single component or a mixed component of succinic acid and other dicarboxylic acids (dicarboxylic acid having an alkylene group having 3 to 10 carbon atoms (including cyclic alkylene group)); Ethylene glycol single component or mixed component of ethylene glycol and other glycols (glycols having 3 to 10 alkylene groups (including cyclic alkylene groups)), (6) succinic acid single component or succinic acid and other dicarboxylic acids (carbon number A mixed component of an alkylene group having 3 to 10 (including a dicarboxylic acid having a cyclic alkylene group); Any one selected from 1,4-butanediol alone or a mixture of 1,4-butanediol and other glycols (glycols having 2 to 3, 4 to 10 alkylene groups (including cyclic alkylene groups)) is used. .

In addition, as the monomer added to the present invention, a monomer including one or two or more hydroxyl groups and amine groups, respectively, is used as a functional group, and as described above, one or more hydroxyl groups and amine groups are used as the functional group, and the benzene ring in the molecule thereof is included. Compounds containing an amide group in the molecule may be used, including one or more hydroxyl groups and amine groups, respectively, as the benzene derivative and the functional group containing. Examples of the monomer include 3-amino-1-propanol, 1-amino-2-propanol, 2-amino-1-butanol, 4-amino-1-butanol, 3-amino-2,2-dimethyl propanol, 6-amino -1-hexanol, 2-amino-1,3-propanediol, 2-amino-2-methyl-1,3-propanediol, 2,4-diamino-6-hydroxy-5-mercaptopyrimidine, 4,5-diamino-6 -hydroxy-2-mercapto pyrimidine, 3,4-diamino-5-hydroxypyrazole sulphate, 2,4-diamino-6-hydroxy pymidine monohydrate, 4,6-diamino-2-hydroxy-1,3,5-triazine, etc. As the benzene derivative, 2-aminobenzyl alcohol, 3-aminobenzyl alcohol, 4-aminobenzyl alcohol, 2-aminophenol, 3-aminophenol, 4-aminophenol, 2-amino-4-methylphenol, 2-amino-5-methylphenol, 4 -amino-3-methylphenol, 2-amino-4-nitrophenol, 2,4-diaminophenol-dihydrochloride, and the like, and the compound containing the amide group includes 2,6-dihydroxybenzamide, 3,5-dihydroxybenzamide, 2,4-dihydroxybenz hydrazide, 3,4-dihydroxybenzhydrazide, 3,5-dihydroxybenzhydrazide, and the like, and any one or two or more selected from these The compound is used as the monomer of the present invention.

In addition, according to the present invention is provided a method for producing the aliphatic polyester resin, the production method is composed of a three-step reaction, will be described below divided by step.

In a first step reaction for producing the polyester resin of the present invention, an aliphatic (including cyclic aliphatic) dicarboxylic acid (or anhydride thereof) containing succinic acid and one or more hydroxyl groups and one or more amine groups are respectively included as functional groups. The monomer is added to carry out any one or two or more reactions selected from condensation reaction, esterification reaction and transesterification reaction at a temperature of 160 to 240 ° C. to distill water, methanol or a small amount of acid. At this time, if the reaction temperature is less than 160 ℃ water or methanol is difficult to escape, whereas if it exceeds 240 ℃, the reaction products may be carbonized or scattered, so pay attention to the reaction temperature control. In addition, the addition amount of the monomer is preferably about 0.1 to 30% by weight relative to the theoretical weight of the polyester, if the addition amount is less than 0.1% by weight not only the reaction time is long, but also the physical properties are lowered, while the addition amount is 30% by weight Beyond this, the rate of biodegradation is delayed and the melting point is too high, causing problems in the molding process and increasing costs. The chemical reaction proceeding in this process is shown in Scheme 1 below, in which an example using 4-amino-1-butanol containing succinic acid as the dicarboxylic acid and one amine group and one hydroxyl group as the monomer is used. Indicated.

