JPH05156099A - Polypropylene resin composition for producing wax - Google Patents

Abstract

PURPOSE:To provide the subject composition composed of a propylene polymer, an antioxidant and an acid absorbent, having colorless transparent appearance in molten state, free from the corrosion of apparatuses such as reactor in the production of wax by thermal decomposition and giving a wax having excellent color and appearance. CONSTITUTION:The objective composition is produced by compounding (A) a propylene polymer having a melt flow rate of 1-100g/10min (a non-deashed polypropylene produced by the liquid-phase polymerization in the presence of a highly active supported catalyst composed of a solid catalyst component containing titanium and magnesium chloride, an organic aluminum compound and a stereoregularity improver) with (B) an antioxidant consisting of a compound of formula (R1 and R1' are aryl, alkyl, etc.; Y1 is phosphorus or alkyl), (C) an acid absorbent preferably consisting of a higher fatty acid metal salt and/or a hydrotalcite and (D) an organic peroxide.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polypropylene resin composition as a wax raw material. More specifically, a polypropylene resin composition that does not corrode a device such as a reactor during thermal decomposition, is colorless and transparent when melted, and can easily produce a wax having an excellent appearance and hue with high productivity. It is about things. [0002]

2. Description of the Related Art Conventionally, polypropylene wax among polyolefin waxes is chemically stable, has a low melt viscosity, a high softening point, a large hardness, a good compatibility with various plastics, and an excellent electrical property. Since it has features such as rubber and plastic processability improver / pigment dispersant, paraffin wax modifier, abrasion resistance of printing ink / paint, blocking resistance modifier, and toner binder for electronic copying machines. Widely used as a modifier.

Generally, a polypropylene wax is produced by using polypropylene as a raw material, adding or not adding an organic peroxide, heating and melting it, and thermally decomposing it. Today, polypropylene used as the above raw material is a demineralized product obtained by polymerizing using a highly active supported catalyst comprising a solid catalyst component containing titanium and magnesium chloride, an organoaluminum compound and a stereoregularity improver. It started to come. However, when such a non-decalcified product is used as a raw material for a wax, the produced wax is colored by residual chlorine because chlorine atoms remain in the product, and the appearance such as hue is deteriorated. Further, if the residual chlorine exceeds 5 ppm, it causes corrosion of equipment such as a reactor for producing wax, and therefore it is required to solve the problem.

[0004]

The object of the present invention is to provide a wax which is colorless and transparent when melted and which does not corrode a device such as a reactor during the production of wax by thermal decomposition and has an excellent appearance such as hue. The present invention provides a polypropylene resin composition for producing wax, which can be produced with high productivity.

[0005]

Means for Solving the Problems As a result of intensive research and development for solving these problems, the present inventors have found that a polypropylene resin composition containing a propylene polymer and a specific antioxidant and an acid absorber is They have found that they can solve the problems and have completed the present invention.

[0006] The invention of claim 1 of the present invention is the following (a) ~
(C) A polypropylene resin composition for wax production, which is characterized by comprising: (A) Propylene-based polymer having a melt flow rate of 1 to 100 g / 10 min (b) Antioxidant having a structure of the following formula (1) (c) Acid absorbent

[0007]

[Chemical 4]

The invention of claim 2 of the present invention is the polypropylene resin composition for wax production according to claim 1, characterized in that (d) an organic peroxide is further added to the composition.

The invention of claim 3 of the present invention is characterized in that the antioxidant having the structure of formula (1) is one or more compounds represented by the following formula (2) or (3). Item 1
Alternatively, it is the polypropylene resin composition for wax production according to item 2.

[0010]

[Chemical 5]

[0011]

[Chemical 6]

The invention of claim 4 of the present invention is the polypropylene resin composition for producing wax according to claims 1 to 3, wherein the acid absorbent is a higher fatty acid metal salt and / or hydrotalcite.

