KR20050114459A - Polycarbonate/abs resin nanocomposites containing montmorillonite - Google Patents

Abstract

The nanocomposite prepared by dispersing montmorillonite in the polycarbonate and acrylonitrile butadiene styrene copolymer resin according to the present invention is a resin capable of simultaneously improving mechanical properties such as tensile strength and impact resistance, By further including methacrylate, polyphenylene oxide, and styrene maleic hydride copolymer, physical properties such as tensile strength and heat resistance may be further improved, thereby enabling various applications in electric and electronic products.

Description

Polycarbonate / ABS Resin Nanocomposites Containing Montmorillonite

The present invention relates to a polycarbonate / ABS resin nanocomposite comprising montmorillonite. More specifically, by dispersing montmorillonite (MMT) in polycarbonate (PC) and acrylonitrile butadiene styrene (ABS) copolymer resins, mechanical properties such as tensile strength and impact resistance are simultaneously improved to provide electrical And polycarbonate / ABS resin nanocomposites usefully used in electronic products.

In general, inorganic / organic composite materials exist in a state in which inorganic particles are agglomerated in a polymer, and in this case, inorganic particles only increase the strength of the composite material slightly. However, in organic / inorganic nanocomposites, various physical properties have been obtained by peeling and dispersing inorganic particles at a nano-scale in polymer materials such as thermoplastic resins and thermosetting resins. Of these, clay-dispersed polymer nanocomposites induce polymer layer separation by infiltrating polymer resin between layers of clay minerals such as montmorillonite having a silicate layer structure, and mechanically dissociating and dispersing nanoscale plate silicates in polymer resin. The physical properties of general purpose polymers having poor physical properties can be improved. Among the advantages that can be obtained through nanocomposite materialization of polymers, the barrier materials are improved by improving mechanical properties such as strength and elastic modulus, increasing heat resistance such as increasing heat deformation temperature, imparting flame retardancy, and resistance to gas permeability. material).

One of the clay minerals, montmorillonite, has a highly polar structure in which ions such as sodium (Na) are filled between the silicate layers and hydroxyl groups (OH ⁻ ) are present. Therefore, when montmorillonite is added to the hydrophobic polymer, dispersion into the resin and delamination into layers become very difficult. Therefore, studies have been actively conducted to delaminate and disperse montmorillonite into nanoscales by polymerizing lipophilic through a pretreatment process in which a low molecular weight intercalant is inserted into the structure of montmorillonite. Thus, a composite material in which montmorillonite or the like is added to the resin at a nanoscale is called a nanocomposite material. The nanocomposite is composed of exfoliated nanocomposite in which the silicate layer is completely dispersed in the resin and intercalated nanocomposite and montmorillonite in which the polymer is inserted between the silicate layers at regular intervals. It can be divided into phase-separated nanocomposites. However, plate silicates, which are the basic units of clay minerals, are difficult to uniformly disperse the clay layer in the polymer matrix due to the strong attraction between the plates. Therefore, the most important thing in the production of polymer nanocomposites is how to release the layered clay into the polymer. Since montmorillonite is a highly polar hydrophilic structure consisting of a combination of silica tetrahedral and alumina octahedral structures, it has been highly advanced in its modification to suit the properties of various polymers with high lipophilic properties, but recently montmorillonite In the case of montmorillonite, which is modified in stages according to the degree of organication, is commercialized by grade. However, even when using the commercialized montmorillonite, it is important to select the appropriate type of modified montmorillonite according to the desired polymer.

