KR101644114B1 - Resin composition comprising polyalkylene carbonate and polyester - Google Patents

Abstract

The present invention relates to a resin composition comprising a polyalkylene carbonate and an aromatic / aliphatic polyester and having excellent biodegradability, mechanical properties and thermal properties, and excellent weldability with other resin films, and having a function as a tie-layer The resin composition can be used in various applications such as various films, sheets, disposable articles, electronic products, and automobile interior materials.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition comprising a polyalkylene carbonate and a polyester,

The present invention relates to a composition comprising a polyalkylene carbonate and an aromatic / aliphatic polyester. More particularly, the present invention relates to a composition having excellent biodegradability, mechanical properties and thermal properties, and excellent weldability with other resin films, ). The resin composition can be used in various applications such as various films, sheets, disposable articles, electronic products, and automobile interior materials.

Recently, as interest in environmental protection has increased and various regulations have been strengthened, studies for substituting biodegradable polymers for disposable articles, packaging films and medical supplies, which are difficult to recycle derived from petroleum-derived compounds, have continued have. Plastics Minimize the environmental pollution by decomposing biodegradable polymers that are decomposed by microorganisms existing in nature at the time of disposal into water, CO ₂ , CH ₄ , biomass, humus, and other natural byproducts. Much research has been done on. Biodegradable synthetic polymers include aliphatic polyesters such as polycaprolactone (PCL), poly (butylene succinate) (PBS), poly (butylene adipate) (PBA), poly (butylene succinate-co-butylene adipate) ) Were developed first. These aliphatic polyesters are excellent in biodegradability due to microorganisms, but have low mechanical and thermal properties and thus have a limit in replacing general-purpose polymers such as polyethylene (PE) in various applications.

In order to compensate for the disadvantages of such aliphatic polyesters, various aliphatic / aromatic biodegradable copolymers having controlled molar ratio of aliphatic dicarboxylic acid / aromatic dicarboxylic acid have been developed by Showa Denko, Eastman Chemical Co., and BASF, Or to replace non-degradable general-purpose polymers in various applications where they are discarded after a short period of use. Poly (butylene adipate-co-terephthalate) (PBAT) was developed to replace polyethylene as a representative aliphatic / aromatic biodegradable polyester copolymer with poly (butylene adipate-co-succinate-co-terephthalate) (PBAST). Synthetic biodegradable plastics including aliphatic polyesters and the like are relatively high in price compared with natural products, but have characteristics of excellent tensile strength, moisture resistance, and processability.

PLA and PBAT blends of synthetic aliphatic polyesters and natural product polyesters are 100% biodegradable resins. However, as PLA content increases, mechanical properties such as tensile strength, elongation, and Young's modulus of PBAT are greatly changed have.

An object of the present invention is to provide a resin composition having excellent biodegradability, mechanical and thermal properties, and excellent weldability to other resin films, and having a function as a tie-layer.

The present invention also provides a film, a sheet, and a molded article made of the resin composition, which can be used in various applications such as disposable articles, electronic products, and automotive interiors.

In order to achieve the above object, the present invention provides a resin composition comprising a polyalkylene carbonate and an aromatic / aliphatic polyester comprising a repeating unit represented by the following formula:

[Chemical Formula 1]

In Formula 1,

R ¹ to R ⁴ are each independently hydrogen, a linear or branched alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms; At least any two of R ¹ to R ⁴ may be connected to each other to form a cycloalkyl group having 3 to 10 carbon atoms.

The resin composition according to the present invention comprises a polyalkylene carbonate and an aromatic / aliphatic polyester, preferably comprising from 65 to 95% by weight of a polyalkylene carbonate, and from 35 to 5% by weight of an aromatic / aliphatic polyester have.

According to the present invention there is provided a molded article, for example a film, and a film laminate produced using the above-mentioned resin composition.