According to a fifth aspect of the present invention, the propylene polymer used as a raw material is a highly active supported catalyst comprising a solid catalyst component containing titanium and magnesium chloride, an organoaluminum compound and a stereoregularity improving agent. The polypropylene resin composition for wax production according to claim 1, which is a deash-free product polymerized by use. The present invention will be described in detail below.

As the propylene-based polymer used in the present invention, propylene homopolymer having a highly crystalline stereospecific structure, propylene-based random copolymer, propylene-based block copolymer and the like can be used. Examples of the α-olefin copolymerized with propylene include ethylene, butene-1, 4-methylpentene-1, hexene-1, octene-1, decene-1, dodecene-1. Ethylene and butene as the α-olefin
It is preferable to use 1, and ethylene is particularly preferable.

The propylene-based copolymer used in the present invention is
Propylene homopolymer produced by polymerizing in a liquid phase or a gas phase using a highly active supported catalyst comprising a solid catalyst component containing at least titanium and magnesium chloride, an organoaluminum compound, and a stereoregularity improving agent. Or a binary copolymer of propylene and α-olefin, a ternary or more random copolymer, even without deashing,
It may be decalcified, for example, the chlorine content is 5ppm
The non-deashed propylene-based random copolymer as described above can also be used as the raw material of the present invention.

The propylene-based polymer has a melt flow rate (hereinafter abbreviated as MFR) of 1 to 100 g / 10 mi.
n, preferably 5 to 70 g / 10 min, more preferably 6 to 6
Polymers in the range 0 g / 10 min are preferably used. Among these, it is preferable to use a propylene-based random copolymer or a propylene homopolymer from the viewpoint of easiness of thermal decomposition, thermal characteristics of the wax, hardness, and the like, and particularly, to use a propylene / ethylene random copolymer. Is preferred.

As the antioxidant used in the present invention, antioxidants such as phenol-based antioxidants, aromatic amine-based antioxidants, phosphorus-based antioxidants and thioether-based antioxidants can be used, but they are colorless when melted. In order to produce a wax that is transparent and has an excellent appearance such as hue, it is preferable to use at least one selected from the group consisting of antioxidants having the structure of the following formula (1).

[0018]

[Chemical 7]

As an example of the compound represented by the formula (1), R
_The following are examples of residues of ₁ and R ₁ ^′ .

[0020]

[Chemical 8]

Among the antioxidants represented by the formula (1), it is particularly preferable to use one or more of the antioxidants having the structure of the following formula (2) or (3) in the present invention.

[0022]

[Chemical 9]

[0023]

[Chemical 10]

As the antioxidant represented by the formula (2),
Dibenzyl-pentaerythritol-di-phosphite, bis (2,4-di-t-butyl-phenyl) pentaerythritol-di-phosphite, bis (2-t-butyl-)
4-methylphenyl) pentaerythritol-di-phosphite, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-di-phosphite, bis (2-cyclohexylphenyl) pentaerythritol-
Examples include di-phosphite, di (nonylphenyl) pentaerythritol-di-phosphite, distearyl-pentaerythritol-di-phosphite, and ditridecyl-pentaerythritol-di-phosphite, but especially distearyl-pentaerythritol. -Di-phosphite, bis (2,4-di-t-butyl-phenyl)
Pentaerythritol-di-phosphite and bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol-di-phosphite are preferred.

As the antioxidant represented by the formula (3),
3,9-bis [2- {3- (3-t-butyl-4-hydroxy
-5-methylphenyl) propionyloxy} -1,1-dimethylethyl] -2,4,8,10-tetraoxaspiro [5,5] undecane can be mentioned. The structural formula is shown below.

[0026]

[Chemical 11]

As the antioxidant represented by the formula (3),
Further, the following compounds may be mentioned.

[0028]

[Chemical 12]

The amount of the above antioxidant added is 0.005
It is used in the range of 0.1 parts by weight. If it is less than this range, the antioxidant effect is reduced, and if it is more than this range, it becomes difficult to thermally decompose,
It becomes impossible to produce a wax excellent in appearance and hue with high productivity.