On the other hand, the molding technology of the nanocomposite material can be largely divided into a solution method, a polymerization method and a melt insertion method according to the method of inserting the polymer between the silicate layer of montmorillonite. The solution method is a method of preparing a nanomaterial by mixing and drying a polymer together with montmorillonite in a solvent. However, the solution method requires the use of excess solvent, and in order to obtain the final product, the solvent has to be removed separately. Since the interaction with montmorillonite varies depending on the type of material used as the solvent, the type of solvent is montmorillonite in the polymer. There is a possibility of affecting the dispersion state of. The polymerization method is a method in which a part of the monomer penetrates through the silicate layer by polymerizing in the state where montmorillonite is mixed with the raw material monomer of the polymer and then polymerized to disperse the montmorillonite in the polymer. It is a method widely used in the manufacture of some polymer nanocomposites, and since the low molecular weight monomer is intercalated, there is an advantage that the peeling of the silicate can occur relatively easily, whereas the usable monomers are limited and the manufacturing process is somewhat complicated. have.

In addition, the melt-insertion method is a mixture of the modified organic montmorillonite in the molten state by direct compounding, it can be considered the most preferable in terms of economics because it can use a processing equipment such as an existing extruder. However, it is difficult to insert the high viscosity resin into the montmorillonite layer in the molten state, and in particular, when the thermodynamic mixing is not natural, it is almost impossible to disperse dispersion. Therefore, the melting process is simple in manufacturing process, and it is possible to classify various products, so it is expected to be a commercial application.However, in order to peel the layered material on nanoscale, it is necessary to select an appropriate organic material for montmorillonite, modify the polymer resin, and polymer resin and the layered material. Development of various technologies such as the use of compatibilizers to improve the affinity of materials, the optimization of mixing and processing conditions are necessary.

In order to solve the above problems, the present invention is to provide a nanocomposite that can improve the mechanical properties such as tensile strength, impact resistance by dispersing montmorillonite in the polycarbonate and acrylonitrile butadiene styrene copolymer resin do.

The above and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention provides a nanocomposite comprising montmorillonite and polycarbonate and acrylonitrile butadiene styrene copolymer resin.

The montmorillonite may be an organic modified montmorillonite.

The montmorillonite may be modified montmorillonite organicized with a quaternary ammonium salt.

The montmorillonite may be added at 0.1 to 20% by weight based on the entire nanocomposite.

The polycarbonate may be added in an amount of 20 to 58% by weight based on the total nanocomposite, and the acrylonitrile butadiene styrene resin may be added in an amount of 40 to 70% by weight.

The nanocomposite may further comprise at least one additive selected from the group consisting of polymethyl methacrylate, polyphenylene oxide and styrene maleic hydride copolymer.

The nanocomposite is polymethyl methacrylate is added in 1 to 30% by weight based on the entire nanocomposite, the polyphenylene oxide is added in 1 to 20% by weight, the styrene maleic hydride copolymer is 1 to 20% by weight may be added.

The nanocomposite may be melt mixed using a twin screw extruder.

Hereinafter, the present invention will be described in detail.

In the present invention, it is possible to obtain a polycarbonate / ABS resin having improved physical properties by adding montmorillonite to a blend product of polycarbonate and acrylonitrile butadiene styrene copolymer resin to prepare nanocomposite resin. Polycarbonate / ABS resin is an engineering plastic widely used in the case of electrical and electronic products, etc. In order to improve the mechanical properties of the polycarbonate / ABS resin, in particular, in the present invention, the appropriate modified montmorillonite is selected, an optimum addition composition, It is intended to obtain a polycarbonate / ABS resin nanocomposite in which montmorillonite is dispersed in a polycarbonate / ABS resin through simultaneous addition with other resins.

The nanocomposite produced by the present invention comprises montmorillonite and polycarbonate and acrylonitrile butadiene styrene copolymer resin.

The montmorillonite may be unmodified montmorillonite or montmorillonite modified using an organic agent. Among them, organicated modified montmorillonite is preferable. In general, a quaternary ammonium salt is used as the organic agent.

The montmorillonite is preferably 0.1 to 20% by weight based on the entire nanocomposite. Less than 0.1% by weight of the total nanocomposite exhibits little effect due to the addition of montmorillonite, and when it exceeds 20% by weight, it is not only difficult to manufacture the resin nanocomposite, but also causes a problem of low economical efficiency due to excessive usage.

