KR20100009028A - Poly lactic acid (pla) and acrylonatrile butadiene styrene (abs) blend and its preparation process - Google Patents

Abstract

The present invention relates to a polylactic acid (PLA) / acrylonitrile butadiene styrene (ABS) blend and a method for preparing the same, and more particularly, to polylactic acid and acrylonitrile. Low viscosity polyethylene terephthalate as a compatibilizer when blending butadiene styrene relates to environmentally friendly bioplastic blends and methods for their preparation using (polyethylene terephthalate, PET) and low viscosity polycarbonate (PC).

Description

Poly Lactic Acid (PLA) and Acrylonatrile Butadiene Styrene (ABS) Blend and Its Preparation Process}

The present invention relates to a polylactic acid (PLA) / acrylonitrile butadiene styrene (ABS) blend and a method for preparing the same, and more particularly, to polylactic acid and acrylonitrile. Low viscosity polyethylene terephthalate as a compatibilizer when blending butadiene styrene relates to environmentally friendly bioplastic blends and methods for their preparation using (polyethylene terephthalate, PET) and low viscosity polycarbonate (PC).

Recently, interest in biopolymers is increasing due to consumers who want to use more environmentally friendly materials and the price increase of crude oil and global warming. Biopolymers are naturally occurring polymers found in living organisms. They are derived from renewable resources and are biodegradable. Biopolymers can be used in a variety of fields, including medicine, coatings, food and packaging materials.

Due to the changes in new environmental regulations, social interests, and growing awareness of the environment, interest in environmentally friendly materials is increasing in Korea. The concept of recycling resources in using materials has been more important since the end of the 20th century. As a result, many industries in the developed world that are leading the global economy are trying to replace increasingly petroleum-based material sources with eco-friendly materials based on natural and crop resources.

Polylactic acid is the most representative biodegradable plastic, which itself has low impact strength, thermal properties, and hydrolysis resistance, but when blended with petroleum resin acrylonitrile butadiene styrene, this disadvantage can be improved.

Research and application of auto parts using biodegradable materials are currently competitive in many automobile companies, and there are many practical advantages such as measures to reduce oil resources, reduce carbon dioxide, reduce volatile organic substances, and respond to recycling rate regulation.

The present invention relates to a polylactic acid (PLA) / acrylonitrile butadiene styrene (ABS) blend and a method for preparing the same, and more particularly, to polylactic acid and acrylonitrile. The present invention relates to an eco-friendly bioplastic blend using low viscosity polyethylene terephthalate (PET) and low viscosity polycarbonate (PC) as a compatibilizer when blending butadiene styrene and a method for preparing the same.

Polylactic acid / acrylonitrile butadiene styrene blends prepared using the above two compatibilizers are more suitable for automotive interior and exterior materials because they have better mechanical properties, thermal properties, and durability than conventional blends.

When blending polylactic acid, which is best known as bioplastic, with acrylonitrile butadiene styrene, we use a suitable compatibilizer to improve the mechanical properties and performance of the polylactic acid / acrylonitrile butadiene styrene blend. We propose a method for preparing polylactic acid / acrylonitrile butadiene styrene blend resin having excellent thermal properties.

As a result, the present invention was completed by preparing the polylactic acid / acrylonitrile butadiene styrene blend resin by adjusting the amount and the addition method of the low viscosity polyethylene terephthalate and the low viscosity polycarbonate as compatibilizers.

Accordingly, an object of the present invention is to provide a polylactic acid / acrylonitrile butadiene styrene blend resin having excellent mechanical strength and thermal properties and excellent hydrolysis resistance and a method for producing the same.

The present invention relates to a low viscosity polyethylene terephthalate and a low viscosity polycarbonate which are compatibilizers for polylactic acid / acrylonitrile butadiene styrene compared to polylactic acid / acrylonitrile butadiene styrene blends usable in automotive interior parts. It relates to a bioplastic and a manufacturing method having a mechanical and thermal property suitable for the required properties of the application part by adjusting the amount.

As described above, the present invention was able to obtain a resin composition of excellent physical properties by adjusting the low viscosity polyethylene terephthalate and low viscosity polycarbonate in an appropriate ratio when blending acrylonitrile butadiene styrene to polylactic acid. This can be applied as a substitute for acrylonitrile butadiene styrene, which is widely used in automobile interior parts.

