JP4020333B2 - Resin composition for extrusion molding - Google Patents

Description

【００４６】
【表２】

【００４７】
【表３】

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実施例９〜１３、１６〜１７、参考例１〜２、比較例１４〜１６および１８〜２０
実施例１と同様にして、表２に示される物性の成分Ａおよび成分Ｂからなるペレット状の樹脂組成物を得た。
得られたペレットを用いて、組成物のＭＦＲ、密度、ＭＴおよびＭＥを測定した。更に該ペレットを厚さ２ｍｍのプレスシートに成形し、ビカット軟化点温度、脆化温度およびＨＡＺＥを測定した。これらの結果を表２に示す。
【００５１】
参考例３
成分Ａに表２に示す物性のものを用い、成分Ｂに低密度ポリエチレン（三菱油化製“三菱ポリエチ”ＬＬ ＳＦ５２０）を用いた以外は、実施例１と同様にして樹脂組成物を調製し、評価した。その結果を表２に示す。
【００５２】
比較例１７
成分Ａに三井石油化学工業製 ウルトゼックス １５２０Ｌを用いた以外は、実施例１と同様にして樹脂組成物を調製し、評価した。その結果を表２に示す。
【００５３】
比較例２１
成分Ａを用いずに、成分Ｂのみを用いて実施例９と同様に評価し、その結果を表２に示す。
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【表６】

