JPS6250352A - Non-rigid olefin resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. having excellent coatability, flow characteristics and resistance to impact, marring, oils and heat, by heating, melting and kneading a resin mixture in the presence of a metal oxide, etc., and uniformly blending it with a polyolefin. CONSTITUTION:A resin mixture of 100pts. (by weight; the same applies hereinbelow) of the combined quantity of 10-90pts. PP (A) having an MFR of 0.3-60g/10min and 90-10pts. halogenated butyl rubber (B) having a Moony viscosity of 25-100 (100 deg.C), 10-120pts. olefin rubber (C) having a Moony viscosity of 25-100 (100 deg.C), an iodine value of 30 or below and an ethylene content of 35-85wt%, 5-120pts. mineral oil softener (D), 1-90pts. modified polyolefin (E) obtd. by adding an unsaturated carboxylic acid (derivative) to a polyolefin and 2-100pts. nitrile rubber (F) is heated, molten and kneaded in the presence of 0.2-10wt% (based on the quantity of the mixture) metal oxide (e.g., ZnO) and/or metal chloride (e.g., ZnCl2) at 160-250 deg.C for 1-10min and uniformly blended with a polyolefin.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a polyolefin-based soft resin composition.

BACKGROUND OF THE INVENTION Conventionally, polyurethane and polypropylene materials have been mainly used for large molded products such as plastic bumpers for automobiles.

However, it has been pointed out that the former is expensive, has poor weather resistance, and has a poor yield during production. On the other hand, the latter contains a large amount of rubber components in order to improve low-temperature impact resistance and flexibility, which causes problems such as easily scratching the surface of the molded product and causing sink marks that are typical of polypropylene. Ta. Olefinic thermoplastic elastomers are attracting attention as a solution to these two problems.

Examples of olefinic thermoplastic elastomers include compositions consisting of polyolefin and partially crosslinked rubber (
Japanese Patent Publication No. 54-25702], and in order to improve the fluidity of this composition, a partially crosslinked polyolefin is added to a composition obtained by treating a polyolefin and a rubber component in the presence of an organic peroxide. Composition (Special Publication 1984)
Japanese Patent Publication No. 15745-15745 and a method for producing a composition (Japanese Patent Publication No. 15740/1983) have been proposed.

Problems to be Solved by the Invention However, the organic peroxide used as a crosslinking agent used in the production of the above partially crosslinked thermoplastic elastomer composition is highly reactive, and therefore the degree of crosslinking must be adjusted to an appropriate level. Because crosslinking and molecular chain scission proceed at the same time, the physical properties of the composition may deteriorate, the low molecular weight products produced may have an adverse effect on paintability, and partial gelation may cause molded products to deteriorate. However, there remained the problem that it was accompanied by rough skin.

Furthermore, there was also the problem that free radicals caused by organic peroxides remained in the molded product, impairing thermal stability.

The present inventors conducted studies to solve the above problems, and as a result, they decided to mix halogenated butyl rubber into the rubber component and react it as a metal oxide and/or metal chloride total crosslinking agent. Thus, a composition consisting of a polyolefin having a network structure by selectively crosslinking halogenated butyl rubber without molecular chain scission and a partially crosslinked rubber component was obtained.

However, although this composition has excellent performance as a thermoplastic elastomer, there is still room for improvement in terms of fluidity in molding large molded products and paintability of molded products. However, there is still room for improvement, especially in applications that require oil resistance and heat resistance.

The present invention has mechanical properties suitable for large molded products without impairing rubber elasticity, particularly impact resistance and surface scratch resistance,
An object of the present invention is to provide an olefin-based soft resin composition that has good paintability and flowability, can obtain molded products that do not generate flow marks or sink marks during molding, and has improved oil resistance and heat resistance.

Means for Solving the Problems As a result of intensive research, the inventors of the present invention compounded halogenated butyl rubber, further modified polyolefin and nitrile rubber as a rubber component, and cross-linked metal oxides and/or metal chlorides. It has been found that the object of the present invention can be achieved by further blending a polyolefin into a composition consisting of a polyolefin reacted as an agent and a partially crosslinked rubber fraction, and the present invention has been completed.

That is, the present invention provides (A) polypropylene 10 to 90
Parts by weight, CB)/90 to 1 oz parts of kudzu rogenated Budel rubber ((A) 100 parts by weight), (C) 10 to 120 parts by weight of olefin rubber, (D) Mineral oil softener 5 ~120 parts by weight, ■) Mixture k consisting of 1 to 90 parts by weight of modified polyolefin and (2 to 100 parts by weight of linitrile rubber), (G) Melted and kneaded by heating in the presence of metal oxide and/or metal chloride. However, the entire gist of the olefin-based soft resin composition is obtained by uniformly blending (b) polyolefin into the material to be kneaded [provided that part or all of (g) modified polyolefin and (F) nitrile rubber are blended uniformly into the kneaded material. (including the case where it is mixed into the material to be kneaded)].