HOOC- (CH ₂ ) ₂ -COOH + HO- (CH ₂ ) ₄ -NH ₂ → H- [O (CH ₂ ) ₄ NHCO- (CH ₂ ) ₂ -CO] _n -OH + H ₂ O

or HO- [C: O- (CH ₂ ) ₂ -C: O- (CH ₂ ) ₄ -NH] _n -H + H ₂ O

or HO-C: O- (CH ₂ ) ₂ -C: OO- (CH ₂ ) ₄ -NH-C: O- (CH ₂ ) ₂ -C: O-OH + H ₂ O

However, in said Reaction Formula 1, n is 1-50 as an integer. Since the dicarboxylic acid component is more added than the monomer component, the dicarboxylic acid is bonded to the sock end of the reaction product, and the reaction produces a reaction product having a number average molecular weight of 200 to 10,000. Thereafter, the unreacted dicarboxylic acid component remains in the reaction system.

Next, in the second stage reaction, aliphatic (including cyclic aliphatic) glycol containing any one or more selected from 1,4-butanediol and ethylene glycol is added to the first stage reaction product at a temperature of 200 to 220 ° C. Esterification or transesterification is carried out to completely drain off the water or methanol produced. The chemical reaction proceeding in this process is shown in the following schemes 2 and 3, wherein the glycol is shown an example using 1,4-butanediol. In addition, Scheme 2 below shows a chemical reaction between the reaction product of Scheme 1 and aliphatic (including cyclic aliphatic) glycol, and Scheme 3 shows unreacted aliphatic (including cyclic aliphatic) remaining in the reaction system of the first stage reaction. The esterification reaction of a carboxylic acid (or anhydride thereof) with an aliphatic (including cyclic aliphatic) glycol is shown.

HOOC- (CH ₂ ) ₂ -C: O- [O- (CH ₂ ) ₄ NH-C: O- (CH ₂ ) ₂ -C: O-] _n -OH + HO- (CH ₂ ) ₄ -OH →

HO- [C: O- (CH ₂ ) ₂ -CO- (O (CH ₂ ) ₄ NHCO- (CH ₂ ) ₂ -CO) _n -O (CH ₂ ) ₄ -O] _n -H

HOOC- (CH ₂ ) ₂ -COOH + HO- (CH ₂ ) ₄ -OH → HO- [OC- (CH ₂ ) ₂ -COO- (CH ₂ ) ₄ O] _m -H

Reaction Schemes 2 and 3 show only representative examples of chemical reactions that proceed in the reaction system, n is 1 to 50 as an integer as in Scheme 1, and m is 180 to 400 as an integer.

At this time, the reaction molar ratio of the glycol and the dicarboxylic acid introduced in the first step ranges from 1: 1.1 to 1: 2. When the molar ratio is less than 1: 1.1, the reactivity decreases and affects color. On the other hand, exceeding 1: 2 is expensive. Therefore, it is preferable that the molar ratio of the said compound is 1: 1.4.

Lastly, in the third step reaction, the second step reaction product is polycondensed for 60 to 200 minutes at a temperature of 210 to 270 ° C. and a vacuum of 0.005 to 10 torr to produce a high molecular weight polyester. That is, the reaction product and the unreacted dicarboxylic acid component generated in the first step described above undergo chemical reactions as in Scheme 2 and Scheme 3, respectively, and are continuously discharged with water, methanol, or glycol. Reaction with adjacent molecules forms a polyester resin having a number average molecular weight of 30,000 to 70,000 and a weight average molecular weight of 160,000 to 600,000.