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【表７】

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【表８】

【００５７】
【表９】

【００５８】
上記実施例１と比較例５の評価結果を対比すると、本発明の組成物は、ヒートシール性、耐寒性、食品衛生性（ヘプタン可溶分が少ない）に優れていることがわかる。また、実施例４と比較例５とは、同一密度の組成物であるが、前者が耐熱性、食品衛生性に優れていることがわかる。
【００５９】
【発明の効果】
このような本発明の押出成形体用樹脂組成物は、従来のＬＬＤＰＥよりも加工性が改良され、かつ透明性、耐熱性、耐寒性等が良好であり、またアンチブロッキング性のバランスに優れ、衝撃強度、ヒートシール性、耐熱性、耐寒性等のフィルム性能が従来品より格段に良好であるといった効果が奏されるために、スナック、インスタントラーメン等の乾燥食品、味噌、漬物、スープ、ジュース等の水物食品、冷凍食品、畜肉、ハム等の食品等の包装、醤油、ソース等のミニパックや、輸液、注射剤、粉末、錠剤等の各種医薬品の包装および充填用材料、例えば、バッグインボックス、輸液バッグ等、シャンプー、化粧品等のミニパック、カセットテープ、電気機器等の各種包装・充填用フィルム、各種蓋材として極めて有用なものである。[0001]
[Industrial application fields]
The present invention provides a resin composition which has improved processability and is excellent in transparency, heat resistance, cold resistance, impact strength, heat sealability, food hygiene, etc., particularly for molding a film or sheet. It is about.
[0002]
[Prior art]
Conventionally, polypropylene resins have been known as materials for extrusion molded articles such as films and sheets having good transparency. Films molded from this polypropylene resin are widely used as various packaging materials because of their excellent rigidity and the like. However, on the other hand, polypropylene film is not suitable for general-purpose processing methods such as air-cooled inflation molding and has disadvantages such as poor impact strength, cold resistance, and low-temperature heat sealability. It was limited.
Therefore, in the field of general-purpose films, high-pressure low-density polyethylene (hereinafter simply referred to as “LDPE”), which is a resin that can compensate for these drawbacks, has been widely used. However, this LDPE is effective in compensating for the above-mentioned drawbacks, but has the disadvantage that the transparency is inferior to that of the polypropylene.
[0003]
On the other hand, using a Ziegler catalyst, for example, a copolymer of ethylene and α-olefin produced by a method described in Japanese Patent Publication No. 56-18132, etc., so-called linear low density polyethylene (hereinafter simply referred to as “LLDPE”). (Abbreviated) is a resin superior in impact strength, heat sealability, hot tackiness, heat resistance, cold resistance, etc. than the above-mentioned LDPE resin. Further, the transparency of the LLDPE can be improved by performing special processing such as a known T-die molding method, a water-cooled inflation molding method, and an air-cooled inflation molding method using a special air ring. Are known.
However, when the film surface of LLDPE is made smooth to make a film with good transparency, the low crystalline component in LLDPE bleeds out to the surface, so the anti-blocking property is greatly reduced. Practical use becomes difficult.
Therefore, in order to improve such problems, a method of adding an antiblocking agent such as silica or talc or a slip agent to this LLDPE has been adopted. Transparency reduces the transparency, and it is difficult to improve the original transparency of the resin.
In recent years, by using a new catalyst described in JP-A-58-19309, etc., LLDPE having a narrower composition distribution than before can be obtained, and transparency and blocking properties are higher than those of conventional LLDPE. Although there is a possibility of improvement, the molecular weight distribution becomes narrow, so that the workability is greatly deteriorated.
In addition, conventional LLDPE has better heat resistance and cold resistance than polypropylene and low density polyethylene, but is subjected to high-temperature sterilization treatment and is stored under refrigeration at -50 ° C or lower, particularly recently at -80 ° C or lower. Satisfy the application to medical products and containers for cryogenic storage that require performance such as transparency so that the container is not damaged and the condition inside the container is visible during storage. I couldn't.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide an extruded product, particularly a film or sheet, which has good processability and has greatly improved performance such as transparency, heat resistance and cold resistance, and can be used to produce a film or sheet. It is in.
[0005]
[Means for Solving the Problems]
[Summary of the Invention]
As a result of intensive studies on means for improving workability and obtaining a well-balanced material while maintaining these excellent performances, the present inventors have a specific property with LDPE having a specific property. The inventors have obtained knowledge that the object of the present invention can be achieved by blending with LLDPE, and have completed the present invention.
[0006]
  That is, the resin composition of the present invention is
  Component A: having the following properties (a) to (d)Obtained using metallocene-based catalystsCopolymer of ethylene and α-olefin having 4 to 12 carbon atoms
                                                          50-99% by weight
(A) MFR is 0.1 to 5 g / 10 min
(B) Density (D) is 0.88 to 0.925 g / cm³
(C)o-Dichlorobenzene was used as a solventOne peak of the elution curve obtained by temperature rising elution fractionation (TREF),
The peak temperature is 35-85 ° C.,
The value of H / W is 1 or more when the height of the peak is H and the width of half of the height of the peak is W.
(D)o-Dichlorobenzene was used as a solventElution amount at 50 ° C. (Y:% by weight relative to the total amount of component A) by temperature rising elution fractionation (TREF) satisfies the following conditions.
(1) The density (D) of component A is 0.91 g / cm³When less than
Y ≦ −4500D + 4105 (Y ≦ 100)
(2) The density (D) of component A is 0.91 g / cm³When it is above