Composition material (A) polypropylene homopolymer of propylene or ethylene, 1-butene,
It is a copolymer whose main component is propylene copolymerized with α-olefins such as 1-pentene, 1-hexene, and 4-methyl-1-pentene. Here, the copolymer includes random and block type copolymers. In addition, the melt flow rate (hereinafter referred to as MFR) is α3~60 f/
10 minutes, preferably 1 to 40 f/710 minutes, and more preferably 5 to 50 f/10 minutes (J0Ag component, hereinafter referred to as the bottom component, has the highest melting point among polyolefins and improves heat resistance and mechanical strength. Contribute to

CB) Halogenated butyl rubber means halogenated inbutylene-isogrene copolymer rubber (hereinafter referred to as component B).

Examples of halogen include chlorine or bromine atoms. The halogen content is usually [15 to 4.0 wt'Ik%].

In addition, component B is M T-+t+s, 100°C, 25-10
It is desirable to have a Mooney viscosity of 0 and a degree of unsaturation of C10 to 4.0 mol.

Component B is a rubber that can be crosslinked with a metal compound or a metal chloride. 11 It is dispersed as a cross-linked rubber in the composition to form a network structure, imparting scratch resistance, heat resistance, rubber elasticity, vibration absorption, gas impermeability, slip resistance, etc.

(0) Olefin rubber Monoolefin copolymer rubber of two or more monoolefins such as ethylene, propylene, 1-phen, '-hexene, 4-methyl-1-pentene (typically is an ethylene-propylene copolymer rubber], as well as two of the above monoolefins (preferably ethylene and propylene) and non-containing compounds such as dicyclopentadiene, 1°4-hexadiene, cyclooctadiene, methylene norbornene, and ethylidene norbornene. Contains a conjugated diolefin or a copolymer rubber with a conjugated diolefin such as butadiene or isoprene (hereinafter referred to as component C).

The C component preferably has a M L1+1.127°C, a Mooney viscosity of 5 to 300, an iodination of up to 50, and an ethylene content of 55 to 85 weight Mt-. In addition, polyisobutylene, butyl rubber, etc. are also included (hereinafter referred to as 0g portion).

Component C exists in the composition as a non-crosslinked rubber, provides flexibility and molding fluidity, and acts as a binder at the phase interface between component A and component B, thereby improving tensile strength and elongation.

(To) Mineral oil-based softener A high-boiling petroleum distillate used to reduce the hardness of vulcanized rubber and increase its flexibility and elasticity.
Examples include naphthenic and aromatic compounds (hereinafter referred to as component C).

Note that among the C components, aromatic components have a negative effect on paintability, and therefore are not preferably used in materials to be coated.

Ω) Modified polyolefin Examples include polyolefins that are added by reacting unsaturated carboxylic acids or derivatives thereof (hereinafter referred to as 17m).

Examples of polyolefins include homopolymers of α-olefins such as ethylene or propylene, 1-butene, 1-pentene, 1-hexene, and 4-methyl-pentene, copolymers of ethylene and α-olefins, or copolymers of these α-olefins. Copolymers of two or more types can be mentioned. Among the above polyolefins, low density polyethylene,
Linear low density polyethylene, medium/high my polyethylene, borizlopylene, propylene-ethylene random or block copolymer, etc. are preferable.

In addition, as unsaturated carboxylic acids, V rain powder, endo-
Bicyclo-[2,2,1]-5-Heguchi7-2.5-
Examples include dicarboxylic acid, itacone, hexamaric acid, acrylic acid, methacrylic acid, and derivatives thereof include acid anhydrides, acid amides, esters, and the like.

All of the various known methods can be used to react the polyolefin with the unsaturated carboxylic acid or its derivative. For example, it can be obtained by adding a reaction initiator such as an organic peroxide to a polyolefin and an unsaturated carboxylic acid or a derivative thereof, mixing them in advance, and then melt-kneading them. Here, the amount of the unsaturated carboxylic acid or its derivative to be added to the polyolefin is preferably from 102 to 2 fl-h.