The polycarbonate may be 20 to 58% by weight based on the entire nanocomposite, and the acrylonitrile butadiene styrene resin may be 40 to 70% by weight. When the content of the polycarbonate is less than 20% by weight of the entire nanocomposite, mechanical properties of the polycarbonate are not expressed in the nanocomposite material, so that impact resistance of the nanocomposite may be lowered, and the content of the polycarbonate is 58. When the weight percentage is exceeded, the polycarbonate may be affected by montmorillonite, and the physical properties of the nanocomposite may be lowered again.

In addition, when the content of acrylonitrile butadiene styrene resin to the entire nanocomposite is less than 40% by weight, the physical properties of acrylonitrile butadiene styrene resin may not be expressed in the nanocomposite material, so that the processability of the nanocomposite material may be deteriorated. When the content of acrylonitrile butadiene styrene resin exceeds 70% by weight, physical properties such as tensile strength may decrease.

In order to further improve mechanical properties such as tensile strength and heat resistance in the nanocomposite according to the present invention, additives which may be further included in the nanocomposite are polymethylmethacrylate (PMMA) and polyphenylene oxide (polyphenylene oxide). , PPO) and styrene maleic anhydride copolymer (SMA) are preferred.

In order to increase the heat resistance of the PC / ABS resin is added PPO, SMA, etc. In this case, unlike the general tendency that the physical properties are greatly reduced due to compatibility problems, tensile strength, impact strength, tensile modulus increases.

The polymethyl methacrylate is 1 to 30% by weight based on the total nanocomposite, 1 to 20% by weight of the polyphenylene oxide, 1 to 20% by weight of the styrene maleic hydride copolymer. .

When the content of polymethyl methacrylate is less than 1% by weight, the effect of polymethyl methacrylate is not expressed in the nanocomposite material, and when the content of polymethyl methacrylate is more than 30% by weight, polymethylmethacrylate Due to the excessive rate, impact resistance and the like of the nanocomposite may be lowered.

When the content of polyphenylene oxide is less than 1% by weight, the effect of polyphenylene oxide is not expressed in the nanocomposite material, and when the content of polyphenylene oxide is more than 20% by weight, due to the excessive amount of polyphenylene oxide. Impact resistance and the like of the nanocomposite may be lowered.

In addition, when the content of the styrene maleic hydride copolymer is less than 1% by weight, the influence of the styrene maleic hydride copolymer is not expressed in the nanocomposite material, and the content of the styrene maleic hydride copolymer exceeds 20% by weight. In this case, the impact resistance of the nanocomposite may decrease due to the excessive amount of the styrene maleic hydride copolymer.

The nanocomposite is melt mixed using a low shear mini-molder or a high shear twin screw extruder, and the obtained mixed resin may be manufactured by injection molding in a mini mold or an injection machine. When the twin screw extruder is used, the high shear force of the twin screw extruder is used. By the montmorillonite is sufficiently peeled off by the nano-structure further proceeds, it is possible to obtain a nanocomposite with improved tensile strength and the like.

Hereinafter, the present invention will be described in more detail with reference to the following examples, but the scope of the present invention is not limited to the examples.

EXAMPLE

Reformation of Montmorillonite

Three types were used, namely pristine montmorillonite (PM), Closite 30B and Closite 15A, a product of Southern Clay Product of the United States, whose polarity was controlled through the modification of montmorillonite. Where PM is unmodified montmorillonite and Closite 30B is a modified organic montmorillonite using methyltallow bis-2-hydroxyethyl quaternary ammonium as an organic agent. Closite 15A is a modified organic montmorillonite product using dimethyl dihydrogenatedtallow quaternary ammonium as an organizing agent. The degree of lipophilicity increases in the order of PM, 30B and 15A.