On the other hand, according to the present invention, the catalyst may be added at the beginning or the end of the esterification reaction or transesterification reaction of the second step, the addition amount is 0.02% to 2% by weight relative to the total composition weight. When the addition amount is less than 0.02% by weight, it is difficult to pour out the theoretical amount of water, methanol or glycol, and it takes a considerable time to pour out the theoretical amount of the water, methanol or glycol, while when the addition amount of the catalyst exceeds 2% by weight The theoretical amount of water, methanol or glycol is easily spilled but can affect color. In this case, as the catalyst used, any one or two or more mixed catalysts selected from metal compounds containing Ti, Ge, Zu, Fe, Mu, Co, Zr and the like is used. Preferably, titanate, antimonate, tin An organometallic compound containing an oxide is used, and more preferably selected from tetrabutyl titanate, calcium acetate, antimony oxide, dibutyl tin oxide, zinc acetate, antimonia acetate, antimony glycolate, and tetrapropyl titanate Either one or more mixed catalysts are used.

In addition, the stabilizer may be added at the beginning or the end of the second esterification reaction or transesterification reaction, the addition amount is 0.02% to 2% by weight of the total composition. If the added amount is less than 0.02% by weight, the effect as a stabilizer is not obtained, the color becomes worse, whereas if the added amount of the stabilizer exceeds 2% by weight, the reaction rate becomes long and it is difficult to obtain a high molecular weight polyester. Therefore, the addition amount of the stabilizer is preferably 0.22% by weight, and any one or two or more mixed stabilizers selected from phosphate-based stabilizers such as trimethyl phosphate, phospheric acid, triphenyl phosphate and the like are used as the stabilizer.

In short, the polyester resin of the present invention is a high molecular weight polymer through a three-step reaction, the number average molecular weight of the polyester resin is 30,000 to 70,000, the weight average molecular weight is 160,000 to 600,000, the melting point is 61 to 120 degreeC, and melt index is 0.1-50 (190 degreeC, 2,160g).

In addition, since the polyester resin according to the present invention has excellent tear strength, it is possible to solve the limitation on practical use that has occurred due to the lack of tear strength in the past. For example, it is difficult to manufacture and use a garbage bag and a shopping bag with an existing aliphatic polyester resin, so it is difficult to tear, but the polyester according to the present invention has improved tearing strength by an amine group present in a molecule, thereby enabling practical use. .

Hereinafter, the present invention will be described in more detail using examples.

Example 1

The 500 ml Erlenmeyer flask was replaced with nitrogen, and then 118 g of succinic acid and 4 g of 2-amino-2-methyl-1,3-propanediol were added, followed by esterification while gradually raising the temperature to allow water to flow out. At this time, after fixing at a temperature of 200 ° C. and completely flowing out the theoretical amount of water, 88 g of ethylene glycol and 0.1 g of tetrabutyl titanate as a catalyst were added to the 500 ml Erlenmeyer flask, and the temperature was raised in a nitrogen stream. The reaction is carried out for 2 hours at < RTI ID = 0.0 > Then, 0.1 g of antimony acetate, 0.2 g of dibutyl tin oxide, 0.07 g of tetrabutyl titanate, and 0.2 g of trimethyl phosphate were added as a stabilizer. Then, the temperature was raised and polycondensation reaction was performed for 170 minutes at 245 degreeC under reduced pressure of 0.3 Torr. At this time, the sample collected had a melt index (190 ° C, 2160g) of 8, a number average molecular weight of 37,400, a weight average molecular weight of 210,000, and a melting point of 98 ° C.

Example 2

The 500 mL Erlenmeyer flask was replaced with nitrogen, and then 118 g of succinic acid and 1 g of 3-aminobenzyl alcohol were added, followed by esterification while gradually raising the temperature to allow water to flow out. At this time, after fixing at a temperature of 200 ° C. and completely flowing out the theoretical amount of water, 90 g of ethylene glycol and 0.1 g of tetrabutyl titanate as a catalyst were added to the 500 ml Erlenmeyer flask, and the temperature was raised in a nitrogen stream. The reaction is carried out for 2 hours at < RTI ID = 0.0 > Then, 0.1 g of antimony acetate, 0.2 g of dibutyl tin oxide, 0.07 g of tetrabutyl titanate, and 0.2 g of trimethyl phosphate were added as a stabilizer. Subsequently, the temperature was raised and the polycondensation reaction was carried out at 245 ° C. under a reduced pressure of 0.3 Torr for 200 minutes. The sample collected at this time had a melt index (190 ° C, 2160g) of 9, a number average molecular weight of 37,000, a weight average molecular weight of 290,000, and a melting point of 98 ° C.

