KR101188924B1

KR101188924B1 - Polypropylene composition with a excellent transparency and improved processing window, and the devices including articles

Info

Publication number: KR101188924B1
Application number: KR20100099411A
Authority: KR
Inventors: 강귀성; 이현섭
Original assignee: 호남석유화학 주식회사
Priority date: 2010-10-12
Filing date: 2010-10-12
Publication date: 2012-10-08
Also published as: KR20120037761A

Abstract

The present invention relates to a polypropylene resin composition, by combining two or more sorbitol-based nucleating agents in an ethylene-propylene random copolymer and adjusting the composition ratio, polypropylene resin with excellent transparency and processability in a wide range of temperature The composition can be provided, and transparent food containers, sheets, films, and stationery products including such polypropylene resin compositions can be provided.

Description

POLYPROPYLENE COMPOSITION WITH A EXCELLENT TRANSPARENCY AND IMPROVED PROCESSING WINDOW, AND THE DEVICES INCLUDING ARTICLES}

The present invention relates to a polypropylene resin composition, and more particularly, to a polypropylene resin composition having excellent transparency and processability including an ethylene-propylene random copolymer.

In general, polypropylene resin is a material widely used in automobile parts, home appliances, food containers, household goods, etc. due to its excellent moldability, rigidity, and chemical resistance. These polypropylene resins are classified into homo polypropylene, ethylene-propylene random copolymers, and ethylene-propylene block copolymers. Among them, ethylene-propylene random copolymers have excellent transparency, and thus, transparency of food containers, films, sheets, etc. Widely used in the required product. In the case of the homo polypropylene resin, it is characterized by high rigidity, but it is inferior in impact resistance, low in transparency, and narrow in molding temperature, which is not suitable for a transparent container material, and in the case of ethylene-propylene block copolymer, low temperature impact resistance It is characterized by high, but low transparency and a drop in impact impact whitening occurs.

Korean Patent Laid-Open No. 2001-0006497 discloses a method of controlling the melt flow rate ratio and the intrinsic viscosity ratio of an olefin copolymer, a homopolymer, and an ethylene-propylene copolymer. There is a problem that is difficult to apply for thick products.

On the other hand, Korean Patent Laid-Open Publication No. 2009-0057617 proposes a method for producing highly transparent polypropylene by increasing the dispersibility of vinyl cyclic saturated hydrocarbon, but catalyst development should be prioritized and a polymerization process should be added. There is a problem that is difficult to apply.

Accordingly, the present invention has been made to solve the above problems, to provide a polypropylene resin composition excellent in transparency and processability at a wide range of temperature and a product comprising the same.

According to an aspect of the present invention,

(3) 100 parts by weight of polypropylene resin composed of ethylene-propylene random copolymer; And 0.1 to 0.3 parts by weight of a nucleating agent, wherein the ethylene-propylene random copolymer has an ethylene content of 1 to 6 parts by weight and a melt index of 14 to 22 g / 10 min, based on 100 parts by weight of the copolymer, Nucleating agents 1,3: 2,4-bis (3,4-dimethyldibenzylidene) sorbitol (1,3: 2,4-Bis (3,4-dimethyldibenzylidene) Sorbitol), bis (p-methyldibenzylidene ) Or two or more of Bis (p-methyldibenzylidene) Sorbitol and Substituted Dibenzylidene Sorbitol (substituted Dibenzylidene Sorbitol) are combined to provide a polypropylene resin composition that can be molded at a molding temperature of 190 ° C to 250 ° C.

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(4) The polypropylene resin composition according to the above (3), wherein the transparency of the 1 mm thick haze specimen produced at a molding temperature of 190 ° C. to 250 ° C. is 16% or less, and the 2 mm thick haze is HAZE. It provides a polypropylene resin composition, characterized in that the transparency of the specimen is 30% or less.

The present invention to solve the above another problem,

(5) It provides the product containing the polypropylene resin composition as described in said (3) or (4).

(6) The product according to (5), wherein the product is a transparent food container, sheet, film or stationery product.
Moreover, in order to solve the said subject,
100 parts by weight of a polypropylene resin consisting of an ethylene-propylene random copolymer; And 0.1 to 0.3 parts by weight of a nucleating agent, wherein the ethylene-propylene random copolymer has an ethylene content of 1 to 6 parts by weight and a melt index of 14 to 22 g / 10 min, based on 100 parts by weight of the copolymer, Nucleating agents 1,3: 2,4-bis (3,4-dimethyldibenzylidene) sorbitol (1,3: 2,4-Bis (3,4-dimethyldibenzylidene) Sorbitol), bis (p-methyldibenzylidene ) Is a polypropylene resin composition in which two or more of sorbitol (Bis (p-methyldibenzylidene) Sorbitol) and substituted Dibenzylidine Sorbitol (M) are combined to be molded at a molding temperature of 190 ° C to 210 ° C, and the polypropylene resin The composition is polypropylene, characterized in that the transparency of the 1 mm thick haze specimen produced at the molding temperature 190 ℃ ~ 210 ℃ less than 14%, the transparency of the 2 mm thick haze specimen is less than 29% It provides a resin composition.

