JPS58222130A - Polyethylene composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. which has excellent pigment- or additive- dispersibility and does not suffer the formation of flow marks, etc., by using a linear ethylene (co)polymer having an MW higher than that of wax and lower than that of normal ethylene (co)polymer. CONSTITUTION:A PE compsn. consists of 40-90pts.wt. linear ethylene/alpha-olefin copolymer or linear ethylene polymer (A) having a melt index of 50-200g/min and molecular weight distribution (MW/MN) (a ratio of weight-average MW to number-average MW) of 4 or below, and 60-10pts.wt. pigment and/or additive such as antioxidant (B). A masterbatch contg. the polymer A is characterized in that it has excellent B component dispersibility and does not suffer the formation of flow marks, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention contains additives such as pigments and antioxidants at high concentrations, and furthermore, mixes them with (1) olefin resin;
The present invention relates to a polyethylene composition that has excellent dispersibility of pigments and additives when diluted, and this polyethylene composition is used as a master patch for formula olefin resins.

In the present invention, the polyolefin fruit tree JJl is an ethylene polymer, polypropylene, polybutene, poly4-methylpentene-1, ethylene-α-olefin copolymer, or the like.

Generally, various methods have been proposed for coloring the above-mentioned polyolefin resin, but two types of colorants are usually used industrially: dry color and masterbatch. Dry color is a powder coloring agent made by treating dyes or pigments with metal soap, etc. In this dry coloring method, the final product is made by directly molding the mixture that is uniformly mixed with resin and dry color in a mixing machine such as a tumbler. Color pellets can be obtained by mixing in an extruder.

(2) There are some difficulties with the dry coloring method regarding the dispersibility of the pigment in the final colored product, and the colorant scatters when measuring and mixing the colorant, so resin molding manufacturers are concerned about the working environment. In order to obtain a B11 olefin resin colored product with uniform pigment dispersion, a high concentration of pigment is pre-dispersed in a resin that has good compatibility with the B11 olefin resin or polyolefin resin. Stearing masterbatches are mainly used. However, the surface of polyolefin resins is extremely non-polar, making them inert and causing poor dispersion of pigments during coloring. Acid metal salts 1.11 Wax etc. have been added, but in order to obtain the desired degree of dispersion, large amounts of the above additives are required, which often causes uneven coloring called flow marks and surface bleeding of wax. It became.

Father, General [Pigment concentration 3 to obtain master patch
Must be kept below 0%. For example, if a master batch containing a concentration of 30% or more of Ff is used, the final required concentration is diluted with a polyolefin resin (natural resin) that does not contain pigments. However, it is difficult to obtain a colored product having a uniform pigment dispersion due to poor elasticity and decomposition properties.

On the other hand, various methods are known in which transfer additives such as antioxidants are mixed with polyolefin resin, but the method using an additive master patch requires a mixing process with natural resin that does not contain additives. This is a preferred method in the workplace because it is simple and does not require the use of powder additives. In this case as well, a master patch containing as high a concentration of additives as possible is desired, but polyolefin resins and various additives that are generally polar have poor compatibility, and at high concentrations, the additives bleed to the surface of the resin. Because the particles are slippery, it is impossible to produce mask patch pellets, and it is necessary to set an upper limit on the number of degrees that can be produced for each additive.

In order to overcome the problems of these additive master patches such as pigments and/or antioxidants, the present inventors have developed
Through research, we have discovered that a master made of ethylene polymer or ethylene/α-olefin copolymer has a molecular weight higher than that of wax, but lower than normal ethylene polymer or ethylene/α-olefin copolymer. The present invention was achieved based on the discovery that the batch has excellent dispersibility of additives such as pigments and antioxidants, and does not generate flow marks.

That is, the present invention has a melt index (MI) of 50 to 20 Of/10m1n1. Molecular weight distribution (MW/
This is a polyolefin composition comprising 40 to 90 parts by weight of a linear ethylene polymer or linear ethylene/α-olefin copolymer having a MN) of 4 or less, and 10 to 60 parts by weight of a pigment and/or an additive.

The present invention will be explained in detail below.