The present invention relates to a low viscosity polyethylene terephthalate and a low viscosity polycarbonate which are compatibilizers for polylactic acid / acrylonitrile butadiene styrene compared to polylactic acid / acrylonitrile butadiene styrene blends usable in automotive interior parts. It relates to a bioplastic manufacturing method having a mechanical and thermal property suitable for the required properties of the applied parts by adjusting the amount.

The present invention is 30 to 50 parts by weight of polylactic acid and 40 to 60 parts by weight of acrylonitrile butadiene styrene; And it relates to a polymer blend resin comprising a polycarbonate and polyethylene terephthalate.

More specifically, the present invention relates to a polymer blend resin, characterized in that the content of the polycarbonate and the polyethylene terephthalate is 3 to 15% by weight relative to the polymer blend.

Polylactic acid (polylactic acid) is a thermoplastic polyester having a biodegradable polymerized lactic acid produced by the fermentation of corn sugar. Polylactic acid has excellent mechanical strength and excellent manufacturability compared to other biopolymers, and many studies are being conducted to use it as a biodegradable engineering plastic. However, polylactic acid softens around 60 ° C and has lower gas and water barrier properties than other petroleum-based polymers.

The acrylonitrile butadiene styrene (ABS) resin is a terpolymer copolymer composed of three monomers (monomers) of AN (Acrylonitrile), BD (Butadiene), and SM (Styrene Monomer). ABS resin has the advantage of being able to be developed in various grades by adjusting the composition ratio of three main monomers, reinforcing various pigments and additives, adding heat-resistant agents, adding flame retardants, and controlling molecular weight.

Looking at the development history of ABS, first, PS (Polystyrene), a polymer of SM, has the advantages of processability and transparency, but it is easily broken. Was developed. In addition, AS resins have been developed by copolymerizing strong AN and SM to improve chemical resistance of PS resins and to increase impact strength. Putting these two together, ABS resin was developed by US Rubber in 1947.

In the manufacturing method of ABS, it is common to mix (blend) the interpolymer of acrylonitrile and butadiene and the interpolymer of styrene and butadiene to obtain a mixed resin having the properties of each interpolymer simultaneously. Different combinations of components in the interpolymer will result in subtle changes in product performance and will therefore vary depending on the application. Generally easy to process, high impact resistance and good heat resistance.

ABS is 93 ° C., while polyethylene has a heat resistance of 80 ° C., while ABS is 4.5, while impact resistance of polyethylene is 0.8. The impact resistance 4.5 is so strong that it will not break even if it is hit by an iron hammer, so it is used as a metal substitute for industrial parts such as automobile parts, helmets, electric machine parts, and spinning machine parts.

Polymer compatibilizers are added to effectively mix two or more types of polymers. A polymer blend is a method of innovatively improving physical properties by simply mixing two or more polymers that are already commercially produced and used as a new polymer development method. However, most of the polymer pairs are incompatible, and thus must be overcome to achieve the desired purpose. Various methods of commercialization have been studied and reported so far, but it is most effective to use a compatibilizer as an additive, and most commercially successful polymer alloys are prepared using a compatibilizer addition method.

As the polymer compatibilizer, graft or block copolymer having the same chemical structure as the blend component is known to be effective, and pre-made block and graft copolymer and in-situ reactions are determined depending on how these compatibilizers are introduced during the mixing process. It is divided into a type compatibilizer. In the case of reactive compatibilizers, block or graft copolymers are introduced at the interface through chemical reaction between the compositional polymer and the functional groups introduced into the compatibilizer during melt mixing.

In the present invention, polycarbonate and polyethylene terephthalate are used as the polymer compatibilizer.

Polycarbonate is a general term for a polymer having a carbonate ester bond repeatedly in a molecular main chain, also commonly referred to as a polycarbonate ester. The polycarbonate ester of bisphenol A is famous for its practical use, and it was also used in the astronaut's space cap in the US Apollo program, and it was industrialized in each country.

Practical thermoplastic resins are polycarbonates of bisphenol A. It is an engineering plastic that is transparent and has excellent mechanical properties (particularly impact resistance), heat resistance, cold resistance, and electrical properties, and is nontoxic and self-extinguishing. It was also used in the astronaut's astronaut who performed lunar activity in the US Apollo program. First synthesized by Schnell in Germany in 1956, film and molding materials were released from Bayer AG in 1958. It was then industrialized in various countries, including the US General Electric Company.

