KR20010096430A - Polyolefin resin composition having a matt property, and a matt film using it - Google Patents

Abstract

PURPOSE: A flat polyolefin resin composition and a flat film prepared by using the composition are provided, to reduce the gloss of a film by the scattered reflection of light by forming fine irregularities on the surface of a film, to improve the impact strength and to allow the film to be prepared by inflation film-forming method. CONSTITUTION: The flat polyolefin resin composition comprises 50-95 wt% of a homopolypropylene with the melting index of 20 dg/min or less, or a random polypropylene resin containing ethylene and/or 1-butene; and 5-50 wt% of a copolymer of an alpha-olefin of C3-C10 with the melting index of 1.0 dg/min or less and the density of 0.919-0.970 g/cm3 and ethylene, or polyethylene resin. Optionally the composition comprises further 0.0001-1 wt% of silica with the average particle size of 10 micrometers or less; 0.0001-1 wt% of an organic slipping agent selected from the group consisting of oleamide, erucamide and their mixture; and/or 0.0001-1 wt% of a destaticizing agent. Also optionally the composition comprises further 5-30 wt% of one polymer selected from the group consisting of an ethylene-propylene copolymer containing 30-80 wt% of ethylene with the melting index of 1.0 dg/min or less, an ethylene-propylene-diene copolymer and ethylene vinyl acetate containing 70 wt% of ethylene or more with the melting index of 1.0 dg/min or less; and 10-300 ppm of peroxides. The flat film is prepared by the inflation film forming method of the resin composition.

Description

Polyolefin resin composition having a matte property and a matte film prepared using the same {Polyolefin resin composition having a matt property, and a matt film using it}

The present invention relates to a polyolefin resin composition having a matte property and a matte film prepared using the same, and more particularly, a polyolefin resin composition having a matte property and impact strength, which can be manufactured by an inflation film molding method, and inflation thereof It relates to a matte film produced using a film forming method.

In recent years, matt films, which have a low surface gloss and impart a soft touch to the film to enhance the merchandise of the packaged material, are widely used as high value-added products. Manufacture.

Matte development is caused by the diffuse reflection phenomenon by the unevenness | corrugation of a reflective surface, and the method described below can be used in order to provide a matte characteristic to the surface of a film.

First, the surface treatment of the surface of the general film by a method such as coating and etching,

Secondly, a method using the flowability, shrinkage and refractive index difference between the mixed resins, which is characteristic of the resin mixture having incompatibility;

Third, a method of applying unevenness to the surface by using inorganic materials, and

Fourth, the embossing process by giving unevenness to the cooling roll.

In general, the first method requires separate post-processing equipment such as coating and drying equipment, and the second, third, and fourth methods, and a mixing method thereof, are used for the casting film.

In addition, the polyolefin film may be prepared by a casting molding method using a straight die (T-die), a blown film molding method using a round die, and an inflation film molding method.

However, since the casting method generally requires a stretching process, there is a limit in that the processing stability in the stretching process must be a certain level or more, and the blown film forming method manufactures a film through stretching of a bubble. There is a limit that the bubble stability of the resin to be used is a certain level or more. On the other hand, the inflation film forming method does not require the stretching process, the bubble stability is relatively good, and the processing machine is also relatively inexpensive compared to other methods.

US Pat. No. 5,560,885 describes a resin composition having matt properties and a molding technique thereof using a polyolefin mixture. According to the contents disclosed in the patent, the resin composition uses an incompatible ethylene-alpha olefin copolymer and propylene-alpha olefin copolymer or a terpolymer blend thereof, and the processing method of the molding technique is sheet production by casting. Thereafter, a biaxial stretching method is used, wherein the stretching temperature is 40 to 100 ° C. and the stretching ratio is 32 to 70 times. In addition, MI (melt index) of resin to be used is 1.5 g / min-12 g / min, Preferably it is known as 2.5-6 g / min.

In addition, U. S. Patent No. 5,473, 016 describes a resin composition capable of producing a film or sheet having matt properties, such a resin mixture comprising: 1) 10 to 80% by weight of a polyolefin copolymer having a MI of 1 to 20 g / min, 2) 5-30% by weight of a super low density ethylene-alphaolefin copolymer having a density of 0.86-0.91 g / cm ³ , and 3) 5-85% by weight of a modified polyolefin resin having a MI of 0.1-2.0 g / 10min. , The film is produced by the casting method.

Film produced by the casting method can be seen through the conventional literature, due to the effect of uniaxial or biaxial stretching, has a disadvantage of weak tear strength and impact strength, the process is complicated and the initial investment costs a lot of disadvantages, casting The film produced by the method has a disadvantage in that a second sealing process is required when manufacturing a packaging bag such as a shopping bag.