Y ≦ 10
  Component B: high pressure having the following properties (a ′), (b ′), (c ′) and (d ′)Radical polymerization1-50% by weight of ethylene polymer selected from low density polyethylene
(A ') MFR is 0.1 to 20 g / 10 min
(B ′) Density of 0.915 to 0.93 g / cm³
(C ') Memory effect (ME) is 1.3 or more
(D ') Melt Tension (MT) is 2.5 g or more
It is characterized by comprising.
[0007]
                          [Detailed Description of the Invention]
[1] Component
(1) Component A (Obtained using a metallocene catalystEthylene / α-olefin copolymer having 4 to 12 carbon atoms)
(A) Property
  Component A constituting the resin composition of the present inventionObtained using a metallocene catalystAs the α-olefin copolymer having 4 to 40 ethylene atoms, it is important to use the following (1) to (4) physical properties, and (5) physical properties to be used. Is preferred.
[0008]
▲ 1 ▼ MFR
Ethylene and carbon number used in the present invention4-12The α-olefin copolymer of MFR (Melt Flow Rate: Melt Flow Rate) according to JIS-K7210 is 0.1 to 5 g / 10 minutes, preferably 0.3 to 4 g / 10 minutes, particularly preferably. Those having physical properties of 0.7 to 3.5 g / 10 min are used.
When the MFR is larger than the above range, heat resistance and cold resistance are lowered, and film formation becomes unstable. On the other hand, if the MFR is smaller than the above range, the resin pressure becomes too high, and the moldability is deteriorated or the production amount of the product is lowered, which is not practical.
[0009]
▲ 2 ▼ Density
Ethylene and carbon number used in the present invention4-12The α-olefin copolymer of JIS-K7112 has a density of 0.88 to 0.925 g / cm3, preferably 0.89 to 0.92 g / cm3, particularly preferably 0.90 to 0.915 g / cm3. It is shown.
When the density is larger than the above range, transparency and heat sealability become poor. On the other hand, if the density is too small, the heat resistance deteriorates or the film surface becomes sticky and cannot be practically used.
[0010]
  (3) Peak temperature of elution curve obtained by temperature rising elution fractionation
  Used in the present inventionObtained using a metallocene catalystThe ethylene / C4-C12 α-olefin copolymer is:o-Dichlorobenzene was used as a solventThere is one peak of the elution curve obtained by temperature rising elution fractionation (TREF), and the peak temperature is 30 to 100 ° C, preferably 35 to 85 ° C, particularly preferably 40 to 70 ° C, and The value of H / W is 1 or more, preferably 1-20, particularly preferably 1-15, where H is the height of this peak and W is ½ the height of the peak. Preferably the physical property of 1-10 is shown.
  When the peak temperature of the elution curve exceeds the rising temperature, the transparency is lowered and the low-temperature heat sealability is poor, which is impractical. In addition, when the peak temperature of the elution curve is lower than the above temperature, the product bleeds out and the film is sticky, which is not practical.
  When the above H / W is less than the above value, the product bleeds out, the sticky component increases, and the heat sealability becomes poor with time, which is impractical.
[0011]
(4) The elution amount at 50 ° C. (Y:% by weight relative to the total amount of component A) by temperature rising elution fractionation (TREF) satisfies the following conditions.
1) The density (D) of component A is 0.91 g / cm^ThreeWhen less than
Y ≦ −4500D + 4105 (where Y ≦ 100), preferably
Y ≦ −4650D + 4238 (where Y ≦ 100).
2) The density (D) of component A is 0.91 g / cm^ThreeWhen it is above
Y ≦ 10, preferably Y ≦ 7.
Elution curve measurement by temperature rising elution fractionation
Measurement by temperature rise elution fractionation (TREF) is based on the principles described in "Journal of Applied Polymer Science, Vol 26, 4217-4231 (1981)" and "Polymer debate proceedings 2P1C09 (1985)". This is done as follows.
First, a polymer to be measured is completely dissolved in a solvent. Thereafter, it is cooled to form a thin polymer layer on the surface of the inert carrier. Such a polymer layer is formed such that those that are easily crystallized are formed on the inner side (side closer to the surface of the inert carrier) and those that are difficult to crystallize are formed on the outer side.
Next, when the temperature is raised continuously or stepwise, the low temperature stage elutes from the amorphous part in the polymer composition of interest, that is, the polymer having a high degree of short-chain branching, and gradually increases as the temperature rises. Those having a small degree of branching are eluted, and finally a linear part having no branching is eluted and the measurement is completed.
The concentration of the eluted component at each temperature can be detected, and the composition distribution of the polymer can be seen by a graph drawn by the amount and temperature of elution.
[0012]
▲ 5 ▼ Q value
This ethylene carbon number4-12The α-olefin copolymer has a Q value (weight average molecular weight / number average molecular weight) determined by size exclusion chromatography (SEC) of 4 or less, preferably 3 or less, particularly preferably 2.5 or less. Those exhibiting the above physical properties are preferred.
When the Q value exceeds the above range, the appearance of the molded product tends to deteriorate.
[0013]
(B) Ethylene / carbon number4-12Of α-olefin copolymer