In addition, the above C component includes an olefin copolymer rubber such as the above C component (Mooney viscosity MLsrs 127 ° C.
5~300, iodine cumulative value up to '5D, ethylene content 35~
Even if it contains olefin rubber such as polyisobutylene (density 191 to α951/ac, molecular!! k (by Staudinger method) of about 60,000 to 135,000) good. When reacting an unsaturated carboxylic acid or its derivative with a mixture of polyolefin and olefin rubber, the mixing ratio is 10-90% by weight of polyolefin, 90-10% by weight of olefin rubber, and the acid addition IL' is α02~21
It is desirable to keep it at i%.

Component E not only improves fluidity, but also enhances the compatibility of each component in the composition as a binder, and improves mechanical strength, especially impact resistance.

CF) Nitrile rubber means acrylonitrile-butadiene copolymer rubber (hereinafter referred to as 11F component). Acrylonitrile content is 20-50% by weight, Mooney viscosity MLl + 4100
℃, 15 to 150 is desirable.

Component F contributes to improving the oil resistance of the composition.

(G) Metal oxide, metal chloride (crosslinking agent) Examples of the metal oxide include zinc oxide, magnesium oxide, lead oxide, calcium oxide, etc., and zinc oxide is preferable.

Examples of metal chlorides include zinc chloride and tin chloride. In addition, for rounding to prevent corrosion of molds etc. due to free halogen,
It is desirable to use magnesium oxide together as a scavenger (hereinafter referred to as component C).

The usage amount of C component is M component, B component, C component, D component,
E component and? The content of the component is preferably 2 to 10 parts by weight, more preferably 1 to 5 parts by weight.

(ton) polyolefin ethylene, propylene, 1-butene, 1-pentene, 1
- Homopolymers of α-olefins such as hexene and 4-methyl-1-pentene, or copolymers of ethylene and α-olefins, or copolymers of two or more of these α-olefins, or ethylene or these α-olefins. Examples include vinyl esters containing as a main component, copolymers with unsaturated carboxylic acids or derivatives thereof, and the like. Here, the copolymer includes a random or block copolymer. VFR of these polyolefins (19D
C (260° C. for propylene polymers) is preferably I11 to 20 f/10 min for ethylene polymers, and 15 to 60 f/710 min for propylene polymers. Further, two or more of these polyolefins can be used in combination.

Among the above polyolefins, low-density polyethylene, linear low-density polyethylene, medium-density or high-density polyethylene, polypropylene, or random or block copolymers containing propylene as a main component are desirable. Further, the above-mentioned polyolefin can be completely mixed with an olefin-based elastomer, such as evaporated ethylene-propylene rubber, ethylene-propylene-diene copolymer rubber, etc. (hereinafter referred to as HJli3C).

In the composition obtained according to the present invention, component H improves fluidity and paintability without impairing rubber elasticity. In addition, since the H component has the same function as the above-mentioned M component, it can be blended with the A component to complement each other. However, the effect of blending component H can only be obtained by blending it into the above-mentioned composition in which the halogenated butyl rubber is completely crosslinked, and even if it is blended into compositions with other combinations, such effects cannot be obtained. cannot be obtained.

In addition to the above ingredients, stabilizers such as anti-breathing agents, ultraviolet absorbers, and metal deterioration inhibitors, lubricants, antistatic agents, electrical property improvers, flame retardants, and processability improvers may be added as necessary. , additives such as pigments, Merck, Tanshun calcium, barium sulfate,
All inorganic fillers such as mica and calcium silicate can be blended.

Blending ratio The blending ratio of the AI component, B component, C component, D component, E component and F component in the present invention is 10 to 90 parts by weight for the Aff component, preferably 20 to 70 parts by weight, 90 to 10 parts by weight for the B component, Desirably 30 to 80 parts by weight (however, select so that component A + component B = 100 parts by weight, component C 10 to 1 part by weight)
20 parts by weight, preferably 10 to 100 parts by weight, component D 5
~120 parts by weight, preferably 5 to 100 parts by weight, E component 1 to 901 parts by weight, preferably 5 to 50 parts! Volume and 1F
The amount of the component is 2 to 100 parts by weight, preferably 5 to 90 parts by weight. In addition, the C component (crosslinking agent) is the above-mentioned - F component 100
It is preferable that the amount of component A exceeds 90 parts by weight, the hardness and compression set will be large, and the elastomer properties will be impaired.

Furthermore, if the amount of component 0 is less than 10 parts by weight, the flexibility will be low and the molding fluidity will be poor. In addition, the compatibility between the mu component and the B component becomes poor. On the other hand, if the C component exceeds 120 parts by weight, the mechanical strength decreases and the compression set increases, which is not preferable.

``! f'-s If the D component is less than sxi parts, the flexibility will be insufficient, while if it exceeds 120 parts by weight, the mechanical strength will decrease and the product will become sticky, which is undesirable.