As the acid absorbent of the present invention, conventionally used higher fatty acid metal salts, blends of higher fatty acid metal salts and higher fatty acids, hydroxy higher fatty acid metal salts, hydrotalcites, epoxy compounds. Etc. can be used, but in order to produce a wax having a sufficient effect as an acid absorber, a wax produced by thermally decomposing the composition is colorless and transparent when melted, and has an excellent appearance and hue. The acid absorbent added to the polypropylene resin composition of the present invention is preferably a higher fatty acid metal salt and / or hydrotalcite.

As the higher fatty acid metal salt, lauric acid,
Myristic acid, palmitic acid, stearic acid, oleic acid, linoleic acid, linolenic acid, behenic acid and other higher fatty acids and lithium, sodium, magnesium, metal salts of alkali metals or alkaline earth metals such as calcium, and the like, In particular, it is more preferable to use calcium stearate and / or sodium stearate as the higher fatty acid metal salt.

Hydrotalcites are double salt compounds represented by the following formula. (M ²⁺ ) _1-X Al _X (OH) ₂ (A ⁿ⁻ ) _{X / n} · mH ₂ O (where 0 <x ≦ 0.5, m: real number, M ²⁺ : Mg, Ca
Alternatively, Zn, A ^n- : n-valent anion. As these compounds, both natural products and synthetic products are used, but synthetic products in which M ²⁺ is Mg and A ⁿ⁻ is CO ₃ ²⁻ are particularly preferable.

The amount of the acid absorbent added is 0.005 to 0.
1 part by weight is preferred. If the amount added is less than 0.005 parts by weight, the effect as an acid absorbent will be reduced and the piping of the equipment such as the reactor may be corroded. If the amount added exceeds 0.1 parts by weight, the produced wax is colorless when melted. It will not be transparent, and it will not be possible to produce a wax having an excellent appearance and hue.

In the present invention, it is preferable to add an organic peroxide in order to more efficiently thermally decompose the polypropylene composition during thermal decomposition. The organic peroxide used in the present invention is used in advance in the polypropylene resin composition to adjust the MFR to 1 to 100 g / 10 min. Although the MFR can be adjusted only by the polymerization conditions, the MFR can be adjusted more easily by the thermal degradation method in the presence of the organic peroxide.

The organic peroxide is 2,5-
Hydroperoxides such as dimethylhexane-2,5-dihydroperoxide, t-butylperoxide and diisopropylbenzene peroxide, α
α'-bis (t-butylperoxyisopropyl) benzene, dialkyl peroxide such as 2,5-dimethyl-2,5-di (t-butylperoxy) hexane, t
-Peroxyesters such as -butylperoxyacetate, t-butylperoxybenzoate, 2,5-dimethyl-2,5- (benzoylperoxy) hexane, and organic peroxides such as ketone peroxide such as methylethylketone peroxide However, the present invention is not limited to these.

The amount of the above-mentioned organic peroxide added is generally 0.001 to 1 part by weight, but it is not particularly limited and may be appropriately selected depending on the starting propylene polymer, the properties of the wax, the wax production conditions and the like. Can be decided.

To produce the polypropylene resin composition of the present invention, a propylene polymer, an antioxidant represented by the formula (1), an acid absorbent such as a higher fatty acid metal salt and / or hydrotalcite, Further, if necessary, organic peroxide and other additives are blended, and these are dry blended with an ordinary tumbler, a Henschel mixer, or the like, and are usually mixed with a Banbury mixer, a pressure kneader, a single screw extruder, a twin screw extruder, or the like. It can be made by melt-kneading with a kneader.