Preparation of MMT-Polycarbonate / ABS Resin Nanocomposites

Preparation of nanocomposites of polycarbonate / ABS resin and montmorillonite proceeded as follows.

Montmorillonite was placed in a forced hot air dryer to remove moisture. The polycarbonate / ABS resin was also dried in a dryer and then melt mixed with montmorillonite using a low shear minimolder or a high shear twin screw extruder with a cup shaped mixing portion. The mixed resin obtained in the extruder was injection molded in a mini molder or an injection machine. Tensile test and impact resistance test were carried out with this specimen. Tensile strength, tensile modulus and elongation were measured using LR-10K UTM (Lloyd), and Izod impact strength was measured with an impact tester (intrinsic precision). In the impact resistance test, Examples 1 to 18 were used for specimens having a thickness of 1/8 inch, and in Example 19, impact resistance was measured for two specimens using 1/4 inch specimens.

Examples 1 to 6 and Comparative Examples 1 to 2: Preparation of MMT-Polycarbonate / ABS Resin Nanocomposites

Example 1

47% by weight of LG-Dow's PC (PC-300) as polycarbonate, 47% by weight of LG Chem's ABS (HI-121) as ABS, 1% by weight of MMT PM as montmorillonite and polymethyl meta to improve physical properties After mixing 5% by weight of acrylate (PMMA, IG-840 of LG Chemical) with a twin screw extruder, a specimen was made with a mini molder to measure physical properties.

Example 2

Except for the addition of 45% by weight of polycarbonate, 45% by weight of ABS and 5% by weight of montmorillonite MMT PM in Example 1 was carried out in the same manner as in Example 1.

Example 3

Except for adding 1% by weight of montmorillonite MMT 30B in Example 1 was carried out in the same manner as in Example 1.

Example 4

Except for adding 5% by weight of montmorillonite MMT 30B in Example 2 was carried out in the same manner as in Example 2.

Example 5

Except for adding 1% by weight of montmorillonite MMT 15A in Example 1 was carried out in the same manner as in Example 1.

Example 6

Except for adding 5% by weight of montmorillonite MMT 15A in Example 2 was carried out in the same manner as in Example 2.

Comparative Example 1

In Example 1, except that only 50% by weight of polycarbonate and 50% by weight of ABS was carried out in the same manner as in Example 1.

Comparative Example 2

In Example 1, except that only 47.5% by weight of polycarbonate, 47.5% by weight of ABS and 5% by weight of PMMA was added in the same manner as in Example 1.

The measurement results of the physical properties of Examples 1 to 6 and Comparative Examples 1 and 2 are shown in Table 1 below.

Example PC (wt%) ABS (% by weight) PMMA (% by weight) MMT (% by weight) Tensile Strength (N / ㎡) % Elongation Impact resistance strength (㎏㎝ / ㎝) PM 30B 15A Comparative Example 1 50 50 - - - - 49.6 7.0 1.6 Comparative Example 2 47.5 47.5 5 - - - 52.5 6.3 6.5 Example 1 47 47 5 One - - 45.7 3.5 2.9 Example 2 45 45 5 5 - - 33.1 1.0 1.5 Example 3 47 47 5 - One - 51.9 8.7 8.2 Example 4 45 45 5 - 5 - 55.8 5.3 4.9 Example 5 47 47 5 - - One 49.4 12.1 23.6 Example 6 45 45 5 - - 5 51.4 10.1 24.0

As shown in Table 1, the impact strength of Example 5, in which 1 wt% MMT 15A was added, was found to be 23.6 kgcm / cm, which is greater than that of Comparative Example 1, which does not contain PMMA and MMT additives. An increase in width is shown. Example 1 with MMT PM showed little change in impact strength at 2.9 kgcm / cm, while Example 3 with MMT 30B increased slightly to 8.2 kgcm / cm, but the increase was not reached in the case of MMT 15A. I couldn't. The impact strength of Comparative Example 1 of PC / ABS (50/50) was very low, 1.6 kgcm / cm, which was shown to be decomposed to some resins during processing, and MMT 15A was improved by adding MMT 15A. It was judged that there was an effect of preventing the decomposition of the resin during the processing of the resin. In addition, in Examples 2, 4, and 6, in which 5% by weight of MMT was added, the improvement in physical properties was not large compared with Examples 1, 3, and 5, in which 1% by weight of MMT was added. The addition was carried out.