Ethylene and carbon number used in the present invention4-12No. 58-19309, 59-95292, 60-35005, 60-35006, 60-35007, 60-35008, JP-A-60-35009, JP-A-6130-30314, JP-A-3-1638308, European Patent Application Publication No. 420436, US Pat. No. 5,055,438 and International Publication No. WO91 / 04257, etc. A metallocene catalyst, in particular a metallocene / alumoxane catalyst, or a metallocene compound as disclosed in, for example, International Publication No. WO92 / 01723 and the metallocene compound described below. Using a catalyst composed of a compound that becomes an anion, the main component ethylene and the secondary component α -A method of copolymerizing with olefins.
[0014]
The compound that reacts with the above metallocene compound to become a stable anion is an ionic compound or electrophilic compound formed from an ion pair of a cation and an anion, and reacts with the metallocene compound to become a stable ion. It forms a polymerization active species.
[0015]
Among these, an ionic compound is represented by the following general formula (I).
Formula (I) [Q]^{m +}[Y]^m-      (M is an integer of 1 or more)
Q is a cation component of an ionic compound, and includes a carbonium cation, a tropylium cation, an ammonium cation, an oxonium cation, a sulfonium cation, a phosphonium cation, and the like. Examples include organic metal cations.
These cations are not limited to cations that can give protons as disclosed in JP-A-1-501950 and the like, but also cations that do not give protons. Specific examples of these cations include triphenylcarbonium, diphenylcarbonium, cycloheptatrienium, indenium, triethylammonium, tripropylammonium, tributylammonium, N, N-dimethylanilinium, dipropylammonium, dicyclohexylammonium, Triphenylphosphonium, trimethylphosphonium, tri (dimethylphenyl) phosphonium, tri (methylphenyl) phosphonium, triphenylsulfonium, triphenyloxonium, triethyloxonium, pyrylium, silver ion, gold ion, platinum ion, palladium ion, Examples include mercury ion and ferrocenium ion.
[0016]
Y is an anion component of an ionic compound, which is a component that reacts with a metallocene compound to become a stable anion, and is an organic boron compound anion, an organic aluminum compound anion, an organic gallium compound anion, an organic phosphorus compound anion, an organic Examples include arsenic compound anions, organic antimony compound anions, and more specifically, tetraphenylboron, tetrakis (3,4,5-trifluorophenyl) boron, tetrakis (3,5-di (trifluoromethyl) phenyl) boron , Tetrakis (3,5- (t-butyl) phenyl) boron, tetrakis (pentafluorophenyl) boron, tetraphenylaluminum, tetrakis (3,4,5-trifluorophenyl) aluminum, tetrakis (3,5-di ( Trifluoromethyl) pheny ) Aluminum, tetrakis (3,5-di (t-butyl) phenyl) aluminum, tetrakis (pentafluorophenyl) aluminum, tetraphenylgallium, tetrakis (3,4,5-trifluorophenyl) gallium, tetrakis (3,5 -Di (trifluoromethyl) phenyl) gallium, tetrakis (3,5-di (t-butyl) phenyl) gallium, tetrakis (pentafluorophenyl) gallium, tetraphenylphosphorus, tetrakis (pentafluorophenyl) phosphorus, tetraphenylarsenic Tetrakis (pentafluorophenyl) arsenic, tetraphenylantimony, tetrakis (pentafluorophenyl) antimony, decaborate, undecaborate, carbadodecaborate, decachlorodecaborate and the like.
[0017]
Among electrophilic compounds, among those known as Lewis acid compounds, they react with metallocene compounds to form stable anions to form polymerization active species, and as various metal halide compounds and solid acids, Examples include known metal oxides. Specific examples include magnesium halides and Lewis acidic inorganic oxides.
[0018]
α-olefin
Here, as the α-olefin, carbon number4-12Α-olefins such as 1-butene, 1-pentene, 1-hexene, 1-octene, 1-heptene, 4-methylpentene-1, 4-methylhexene-1, 4,4-dimethylpentene-1, etc. Is mentioned. Among these α-olefins,4 to 12 carbon atoms, preferably 6 to 10 carbon atomsIt is preferable to copolymerize 2 to 60% by weight, preferably 5 to 50% by weight, and 40 to 98% by weight, preferably 50 to 95% by weight, of one or more α-olefins.
[0019]
Copolymerization
Examples of the polymerization method include a gas phase method, a slurry method, a solution method, and a high-pressure ion polymerization method. Among these, the solution method and the high-pressure ion polymerization method are preferable, and the production by the high-pressure ion polymerization method is particularly preferable.
The high-pressure ion polymerization method is described in JP-A-56-18607 and JP-A-58-225106, and the pressure is 200 kg / cm.²Or more, preferably 300 to 2,000 kg / cm², A continuous process for producing an ethylene-based polymer, which is carried out under reaction conditions of a temperature of 125 ° C. or higher, preferably 130 to 250 ° C., particularly 150 to 200 ° C.
[0020]
(2) Component B (ethylene polymer)
(A) Properties
It is important to use the ethylene-based polymer of component B constituting the extruded molded body resin composition of the present invention having the following physical properties (1) to (3), and (4) to (6). It is preferable to use a material exhibiting the physical properties of.
[0021]
▲ 1 ▼ MFR
The ethylene-based polymer used in the extruded molded body resin composition of the present invention has an MFR (Melt Flow Rate) of 0.1 to 20 g / 10 minutes according to JIS-K7210, preferably 0.8. It exhibits physical properties of 5 to 10 g / 10 minutes, particularly preferably 1.0 to 5.0 g / 10 minutes.
If the MFR is larger than the above range, the moldability deteriorates and the film formation becomes unstable. Moreover, when MFR is too smaller than the said range, the extrudability and the external appearance of a molded product will become defect.
[0022]
▲ 2 ▼ Density
The ethylene polymer used in the present invention has a density according to JIS-K7112 of 0.88 to 0.93 g / cm.^Three, Preferably 0.915-0.93 g / cm^ThreeMore preferably, 0.918-0.927 g / cm^ThreeParticularly preferably, 0.919 to 0.923 g / cm^ThreeIt shows the physical properties.