The linear ethylene polymer or linear ethylene/α-olefin copolymer used in the present invention is a transition metal oxide catalyst such as a chromium oxide catalyst using alumina as a carrier,
Transition metal halides of groups ■~■, such as titanium halides or vanadium halides, and organic aluminum magnesium complexes, such as alkyl aluminum-magnesium complexes, alkyl alkogysia aluminum-magnesium complexes, etc. Using a catalyst other than a radical catalyst, such as a coordination polymerization catalyst such as a Ziegeler catalyst, which is a combination of an organometallic compound of the group T, such as an organoaluminum compound such as aluminum chloride, algyl aluminum or alkylaluminum chloride, Turbid polymerization, solution polymerization,
Gas phase polymerization, and 500-6000 atm, 150°-6
Ethylene homopolymers or ethylene and propylene, phthene-1, pentene-1, hexene-1,4-methylpentene-1, octene-1, decene, etc. can be produced by various processes such as pressure polymerization in which polymerization is carried out at 50°C. It is a copolymer with one or more α-olefins such as -1.

The polymer used in the present invention is 50 to 200 f/10 m
It has a high melt index in the 1n range. In a preferred embodiment, the polymer is 80-150f/10m1n
It has a melt index in the range of .

For melt index below 50 f/10m1n,
Poor fluidity and poor dispersibility of pigments and additives. On the other hand, 20
When the melt index is 0 f/'lomin or higher, the molecular weight is too low, causing problems such as the generation of flow marks similar to those of wax and the formation of deposits on the surface of resin molded products. Further, if the melt index is 200 or more, melt cutting is difficult, making it difficult to produce pellets, and master pellets cannot be produced industrially and efficiently.

The polymer used in the present invention has a weight average molecular weight (MW)
It is necessary that the molecular weight distribution (M#/MN') expressed as the ratio of the number average molecular weight (MN) and the number average molecular weight (MN) be 4 or less, preferably 6.5 or less. The ratio of MY to MN is determined by del permeation chromatography. If the value of M W /M H exceeds 4, extremely low molecular weight polymers will be included, causing problems such as generation of flow marks similar to wax and bleeding onto the surface of resin molded products.

The vinyl group content of the polymer used in the present invention is preferably 0.7 or more per 1000 carbons. The content of vinyl groups is measured by engineering R spectrum. If the vinyl group content is less than 0.7/1000 carbons, the dispersibility of additives such as pigments and antioxidants is poor. Ethylene polymers and ethylene/α-olefin copolymers are extremely nonpolar, but they have 4 to 8 times more vinyl bonds in one polymer than normal ethylene polymers and ethylene/α-olefin copolymers. It is presumed that this is because the pole is higher than that of the previous model.

The density of the polymer used in the present invention is 0.900 to 0.9
It is desirable to be in the range of 70g h3. It is desirable that a masterbatch produced by boiling a high-density polymer is used for olefin-based resins having a high melting point such as t%m&polyethylene and polypropyne. Furthermore, masterbatches manufactured using low-density polymers can be used for volatile polyolefin resins, and are particularly suitable for various types of low-density polyethylene.

The polymers used in the present invention are described in W, E!, published November 17, 1970. , Baker, ■, O,B.

It can be prepared by polymerizing ethylene or a mixture of ethylene and alpha-olefins using the process disclosed in Canadian Patent No. 856,137 by John F. Sanders and J.M. Stewart. In such a process, ethylene monomer mixed with an alpha-olefin is dissolved in an inert solvent, such as cyclohexane, and introduced into the reaction door. The monomers are polymerized or copolymerized in the presence of a catalyst, which is separately diluted in a solvent and injected into the reaction chamber. Pressure and temperature are controlled so that the resulting polymer dissolves in the solvent. Hydrogen can be supplied to the reactor to obtain and control the desired melt index and/or molecular weight distribution.

The polymerization catalyst is normally deactivated as soon as the ethylene polymer or ethylene/α-olefin copolymer leaves the reaction zone. After catalyst deactivation, the polymer can be removed by removing catalyst residue if necessary, flashing the solvent from the polymer, extruding the polymer into water, and cutting the pellets into other suitable comminuted shapes. I can do it. Pigments used in the present invention include, for example, copper phthalocyanine pigments, anthraquinone pigments, quinacridone pigments, perylene pigments, isoin-quinoline pigments, monoazo pigments, disazo-based pigments, condensed acetate-based pigments, and titanium oxide pigments. , iron oxide, chromium oxide, cadmium pigments, carbon black, etc.