If the amount of each component is less than 1 part by weight, the compatibility of each component will be insufficient and mechanical strength will not improve.

On the other hand, the ■ component is 90-! If the amount is exceeded, no further effect can be expected and it is uneconomical.

Further, if the F component is less than 2 parts by weight, the oil resistance and heat resistance will not be improved, while if it exceeds 100 parts by weight, the fluidity of the composition will decrease, which is not preferable.

In addition, G component (H to the material to be kneaded in the presence of crosslinking agent 2)
Component (polyurethane) The amount of polyurethane blended is preferably 20 to 200 parts by weight, more preferably 40 to 70 parts by weight, per 100 parts by weight of the material to be kneaded. If the H component is less than 20 parts by weight, fluidity and coating On the other hand, the improvement in sex is insufficient.
If it exceeds 200 parts by weight, the flexibility and rubbery properties of the resulting mg product will be impaired, which is not preferable.

Method for producing composition The composition of the present invention is prepared by first preparing component A, component B, component C, and DI.
iy, minute, ff1g minute,? The components, the crosslinking agent (metallic compound and/or metal chloride), and other components if necessary are heated and melted and kneaded. The crosstalk may be carried out at a temperature at which each component melts, usually from 160 to 250°C, preferably from 170 to 220°C, for 1 to 10 minutes, preferably 5 to 5 minutes. By doing this, it is possible to produce a kneaded composition in which only the dispersed BE component is selectively crosslinked.

The melt mixing is carried out using a commonly used pressure kneader, Banbury mixer, screw extruder, or the like. (First step 2) Next, the composition to be kneaded and the H component obtained above are uniformly blended. As a method for uniformly blending the composition to be kneaded and the H component, both of the compositions to be kneaded and the H component can be blended uniformly. ,
After pre-mixing with a ribbon blender etc., extruder,
Examples include a method of melt-kneading using a Banbury mixer 1 pressure kneader or the like. At this time, various stabilizers, colorants, and inorganic fillers may be added as necessary. (Second step) In the production of the above composition, the E component and the F component are:
It can be blended in the first step, the wc2 step, or both.

Effects of the Invention Since the component B is partially crosslinked, the composition of the present invention has excellent compatibility, high mechanical strength without loss of rubber properties, and improved surface scratch resistance. It is. In addition, the blending of modified polyolefin increases the affinity of each component and improves impact resistance, and the blending of nitrile rubber improves oil resistance and heat resistance. In addition, the uniform blending of the H component (polyurethane) provides good paintability and fluidity, making it possible to obtain large molded products with a good appearance without flow marks or sink marks.

Second, the crosslinking agent used in the production of the composition is safer than organic peroxides. Since it is thermally stable, the degree of crosslinking can be adjusted as desired. Therefore, there is no breakage of the molecular chain of boriflovirene, no lowering of the molecular weight, and no deterioration of the coating properties or physical properties of the composition.

Furthermore, there are no residual free radicals caused by organic peroxides, and the heat resistance is good. In addition, despite the above improvements, it is cheaper than polyurethane products and can have mechanical properties and a high-class appearance similar to those of large polyurethane molded products.

The composition of the present invention can be easily molded by conventional thermoplastic resin molding methods, such as blow molding, extrusion molding, and injection molding.

The composition of the present invention has an excellent balance of flexibility, strength, and heat resistance, and has good moldability.
Suitable for materials such as spoilers and dampers.

Example Hereinafter, the present invention will be explained in detail using examples.

In addition, parts and parts in the examples are based on weight, and the test method is as follows.

TI) MFR: 7210 (load 2.16
(2) M work: J work EIK7210 (load 2.16 °C)
(190℃) (3) Tensile strength at break, tensile elongation at break: J-KEIK
(4) Flexural modulus: 7205 for J-technical 8 (5) Izotsu impact strength: 7110 for J-technical 8 (6) Shore hardness: J-technical 81C7215 (D-method (7) Heat deformation temperature test: J-technical 5K7207 (8) Bottom shape: ■ Molding conditions Injection molding machine Mitsubishi Natco 550MVXL40
Injection molding temperature 250℃ Injection pressure -Next pressure 800kg/i Secondary pressure 50
0kp/I:rI? Injection time: 13 seconds Bottom cycle 58 seconds Gate Side gate molded product 5X100X550-flat plate■ Judgment criteria flow mark ○: No occurrence Δ: Very slight occurrence ×: Significantly, many sink marks O: No occurrence Δ: Extremely low Watermark generation ×: Significantly increased glossiness Measured on J-engineering 8 using the 7105 method on the 60°fR surface.