Example 3

The 500 ml Erlenmeyer flask was replaced with nitrogen, followed by addition of 29.2 g of adipic acid, 96.2 g of succinic acid, and 1 g of 4-amino-1,3-propanediol, followed by esterification while gradually raising the temperature to allow water to flow out. At this time, after fixing at a temperature of 200 ° C. and completely flowing out the theoretical amount of water, 130 g of 1,4-butanediol and 0.1 g of tetrabutyl titanate as a catalyst were added to the 500 ml Erlenmeyer flask to increase the temperature in a nitrogen stream. Then, the reaction is carried out at 200 ° C. for 2 hours to allow the theoretical amount of water to flow out. Then, 0.1 g of antimony acetate, 0.2 g of dibutyl tin oxide, 0.07 g of tetrabutyl titanate, and 0.2 g of trimethyl phosphate were added as a stabilizer. Subsequently, the temperature was raised and the polycondensation reaction was carried out at 245 ° C. under a reduced pressure of 0.3 Torr for 200 minutes. The sample thus collected had a melt index (190 ° C, 2160g) of 8, a number average molecular weight of 33,000, a weight average molecular weight of 190,000, and a melting point of 90 ° C measured by the DSC method.

Example 4

After replacing the 500 ml Erlenmeyer flask with nitrogen, 118 g of succinic acid and 1 g of 4-aminophenol were added, followed by esterification while gradually raising the temperature to allow water to flow out. At this time, after fixing at a temperature of 200 ° C. and completely flowing out the theoretical amount of water, 130 g of 1,4-butanediol and 0.1 g of tetrabutyl titanate as a catalyst were added to the 500 ml Erlenmeyer flask to increase the temperature in a nitrogen stream. Then, the reaction is carried out at 200 ° C. for 2 hours to allow the theoretical amount of water to flow out. Then, 0.1 g of antimony acetate, 0.2 g of dibutyl tin oxide, 0.07 g of tetrabutyl titanate, and 0.2 g of trimethyl phosphate were added as a stabilizer. Then, the temperature was raised and polycondensation reaction was performed for 220 minutes at 245 degreeC under reduced pressure of 0.3 Torr. The sample thus obtained had a melt index (190 ° C., 2160 g) of 9, a number average molecular weight of 34,000, a weight average molecular weight of 230,000, and a melting point of 115 ° C. measured by the DSC method.

Example 5

The 500 mL Erlenmeyer flask was replaced with nitrogen, and then 118 g of succinic acid and 0.5 g of 2-amino-4-nitrophenol were added, followed by esterification while gradually raising the temperature to allow water to flow out. At this time, after fixing at a temperature of 200 ° C. and completely flowing out the theoretical amount of water, 130 g of 1,4-butanediol and 0.1 g of tetrabutyl titanate as a catalyst were added to the 500 ml Erlenmeyer flask to increase the temperature in a nitrogen stream. Then, the reaction is carried out at 200 ° C. for 2 hours to allow the theoretical amount of water to flow out. Then, 0.1 g of antimony acetate, 0.2 g of dibutyl tin oxide, 0.07 g of tetrabutyl titanate, and 0.2 g of trimethyl phosphate were added as a stabilizer. Subsequently, the temperature was raised and the polycondensation reaction was carried out at 245 ° C. under a reduced pressure of 0.3 Torr for 200 minutes. The sample thus collected had a melt index (190 ° C., 2160 g) of 17, a number average molecular weight of 310,000, a weight average molecular weight of 180,000, and a melting point of 115 ° C. measured by the DSC method.