Additives include various antioxidants, such as sulfur compounds such as dilauryl-3,3'-thiodipropionic acid ester, phenolic compounds such as decylhyroxytoluene, bisphenol compounds, 2-hyroxy-4-methoxy These include ultraviolet absorbers such as benzophenone, surfactants such as glycerin fatty acid esters and alkyl sulfonates, petroleum waxes, higher fatty acids, higher fatty acid metal salts, fatty acid esters of alcohols, and higher fatty acid amides.

The composition of the present invention contains 40 to 90 parts by weight of a linear ethylene polymer or a linear ethylene/α-olefin copolymer mixed with 10 to 60 parts by weight of a pigment and/or an additive. If the concentration of these pigments and additives in the blend is less than 10 parts, it is not preferable in terms of efficiency of the masterbatch, and if the concentration is more than 60 parts, the dispersibility is poor.

It goes without saying that it is advantageous for the effectiveness of the masterbatch to increase the concentration as much as possible without compromising the dispersibility, but this maximum allowable concentration depends on the pigments, additives, and their secondary properties. By combining multiple species,
Each can be determined, but the melt index is 50 f.
The maximum permissible concentration is higher than that when using conventional polyethylene or polyethylene copolymers of less than /10 m1n.

The composition of the present invention can be prepared by mixing a linear ethylene polymer or a linear ethylene-α-olefin copolymer with a pigment and/or an additive using a conventional kneading machine, such as a mixer, a Banbury,
It is produced by a method of kneading the polymer at a temperature equal to or higher than its melting point using one or more kneader-1 extruders.

The invention will be further illustrated by the following examples. In the example, the load was 10 because of the high flow rate of the polymer.
AsTMD-1 except using a weight of 60t
It was measured according to the 238 method (conditions)!l). The melt index was then determined from the extrapolated calibration curve obtained using a polymer with a melt index less than 100.

Vinyl impregnation in the polymer shows trans bonds, terminal vinyl bonds, and vinyl-11 dene bonds in infrared absorption spectra of 964 crn-'', 908 cm-', and 8 cm-', respectively.
88cIn-'' absorption was used to determine the amount, and the results were totaled.

[Production of polymer]

Ethylene alone or a mixture of ethylene and butene □-11 in cyclohexane solution was polymerized in a 1001 stirred autoclave reactor in the presence of a catalyst consisting of vanadium oxychloride, titanium tetrachloride, and imprenyl aluminum. Hydrogen was fed to the reactor. The reaction was terminated using an organic acid quencher and the polymer was then separated from the cyclohexane to produce Polymers AD. The details of the experiment and the results obtained are shown in Table 1.

Table 1 Experiment number 1 26 4 Fee ethylene (creation 15 15 16
18butene-1 (%) OO016
Hydrogen (ppm) 72' 43 100
3 Temperature ('0) Inlet 40 41 45 39
Exit 282 275 281 265
Ethylene conversion rate (%) 97 96 9
8 97 Polymer density (r/c, 2) 0.960 0.9600.9
61 0.923 Melt Index 100
30 170 120()7101
0m1 n)/MN 3.1 4・2
3.1 3.3 Example 1 40 parts of copper phthalocyanine blue, 60 parts of polymer A, and antioxidant (Ciba Geigy Ilga Knox 1010)
Add 2 parts and place this mixture in a steam heated nigu;
Pressure kneading is carried out for about 15 minutes while adjusting the vapor pressure of the kneader to 5 to 6 kg 10 n''.Then, the kneader is cooled, unkneaded materials inside are removed, and the kneader is heated again.
After kneading for about 30 minutes at a vapor pressure of 5 to 6 kg/cm2, the kneader was cooled, the mixture was coarsely crushed, dried, and passed through a 50-liter extruder! The mixture was melt-cut to obtain masterbatch pellets with a pigment content of 40% by weight.

2 parts of master birch thus obtained and high density 71
? Mix Il ethylene (density 0.957, melt index 0.6 > 98 parts, 50% L/D==2
When a colored film of 20 μm was formed using a Modern Machine 11 g inflation film forming machine, a uniformly colored film without colorant spots or color unevenness was obtained. A mixture of the above masterbatch and high-density poly(1) ethylene was spun using a small spinning machine of 33 parts m/m.
When a monofilament was produced by drawing it to a denier, the coloring composition was dispersed and a knotted yarn was generated due to poor diffusion.
A colored yarn with excellent appearance and no yarn breakage phenomenon was obtained.