When the density is higher than the above range, the transparency is deteriorated and the low-temperature heat sealability is poor. On the other hand, if the density is too smaller than the above range, the product bleeds out and the film surface becomes sticky.
[0023]
(3) Memory effect (ME: Memory Effect)
The ethylene polymer used in the present invention has a ME (3 g) of 1.3 or more, preferably 1.6 or more, particularly preferably 2.0 or more, and most preferably 2.3 or more. preferable.
If the ME is too small, the moldability becomes unstable, which is not preferable.
The ME (3 g) was measured as follows, using the melt indexer used in JIS-K7210, setting the measurement conditions to a cylinder temperature of 240 ° C., and a constant speed extrusion rate of 3 g / min. Is done.
Fill the apparatus with sample, place only piston, and after 6 minutes apply the specified extrusion speed. Next, a graduated cylinder containing ethyl alcohol is placed directly under the orifice, and a straight extrudate is collected.
The diameter (D) of the sampled extrudate is measured with a micrometer, and the orifice diameter of the die is D₀As follows, ME is obtained by the following equation.
ME = D / D₀
[0024]
(4) Q value
This ethylene polymer is obtained by size exclusion chromatography (SEC) and has a Q value (weight average molecular weight / number average molecular weight) of 5 to 30, particularly preferably 7 to 25, most preferably 10 to 20. Those showing physical properties are preferred.
If the Q value is larger than the above range, the appearance of the molded product tends to deteriorate, such being undesirable. On the other hand, if the Q value is too small, the moldability tends to become unstable.
(5) The melt tension (MT: Melt Tension: melt tension at break) is 1.0 g, preferably 1.5 g or more, more preferably 2.5 g or more, and particularly preferably 5 g or more.
If MT is too smaller than the above value, molding becomes unstable.
(6) ME / MT has the following relationship:
ME ≧ 0.05 × MT + 1.3, preferably ME ≧ 0.05 × MT + 1.5
Satisfying the relationship shown above is significant in terms of the workability improvement effect during molding.
[0025]
(B) Specific examples of ethylene polymers
As an ethylene polymer,Ethylene polymers selected from high-pressure low-density polyethylene can be used. In particular, the reaction temperature during polymerization is 220 ° C. or higher, and the reaction pressure is 1,700 kg / cm.²In the following, it is preferable to use high-pressure radical polymerization low-density polyethylene produced by the autoclave method.
[0026]
[II] Physical properties and quantity ratio of the composition
(1) Physical properties
Preferred resin compositions of the present invention generally have an MFR according to JIS-K7210 of 0.5 to 10 g / 10 minutes, preferably 1 to 8 g / 10 minutes, particularly preferably 2 to 5 g / 10 minutes; 0.88-0.925 g / cm^Three, Preferably 0.89 to 0.92 g / cm^Three, Particularly preferably 0.90 to 0.915 g / cm^ThreeME is 1.0 to 2.0, preferably 1.1 to 1.8, particularly preferably 1.2 to 1.6; MT (50 m / min stress) is 0.3 to 10 g. , Preferably 0.5 to 5 g, particularly preferably 1 to 5 g.
Moreover, ME and MT (50 m / min stress) of the composition are
ME ≧ [0.08 × MT + 1] / g, preferably
The relationship of ME ≧ [0.2 × MT + 1.1] / g is satisfied.
[0027]
(2) Quantity ratio
Ethylene / carbon number of component A4-12An α-olefin copolymer of Component BHigh pressure method low density polyethylene, selected from ethylene / α-olefin copolymers other than component AThe blend ratio with the ethylene polymer is such that component A is 50 to 99% by weight and component B is 1 to 25% by weight, preferably component A is 75 to 99% by weight and component B is 1 to 25% by weight, and more preferably. The component A is 80 to 97% by weight, the component B is 3 to 20% by weight, particularly preferably the component A is 85 to 95% by weight and the component B is 5 to 15% by weight.
When the blending ratio of the component A is too smaller than the above range, heat sealability, transparency and the like are poor. On the other hand, when the blending ratio of the component B is less than the above range, the workability improving effect is insufficient.
[0028]
[III] Production of resin composition
(1) Merge
The resin composition for an extrusion-molded article of the present invention is obtained by the same method as the method for producing a normal resin composition, and the ethylene / carbon number of component A is as follows.4-12Of α-olefin copolymer and component BHigh-pressure low density polyethylene, ethylene polymer selected from ethylene / α-olefin copolymers other than component AIt can manufacture by mix | blending.
Specifically, component A and component B are usually melted and kneaded using an extruder, a Brabender plastograph, a Banbury mixer, a kneader blender, and the like, and are usually formed into pellets by a commonly used method. . A film can be produced using the pellets.
[0029]
(2) Other additives
The resin composition for an extruded molded body of the present invention includes auxiliary additives generally used for resin compositions such as antioxidants (in particular, phenol-based and phosphorus-based antioxidants are preferable), antiblocking agents. , Slip agents, heat stabilizers, light stabilizers, ultraviolet absorbers, neutralizers, antifogging agents, colorants, and the like can be blended.
About antioxidant, an antiblocking agent, and a slip agent, it is a preferable aspect to mix | blend the specific amount of what is described below.
[0030]
[IV] Manufacture of extruded products
A film or sheet can be produced by molding using the pellets.