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

The polyalkylene carbonate resin used in the present invention is a resin containing a repeating unit represented by the following formula (1)

[Chemical Formula 1]

In Formula 1,

R ¹ to R ⁴ are each independently hydrogen, a linear or branched alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms; At least any two of R ¹ to R ⁴ may be connected to each other to form a cycloalkyl group having 3 to 10 carbon atoms,

and m is an integer of 10 to 1,000.

The polyalkylene carbonate can be obtained through copolymerization using an epoxide-based compound and carbon dioxide as monomers in the presence of an organometallic catalyst. The epoxide compound may be at least one compound selected from the group consisting of ethylene oxide, propylene oxide, 1-butene oxide, 2-butene oxide, isobutylene oxide, 1-pentene oxide, 2-pentene oxide, 1-hexene oxide, Pentene oxide, cyclohexene oxide, styrene oxide or butadiene monoxide, and the like, or a combination of two or more different epoxy compounds selected from the foregoing.

Such a polyalkylene carbonate may be a homopolymer containing a repeating unit represented by the above formula (1); Or a copolymer comprising two or more kinds of repeating units belonging to the general formula (1), or a copolymer comprising an alkylene oxide repeating unit and the like together with the repeating unit represented by the general formula (1).

However, the polyalkylene carbonate resin may contain one or more repeating units of the repeating unit represented by the formula (1) so that specific physical properties due to the repeating units represented by the formula (1), such as biodegradability or a low glass transition temperature, More preferably at least about 40 mole%, more preferably at least about 60 mole%, more preferably at least about 80 mole% of the copolymer.

In the repeating unit represented by the formula (1), each of R ¹ to R ⁴ independently represents hydrogen, an alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms An alkyl group or the like; R ¹ To R < ⁴ > may be connected to each other to form a cycloalkyl group having 3 to 10 carbon atoms.

At this time, R ¹ to R ⁴ may be selected as appropriate functional groups in consideration of the mechanical properties or biodegradability of the polyalkylene carbonate resin to be finally obtained. For example, when the functional group is hydrogen or a functional group having a relatively small number of carbon atoms, it may be more advantageous in terms of biodegradability, and in the case of a functional group having a relatively large number of carbon atoms, it may be advantageous in terms of mechanical properties such as strength of the resin. As a specific example, it has been reported that polyethylene carbonate is biodegraded more rapidly than polypropylene carbonate (Inoue et al. Chem . Pharm . Bull , Jpn , 1983, 31, 1400; Ree et al. Catalysis Today , 2006, 115, 288-294).

In the polyalkylene carbonate, the degree of polymerization m of the repeating unit represented by the formula (1) may be 10 to 1,000, preferably 50 to 500. The polyalkylene carbonate containing the repeating unit may have a weight average molecular weight of about 10,000 to about 1,000,000, preferably about 50,000 to about 500,000. As the polyalkylene carbonate has the above degree of polymerization and weight average molecular weight, the molded article obtained from the polyalkylene carbonate can exhibit biodegradability with appropriate mechanical properties such as strength.

Specific examples of the polyalkylene carbonate include polyethylene carbonate, polypropylene carbonate, polypentene carbonate, polyhexene carbonate, polyoctene carbonate, polycyclohexene carbonate, and copolymers thereof, preferably polyethylene carbonate, poly Propylene carbonate, and copolymers thereof.

The method for producing the polyalkylene carbonate of the present invention is not particularly limited, but can be obtained, for example, by copolymerizing an alkylene oxide with carbon dioxide. Or ring-opening polymerization of cyclic carbonates. The copolymerization of the alkylene oxide and carbon dioxide can be carried out in the presence of a metal complex compound such as zinc, aluminum or cobalt.

The aromatic / aliphatic polyester applicable to the present invention is an aromatic dicarboxylic acid or a derivative thereof, wherein the compound (a) having the formula (2), the aliphatic dicarboxylic acid or the derivative thereof is a compound (b) Is a polyester compound obtained by a polycondensation reaction with an aliphatic divalent alcohol (c) having a hydroxyl group.

(2)

ROOC-Ar-COOR '

Wherein R, R 'are hydrogen or a C1-C12 alkyl group, and Ar is an aromatic ring.