According to the present invention, by combining two or more sorbitol-based nucleating agent to the ethylene-propylene random copolymer and adjusting the composition ratio, it is possible to provide a polypropylene resin composition excellent in transparency and processability in a wide range of temperature. In addition, it is possible to provide a transparent food container, sheet, film and stationery products comprising such a polypropylene resin composition.

Hereinafter, the present invention will be described in detail with reference to preferred embodiments. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims and their equivalents. It is to be understood that various equivalents and modifications may be substituted for those at the time of the present application.

The present invention is 100 parts by weight of ethylene-propylene random copolymer; And 0.1 to 0.3 parts by weight of nucleating agent, wherein the nucleating agent provides a polypropylene resin composition characterized in that the combination of two or more sorbitol-based nucleating agent.

The ethylene-propylene random copolymer is a propylene copolymer composed mainly of propylene. For example, propylene and ethylene are simultaneously introduced into a polymerization reactor, and then triethyl aluminum, a Dicer catalyst, and a silane-based electron donor are injected. Under the reaction temperature of 65-75 ° C. and 32-35 K / G atmosphere, the slurry can be prepared by bulk polymerization, and the melt index can be controlled by hydrogen. The polymerization reactor can be made of any one of a combination of loop, loop and gas phase reactors. On the other hand, using the Dicer catalyst as the catalyst can be expected to improve the physical properties of the ethylene-propylene random copolymer, but is not limited to this Ziegler-Natta catalyst, metallocene catalyst can also be used.

The ethylene content of the ethylene-propylene random copolymer is preferably contained 1 to 6 parts by weight, more preferably 2 to 4 parts by weight in 100 parts by weight of the copolymer. When the ethylene content is less than 1 part by weight, transparency is low, and when it exceeds 6 parts by weight, it is unsuitable as a material for a container used in daily life, such as a decrease in rigidity and heat resistance. On the other hand, the melt index of the ethylene-propylene random copolymer is preferably 14 ~ 22g / 10min. When the melt index is less than 14g / 10min, extrusion and injection processability is not good, and when the melt index is more than 22g / 10min, the impact strength is insufficient, which is not preferable.

The nucleating agent produces a smaller crystal size of the nucleus in the polypropylene, and in particular, improves transparency by reducing the scattered light. 1,3: 2,4-bis (3,4-dimethyldibenzylidene) sorbitol (1,3: 2,4-Bis (3,4-dimethyldibenzylidene) nucleating agent is mainly used in the technical field to which this invention belongs. In this case, in order to obtain a polypropylene composition having excellent transparency using the sorbitol-based nucleating agent, injection and extrusion should be performed at a high temperature of about 230 ° C. because the melting temperature of the nucleating agent is high. In the case of combining the nucleating agent and using the optimum composition ratio, it is found that the nucleating agent is increased even at a low temperature unlike the sorbitol-based nucleating agent alone, and the poly is excellent in a wide range of temperature including the low temperature. It has been found that the propylene resin composition can be provided.

Here, the sorbitol-based nucleating agent may be used in combination of two or more sorbitol-based nucleating agents generally used, 1,3: 2,4-bis (3,4-dimethyldibenzylidene) sorbitol (1,3: 2, A combination of two or more of 4-Bis (3,4-dimethyldibenzylidene) Sorbitol, bis (p-methyldibenzylidene) Sorbitol (Bis (p-methyldibenzylidene) Sorbitol) and substituted Subbendyl Dibenzylidene Sorbitol desirable.

The composition ratio of the nucleating agent is preferably 0.1 to 0.3 parts by weight, more preferably 0.15 to 0.25 parts by weight, and most preferably 0.18 to 0.22 parts by weight based on 100 parts by weight of the ethylene-propylene random copolymer. When the composition ratio of the nucleating agent is less than 0.1 parts by weight, it is difficult to secure sufficient transparency. When the content of the nucleating agent is more than 0.3 parts by weight, the transparency improvement effect is not proportional to the amount added, which is not efficient.