Comparative Example 1

After replacing the 500 ml Erlenmeyer flask with nitrogen, 108 g of 1,4-butanediol and 118 g of succinic acid were added thereto. The temperature was raised in a nitrogen stream, and nitrogen was stopped at 140 to 200 ° C. for 5 hours to carry out esterification reaction by condensation over 1.5 hours under a reduced pressure of 20 to 2 mmHg.

At this time, the number average molecular weight of the sample collected was 4,900, and the weight average molecular weight was 11,200.

Subsequently, 0.2 g of catalyst tetraisopropyltitanium was added under an atmospheric nitrogen stream. And the temperature was raised and the deglycol reaction was performed for 6 hours under reduced pressure of 15-0.2 mmHg at the temperature of 220 degreeC. The sample collected had a number average molecular weight of 16,100 or a weight average molecular weight of 44,100. Melting | fusing point measured by the DSC method of the said sample is 118 degreeC.

Comparative Example 2

After replacing the 500 ml Erlenmeyer flask with nitrogen, 92 g of ethylene glycol, 118 g of succinic acid, and 0.07 g of catalyst tetrabutyl titanate were added thereto. The temperature was raised in a nitrogen stream, and nitrogen was stopped at 200 ° C. for 2 hours, followed by esterification by condensation over 0.5 hours under a reduced pressure of 20 to 2 mmHg.

Subsequently, 0.07 g of catalyst tetrabutyl titanate, 0.45 g of dibutyl tin oxide, and 0.2 g of trimethyl phosphate as stabilizers were added under a nitrogen stream at atmospheric pressure. The deglycol reaction was carried out for 18 hours under a reduced pressure of 15 to 0.2 mmHg at a temperature of 250 ° C. The sample collected had a number average molecular weight of 9,000 or a weight average molecular weight of 32,000. Melting | fusing point measured by the DSC method of the said sample is 100 degreeC.

Comparative Example 3

After replacing the 500 ml Erlenmeyer flask with nitrogen, 108 g of 1,4-butanediol, 21.9 g of adipic acid and 100.3 g of succinic acid were added thereto. The temperature was raised in a nitrogen stream, and nitrogen was stopped at 200 ° C. for 2 hours, followed by esterification by condensation over 0.5 hours under a reduced pressure of 20 to 2 mmHg.

Subsequently, 0.07 g of catalyst tetraisopropyltitanium, 0.45 g of dibutyl tin oxide, and trimethyl phosphate as a stabilizer were added under a nitrogen stream at atmospheric pressure. The temperature was raised and deglycol reaction was performed at a temperature of 250 ° C. under a reduced pressure of 15 to 0.2 mmHg for 3.2 hours. The sample collected had a number average molecular weight of 31,000 or a weight average molecular weight of 84,000. Melting | fusing point measured by the DSC method of the said sample is 95 degreeC.

Comparative Example 4

After replacing the 500 ml Erlenmeyer flask with nitrogen, 92 g of ethylene glycol, 118 g of succinic acid, 0.5 g of glycerin, and 0.07 g of catalytic tetrabutyl titanate were added thereto. The temperature was raised in a nitrogen stream, and nitrogen was stopped at 200 ° C. for 2 hours, followed by esterification by condensation over 0.5 hours under a reduced pressure of 20 to 2 mmHg.

Subsequently, 0.07 g of catalyst tetrabutyl titanate, 0.45 g of dibutyl tin oxide, and 0.2 g of tetraisopropyl titanium stabilizer trimethyl phosphate were added under an atmospheric nitrogen stream. The temperature was raised and deglycol reaction was performed for 2.5 hours under reduced pressure of 15-0.2 mmHg at the temperature of 250 degreeC. The sample collected had a number average molecular weight of 27,000 or a weight average molecular weight of 221,000. Melting | fusing point measured by the DSC method of the said sample is 99 degreeC.