Examples 7-8 and Comparative Examples 3-4: Preparation of MMT-Polycarbonate / ABS Resin Nanocomposites Excluded from High Shear Force

Example 7

99 weight of polycarbonate (LG-Dow's PC300) under low shear in cup-shaped mini-molder to determine the effect of montmorillonite on the physical properties in terms of thermodynamics by excluding the effect of high shear force in twin screw extruder % And 1% by weight of the most effective MMT 15A in Examples 1-6 were melt mixed and then tested by preparing specimens in a minimolder.

Example 8

Except for adding only 99% by weight of ABS (LG Chem, ABS DP-215) and 1% by weight of MMT 15A in Example 7, it was carried out in the same manner as in Example 7.

Comparative Example 3

Except for adding only 100% by weight of polycarbonate in Example 7, it was carried out in the same manner as in Example 7.

[Comparative Example 4]

Except for adding only 100% by weight of ABS in Example 7, it was carried out in the same manner as in Example 7.

The measurement results of the physical properties of Examples 7 and 8 and Comparative Examples 3 and 4 are shown in Table 2 below.

Example PC (wt%) ABS (% by weight) MMT 15A (wt%) Tensile Strength (N / ㎡) % Elongation Tensile Modulus (N / mm2) Impact resistance strength (㎏㎝ / ㎝) Comparative Example 3 100 - - 49.5 93.5 1026 71.5 Example 7 99 - One 47.9 88.9 1098 48.1 Comparative Example 4 - 100 - 12.7 106.5 436.7 45.5 Example 8 - 99 One 12.8 120.5 422.2 47.8

As shown in Table 2, when comparing Example 7 with 99% by weight of polycarbonate and 1% by weight of MMT 15A compared with Comparative Example 3, tensile strength was slightly reduced and impact resistance was reduced, whereas ABS 99% by weight and MMT 15A 1 In Example 8, in which weight% was added, both tensile strength and impact resistance increased slightly compared to Comparative Example 4, and montmorillonite was mainly observed to have a good effect on ABS.

Examples 9 to 15 and Comparative Examples 5 to 7: Composition ratio determination of polycarbonate and ABS

Example 9

Using a mini molder, 74.5% by weight of polycarbonate (LG-Dow, PC-300), 24.5% by weight of ABS (LG Chem, ABS DP-215), and 1% by weight of MMT 15A were mixed and the specimens were molded to investigate their properties. It was.

Example 10

Example 9 was carried out in the same manner as in Example 9, except that 74 wt% of polycarbonate, 20 wt% of ABS, 5 wt% of PMMA, and 1 wt% of MMT 15A were mixed.

Example 11

Example 9 was carried out in the same manner as in Example 9, except that 49.5% by weight of polycarbonate, 49.5% by weight of ABS, and 1% by weight of MMT 15A were mixed.

Example 12

Example 9 was carried out in the same manner as in Example 9, except that 47.5% by weight of polycarbonate, 47.5% by weight of ABS, and 5% by weight of MMT 15A were mixed.

Example 13

Example 9 was carried out in the same manner as in Example 9, except that 47 wt% of polycarbonate, 47 wt% of ABS, 5 wt% of PMMA, and 1 wt% of MMT 15A were mixed.

Example 14

Example 9 was carried out in the same manner as in Example 9, except that 34.5% by weight of polycarbonate, 64.5% by weight of ABS, and 1% by weight of MMT 15A were mixed.