As a film production method, a film suitable for a packaging material can be obtained by air-cooled inflation molding, air-cooled two-stage cooling inflation molding, T-die film molding, water-cooled inflation molding, or the like.
Sheets suitable for packaging materials can be obtained by calendering, extrusion molding, compression molding, casting, and the like.
[0031]
【Example】
Experimental examples consisting of examples and comparative examples will be described below to explain the present invention more specifically.
[I] Physical property measurement method and evaluation method
Measurement and evaluation of physical properties in Examples and Comparative Examples were carried out by the following methods.
(1) Measurement of physical properties
(A) MFR: Conforms to JIS-K7210 (190 ° C, 2.16 kg load)
(B) Density: Conforms to JIS-K7112.
(C) ME: A melt indexer used in JIS-K7210 was used, and measurement conditions were set at a cylinder temperature of 240 ° C. and a constant speed extrusion rate of 3 g / min.
Fill the apparatus with sample, place only piston, and after 6 minutes apply the specified extrusion speed. Next, a female cylinder containing ethyl alcohol is placed directly under the orifice, and a straight extrudate is collected. The diameter (D) of the sampled extrudate is measured with a micrometer, and the orifice diameter of the die is D₀Then, ME is obtained by the following equation.
ME = D / D₀
[0032]
(D) Measurement of elution curve: The peak of the elution curve by temperature rising elution fractionation (TREF) in the present invention is once dissolved at a high temperature and then cooled to form a thin polymer layer on the surface of the inert carrier. Then, the temperature is raised continuously or stepwise to recover the eluted component, its concentration is continuously detected, and the peak of the graph (elution curve) drawn by the elution amount and elution temperature The polymer composition distribution is measured.
[0033]
The elution curve was measured as follows.
A cross fractionation device (CFC T150A manufactured by Mitsubishi Yuka Co., Ltd.) was used as the measurement device, and the measurement was performed according to the measurement method in the attached operation manual.
This cross-fractionation device is a temperature-exclusion elution fractionation (TREF) mechanism that separates samples using the difference in dissolution temperature, and a size exclusion chromatograph (SEC) that further sorts the classified sections by molecular size. Is a device that is connected online.
[0034]
First, a sample (copolymer) to be measured is dissolved at 140 ° C. using a solvent (o-dichlorobenzene) so as to have a concentration of 4 mg / ml, and this is injected into a sample loop in the measuring apparatus. . The following measurements are automatically performed according to the set conditions.
The sample solution retained in the sample loop is separated into TREF columns (a stainless steel column attached to the apparatus with an inner diameter of 4 mm and a length of 150 mm filled with glass beads as an inert carrier) that is separated using the difference in dissolution temperature. 0.4 ml is injected. The sample is then cooled at a rate of 1 ° C./min from 140 ° C. to 0 ° C. and coated on the inert carrier. At this time, a polymer layer is formed on the surface of the inert carrier in the order of a high crystalline component (which is easily crystallized) to a low crystalline component (which is difficult to crystallize). After the TREF column is held at 0 ° C. for another 30 minutes, 2 ml of components dissolved at the temperature of 0 ° C. are transferred from the TREF column to the SEC column (3 AD80M / S manufactured by Showa Denko KK) at a flow rate of 1 ml / min. Injected.
While fractionation by molecular size is performed by SEC, the temperature is raised to the next elution temperature (5 ° C.) in the TREF column, and held at that temperature for about 30 minutes. Measurement of each elution segment by SEC was performed at 39 minute intervals. The elution temperature is raised stepwise at the following temperature.
0, 5, 10, 15, 20, 25, 30, 35, 40, 45, 49, 52, 55, 58, 61, 64, 67, 70, 73, 76, 79, 82, 85, 88, 91, 94, 97, 100, 102, 120, 140 ° C
[0035]
The solution fractionated by the molecular size on the SEC column was measured for absorbance proportional to the polymer concentration with an infrared spectrophotometer attached to the device (wavelength 3.42μ, detected by stretching vibration of methylene). A chromatogram is obtained.
Using the built-in data processing software, the base line of the chromatogram of each elution temperature segment obtained by the above measurement is drawn and processed. The area of each chromatogram is integrated and an integrated elution curve is calculated. Also, the differential elution curve is calculated by differentiating the integral elution curve with temperature. The calculation result is output to the printer. The differential elution curve that was output is plotted with the elution temperature 89.3 mm per 100 ° C. on the horizontal axis and the differential amount on the vertical axis (the total integrated elution amount is 1.0 and the change at 1 ° C. is the differential amount. ) 76.5 mm per 0.1. Next, the value obtained by dividing the peak height (mm) of this differential elution curve by the width (mm) of ½ height was defined as H / W.
[0036]
(E) Q value: Size Exclusion
Using Chromatography (SEC), measurement was performed under the following measurement conditions, and the Q value was determined from the weight average molecular weight / number average molecular weight. A universal calibration curve was prepared with monodisperse polystyrene and calculated as the molecular weight of linear polyethylene.