(3)

ROOC (CH ₂₎ nCOOR '

Wherein R, R 'are hydrogen or a C1-C12 alkyl group, and n is an integer from 2 to 14

[Chemical Formula 4]

In Formula 4, R ⁵ is a C 2 -C 8 alkylene group, and R ⁶ is a C 2 -C 8 alkyl group.

Examples of the aromatic dicarboxylic acid or derivatives thereof include aromatic dicarboxylic acids such as terephthalic acid, phthalic acid, isophthalic acid, naphthalene 2,6-dicarboxylic acid, diphenylsulfonic acid dicarboxylic acid, diphenylmethane dicarboxylic acid, But is not limited to, at least one selected from the group consisting of carboxylic acid, carboxylic acid, dicarboxylic acid, diphenoxyethane dicarboxylic acid, cyclohexanedicarboxylic acid, and alkylene esters thereof.

Examples of the aliphatic dicarboxylic acid or its derivative include succinic acid, glutaric acid, malonic acid, oxalic acid, adipic acid, sebacic acid, azelaic acid, nonanedicarboxylic acid and their C1-C12 alkyl or aryl ester derivatives But the present invention is not limited thereto.

The aliphatic dihydric alcohol is, for example, 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,2-hexanediol, 1,3-hexanediol, 1,4-hexanediol, 1,5-hexanediol, 1,2-octanediol, , 5-octanediol, 1,6-octanediol, and the like can be used.

Preferable examples of the aromatic / aliphatic polyester may be poly (butylene adipate-co-terephthalate) (PBAT) having the general formula (5).

 [Chemical Formula 5]

In the above formula, x is an integer of 20 to 1,300, and y is an integer of 20 to 1,300.

The aromatic / aliphatic polyester may have a weight average molecular weight of from about 10,000 to about 500,000, preferably from about 30,000 to about 100,000. As the aromatic / aliphatic polyester has the weight average molecular weight, the molded article obtained from the aromatic / aliphatic polyester can exhibit biodegradability with appropriate mechanical properties such as strength.

The resin composition according to the present invention contains 65 to 95% by weight, more preferably 70 to 80% by weight of a polyalkylene carbonate, 35 to 5% by weight of an aromatic / aliphatic polyester, more preferably 30 to 20% %. If the content of the resin composition deviates from the content of the resin composition, the bonding property with other resins such as PVC and PLA is poor and the range of use as a tie-layer may be limited.

Various additives may be added to the resin composition of the present invention depending on the application. (Carbon black, titanium oxide, talc, calcium carbonate, clay, etc.), and the like, but not limited thereto. As a modifying additive, dispersant. Lubricants, plasticizers, flame retardants, antioxidants, antistatic agents, light stabilizers, ultraviolet absorbers, crystallization accelerators and the like. The various additives may be added when the pellets are produced from the polyalkylene carbonate resin composition or when the pellets are molded to produce a molded article.

Articles made of a resin composition comprising a polyalkylene carbonate and an aromatic / aliphatic polyester according to the present invention include, for example, films, sheets, filaments, nonwoven fabrics, injection molded articles and the like.

The manufacturing method of the article includes a step of forming a resin composition and a step of extruding the resin into a film. As the method of producing the resin composition of the present invention, various known methods can be mentioned. Examples of a method for obtaining a homogeneous mixture include a mixing method such as a Hensel mixer, a ribbon blender, and a blender. As the melt kneading method, a VAN Antonie Louis Barye mixer, a single-screw or twin-screw compressor, or the like can be used. The shape of the resin composition of the present invention is not particularly limited and may be, for example, a strand, a sheet, a flat plate, a pellet, or the like.

Further, one embodiment of the present invention is a film laminate comprising a film comprising a polyalkylene carbonate and PBAT. The film laminate may further comprise at least one film selected from the group consisting of a polyalkylene carbonate film and a polyvinyl chloride film, and may further include a release mold adjacent to the film comprising the polyalkylene carbonate and PBAT Films and the like.