To prepare a polyester resin by the method of Examples 1 to 5 using the method according to the invention, compared to the polyester resin prepared according to the conventional method the content of the composition and the analysis results according to the following Table 2 Shown in In the present invention, the melting point was measured using a PerkinElmer DSC at a heating rate of 10 ° C. per minute, and the melt index (MELT INDEX) was measured at 2,160 g load at 190 ° C. according to the KS method. In addition, molecular weight was measured by GPC.

(Unit: g) Example Comparative example One 2 3 4 5 One 2 3 4 Succinic acid 118 118 96.2 118 118 118 118 100.3 118 Adipic acid 29.2 21.9 Ethylene glycol 88 90 92 92 1,4-butanediol 130 130 130 108 108 glycerin 0.5 2-amino-2methyl-1,3-propanediol 4 3-aminobenzyl alcohol One 4-amino-1,3-propane diol One 4-amino phenol One 2-amino-4-nitrophenol 0.5 Tear strength Number average molecular weight 37400 37000 33000 34000 31000 16100 9000 31000 27000 Weight average molecular weight 210000 290000 190000 230000 180000 44100 32000 84000 221000 Tensile strength (㎏ / ㎠) / elongation (%) 370/500 370/500 360/800 370/400 350/500 130/100 Not measurable 350/300 220/50 Melt index 8 9 8 9 17 Side payment 60 Side payment Side payment Melting Point (℃) 98 98 90 115 115 118 100 95 99

As can be seen from the table, it can be seen that the polyester resin composition according to the present invention has a high number average molecular weight and a weight average molecular weight, a low melt index, and excellent physical properties such as tear strength.

According to the present invention, a high molecular weight sufficient to be commercialized by reacting the dicarboxylic acid component and the monomer first, followed by a three-step reaction of polycondensation by adding glycol to the reaction product and undergoing esterification or transesterification. Provided are a biodegradable polyester resin composition and a method for producing the same.

By adding and reacting the reactants in the steps described above, the problem of abrupt increase and gelation of low molecular weight polyester, which is conventionally caused by adding a polyfunctional monomer together with the dicarboxylic acid and the glycol, is solved. can do.

In addition, since the polyester resin according to the present invention has excellent tear strength, it is possible to solve the limitation on practical use that has occurred due to the lack of tear strength in the past. For example, it is difficult to manufacture and use a garbage bag and a shopping bag with an existing aliphatic polyester resin, so it is difficult to tear, but the polyester according to the present invention has improved tearing strength by an amine group present in a molecule, thereby enabling practical use. .

As such biodegradable polyester is put to practical use, it is decomposed by microorganisms at the time of disposal and finally remains as carbon dioxide and water, thereby solving the problem of plastic, which is the main culprit of global environmental pollution.

Claims (12)