Model: Waters Model 150C GPC
Solvent: o-dichlorobenzene
Flow rate: 1 ml / min
Temperature: 140 ° C
Measurement concentration: 2 mg / ml
Injection volume: 200 μl
Column: Showa Denko Co., Ltd. AD80M / S 3 pieces
(F) MT: Using Toyo Seiki Capillograph 1-B, with a test temperature of 190 ° C. and an extrusion speed of 1 cm / min, the take-up speed when taking out the extruded molten resin, and the composition of LDPE at break About the thing, the stress at 50 m / min was measured.
[0037]
(2) Evaluation method
(A) Haze: Conforms to JIS-K7105
(B) Hexane soluble matter:
(1) Cylindrical filter paper is dried under reduced pressure at a temperature of 60 ° C., accurately weighed every 2 hours, and repeated until the difference from the previous time becomes 5 mg or less. Next, about 5 g of the sample is precisely weighed and placed in a cylindrical filter paper.
{Circle around (2)} Reflux extraction is performed with 200 cc of hexane in a high-temperature Soxhlet extruder for 3 hours. The reflux ratio is 3 to 4 times / 10 minutes.
(3) After cooling to room temperature, the extraction residue is dried under reduced pressure for 2 hours at 60 ° C. together with the cylindrical filter paper.
(4) Allow to cool for 30 minutes in a desiccator, then weigh accurately.
(5) Obtained by the following formula.
Hexane soluble content (% by weight) = (W1 + W3-W2) / W1
W1: Sample weight before extraction (g)
W2: Weight of sample after extraction and cylindrical filter paper (g)
W3: Weight of unused cylindrical filter paper (after drying under reduced pressure) (g)
[0038]
(C) Heptane-soluble content: Conforms to standard tests for equipment and containers / packaging of standard standards for food additives, etc. (Ministry of Health and Welfare Notification No. 370 in 1959)
Elution conditions: 25 ° C., 60 minutes
(D) DDI (Dirt Drop Impact): Conforms to JIS-Z1707
(E) 300 g heat-sealing temperature: Sealing pressure: 2 kg / cm at intervals of 75 ° C. to 5 ° C. with a Toyo Seiki hot plate heat sealer², Sealing time: Heat seal in 1 second, and measure the heat seal strength with a tensile tester. The temperature at which 300 g of this heat seal strength is obtained is defined as the 300 g heat seal temperature.
(F) Vicat softening point temperature: Conforms to JIS-K7206
(G) Brittle temperature: Conforms to the Dentsu laboratory method (notch depth: 0.3 mm)
(H) Stability of bubbles: the maximum value of the folding diameter in 50 m for the film formed
L_AAnd the minimum value is L_BWhen
C (%) = [(L_A-L_B) / {1/2 (L_A+ L_B)}] × 100
When C (%) is 20% or less, it is considered good.
[0039]
[II] Experimental example
Example 1
Production of ethylene / C4-C12 α-olefin copolymer (component A)
The catalyst was prepared by the method described in JP-A No. 61-130314. That is, to the 2.0 mol of complex ethylene-bis (4,5,6,7-tetrahydroindenyl) zirconium dichloride, 1,000 mol times of methylalumoxane manufactured by Toyo Stofa Co., Ltd. was added to the above complex, and 10 liters of toluene was added. The catalyst solution was prepared by diluting the solution and polymerized by the following method.
A mixture of ethylene and 1-hexene was supplied to a stirred autoclave type continuous reactor having an internal volume of 1.5 liter so that the composition of 1-hexene was 80% by weight, and the pressure in the reactor was 1,000 kg. The reaction was carried out at a temperature of 150 ° C.
After completion of the reaction, the MFR is 3.3 g / 10 min, the density is 0.905 g / cm 3, the Q value is 2.0, and the peak of the TREF elution curve is one, and the peak temperature is 62 ° C. An ethylene / α-olefin copolymer having a H / W of 4 and an elution amount at 50 ° C. of 12% by weight (1-hexene content: 15% by weight) was obtained.
[0040]
Manufacture of high-pressure low-density polyethylene (component B)
Reaction temperature 260 ° C, reaction pressure 1,500 kg / cm²In the autoclave method. MFR 4g / 10min, density 0.92g / cm^ThreeA high-pressure low-density polyethylene having a ME of 2.4, a Q value of 10, and an MT of 9.4 g was obtained.
[0041]
Production of resin composition
An ethylene / α-olefin copolymer (component A) and a high-pressure low-density polyethylene (component B) as shown in Table 1 were blended at a ratio of component A: component B = 95: 5 wt%, A pellet-shaped resin composition comprising an ethylene / α-olefin copolymer (component A) and high-pressure low-density polyethylene (component B) is granulated at a molding temperature of 160 ° C. with a 40 mmφ single-screw extruder. Obtained.
[0042]
Evaluation
This pellet-shaped resin composition was press-molded, and the Vicat softening point and the embrittlement temperature were measured.
Furthermore, this pellet-shaped resin composition was film-formed under the following conditions with a 40 mmφ inflation molding machine manufactured by Tommy Machine Industry.
Screw: Diameter 40mmφ
L / D: 24
Die: Diameter 75mmφ
Die lip: 3mm
Molding temperature: 180 ° C
Film thickness: 30 μm
Frost line: 180mm
Screw speed: 60rpm
Blow ratio: 2.0
Chiller: 15 ° C
The obtained film was evaluated. The evaluation results are shown in Table 1.
[0043]
Examples 2-8, Comparative Examples 1-4 and 6-13
A resin composition was obtained by preparing in the same manner as in Example 1 except that those having the physical properties described in Table 1 were used as Component A and Component B. This was molded and evaluated.
The obtained evaluation results are as shown in Table 1.
[0044]
Comparative Example 5
A resin composition was obtained in the same manner as in Example 1 except that an ethylene / α-olefin copolymer produced with a Ziegler catalyst was used as Component A. This was molded and evaluated. The obtained evaluation results are as shown in Table 1.
[0045]
[Table 1]

