JPH0575337A - Molding material for antenna reflector - Google Patents

Abstract

(57) [Abstract] [Purpose] A rubber material that satisfies various performance requirements for antennas, such as weather resistance, coating properties for conductive coatings for radio wave reflection, and reflector surface dimensional accuracy after injection molding and hollow molding. Provided is a molding material made of a reinforced thermoplastic resin. [Structure] A rubber-reinforced thermoplastic resin composed of AES resin, or AES resin and AS resin, having a graft ratio of 20 to 90% by weight and a vinyl cyanide content of 10.
.About.40% by weight, the intrinsic viscosity of the acetone-soluble component is 0.3 to 0.
7 dl / g, rubber content 10 to 35% by weight, and a fatigue strength retention rate of 70% or more after 2000 hours of irradiation in a sunshine carbon arc lamp type weather resistance test, molding material for antenna reflector ..

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to an antenna reflecting mirror such as a parabolic antenna which is required to have sufficient reflecting characteristics under a long-term outdoor environment where wind pressure is repeatedly applied. The present invention relates to a molding material made of a rubber-reinforced thermoplastic resin which has excellent paintability for paints and excellent surface dimension accuracy of a reflecting mirror after injection molding or hollow molding.

[0002]

2. Description of the Related Art For antenna reflectors such as parabolic antennas, a laminated body consisting of a thermosetting resin layer reinforced with glass fiber or the like and a metal layer was the mainstream at first, but due to remarkable development of satellite broadcasting, weight reduction, In addition to lowering the price and shortening the production cycle, sufficient reflection characteristics have been required. Under these circumstances, miniaturization has become possible due to the improvement of the receiving function, and at present, a method of applying a conductive coating material to the reflecting mirror surface of an injection-molded thermoplastic resin molded article to obtain a reflective characteristic is being studied. However, in the case of olefinic thermoplastic resins, pretreatment with a primer or the like is necessary because of poor coating properties for conductive paints, and dimensional accuracy is difficult due to shrinkage after molding, resulting in poor reflection characteristics. There is a drawback to Even a polyphenylene ether or styrene-based thermoplastic resin has a drawback that ABS resin has poor weather resistance and durability cannot be maintained unless the portion other than the conductive coating application surface is protected by coating. Therefore, at present, it is difficult for these thermoplastic resins to meet the demand.

[0003]

SUMMARY OF THE INVENTION According to the present invention, in order to meet the performance requirements of these antennas, a rubber excellent in weather resistance, coatability with a conductive coating for radio wave reflection, and excellent dimensional accuracy of the reflecting mirror surface after injection molding or hollow molding. It is to provide a molding material made of a reinforced thermoplastic resin.

[0004]

The present invention provides the following G-
1, or a rubber-reinforced thermoplastic resin composed of G-1 and G-2, having a graft ratio of 20 to 90% by weight, a vinyl cyanide content of 10 to 40% by weight, and an intrinsic viscosity of an acetone-soluble component. 0.3-0.7 dl / g, rubber content 10
The present invention provides a molding material for an antenna reflector, which has a fatigue strength retention of 70% or more after irradiation of 2000% in a sunshine carbon arc lamp weather resistance test at 35% by weight. G-1: In the presence of at least one polymer selected from the group consisting of ethylene-α-olefin-based copolymers, hydrogenated products of conjugated diene-based copolymers and acrylic rubbers, aromatic vinyl and / Alternatively, a graft copolymer obtained by polymerizing a monomer composed of (meth) acrylic acid ester and vinyl cyanide. G-2: Polymer of (meth) acrylic acid ester, and / or at least two copolymers selected from the group of aromatic vinyl, (meth) acrylic acid ester and vinyl cyanide.

The present invention will be described in detail below. The rubber-like polymer used in the rubber-reinforced thermoplastic resin of the present invention is an ethylene-α-olefin-based copolymer, a hydrogenated product of a conjugated diene-based polymer (hereinafter referred to as a hydrogenated diene-based polymer) or an acrylic-based polymer. It is at least one selected from the group of rubber. Among these, examples of the ethylene-α-olefin copolymer include ethylene-α-olefin copolymer rubber and ethylene-α-olefin-non-conjugated diene copolymer rubber. Examples of the α-olefins used here include 1-butene, 2-butene, propylene and the like, with propylene being preferred. With ethylene in these ethylene-α-olefin-based copolymers,
The composition ratio of α-olefin is preferably ethylene 35.
˜85 mol%, α-olefin 15 to 65 mol%, more preferably ethylene 50 to 80 mol%, and α-olefin 20 to 50 mol%. As the non-conjugated diene that can be copolymerized in a small amount, for example, ethylidene norbornene,
4,7,8,9-tetrahydroindene, cyclopentadiene, 1,4-hexadiene, propenyl norbornene, methylidene norbornene and the like can be mentioned.