In addition, U.S. Patent No. 3,361,704 describes a method of adding matte properties to a polyolefin film by adding an inorganic material. In the case of adding 30 to 80% of an inorganic material, there is a phenomenon of deterioration of physical properties due to an inorganic material having no compatibility with a resin. By appearing, tearing, tensile strength, impact strength is lowered, there is a problem that requires a separate (compounding) equipment for mixing the inorganic material.

On the other hand, there is no example produced by the inflation film molding method in producing a matte film. In order to use the inflation molding method, the melt index is in the range of 8 to 12, but the melt index of the matte film produced in the conventional straight die is very low compared to the above-mentioned value, which causes a problem in production.

Accordingly, the present inventors have studied and researched to solve the above-mentioned problems. As a result, the inventors have found a polyolefin resin composition having a matte property consisting of a polypropylene resin, an incompatible polyethylene resin, an antiblocking agent, and the like. It became.

Accordingly, an object of the present invention is to solve the problems of the prior art, using an inflation film forming method having no stretching process, excellent bubble stability, and cheap processing equipment, to produce a matte film having excellent properties such as matte properties and impact strength It is to provide a polyolefin resin composition that can be.

In addition, another object of the present invention to provide a matte film for producing the polyolefin resin composition using an inflation film molding method.

Polyolefin resin composition having a matte properties of the present invention for achieving the above object is 50 to 95% by weight of a random polypropylene resin containing homopolypropylene or ethylene and / or butene-1 having a melt index of 20 dg / min or less; It has a melt index of 1.0 dg / min or less, a density of 0.919 to 0.970 g / cm ³ , and a copolymer of alpha to olefins having 3 to 10 carbon atoms and ethylene or 5 to 50 wt% of ethylene homopolymerized resin.

Matte film of the present invention for achieving the above another object, 50 to 95% by weight of a random polypropylene resin comprising homo polypropylene or ethylene and / or butene-1 having a melt index of 20 dg / min or less; Polyolefin having a matte characteristic, having a melt index of less than 1.0 dg / min, a density of 0.919 to 0.970 g / cm ³ , and a copolymer of alpha to ethylene having 3 to 10 carbon atoms or 5 to 50 wt% of ethylene homopolymerized resin. The resin composition is prepared using the inflation film molding method.

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

As described above, the composition according to the present invention comprises 50 to 95% by weight of a random polypropylene resin (first component) comprising homo polypropylene or ethylene and / or butene-1 having a melt index of 20 dg / min or less; It has a melt index of 1.0 dg / min or less, a density of 0.919 to 0.970 g / cm ³ , and a copolymer of alpha olefin and ethylene having 3 to 10 carbon atoms or 5 to 50% by weight of ethylene homopolymerized resin (second component). And, optionally, 0.0001 to 1% by weight of an organic slip agent selected from the group consisting of silica (SiO ₂ ) having a mean particle size of 10 μm or less (third component), oleamide, erucamide, and mixtures thereof (4th component) and / or 0.0001-1 weight% (5th component) of antistatic agent are further included.

In addition, the composition according to the present invention is an ethylene-propylene copolymer (EPR), ethylene-propylene-diene terpolymer (EPDM) and melt index comprising 30 to 80% by weight of ethylene having a melt index of 1.0 dg / min or less 5-30% by weight of one polymer selected from the group consisting of ethylene vinyl acetate (EVA) containing 70% by weight or more of ethylene of 1.0 dg / min or less, and 10 to 300 ppm of the peroxide (seventh component). Optionally included.

In the resin mixture, the first component constituting the matrix phase is selected from a homopolypropylene resin having a melt index (ASTM D1238) of 20 dg / min or less or a random polypropylene resin containing ethylene and / or butene-1. The resin is 50 to 95% by weight, the melt index is more than 20dg / min, the processability during the production of inflation film is difficult to make the film, the content is less than 50% or more than 95% by weight matt There is a problem that the characteristic disappears, and preferably 60 to 85% by weight.

The second component added to impart unevenness to the film surface due to the difference in refractive index / flow / shrinkage with the first component, which is a matrix resin in a dispersed phase, has a melt index of 1.0dg / min or less and a density of 0.919 to 0.970 g / cm ³ and a copolymer of alpha olefin and ethylene having 3 to 10 carbon atoms or ethylene homopolymer resin, for example, HDPE, LLDPE or LDPE. It is -50 weight%. If the melt index exceeds 1.0dg / min, there is a problem that the matting characteristics disappear, and if the density exceeds 0.0970g / cm ³ , there is a problem that the impact strength and transparency are lowered. In addition, when the content of the second component is less than 5% by weight, the matte properties are reduced, and when the content of the second component exceeds 50% by weight, transparency is reduced.