Example 15

Example 9 was carried out in the same manner as in Example 9, except that 35 wt% of polycarbonate, 60 wt% of ABS, 4 wt% of PMMA, and 1 wt% of MMT 15A were mixed.

[Comparative Example 5]

Example 9 was carried out in the same manner as in Example 9, except that only 75% by weight of polycarbonate and 25% by weight of ABS were mixed.

Comparative Example 6

In Comparative Example 5, except that only 50% by weight of polycarbonate and 50% by weight of ABS was carried out in the same manner as in Comparative Example 5.

Comparative Example 7

In Comparative Example 5 was carried out in the same manner as in Comparative Example 5 except that only 35% by weight of polycarbonate and 65% by weight of ABS.

Physical property measurement results of Examples 9 to 15 and Comparative Examples 5 to 7 are shown in Table 3 below.

Example PC (wt%) ABS (% by weight) PMMA (% by weight) MMT 15A (wt%) Tensile Strength (N / ㎡) % Elongation Tensile Modulus (N / mm2) Impact resistance strength (㎏㎝ / ㎝) Comparative Example 5 75 25 - - 38.2 88.2 951.7 58.0 Example 9 74.5 24.5 - One 32.8 109.3 820.8 48.9 Example 10 74 20 5 One 34.2 99.7 968.5 44.6 Comparative Example 6 50 50 - - 26.1 117.9 684.7 46.9 Example 11 49.5 49.5 - One 24.6 90.5 742.1 50.8 Example 12 47.5 47.5 - 5 36.7 77.4 888.2 43.9 Example 13 47 47 5 One 34.2 82.9 900.0 40.6 Comparative Example 7 35 65 - - 15.6 46.2 602.6 34.9 Example 14 34.5 64.5 - One 25.2 57.2 633.5 36.1 Example 15 35 60 4 One 21.7 43.2 549.9 36.5

As shown in Table 3, compared with Comparative Example 5 of PC / ABS (75/25) having a high polycarbonate content and Example 9 having 1% by weight of MMT 15A, tensile strength and impact resistance were decreased. In Example 10, where 5% by weight of ABS was replaced with PMMA, tensile strength was increased compared to Example 9, in which only 1% by weight of MMT 15A was added. However, when comparing Comparative Example 6 of PC / ABS (50/50) with Example 11 added with 1% by weight of MMT 15A, the tensile strength decreased slightly, but the impact resistance increased. In addition, in Example 12, in which 5% by weight of MMT 15A was added, tensile strength and tensile modulus were greatly increased, indicating that MMT 15A was effective. In Example 13, in which 5% by weight of PMMA and 1% by weight of MMT 15A were added at the same time, the tensile strength increased to 34.2N / mm 2 compared to 24.6N / mm 2 of Example 11, in which only 1% by weight of MMT 15A was added. It was shown to be effective in increasing strength. This result was similar for PC / ABS (75/25). When the PC content is 35% by weight and the ABS content is 65% by weight, the ABS content is high, and MMT 15A 1% by weight shows the results of Example 14, in which both tensile strength, tensile modulus, elongation, and impact resistance are increased compared to Comparative Example 7. Indicated. In particular, the tensile strength increased greatly from 15.6N / mm 2 to 25.2N / mm 2. In the case of Example 15, in which 4 wt% of PMMA was added at the same time, the impact strength was almost similar, but the tensile strength was slightly decreased compared to the case where only 1 wt% of MMT 15A was added. Therefore, PMMA was found to be mainly effective when the PC content is high because it is determined to increase the tensile strength mainly by acting on the PC.

Examples 16 to 18 and Comparative Examples 8 to 10: Preparation of MMT-polycarbonate / ABS resin nanocomposite with improved heat resistance

Example 16

The effect of MMT 15A was examined for the case where 10% by weight of polyphenylene oxide (PPO) and styrene maleic hydride copolymer (SMA) were added to PC / ABS (50/50). SMA used SMA8 having 8% by weight of MA and SMA14 having 14% by weight of MA.