The method for producing a wax using the polypropylene resin composition of the present invention may be such that the composition is melted and pyrolyzed in an oxygen atmosphere or an inert gas atmosphere under the condition that the composition is pyrolyzed. Although not limited thereto, a known Banbury mixer, a pressure kneader, an autoclave, a single-screw extruder, a twin-screw extruder, a tubular reactor or the like is used in a batch system or continuously, the melting temperature, the pressure, and the residence time. It is preferable to set the conditions under which optimum thermal decomposition occurs by controlling the above.

[0039]

EXAMPLES The present invention will be described in detail below with reference to examples, but the invention is not limited to these examples without departing from the gist of the invention. (Examples 1 to 12, Comparative Examples 1 to 17) MFR: 18 g / 10
min, ethylene content 2.8% by weight, residual chlorine content 1
Using 100 parts by weight of 0 ppm demineralized propylene-ethylene random copolymer, the antioxidant, acid absorbent and organic peroxide [bis (t-butylperoxyisopropyl) benzene, perbutyl P, Japan shown in Table 1 were used. Oil and fat] 0.017 parts by weight are dry-blended, then melt-kneaded using a single-screw extruder and thermally degraded at a resin temperature of 220 ° C. to obtain a polypropylene resin composition for wax raw material having MFR: 44 g / 10 min. And Melt appearance test of polypropylene resin composition, corrosiveness test of polypropylene resin composition with respect to equipment such as reactor, 5% weight loss temperature was measured by a thermobalance as a guide for thermal decomposability, and the results are shown in Table 1. Indicated.

The test method is shown below. (A) Melt appearance test of polypropylene resin composition: The polypropylene resin composition was placed in a test tube under N ₂ atmosphere 38
After standing at 0 ° C. for 30 minutes, the hue and transparency of the melt-pyrolyzed resin composition are visually observed. (B) Corrosion test of polypropylene resin composition for reactors and the like: The polypropylene resin composition is put into a test tube and melted at 230 ° C. under N ₂ atmosphere, and then the soft iron plate is immersed in the molten resin for 2 hours. .. After that, the soft iron plate was taken out to remove the adhered composition, and a constant temperature and humidity chamber (80 ° C, 90%
RH) and left for 20 hours, and the extent of rust generation was determined by the rust generation area. 10% or less is ◯, 50% or more is x,
The middle of the two was set as Δ. (C) Measuring method of 5% weight loss temperature by thermobalance: TG / DTA200 type manufactured by Seiko Denshi Kogyo Co., Ltd. was used and the temperature was raised from 70 ° C to 500 ° C at a heating rate of 10 ° C / min under N ₂ atmosphere. Then, measure the temperature when the weight of the sample is reduced by 5%. The abbreviations in Table 1 represent the following.

A: Distearyl-pentaerythritol-
Di-phosphite B: bis (2,4-di-t-butylphenyl) pentaerythritol-di-phosphite C: bis (2,6-di-t-butyl-4-methylphenyl)
Pentaerythritol-di-phosphite D: 3,9-bis [2- {3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionyloxy} -1,
1-Dimethylethyl] -2,4,8,10-tetraoxaspiro [5.5] undecane E: Tetrakis [methylene-3- (3,5-di-t-butyl-
4-hydroxyphenyl) propionate] methane F: tris (2,4-di-t-butylphenyl) phosphite G: tris (mixed-mono-and-di-nonylphenyl) phosphite H: calcium stearate I: stearin Sodium acid salt J: Synthetic hydrotalcite, Mg _0.7 Al _0.3 (OH)
₂ (CO ₃ ) _0.15・ 0.5H ₂ O K: Lithium stearate L: Octyl epoxy stearate

[0042]

[Table 1]

As shown in Table 1, the antioxidants have the abbreviations A, B, C and D, and the acid absorbents have the abbreviations H,
Only in the case of Examples using I and J, good thermal decomposability, good appearance and hue when the produced wax is melted, and the polypropylene resin composition is not corrosive to devices such as reactors. In contrast, the abbreviation E, which is a conventional phenol-based antioxidant, or the abbreviations F and G, which are phosphite-based antioxidants having no pentaerythritol group, and higher fatty acid metal salts are used. In the case of the comparative example using a certain abbreviation symbol K or an abbreviation symbol L which is an epoxy acid absorbent, the appearance and hue of the produced wax when melted are poor, and the polypropylene resin composition corrodes equipment such as a reactor. You can see that there are cases.