On the other hand, the matte properties of the resin is primarily because the greater the difference between the melt index of the first component and the second component, the better the matte characteristics due to the phase separation and surface roughness due to the difference in viscosity and flowability.

In addition, 0.0001 to 1% by weight of silica (SiO ₂ ) having an average particle size of 10 μm or less is added as a third component in order to impart opening properties and supplement matt characteristics to the film prepared by using the final inflation film forming method. However, if the average particle size exceeds 10 mu m, the opening properties and the matte properties are good, but there is a problem that the transparency is lowered, and preferably 2 to 7 mu m. In addition, when the content of silica is less than 0.0001% by weight, the opening and matting properties are inferior. When the content of silica is more than 1% by weight, the opening and matting properties are good, but the transparency is lowered. In the case of, there is a tendency to add a relatively large amount compared to the homo polypropylene.

In addition, a fourth component of an organic slip agent selected from the group consisting of oleamide, erucamide, and mixtures thereof to reduce the opening property and the number of friction of the film to give productivity in post-processing When the content of the fourth component is less than 0.0001% by weight of 0.0001 to 1% by weight, the opening of the film is lowered, when the content of more than 1% by weight is eluted to the surface of the film during processing is less matte effect. In addition, the antistatic agent of the fifth component may be added at 0.0001 to 1% by weight in order to prevent static electricity in the composition of the present invention. When the amount of the antistatic agent added is less than 0.0001% by weight, there is almost no effect of addition, and when the amount of the antistatic agent exceeds 1% by weight, the adhesion of the film may be caused by dissolution.

The sixth component, which serves to help the compatibility of the first component and the second component to compensate for mechanical property degradation such as impact strength, which is a general disadvantage of the phase-separated resin, has a melt index of 1.0dg / min or less Ethylene-propylene copolymer (EPR) containing 30 to 80% by weight of ethylene, ethylene-propylene-diene terpolymer (EPDM) and ethylene vinyl including 70% or more by weight of ethylene having a melt index of 1.0 dg / min or less It further comprises 5 to 30% by weight of one polymer selected from the group consisting of acetate and the sixth component provides excellent feel in itself. In this case, if the content of the sixth component is less than 5% by weight, there is almost no additive effect, and if the content of the sixth component exceeds 30% by weight, there is a problem in that the stiffness and matte properties of the film are inferior.

The seventh component, which is a component necessary for controlling the visual feel of the matte film surface to the resin composition, such as acting as a compatibilizer of polypropylene and polyethylene to reduce the size of the phase-separated dendritic phase, thereby imparting a visual characteristic of the soft touch Silver peroxide (Peroxide) more selectively contains 10 to 300ppm, wherein the content of the peroxide is less than 10ppm almost no addition effect, if it exceeds 300ppm there is a possibility of odor and foreign matter generation.

Thus, the processing equipment and processing conditions for producing a polyolefin resin composition having a matte property composed of the first to seventh components into a matte film are used inflation film equipment that is commonly used, the processing conditions are extruded from the die The temperature of resin used is 180-250 degreeC, and the temperature of cooling water shall be less than 30 degreeC. If the temperature of the resin extruded from the die is less than 180 ℃ melt fraction (Melt Fracture) occurs on the film surface and the film surface is not multiplied, if it exceeds 250 ℃ bubble stability is lowered to be impossible to form a uniform film. Moreover, transparency of a film will fall when the temperature of cooling water exceeds 30 degreeC.

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 thereto.

Examples 1-8

The resin composition containing each component according to Table 1 was kneaded at 200 ° C. using a 30ψ twin screw compounder, and a matt film was prepared using an inflation film forming machine (manufacturer, device name). . At this time, die temperature was 230 degreeC and cooling water temperature was 20 degreeC. In order to measure the properties of the manufactured matte film, the results of measuring the matte characteristics (gloss) with a glossiness detector (gloss detector), the impact strength with a Spencer impact strength was shown in Table 1 below.

At this time, the matte property is the value when light is reflected on the test material at a certain angle (45 °) and the reflected light is received at the same angle as the incident light. ).

Comparative Example 1

To prepare a film was carried out in the same manner as in the above-described resin composition composed as shown in Table 1, the analysis results thereof were compared to Table 1 below.

Comparative Example 2

To prepare a film by using the embossing method of giving the concave-convexities to the cooling composition of the resin composition as shown in Table 1, the analysis results were compared and analyzed in Table 1 below.