Comparative Example 1 40 parts of copper phthalocyanine blue and 860 parts of polymer,
Antioxidant (Ciba Gaia, Irganox 1010)
A pigment master patch was prepared in the same manner as in Example 1 by adding 2 parts. When a film was formed using this in the same manner as in Example 1, a large number of particles of 50 microns or more were present in the colored film, and a good colored film could not be obtained. Similarly, polyethylene monofilament was produced according to the method of Example 1, but the production of knobby yarns was observed, and yarn breakage occurred during drawing.

Example 2 40 parts of copper phthalocyanine green, 060 parts of polymer,
Antioxidants (Chipa J Year, Ilga Knox 1010)
2 parts of the formulation was mixed according to the method of Example 1,
A mask-patch containing 40 parts by weight of pigment was obtained. When this was mixed with Q-dense W polyethylene to produce a colored film (20μ) according to the method of Example 1, a uniformly colored film with no spots or unevenness was obtained.

Comparative Example 2 A colored film (20μ) was produced according to the method of Example 2, except that Polymer B was used instead of Polymer C. Spots and color unevenness were observed in this colored film.

Comparative Example Filtration A colored film (20
When .mu.) was produced, wax stains and color unevenness were observed in this colored film.

Example 6 40 parts of copper phthalocyanide, 0 parts of polymer D6,
Antioxidant Wholesale 1 (Chipagayer Irganox 1010
), put this mixture into a steam heating kneader, adjust the steam pressure of the kneader to 4-5 kg 10n'', and mix under pressure for about 15 minutes.Then, cool down the kneader. , remove the internal unkneaded material, strain it, and heat the ni gu again.
After kneading for about 30 minutes at a vapor pressure of 4 to 5 kg/lyn, the kneader was cooled, the mixture was coarsely crushed, dried, and
The mixture was melt-cut using a Shizu extruder to obtain master patch pellets with a pigment content of 40% by weight.

Two parts of the master patch obtained in this way and a low density,
Mixed with 98 parts of Je I+Eethin (density 0.920, melt index 0.7), 50 class L/D=
When a colored film of 20 μm was formed using a blown film forming machine manufactured by Modern Machinery No. 28, a uniformly colored film with no spots or color unevenness was obtained.

Example 4 Two parts of the master patch with a pigment content of 40% by weight produced in Example 1 were mixed with 98 parts of high-density polyethylene (density 0.958, melt index 103), and this was subjected to high-speed injection molding on a commercial scale. Using a machine, a 500 ml, wall thick container for food packaging was molded. The resulting colored container had no flow marks and was uniformly colored.

Example 5 After mixing 80 parts of Polymer A and 20 parts of antioxidant (Chipa Geyer, Ilga Knox 1010) in a Henschel mixer, 200 to 200 parts were mixed in an extruder at L/D = 28 on 65th morning.
After melt-kneading at 3000° C., the extruded strand was continuously cut 17 in water to obtain antioxidant master pellets. The obtained master pellet is coated with an antioxidant on its surface. - The composition was uniform, with no particles observed. 1 part of this master pellet and 99 parts of high-density Bo-11 ethylene pellets (density 1fO, 953, melt index 10) were mixed in a Henschel mixer and then extruded in an extruder, resulting in a uniform and non-bleeding product containing 2000 ppm of oxidizing agent. A pellet was obtained.

Comparative Example 6 An attempt was made to produce an antioxidant masterbatch pellet in the same manner as in Example 5, except that commercially available high-density modified polyethylene (density 0.960, melt index 31) was used instead of Polymer A. However, the fed compound slipped inside the extruder and the resin could not be extruded.

Patent applicant: Asahi Kasei Industries, Ltd. 19-

Claims (1)

[Claims] 1. Melt index is 50 to 200S'/1
0mln, 40 to 90 parts by weight of a linear ethylene polymer or linear ethylene/α-olefin copolymer having a molecular weight distribution (MW/MN) expressed by the ratio of weight average molecular weight to number average molecular weight of 4 or less, and a pigment. and/or additive 1
Polyethylene composition 2, linear ethylene polymer or linear ethylene copolymer consisting of 0 to 60 parts by weight,
Density 0.900-0.970? /c! n3 and a melt index of 80 to 150 r/1[]min, the additives include lubricants, antioxidants, ultraviolet absorbers, Composition 4, linear ethylene polymer or linear ethylene copolymer according to Claims 1 and 2, which is an antistatic agent or an antiblocking agent,
The polyethylene composition according to claims 1 to 3, characterized in that the vinyl content is 0.7/10'00 carbons or more.