On the other hand, the polypropylene resin composition according to the present invention may be additionally added various additives such as neutralizers, antioxidants, slip agents, weathering stabilizers, antistatic agents, pigments and the like commonly used.

Hereinafter, preferred examples for better understanding of the present invention are shown together with comparative examples.

First, the physical property measurement method of the polypropylene resin composition according to the Examples and Comparative Examples of the present invention is as follows.

1) Melt index: measured at a temperature of 230 ° C. and a load of 2.16 kg based on ASTM D1238DP.

2) Flexural modulus: measured at 23 ° C. and 50% RH based on ASTM D790.

3) IZOD impact strength: measured at 23 ° C. and 50% RH based on ASTM D256.

4) Transparency (HAZE): Transparency (HAZE) was measured according to ASTM D1003. Transparency by thickness (1mm, 2mm), molding temperature (190 ℃, 210 ℃, 230 ℃, 250 ℃) Was measured. Transparency indicates that the lower the HAZE value, the better.

Comparative example One

100 parts by weight of an ethylene-propylene random copolymer containing 3.5 parts by weight of ethylene, a melt index of 14 to 22 g / 10 min, and a density of 0.88 to 0.92 g / cm 3, 1,3: 2,4-bis (3,4-dimethyl Dibenzylidine) 0.2 parts by weight of sorbitol, 0.05 parts by weight of neutralizing agent, 0.2 parts by weight of antioxidant and 0.04 parts by weight of antistatic agent were kneaded in a Henschel mixer for 3 minutes, and then extruded with a twin screw extruder of 180 to 210 ° C. with a diameter of 1.5 to 2 mm. The pelletized composition was obtained. In order to measure the physical properties and transparency of the prepared pellets, each specimen was prepared using a Dongshin emulsifying 150-ton molding machine (PRO-150WD), and then physical properties and transparency were measured.

The evaluation results of the physical properties of the prepared specimens are shown in Table 2, and the results of the transparency evaluation of the 1 mm thick HAZE specimens prepared for each molding temperature are shown in Table 3. The results are shown in Table 4.

Comparative example 2 to 7, Example 1 to 6

As shown in Table 1, the composition was prepared in the same manner as in Comparative Example 1 in addition to adjusting the composition and the composition ratio of the nucleating agent a to e, after preparing the specimen in the same manner as in Comparative Example 1, physical properties and transparency Was measured.

division
Nuclear agent a b c d e system Comparative Example 1 0.2 - - - - 0.2 Comparative Example 2 - 0.2 - - - 0.2 Comparative Example 3 - - 0.2 - - 0.2 Example 1 0.16 0.04 - - - 0.2 Example 2 0.14 0.06 - - - 0.2 Example 3 0.1 0.1 - - - 0.2 Example 4 0.16 - 0.04 - - 0.2 Example 5 0.14 - 0.06 - - 0.2 Example 6 0.1 - 0.1 - - 0.2 Comparative Example 4 0.18 - - 0.02 - 0.2 Comparative Example 5 0.16 - - 0.04 - 0.2 Comparative Example 6 0.18 - - - 0.02 0.2 Comparative Example 7 0.16 - - - 0.04 0.2 (week)
a: 1,3: 2,4-Bis (3,4-dimethyldibenzylidene) Sorbitol
b: Bis (p-methyldibenzylidene) Sorbitol
c: Substituted Dibenzylidene Sorbitol
d: Phosphate ester compound
e: Aluminum or hydroxybis [2,4,8,10-tetrakis (1,1-dimethylethyl) -6-hydroxy-12H-dibenzo (d, g)-(1,3,2) dioxaphosphocin-6-oxidato]

division Melt Index
(g / 10 min) Flexural modulus
(Kg / cm2) Izod impact strength
(Kg? Cm / cm) Comparative Example 1 16.6 12900 5.2 Comparative Example 2 16.9 12500 4.8 Comparative Example 3 17.2 12300 4.9 Example 1 17.5 13400 4.9 Example 2 16.8 12500 5.0 Example 3 16.8 12100 4.9 Example 4 16.7 12900 4.9 Example 5 16.1 12500 4.9 Example 6 17.6 12600 4.9 Comparative Example 4 16.8 13100 4.8 Comparative Example 5 16.8 12300 5.1 Comparative Example 6 17.3 12500 4.8 Comparative Example 7 16.8 12600 5.1