A method of obtaining a molded article by molding the resin composition of the present invention can be carried out by a known method such as injection molding, compression molding, injection compression molding, gas injection molding, foam injection molding, inflation, T die, A calendar method, a blow molding method, a vacuum forming method, and a pressure forming method.

The composition comprising the polyalkylene carbonate and the aromatic / aliphatic polyester according to the present invention has excellent biodegradability, mechanical properties and thermal properties, and is excellent in weldability to other resin films and functions as a tie-layer , Various films, sheets, disposable items, electronic products, and automobile interiors.

1 shows a film laminate comprising a film made of a composition comprising a polyalkylene carbonate and an aromatic / aliphatic polyester according to an example of the present invention, and a PVC film and a polyalkylene carbonate 100% film, It is a schematic diagram showing a sieve.

Best Mode for Carrying Out the Invention Hereinafter, preferred embodiments are described to facilitate understanding of the present invention. However, the following examples are intended to illustrate the present invention without limiting it thereto.

Production Example 1 : Preparation of polyethylene carbonate resin

A polyethylene carbonate resin was prepared by copolymerizing ethylene oxide with carbon dioxide using a diethyl-zinc catalyst in the following manner (Journal of Polymer Science B 1969, 7, 287; Journal of Controlled release 1997, 49, 263).

A dry diethyl-zinc catalyst (1 g) and 10 mL of dioxane solvent were placed in an autoclave reactor equipped with a stirrer, and 0.1 g of dilute purified water was added to 5 mL of dioxane solvent while stirring slowly. Carbon dioxide was charged at a pressure of about 10 atm and then stirred at 120 DEG C for 1 hour. Thereafter, purified ethylene oxide (10 g) was charged, carbon dioxide was filled again at about 50 atm, and the temperature was adjusted to 60 ° C, and the reaction was carried out for about 48 hours. After the reaction, unreacted ethylene oxide was removed under reduced pressure and dissolved in a dichloromethane solvent. Washed with an aqueous hydrochloric acid solution (0.1 M) and precipitated in a methanol solvent to obtain a polyethylene carbonate resin. The recovered resin was about 15 g, and its formation was confirmed by nuclear magnetic resonance spectrum, and the weight average molecular weight analyzed by GPC was 230,000.

Example  1 to 4: Preparation of resin composition

The polyethylene composition prepared in Preparation Example 1 and PBAT (weight average molecular weight: 48,000, manufacturer: BASF) were mixed at the ratios shown in the following Table 1 to prepare resin compositions. Prior to compression, the PEC was dried overnight in a 40 ° C vacuum oven and the PBAT was dried in a 70 ° C vacuum oven for 4 hours.

The resin composition was prepared in the form of pellets using a twin screw extruder (BA-19, manufactured by BAUTECH). The resin obtained by compression was dried in a vacuum oven at 40 ° C. overnight, and then a dog-born specimen was prepared and the mechanical strength was measured using a universal testing machine (UTM).

division PEC (g) PBAT (g) PLA (g) Example 1 70 30 0 Example 2 80 20 0 Example 3 90 10 0 Example 4 95 5 0 Comparative Example 1 100 0 0 Comparative Example 2 0 100 0 Comparative Example 3 0 0 100 Comparative Example 4 0 30 70 Comparative Example 5 0 25 75 Comparative Example 6 0 10 90 Comparative Example 7 0 5 95

Comparative Example  1 to 7

The resin compositions were prepared in substantially the same manner as in Example 1, and the resins were prepared in the form of pellets by using an extruder. In Comparative Examples 1 to 3, 100% of PEC, 100% of PLA and 100% of PBAT And Comparative Examples 4 to 7 were made from a resin composition containing PLA and PBAT in the composition ratio shown in Table 1 above. The PEC was the resin obtained in Preparation Example 1, PBAT was the same as in Example 1, and PLA was polylactide having a weight average molecular weight of about 230,000 (manufactured by NatureWorks).

Experimental Example  1: Property evaluation experiment

The extrudability, the pellet state and the sheet formability of each of the resin composition specimens were evaluated according to the following experimental methods for the specimens prepared in Examples 1 to 4 and Comparative Examples 1 to 7, and MI, Tg, Tensile strength, elongation and haze were measured, and the results are shown in Table 2 below.