O: Gloss retention 50% or more Δ: Gloss retention 10-50%
A primer [RB-291 (trade name) manufactured by Nippon B Chemical Co., Ltd.] was applied and baked at 80° C. for 30 minutes. Next, a top coat of paint [Flexene-101 (trade name: IT, manufactured by Nippon Paint Co., Ltd.) was applied thereto, and baked at 120° C. for 30 minutes.

■ Plasma method After cleaning the test piece with trichloroethane vapor for 1 minute,
Plasma treatment (argon plasma, 1.OkWX 1
．． Otorr
Bake for 30 minutes at 0°C next.

■ Evaluation Value Initial adhesion: Based on a cross-cut test of J-8 and 5400.

Hot water resistance: Appearance and cross-cut test after 240 hours immersion in 40°C hot water.

(7) Oil resistance: K6501 from J, J Engineering S5, immersed in oil, all those with swelling less than 50 inches are ◎, those with swelling of 50 or more and less than 100 inches are Δ, those with tO1 swelling of 100% or more and less than 200%, swelling 200 % or more were marked with ×.

Examples 1 to 14, Comparative Example 1.2 Materials used: Propylene-ethylene block copolymer (MF
R50 9710 minutes, ethylene content 7%, hereinafter PP
It's called Block-1.

Bg content: Chlorinated inbutylene-isoprene copolymer rubber (Mooney viscous K ML 10 g 100° C. 50, chlorine content 1%, degree of unsaturation 2 molt, hereinafter referred to as CAE R).

OX: Ethylene-propylene-ethyl IJ f7/
Lubornene copolymer rubber (Mooney viscosity ML, Tobata 12
7° C. 230, iodine value 18, ethylene content 60%, hereinafter referred to as EPDM-j).

D component: naphthene thread process oil < viscosity y - specific gravity constant α
880, hereinafter referred to as a softener.

K component: maleic anhydride modified product of propylene-ethylene block copolymer (acid addition iα5-1 or less CMPP
), maleic anhydride modification of high-density polyethylene'
m<acid addition iiα5ch, hereinafter referred to as OMHDPE)
, maleic anhydride modified product of low density polyethylene (acid addition-11Q, 5%, hereinafter referred to as CMLDPK,!),
Maleic anhydride modified product of ethylene-propylene rubber (acid addition amount α3, hereinafter referred to as CMEPR).

F component: Acrylonitrile-butadiene copolymer rubber (
Mooney viscosity MLl+4100℃ 56, contains acrylonitrile! 35% (hereinafter referred to as NBR).

G component: zinc dioxide, magnesium oxide (halogen scavenger).

HIlillC content: Propylene-ethylene block copolymer (MFR40f710min, ethylene content 7%, hereinafter referred to as PP block-2), high density polyethylene (density (L 945 f/ctn3, MI (LS5t/
10 minutes, hereinafter referred to as HDPK],]ethylene-7
Lopylene-etheridennorbornene copolymer rubber (Mooney viscosity [M'L +-127℃45, iodine value 3, ethylene content 65%, hereinafter referred to as EPDM-2], ethylene-propylene rubber (Mooney viscosity "Lx' 4100℃
24, ethylene content 73%, hereinafter referred to as 1nPR).

Other ingredients: Talc (average particle size 2.5μ).

Manufacture of the composition The above components except component H are blended in the proportions shown in Table 1, and 2 parts by weight of zinc oxide and 5 parts by weight of 1L of magnesium oxide are blended with respect to 100 weight of each mixture.
After melt-kneading at 170° C. for 5 minutes in a Banbury mixer, the mixture was cut into sheets and pelletized. (First step) Next, the H component and other components were blended with each pellet obtained in the first step in the proportions shown in Table 1, and after premixing in a Henschelmi medium, a twin screw extruder was used. The target composition was obtained by extruding at 200° C. (Second Step) The characteristics of each composition are shown in Table 1.

Claims (1)

[Claims] (A) 10 to 90 parts by weight of polypropylene, (B) 90 to 10 parts by weight of halogenated butyl rubber ((A) + (B)
) = 100 parts by weight), (C) olefin rubber 10-1
20 parts by weight, (D) 5 to 120 parts by weight of mineral oil softener, (
E) A mixture consisting of 1 to 90 parts by weight of modified polyolefin and (F) 2 to 100 parts by weight of nitrile rubber,
) An olefin-based soft resin composition obtained by heating, melting and kneading in the presence of a metal oxide and/or metal chloride, and then uniformly blending (H) polyolefin into the kneaded material.