(1) aliphatic (including cyclic aliphatic) containing succinic acid; (2) aliphatic (including cyclic aliphatic) containing any one or more selected from 1,4-butanediol and ethylene glycol; (3) Condensation reaction, esterification reaction and transesterification reaction in the presence of a monomer containing glycol as a main component and one or more hydroxyl groups and amine groups as functional groups of 0.1 to 30% by weight relative to the theoretical weight of polyester. The number average molecular weight is 30,000-70,000, the weight average molecular weight is 160,000-600,000, the melting point is 61-120 ° C, the melt viscosity (190 ° C, 2,160g) ) Is 0.1 to 50 polyester resin composition and production method. The reaction product according to claim 1, wherein the dicarboxylic acid and the monomer are subjected to any one of condensation reaction, esterification reaction and transesterification reaction and esterification or transesterification of the reaction product with the glycol. Polyester resin composition and production method, characterized in that obtained by the polycondensation reaction of the reaction product The polyester resin composition and the method according to claim 1, wherein the glycol and the dicarboxylic acid are added in a ratio of 1: 1.1-2. The polyester resin composition according to claim 1, wherein the monomer is a benzene derivative including a benzene ring in its molecule, including one or two hydroxyl groups and an amine group, respectively, as functional groups. The polyester resin composition according to claim 1, wherein the monomer is a compound including one or two hydroxyl groups and an amine group as functional groups, and an amide group in the molecule thereof. According to claim 1, wherein the monomer is 3-amino-1-propanol, 1-amino-2-propanol, 2-amino-1-butanol, 4-amino-1-butanol, 3-amino-2,2-dimethyl propanol, 6-amino-1-hexanol, 2-amino-1,3-propanediol, 2-amino-2-methyl-1,3-propanediol, 2,4-diamino-6-hydroxy-5-mercaptopyrimidine, 4, 5-diamino-6-hydroxy-2-mercapto pyrimidine, 3,4-diamino-5-hydroxypyrazole sulphate, 2,4-diamino-6-hydroxy pymidine monohydrate, 4,6-diamino-2-hydroxy-1,3, 5-trizine, 2-aminobenzyl alcohol, 3-aminobenzyl alcohol, 4-aminobenzyl alcohol, 2-aminophenol, 3-aminophenol, 4-aminophenol, 2-amino-4-methylphenol, 2-amino-5-methylphenol, 4-amino -3-methylphenol, 2-amino-4-nitrophenol, 2,4-diaminophenol-dihydro chloride, 2,6-dihydroxybenzamide, 3,5-dihydroxybenzamide, 2,4-dihydroxybenz hydrazide, 3,4-dihydroxybenzhydrazide, 3,5 Polyester resin composition, characterized in that any one or a mixture of two or more selected from -dihydroxybenzhydrazide is used. (1) an aliphatic (including cyclic aliphatic) dicarboxylic acid (or anhydride thereof) containing succinic acid and a hydroxyl group and an amine group, each of 0.1 to 30% by weight based on the theoretical weight of polyester (2) A first step of performing any one or two or more reactions selected from a condensation reaction, an esterification reaction, and a transesterification reaction at a temperature of 160 to 240 ° C. by adding two or more monomers, (3) an aliphatic (including cyclic aliphatic) glycol containing any one or more selected from 1,4-butanediol and ethylene glycol is added to the first reaction product, and esterification reaction or transesterification is performed at a temperature of 200 to 220 ° C. A second step of carrying out the reaction, Polyester resin, characterized in that consisting of a third step of producing a high molecular weight polyester by polycondensation (polycondensation) of the second reaction product polyester at a temperature of 210 ~ 270 ℃ and a vacuum of 0.005 ~ 10torr Manufacturing method. 8. The method of claim 7, wherein the glycol and the dicarboxylic acid are added in a 1: 1.1 to 2 molar ratio. 8. The method of claim 7, wherein the catalyst is added at 0.02% by weight to 2% by weight based on the total weight of the composition at the beginning or the end of the esterification or transesterification reaction of the second step. 10. The method according to claim 7 or 9, wherein tetrabutyl titanate, calcium acetate, antimony oxide, dibutyl tin oxide, zinc acetate, antimonia acetate, antimony glycolate at the beginning or the end of the second esterification reaction. , Tetrapropyl titanate, any one or two or more mixed catalyst selected from polyester resin manufacturing method characterized in that used. 8. The method of claim 7, wherein the stabilizer is added at 0.02% by weight to 2% by weight based on the total weight of the composition at the beginning or the end of the esterification or transesterification of the second step. 12. The polyester resin according to claim 7 or 11, wherein any one or two or more mixed stabilizers selected from trimethyl phosphate, phospheric acid and triphenyl phosphate are used at the beginning or the end of the second esterification reaction. Manufacturing method.