Yes Composition ratio Glossiness Impact strength (kgm) First component (wt%) Second component (% by weight) Tertiary component (ppm) 4th ingredient (ppm) Fifth component (ppm) 6th ingredient (wt%) 7th ingredient (ppm) Comparative Example 1 Homo 100% - 3,500 1,600 - - 79 10 Comparative Example 2 Homo 100% - 1,500 - - - 23.3 10 Example 1 Homo 85% HDPE 10% 3,500 1,600 5% - 14 10 Example 2 Homo 80% HDPE 15% 3,000 1,500 5% - 11 11 Example 3 Homo 80% HDPE 15% 3,000 1,500 5% 200 ppm 13 11 Example 4 70% random HDPE 20% 5,000 2,500 - - 12 13 Example 5 60% random HDPE 30% 5,000 3,000 EPR 10% - 8 14 Example 6 Homo 85% HDPE 15% - - - - - 16 11 Example 7 85% random HDPE 15% - - 3,000 - - 17 13 Example 8 90% random HDPE 10% - - - - - 18 15

In Table 1, "homo" of the first component refers to homo polypropylene, and "random" refers to random polypropylene containing 2.2% by weight of ethylene in Examples 4, 5 and 7, Example 8 represents a random polypropylene containing 2.5% by weight of ethylene and 5% by weight of butene-1, the third component is synthetic silica having an average particle size of 3.0 μm, and the fourth component is oleamide and It is a mixture of erucamides. In addition, in Table 1, a component added in small amounts in "ppm" within a range that does not significantly affect the composition range of the composition according to the present invention is described as an additional component of more than 100% by weight.

As can be seen in Table 1, it can be seen that the film according to the present invention exhibits excellent matt properties and impact strength, compared to the film of the prior art.

As can be seen through the above examples and comparative examples, the film produced according to the present invention has fine matte irregularities formed on the surface is diffusely reflected light has excellent matt properties, excellent impact strength and general inflation processing equipment High-quality matte film that can be processed can be produced.

Claims (7)

50 to 95 weight percent of a random polypropylene resin comprising homo polypropylene or ethylene and / or butene-1 having a melt index of 20 dg / min or less; And Matte characterized by melting index of 1.0dg / min or less, density of 0.919∼0.970g / cm ³ and copolymerization of alpha-olefin having 3 to 10 carbon atoms with ethylene or 5-50% by weight of ethylene homopolymerized resin Polyolefin resin composition having characteristics. The composition of claim 1, wherein the composition comprises 0.0001 to 1% by weight of silica (SiO ₂ ) having an average particle size of 10 µm or less; An organic slip agent selected from the group consisting of oleamide, erucamide, and mixtures thereof, 0.0001 to 1% by weight and / or 0.0001 to 1% by weight of an antistatic agent. The ethylene-propylene copolymer (EPR), ethylene-propylene-diene terpolymer (EPDM) and molten according to claim 1, wherein the composition comprises 30 to 80% by weight of ethylene having a melt index of 1.0 dg / min or less. 5-30% by weight of one polymer selected from the group consisting of ethylene vinyl acetate comprising 70% or more by weight of ethylene having an index of 1.0 dg / min or less; And 10 to 300 ppm of a peroxide, wherein the polyolefin resin composition has a matte property. 50 to 95 weight percent of a random polypropylene resin comprising homo polypropylene or ethylene and / or butene-1 having a melt index of 20 dg / min or less; And a melt index of 1.0 dg / min or less, a density of 0.919 to 0.970 g / cm ³ , and a matte property including 5 to 50% by weight of a copolymer resin of alpha olefin and ethylene having 3 to 10 carbon atoms or ethylene homopolymerization resin. Matte film, characterized in that the polyolefin resin composition was produced using an inflation film molding method. The method of claim 4, wherein the polyolefin resin composition comprises 0.0001 to 1% by weight of silica (SiO ₂ ) having an average particle size of 10 μm or less; A matte film further comprising 0.0001 to 1% by weight of an organic slip agent and / or 0.0001 to 1% by weight of an antistatic agent selected from the group consisting of oleamide, erucamide, and mixtures thereof. The ethylene-propylene copolymer (EPR) and ethylene-propylene-diene terpolymer (EPDM) according to claim 4, wherein the polyolefin resin composition comprises 30 to 80% by weight of ethylene having a melt index of 1.0 dg / min or less. And 5 to 30 weight percent of one polymer selected from the group consisting of ethylene vinyl acetate comprising 70 weight percent or more of ethylene having a melt index of 1.0 dg / min or less; And 10-300 ppm of peroxide. The matt film according to claim 4, wherein the molding method is carried out under a condition that the temperature of the resin extruded from the die is 180 to 250 ° C and the cooling water temperature is less than 30 ° C.