Two manufacturing methods are used industrially by the solvent method by the interfacial polycondensation reaction of bisphenol A and phosgene, and the melting method by the transesterification reaction of bisphenol A and diphenyl carbonate. The molecular weight is more than 20,000 thousands. It is used for electric parts such as various switches, hair dryers, fan parts, and mechanical parts such as fans, helmets, camera bodies, fire extinguisher covers, and the like.

Polyethylene terephthalate is a saturated polyester obtained by condensation polymerization of terephthalic acid and ethylene glycol, commonly called PET. As a crystalline plastic, it is excellent in heat resistance, rigidity, electrical properties, oil resistance, etc., but is not suitable for injection molding due to the slow crystallization. Used as a raw material for synthetic fibers and films.

To obtain PET, dimethyl terephthalate and ethylene glycol are heated at 150 to 230 ° C. to obtain Bis (β-hydroxyethyl) terephthalate by transesterification. When Bis (β-hydroxyethyl) terephthalate is heated to 270 to 300 ° C. under 1 torr, polycondensation is carried out to give ethylene glycol to give PET. Another method of obtaining Bis (β-hydroxyethyl) terephthalate is to react at about 230 ° C. while applying high-purity terephthalic acid and ethylene glycol under pressure. Excellent heat resistance, stiffness, electrical properties, and even at high temperatures for a long time, the ultimate strength is only slightly reduced. Because it belongs to crystalline plastics, it has good resistance to oils such as diesel oil. However, due to ester bonds in the molecular chain, molded products are prone to change when they are immersed in acid or alkali over high temperature and long time. Due to the slow crystallization, it is not suitable for injection molding. Therefore, a method such as adding a nucleating agent or making the crystal microcrystalline is used.

In order to use as an engineering plastic, glass fiber reinforced PET improves mechanical strength and dimensional stability. Reinforced PET has excellent heat resistance, fatigue strength and electrical properties among thermoplastic resins and is less affected by temperature and humidity. It is widely used as a raw material for synthetic fibers and films.

The present invention is 30 to 50 parts by weight of polylactic acid and 40 to 60 parts by weight of acrylonitrile butadiene styrene; And 3 to 15 wt% of polycarbonate and polyethylene terephthalate relative to the polymer blend.

If the content of polylactic acid is less than 30 parts by weight, it is not meaningful as a bio material, that is, it does not have biodegradability. In addition, when more than 50 parts by weight has a disadvantage of low impact strength and heat deformation temperature.

Acrylonitrile butadiene styrene (ABS) resin has excellent heat resistance and impact resistance, and is suitable for automotive materials. If the weight part acrylonitrile butadiene styrene content is less than 40 parts by weight, there is a disadvantage that the impact strength and heat deformation temperature is low. In addition, when the acrylonitrile butadiene styrene is more than 60 parts by weight, the content of polylactic acid is small and does not have biodegradability.

In the present invention, polycarbonate and polyethylene terephthalate are introduced as a compatibilizer, but when the content of the use agent is less than 3% by weight, there is a problem of poor mechanical, thermal properties and hydrolysis resistance. In addition, when the compatibilizer exceeds 15% by weight, the inherent physical properties of the polycarbonate and the polyethylene terephthalate, which are polymers introduced as the compatibilizer, are expressed and thus are not suitable for automotive materials.

The present invention comprises the steps of mixing the polylactic acid and polycarbonate; Mixing acrylonitrile butadiene styrene and polyethylene terephthalate; Preparing a polymer mixture by mixing the polylactic acid and polycarbonate mixture with the acrylonitrile butadiene styrene and polyethylene terephthalate mixture; And a step of extruding the polymer mixture.

More specifically, the present invention relates to a method for producing a polymer blend resin, characterized in that the extrusion is extruded at 200 ~ 220 ℃.

Hereinafter, the present invention will be described in more detail based on the following examples, which are not intended to limit the present invention.

Example  One. PLA  36 g, ABS  54 g, PC  5 g, PET  Polymers containing 5 g Blend

36 g of polylactic acid and 54 g of acrylonitrile butadiene styrene are used, 5 g of polycarbonate is mixed with polylactic acid, and 5 g of polyethylene terephthalate is mixed with acrylonitrile butadiene styrene at 210 ° C. Extruded through an extruder at to prepare a polymer blend resin.

Example  2. PLA  36 g, ABS  54 g, PC  7 g, PET  Polymers containing 3 g Blend

36 g of polylactic acid and 54 g of acrylonitrile butadiene styrene are used, 7 g of polycarbonate is mixed with polylactic acid, and 3 g of polyethylene terephthalate is mixed with acrylonitrile butadiene styrene at 210 ° C. Extruded through an extruder at to prepare a polymer blend resin.