Using a mini molder, 49.5% by weight of polycarbonate (LG-Dow, PC-300), 49.5% by weight of ABS (LG Chemical, ABS DP-215), and 1% by weight of MMT 15A were mixed and the specimens were molded to investigate their properties. It was.

Example 17

Example 16 was the same as in Example 16 except for mixing 39.5% by weight of polycarbonate, 39.5% by weight ABS, 10% by weight SMA14, 10% by weight PPO and 1% by weight MMT 15A.

Example 18

Example 17 was carried out in the same manner as in Example 17, except that SMA8 10% by weight instead of SMA14.

Comparative Example 8

Except that in Example 16, only 50% by weight of polycarbonate and 50% by weight of ABS was carried out in the same manner as in Example 16.

Comparative Example 9

Example 16 was the same as in Example 16 except for mixing 40% by weight of polycarbonate, 40% by weight ABS, 10% by weight SMA14 and 10% by weight PPO.

Comparative Example 10

Comparative Example 9 was carried out in the same manner as in Comparative Example 9 except that SMA8 10% by weight instead of SMA14.

The measurement results of the physical properties of Examples 16 to 18 and Comparative Examples 8 to 10 are shown in Table 4 below.

Example PC (wt%) ABS (% by weight) SMA14 (wt%) SMA8 (wt%) PPO (% by weight) MMT 15A (wt%) Tensile Strength (N / ㎡) % Elongation Tensile Modulus (N / mm2) Impact resistance strength (㎏㎝ / ㎝) Comparative Example 8 50 50 - - - - 26.1 117.9 684.7 46.9 Example 16 49.5 49.5 - - - One 24.6 90.5 742.1 50.8 Comparative Example 9 40 40 10 - 10 - 22.9 8.7 729.7 12.6 Example 17 39.5 39.5 10 - 10 One 25.8 4.9 793.4 14.8 Comparative Example 10 40 40 - 10 10 - 30.0 8.6 793.0 12.6 Example 18 39.5 39.5 - 10 10 One 33.5 6.7 1009 14.4

As shown in Table 4, when PPO and SMA14 were added, there was no significant change in tensile strength, but when PPO and SMA8 were added, the tensile strength increased to 30.0 N / mm 2. In other words, SMA was found to be more effective than SMA14. In addition, when PPO and SMA8 were added, Example 18, in which 1% by weight of MMT 15A was further added, compared to Comparative Example 10 in which MMT 15A was not added, the tensile strength was further increased from 30.0 N / mm 2 to 33.5 N / mm 2. The impact strength was increased from 12.6kgcm / cm to 14.4kgcm / cm, and the tensile modulus was 1,009N / mm 2, more than 25% higher than 793.0N / mm 2 without MMT 15A. It was observed that the effect by the addition of 1% by weight of the inorganic substance was a very remarkable effect.

Example 19 and Comparative Examples 11 to 12: Effect of the processing method on the physical properties of the nanocomposite

Example 19

In order to determine the effect of the processing method on the properties of PC / ABS including MMT 15A, mixing 49.5% by weight of PC, 49.5% by weight of ABS and 1% by weight of MMT 15A in a twin-screw extruder was carried out. saw. Impact resistance was measured using 1/4 inch and 1/8 inch specimens.

Comparative Example 11

Example 19 was carried out in the same manner as in Example 19, except that only 100 wt% of PC was added.

Comparative Example 12

Example 19 was carried out in the same manner as in Example 19, except that only 50% by weight of PC and 50% by weight of ABS were added.

The measurement results of the physical properties of Example 19 and Comparative Examples 11 to 12 are shown in Table 5 below.