(1) Extrusion property: The extrusion process of the resin composition was visually observed in the above-mentioned sample preparation process and evaluated in four stages of excellent (⊚), excellent (◯), moderate (△) and poor (X).

(2) Pellet state: About 20 g of the pellets containing the respective resin compositions according to the examples and comparative examples were placed in a convection oven at about 40 ° C under a load of 200 g, Minute, the state of the pellet containing each resin composition, the degree of blocking, and the like were observed with naked eyes, and the results were evaluated as excellent (?), Excellent (?), Normal (?) And poor Respectively.

(3) Sheet processability: After preheating the sheet at a temperature of 170 DEG C for 1 minute using a hot press machine, each sheet was compressed for 2 minutes under a pressure of 300 bar to provide a sheet to test the sheet formability.

(4) tensile strength (TS max, kgf / cm 2), elongation, E-Modulus (Gpa)

Three to four dumbbell specimens were prepared in accordance with ASTM D 412 using the resin compositions of the examples and comparative examples. The resin compositions were then extruded at a rate of 50 mm / min using Zwick / Roell Zwick / Tensile strength (Kg / cm ² ), elongation (%), and E-Modulus (Gpa) were measured.

Extrudability Pellet state Film processability TS Elongation Young's M (Gpa) Example 1 ○ ○ ○ 139.5 215.3 0.04 Example 2 ○ ○ ○ 123.3 256.0 0.03 Example 3 ○ ○ ○ 107.0 296.7 0.02 Example 4 ○ △ ○ 82.8 262.0 0.02 Comparative Example 1 ○ X ○ 41 125 0.01 Comparative Example 2 ○ ○ ○ 234 129.6 0.12 Comparative Example 3 ○ ○ ○ 752 3.4 2.98 Comparative Example 4 △ ○ ○ 482 12.1 2.04 Comparative Example 5 △ ○ ○ 519 15.92 2.14 Comparative Example 6 △ ○ ○ 652 14.37 2.54 Comparative Example 7 △ ○ ○ 706 11.34 2.15

Test Example  2: Evaluation of bonding property of laminated film

A film of the resin compositions prepared in Examples 1 to 4 and Comparative Examples 1 to 7 was prepared. In order to evaluate the compatibility with the film laminate, PEC, PVC, and PLA were prepared as films to be bonded.

The above PVC film was made of polyvinyl chloride (manufacturer: LG Chem) having a weight average molecular weight of 60,000 and the PET film was SH-71S manufactured by SKC. The PEC was prepared in Preparation Example 1, and polylactide (weight average molecular weight: about 230,000, manufactured by NatureWorks) and polymethylmethacrylate (weight average molecular weight: 86,000, manufactured by LG MMA) were used .

11 films prepared in Examples 1 to 4 and Comparative Examples 1 to 7 and two additional films of control PVC and PET were applied to each of the three films (PEC, PVC, and PLA) The laminate was prepared by a heat fusion method and the bonding strength was evaluated by visually observing the bonding strength when the laminate was separated by applying a force.

<Evaluation Criteria>

◎: Very good (never separated even with strong force)

○: Excellent (not easily separated even with strong force)

X: Bad (easily separated by applying a little force)

division Material (weight) PEC PVC PLA Example 1 PEC / PBAT (70/30) x o o Example 2 PEC / PBAT (80/20) x o o Example 3 PEC / PBAT (90/10) o x x Example 4 PEC / PBAT (95/5) o x x Comparative Example 1 PEC 100 o x x Comparative Example 2 PBAT 100 x ◎ o Comparative Example 3 PLA 100 x x o Comparative Example 4 PLA / PBAT (60/40) x x o Comparative Example 5 PLA / PBAT (70/30) x x o Comparative Example 6 PLA / PBAT (90/10) x x o Comparative Example 7 PLA / PBAT (95/5) x x o Comparative Example 8 PVC 100 x o x Comparative Example 9 PET 100 x o x