Example  3. PLA  36 g, ABS  54 g, PC  3 g, PET  Polymer containing 7 g Blend

36 g of polylactic acid and 54 g of acrylonitrile butadiene styrene are used, 7 g of polycarbonate is mixed with polylactic acid, and 3 g of polyethylene terephthalate is mixed with acrylonitrile butadiene styrene at 210 ° C. Extruded through an extruder at to prepare a polymer blend resin.

Example  4. PLA  45 g, ABS  45 g, PC  5 g, PET  Polymers containing 5 g Blend

45 g of polylactic acid and 45 g of acrylonitrile butadiene styrene are mixed, 5 g of polycarbonate is mixed with polylactic acid, and 5 g of polyethylene terephthalate is mixed with acrylonitrile butadiene styrene at 210 ° C. Extruded through an extruder at to prepare a polymer blend resin.

Example  5. PLA  45 g, ABS  45 g, PC  7 g, PET  Polymers containing 3 g Blend

Use 45 g of polylactic acid and 45 g of acrylonitrile butadiene styrene, mix 7 g of polycarbonate with polylactic acid, and mix 3 g of polyethylene terephthalate with acrylonitrile butadiene styrene at 210 ° C. Extruded through an extruder at to prepare a polymer blend resin.

Example  6. PLA  45 g, ABS  45 g, PC  3 g, PET  Polymer containing 7 g Blend

Using 45 g of polylactic acid and 45 g of acrylonitrile butadiene styrene, 3 g of polycarbonate is mixed with polylactic acid, and 7 g of polyethylene terephthalate is mixed with acrylonitrile butadiene styrene at 210 ° C. Extruded through an extruder to produce a polymer blend resin.

Comparative example  One. PLA  50 g, ABS  Polymer containing 50 g Blend

50 g of polylactic acid and 45 g of acrylonitrile butadiene styrene are mixed and extruded through an extruder at 210 ° C. to prepare a polymer blend resin.

Test Example . The tensile strength , Impact strength and heat deflection temperature

The physical properties of the samples of Examples 1 to 6 and Comparative Example 1 were measured as shown in Table 1 below.

The tensile test was conducted at room temperature using a universal testing machine according to ASTM D 638 (Standard Test Method for Tensile Properties of Plastics), and the tensile strength of the sample was measured (tensile strength [Pa] = maximum load [ N] / cross sectional area of the initial sample [m ² ], elongation [%] = extended length to break point / initial length).

Heat Distortion Temperature was measured according to ASTM D648 and the load was 4.6 kg / cm.

Impact strength was measured using the Izod test method specified in ASTM D256.

Mechanical and thermal properties division Tensile Strength (kgf / cm ² ) Impact Strength (kgfcm / cm) HDT (℃) Example 1 712 12.5 108 Example 2 702 11.5 106 Example 3 695 11.0 105 Example 4 725 9.5 102 Example 5 711 8.7 100 Example 6 705 8.2 98 Comparative Example 1 536 7.2 89

In summary, as shown in Table 1, when the ratio of the compatibilizer is mixed in each of 5%, it can be confirmed that it has the best physical properties, the tensile strength increases as the PLA content increases but the impact strength and thermal deformation It can be seen that the temperature decreases somewhat.

The use of the compatibilizer is because polylactic acid is dispersed in acrylonitrile butadiene styrene in several micron size domains, as shown in FIG.

1 is a diagram of a polymer blend incorporating a compatibilizer.

<Description of the symbols for the main parts of the drawings>

10: ABS 20: polylactic acid

30: PC, PET

Claims (4)

30 to 50 parts by weight of polylactic acid and 40 to 60 parts by weight of acrylonitrile butadiene styrene; And polycarbonate and polyethylene terephthalate. The method of claim 1, The content of the polycarbonate and the polyethylene terephthalate is a polymer blend resin, characterized in that 3 to 15% by weight relative to the polymer blend. Mixing polylactic acid and polycarbonate; Mixing acrylonitrile butadiene styrene and polyethylene terephthalate; Preparing a polymer mixture by mixing the polylactic acid and polycarbonate mixture with the acrylonitrile butadiene styrene and polyethylene terephthalate mixture; Extruding the polymer mixture; Polymer blend resin production method comprising a. The method of claim 3, wherein The extrusion is a method of producing a polymer blend resin, characterized in that the extrusion at 200 ~ 220 ℃.

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