Example / Comparative Example Comparative Example 11 Comparative Example 12 Example 19 PC (wt%) 100 50 49.5 ABS (% by weight) - 50 49.5 MMT 15A (wt%) - - One Impact Strength (1/4 ") (kgcm / cm) 12.3 48.2 27.9 Impact Strength (1/8 ") (kgcm / cm) 74.6 64.2 82.9 Heat Deflection Temperature (℃) 129 100.4 102.6 Tensile Strength (N / ㎡) 72 47.9 46.8 % Elongation 150 61.4 89.1 Flexural Strength (N / ㎡) 103 80.4 80 Rockwell Hardness 121.7 106.3 106.7

As shown in Table 5, the impact resistance of the specimen mixed with 1% by weight of MMT 15A in PC / ABS (50/50) was reduced from 48.2kgcm / cm to 27.9kgcm / cm in the 1 / 4inch specimen test. However, in the 1/8 inch specimen test, it increased from 64.2kgcm / cm to 82.9kgcm / cm. This is higher than both pure PCs, showing a shock resistance similar to that of pure PCs. In other words, it is very encouraging because it can be obtained by adding only 1% by weight of MMT 15A to PC / ABS, which is similar to PC but higher than PC. In general, when the inorganic material is added, the tensile modulus increases, but the tensile strength and the impact resistance decrease, which may prove the nano-effect of MMT 15A. In FIG. 1, when the fracture surface of the impact resistant specimen was observed with a transmission electron microscope (TEM), it can be seen that MMT is dispersed in nanoscale.

When 1% by weight of 15A in MMT is added to the PC / ABS resin, a composition having improved tensile strength and impact resistance strength may be obtained. In particular, it is a very effective result to increase the tensile strength and impact strength at the same time by the addition of inorganic materials. In order to further increase the tensile strength, PMMA must be added at the same time, and when heat resistance is also considered, SMA14 and MMT 15A containing 14% of PPO and MA should be added simultaneously.

As described above, the polycarbonate / ABS resin nanocomposite including montmorillonite according to the present invention increases tensile modulus when inorganic materials are added, but unlike general tendency to decrease tensile strength and impact strength, tensile strength and impact resistance Strength is greatly improved, and when PMMA, PPO, SMA is further added, it is a useful invention that can be actively utilized in various products of electric and electronics by further improving physical properties such as tensile strength and heat resistance.

Although the present invention has been described in detail with reference to the described embodiments, it will be apparent to those skilled in the art that various modifications and variations are possible within the scope and spirit of the present invention, and such modifications and modifications belong to the appended claims. It is also natural.

1 is a photograph of the fracture surface of the impact resistant specimen of the PC / ABS resin nanocomposite according to an embodiment of the present invention by transmission electron microscope.

Claims (8)

Montmorillonite, and nanocomposites comprising a polycarbonate and acrylonitrile butadiene styrene copolymer resin. The method of claim 1, The montmorillonite is a nanocomposite, characterized in that the organically modified montmorillonite. The nanocomposite of claim 2, wherein the montmorillonite is modified montmorillonite organicized with a quaternary ammonium salt. The method of claim 1, The montmorillonite is nanocomposite, characterized in that added to 0.1 to 20% by weight based on the entire nanocomposite. The method of claim 1, The polycarbonate is added to 20 to 58% by weight based on the entire nanocomposite, the acrylonitrile butadiene styrene resin is added to the nanocomposite, characterized in that added to 40 to 70% by weight. The method of claim 1, The nanocomposite further comprises at least one additive selected from the group consisting of polymethyl methacrylate, polyphenylene oxide and styrene maleic hydride copolymer. The method of claim 6, The nanocomposite is polymethyl methacrylate is added in 1 to 30% by weight based on the entire nanocomposite, the polyphenylene oxide is added in 1 to 20% by weight, the styrene maleic hydride copolymer is 1 to Nanocomposite, characterized in that added to 20% by weight. The method of claim 1, The nanocomposite is a nanocomposite, characterized in that the melt mixed using a twin screw extruder.