Claims (13)

65 to 95% by weight of a polyalkylene carbonate containing a repeating unit represented by the following formula (1); And 35 to 5% by weight of an aromatic / aliphatic polyester having a weight average molecular weight of 30,000 to 100,000; And
At least one film selected from the group consisting of a polyethylene carbonate film and a polyvinyl chloride film.
[Chemical Formula 1]

In Formula 1,
R ¹ to R ⁴ are each independently hydrogen, a linear or branched alkyl group having 1 to 20 carbon atoms, an aryl group having 6 to 20 carbon atoms, an alkenyl group having 2 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms; At least any two of R ¹ to R ⁴ may be connected to each other to form a cycloalkyl group having 3 to 10 carbon atoms;
and m is an integer of 10 to 1,000. The film laminate according to claim 1, wherein the polyalkylene carbonate has a weight average molecular weight of 10,000 to 1,000,000. The film according to claim 1, wherein the polyalkylene carbonate is at least one selected from the group consisting of polyethylene carbonate, polypropylene carbonate, polypentene carbonate, polyhexene carbonate, polyoctenecarbonate, polycyclohexene carbonate and copolymers thereof sieve. The aromatic / aliphatic polyester according to claim 1, wherein the aromatic / aliphatic polyester is an aromatic dicarboxylic acid or a derivative thereof and the compound (a) having the formula (2), the aliphatic dicarboxylic acid or the derivative thereof is the compound (b) 4, which is a polyester compound obtained by a polycondensation reaction with an aliphatic divalent alcohol (c)
(2)
ROOC-Ar-COOR '
Wherein R, R 'are hydrogen or a C1-C12 alkyl group, and Ar is an aromatic ring.
(3)
ROOC (CH ₂₎ nCOOR '
Wherein R, R 'are hydrogen or a C1-C12 alkyl group, and n is an integer from 2 to 14
[Chemical Formula 4]

In Formula 4, R ⁵ is a C 2 -C 8 alkylene group, and R ⁶ is a C 1 -C 8 alkyl group. The aromatic dicarboxylic acid or derivative thereof according to claim 4, wherein the aromatic dicarboxylic acid or derivative thereof is selected from the group consisting of terephthalic acid, phthalic acid, isophthalic acid, naphthalene 2,6-dicarboxylic acid, diphenylsulfonic acid dicarboxylic acid, diphenylmethane dicarboxylic acid, Diphenyl ether dicarboxylic acid, diphenoxy ethane dicarboxylic acid, cyclohexanedicarboxylic acid, or an alkylene ester thereof. 5. The composition of claim 4, wherein the aliphatic dicarboxylic acid or derivative thereof is selected from the group consisting of succinic acid, glutaric acid, malonic acid, oxalic acid, adipic acid, sebacic acid, azelaic acid, nonanedicarboxylic acid and their C1- And derivatives thereof. 5. The process of claim 4, wherein the aliphatic dihydric alcohol is selected from the group consisting of 1,2-propanediol, 1,2-butanediol, 1,3-butanediol, 1,2-pentanediol, Diol, 1,2-hexanediol, 1,3-hexanediol, 1,4-hexanediol, 1,5-hexanediol, 1,2-octanediol, , 1,5-octanediol, 1,6-octanediol, and the like. The film laminate according to claim 4, wherein the aromatic / aliphatic polyester is poly (butylene adipate-co-terephthalate) (PBAT) having the general formula:
[Chemical Formula 5]

In the above formula, x is an integer of 20 to 1,300, and y is an integer of 20 to 1,300. delete The film of claim 1, wherein the film comprising the polyalkylene carbonate and the aromatic / aliphatic polyester is a pigment, a dye, a carbon black, a titanium oxide, a talc, a calcium carbonate, a clay, a dispersant. Wherein the film laminate further comprises at least one additive selected from the group consisting of a lubricant, a plasticizer, a flame retardant, an antioxidant, an antistatic agent, a light stabilizer, an ultraviolet absorber, and a crystallization promoter.
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