[0046]
[Table 2]

[0047]
[Table 3]

[0048]
[Table 4]

[0049]
[Table 5]

[0050]
Example9-13, 16-17, Reference Examples 1-2,Comparative Examples 14-16 and 18-20
  In the same manner as in Example 1, a pellet-shaped resin composition composed of component A and component B having physical properties shown in Table 2 was obtained.
  Using the obtained pellets, the MFR, density, MT and ME of the composition were measured. Further, the pellet was formed into a press sheet having a thickness of 2 mm, and Vicat softening point temperature, embrittlement temperature, and HAZE were measured. These results are shown in Table 2.
[0051]
Reference example 3
  A resin composition was prepared in the same manner as in Example 1 except that components A having physical properties shown in Table 2 were used, and low density polyethylene (Mitsubishi Yuka "Mitsubishi Polyethylene" LL SF520) was used as component B. ,evaluated. The results are shown in Table 2.
[0052]
Comparative Example 17
A resin composition was prepared and evaluated in the same manner as in Example 1 except that Mitsui Petrochemical Industries' Ultrazex 1520L was used as Component A. The results are shown in Table 2.
[0053]
Comparative Example 21
Evaluation was made in the same manner as in Example 9 using only Component B without using Component A, and the results are shown in Table 2.
[0054]
[Table 6]

[0055]
[Table 7]

[0056]
[Table 8]

[0057]
[Table 9]

[0058]
Comparing the evaluation results of Example 1 and Comparative Example 5 above, it can be seen that the composition of the present invention is excellent in heat sealability, cold resistance, and food hygiene (having little heptane-soluble content). Moreover, although Example 4 and Comparative Example 5 are compositions having the same density, it can be seen that the former is excellent in heat resistance and food hygiene.
[0059]
【The invention's effect】
Such a resin composition for an extruded product of the present invention has improved processability than conventional LLDPE, and has good transparency, heat resistance, cold resistance, etc., and excellent anti-blocking balance, Because it has the effect that film performance such as impact strength, heat sealability, heat resistance, and cold resistance is much better than conventional products, dried foods such as snacks and instant noodles, miso, pickles, soup, juice Packaging for foods such as marine foods, frozen foods, livestock meat, ham, etc., minipacks such as soy sauce, sauces, etc., and packaging and filling materials for various pharmaceuticals such as infusions, injections, powders, tablets It is extremely useful as an inbox, infusion bag, etc., shampoo, cosmetics and other minipacks, cassette tapes, various packaging and filling films for electrical equipment, and various lids.

Claims (1)

Component A: a copolymer of ethylene and an α-olefin having 4 to 12 carbon atoms obtained by using a metallocene catalyst having the following properties (a) to (d)
50-99% by weight
(A) MFR is 0.1 to 5 g / 10 minutes (b) Density (D) is 0.88 to 0.925 g / cm ³
(C) One peak of the elution curve obtained by temperature-elevated elution fractionation (TREF) using o-dichlorobenzene as a solvent ,
The peak temperature is 35-85 ° C.,
H / W value is 1 or more, where H is the height of the peak and W is ½ the height of the peak. (D) Temperature rise using o-dichlorobenzene as a solvent Elution amount at 50 ° C. by elution fractionation (TREF) (Y:% by weight with respect to the total amount of component A) satisfies the following conditions. (1) The density (D) of component A is less than 0.91 g / cm ^3. When
Y ≦ −4500D + 4105 (Y ≦ 100)
(2) When the density (D) of component A is 0.91 g / cm ³ or more,
Y ≦ 10
Component B: an ethylene-based polymer selected from high-pressure radical polymerization low-density polyethylene having the following properties (a ′), (b ′), (c ′) and (d ′): 1 to 50% by weight
(A ′) MFR is 0.1 to 20 g / 10 min (b ′) Density is 0.915 to 0.93 g / cm ³
(C ′) Memory effect (ME) is 1.3 or more. (D ′) Melt tension (MT) is 2.5 g or more.