division Transparency by Molding Temperature (HAZE) (%) 190 ℃ 210 ℃ 230 ℃ 250 ℃ Comparative Example 1 13.76 9.78 11.00 9.28 Comparative Example 2 15.26 11.26 11.78 10.46 Comparative Example 3 13.86 11.72 11.30 10.38 Example 1 13.00 10.90 9.72 9.06 Example 2 12.88 10.52 9.68 9.32 Example 3 12.72 10.34 9.38 9.00 Example 4 13.32 10.70 9.44 9.04 Example 5 12.82 10.04 9.40 8.68 Example 6 10.52 9.02 9.20 8.52 Comparative Example 4 12.70 10.14 11.22 10.04 Comparative Example 5 14.52 13.34 12.88 12.84 Comparative Example 6 12.30 11.56 11.78 9.74 Comparative Example 7 11.86 12.28 12.68 13.20

division
Transparency by Molding Temperature (HAZE) (%) 190 ℃ 210 ℃ 230 ℃ 250 ℃ Comparative Example 1 29.68 22.66 19.34 20.16 Comparative Example 2 29.62 23.50 22.64 22.76 Comparative Example 3 28.48 20.10 19.60 20.12 Example 1 27.74 22.94 20.40 19.98 Example 2 27.62 21.98 21.24 22.82 Example 3 27.68 21.20 20.94 20.72 Example 4 28.64 23.38 20.50 20.30 Example 5 27.76 21.42 20.44 20.34 Example 6 22.30 20.56 19.72 19.66 Comparative Example 4 27.20 23.80 24.58 21.18 Comparative Example 5 31.02 27.60 25.60 25.54 Comparative Example 6 26.34 26.12 22.02 22.68 Comparative Example 7 27.52 25.16 25.92 26.24

As shown in Table 3 and Table 4, when comparing Examples 1 to 6 and Comparative Examples 1 to 3, transparency when using two or more in combination as compared to the case of using sorbitol-based nucleating agents a to c alone It can be seen that it is excellent in this wide temperature range. On the other hand, as shown in Table 2, the flexural modulus, Izod impact strength can be seen to maintain the same level.

In addition, when comparing the results of the transparency measurement of Comparative Examples 4 to 7 shown in Table 3 and Table 4, when the nucleating agent contains a nucleating agent other than the sorbitol-based nucleating agent is equivalent to or rather insufficient when used as a sorbitol-based nucleating agent alone, It can be seen that by using only two sorbitol-based nucleating agents in combination, it is possible to provide a polypropylene resin composition having the best transparency while maintaining good physical properties.

Claims

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100 parts by weight of a polypropylene resin consisting of an ethylene-propylene random copolymer; And
0.1 to 0.3 parts by weight of nucleating agent;
The ethylene-propylene random copolymer has an ethylene content of 1 to 6 parts by weight and a melt index of 14 to 22 g / 10 min based on 100 parts by weight of the copolymer, and the nucleating agent is 1,3: 2,4-bis ( 3,4-dimethyldibenzylidine) sorbitol (1,3: 2,4-Bis (3,4-dimethyldibenzylidene) Sorbitol), bis (p-methyldibenzylidene) sorbitol (Bis (p-methyldibenzylidene) Sorbitol) and A polypropylene resin composition which can be molded at a molding temperature of 190 ° C to 250 ° C by combining at least two of substituted Dibenzylidene Sorbitol.

The method of claim 3,
The polypropylene resin composition has a transparency of 16 mm or less of a 1 mm thick haze specimen prepared at a molding temperature of 190 ° C. to 250 ° C., and a transparency of a 2 mm thick haze specimen of 30% or less. Polypropylene resin composition.

An article comprising the polypropylene resin composition according to claim 3.

The method of claim 5,
The product is a product characterized in that the transparent food container, sheet, film or stationery products.

100 parts by weight of a polypropylene resin consisting of an ethylene-propylene random copolymer; And
0.1 to 0.3 parts by weight of nucleating agent;
The ethylene-propylene random copolymer has an ethylene content of 1 to 6 parts by weight and a melt index of 14 to 22 g / 10 min based on 100 parts by weight of the copolymer, and the nucleating agent is 1,3: 2,4-bis ( 3,4-dimethyldibenzylidine) sorbitol (1,3: 2,4-Bis (3,4-dimethyldibenzylidene) Sorbitol), bis (p-methyldibenzylidene) sorbitol (Bis (p-methyldibenzylidene) Sorbitol) and It is a polypropylene resin composition which can be molded at a molding temperature of 190 ° C to 210 ° C by combining two or more of substituted Dibenzylidene Sorbitol.
The polypropylene resin composition has a transparency of less than 14% of a 1 mm thick HAZE specimen prepared at the molding temperature of 190 ° C. to 210 ° C., and a transparency of a 2 mm thick haze specimen of less than 29%. Polypropylene resin composition.