(Examples 13 to 16) MFR: 8g / 10mi
n, 2.7% by weight of ethylene and 12 ppm of residual chlorine were used in Example 1, using a demineralized propylene-ethylene random copolymer.
The antioxidant, acid absorbent, and 0.038 parts by weight of organic peroxide used in Nos. 5, 9, and 10 were dry-blended, and further melt-kneaded using a single-screw extruder to obtain a resin temperature of 2
It was thermally degraded at 20 ° C. to obtain a polypropylene resin composition for wax raw material having MFR: 42 g / 10 min. The results are shown in Table 2. However, the abbreviations in Table 2 are the same as those in Table 1.

(Examples 17 to 20) Polypropylene resin for wax raw material having MFR: 41g / 10min, except that 0.01 parts by weight of the abbreviations H and J are added as an acid absorbent. It was a composition. The results are shown in Table 2.
It was shown to. However, the abbreviations in Table 2 are the same as those in Table 1.

(Examples 21 to 24) MFR: 8g / 10mi
n, 14 ppm residual chlorine was used in the same manner as in Examples 13 to 16 except that a demineralized propylene homopolymer was used. MFR: 46
A polypropylene resin composition for a wax raw material having a g / 10 min was obtained. The results are shown in Table 2. However, the abbreviations in Table 2 are the same as those in Table 1.

(Examples 25 to 28) As an organic peroxide, 0.05-weight of 2,5-dimethyl-2,5-di (t-butylperoxy) hexane [Perhexa 25B, manufactured by NOF CORPORATION]. Example 21-
The same procedure as in Example 24 was performed to obtain a polypropylene resin composition having a MFR of 48 g / min as a wax raw material. The results are shown in Table 2. However, the abbreviations in Table 2 are the same as those in Table 1.

(Examples 29 to 32) MFR: 50 g / mi
n, using chlorine-free demineralized propylene homopolymer having a residual chlorine of 10 ppm, except that no organic peroxide was used.
The same procedure as in Example 28 was conducted to obtain a polypropylene resin composition for wax raw material. The results are shown in Table 2. However, the abbreviations in Table 2 are the same as those in Table 1.

[0049]

[Table 2]

[0050]

As described above, the present invention provides an antioxidant and a higher fatty acid metal salt and / or an acid absorbent such as hydrotalcites which are specific to the non-decalcified propylene-based copolymer or homopolymer, Further, by adding an organic peroxide as required, a wax produced when melted is colorless and transparent, and the melt does not corrode a device such as a reactor and is excellent in appearance and hue due to thermal decomposition. It has the effect of providing a polypropylene resin composition that can be easily produced with high productivity.

Claims (5)

[Claims] 1. A polypropylene resin composition for wax production, comprising the following (a) to (c): (A) Propylene-based polymer having a melt flow rate of 1 to 100 g / 10 min (b) Antioxidant having a structure of the following formula (1) (c) Acid absorbent embedded image 2. The polypropylene resin composition for wax production according to claim 1, further comprising (d) an organic peroxide added to the composition. 3. The wax production according to claim 1, wherein the antioxidant having the structure of formula (1) is one or more compounds represented by the following formula (2) or (3). Polypropylene resin composition for use. [Chemical 2] [Chemical 3] 4. The polypropylene resin composition for wax production according to claim 1, wherein the acid absorbent is a higher fatty acid metal salt and / or hydrotalcite. 5. A propylene-based polymer used as a raw material was polymerized using a highly active supported catalyst comprising a solid catalyst component containing titanium and magnesium chloride, an organoaluminum compound and a stereoregularity improver. The polypropylene resin composition for manufacturing wax according to claim 1, which is an ash product.