The hydrogenated diene polymer is a hydrogenated product of a diene polymer such as polybutadiene, polyisoprene, styrene-butadiene random copolymer, acrylonitrile-butadiene copolymer and styrene-butadiene block copolymer. Is. Here, examples of the aromatic vinyl compound used for the diene polymer include styrene and t-
Butylstyrene, α-methylstyrene, p-methylstyrene, vinylxylene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromostyrene, fluorostyrene, pt-butylstyrene, ethylstyrene, vinylnaphthalene, divinylbenzene, 1,1-
Diphenyl styrene, N, N-diethyl-P-aminoethyl styrene, vinyl pyridine, etc. are mentioned, Especially,
Styrene and α-methylstyrene are preferred. Further, as the conjugated diene, 1,3-butadiene, isoprene,
2,3-dimethyl-1,3-butadiene, 1,3-pentadiene, 2-rutyl-1,3-pentadiene, 1,3
-Hexadiene, 4,5-diethyl-1,3-octadiene, 3-butyl-1,3-octadiene, chloroprene and the like can be mentioned, but a hydrogenated diene polymer which can be industrially used and has excellent physical properties can be used. In order to have it, 1,3-butadiene, isoprene, and 1,3-pentadiene are preferable, and 1,3-butadiene is more preferable.

The content of the aromatic vinyl compound in the diene polymer is preferably 60% by weight or less, more preferably 40% by weight or less, and 40-50% when the aromatic vinyl compound is an essential component. % By weight. If it exceeds 60% by weight, the hydrogenated diene polymer will have resin properties,
Impact resistance decreases. In the microstructure of the diene polymer, the vinyl bond content of 1,2-, 3,4-, etc. is preferably 5% by weight or more, and more preferably 10 to
80% by weight, particularly preferably 15 to 60% by weight. If this proportion is less than 5% by weight, the resulting hydrogenated diene polymer will have resin properties and the impact resistance of the finally obtained rubber-reinforced thermoplastic resin will decrease, which is not preferable.

The diene polymer before hydrogenation used in the present invention is a block copolymer or a random copolymer, for example, A: vinyl aromatic polymer block B: conjugated diene polymer block A / B Random polymer block of vinyl aromatic compound / conjugated diene C: Tapered block composed of polymer of conjugated diene and vinyl aromatic compound and gradually increasing vinyl aromatic compound. Sent. (1) A-B (2) A-B-A (3) A-B-C (4) A-B ₁ -B ₂ (5) B (6) A / B (7) A-A / B (8) a-a / B -C (9) a-a / B-a (10) B 2 -B 1 -B 2 ( wherein, B _1, B ₂ have the same meanings) (11) C- B (12) C-B-C (13) C-A / B-C (14) C-A-B

The vinyl aromatic compound / conjugated diene ratio of these block copolymers or random copolymers is preferably 5-60 / 95-40, more preferably 10-50 / 90-50 by weight ratio. Is. here,
When the content of the vinyl aromatic compound exceeds 60% by weight, the vinyl aromatic compound becomes a resin and the resulting rubber-reinforced thermoplastic resin has a low impact resistance. The bond content of the vinyl aromatic compound in the block A and the taper block C in the total monomers is preferably 3 to 25% by weight, more preferably 5 to 20% by weight, and the content is less than 3% by weight. On the other hand, the coloring property of the composition is lowered, while when it exceeds 25% by weight, the composition becomes resinous and the impact resistance of the obtained rubber-reinforced thermoplastic resin is lowered. Further, the vinyl bond content of the conjugated diene moiety in the block copolymer or the random copolymer is preferably 15 to
It is 65% by weight, more preferably 20 to 60% by weight, and particularly preferably 25 to 50% by weight. If it is less than 15% by weight, the structure after hydrogenation will be close to that of polyacetylene, and the impact when used as a rubber-reinforced thermoplastic resin. On the other hand, the strength is lowered, and on the other hand, when it exceeds 65% by weight, the rubber-like property is lost after hydrogenation, so that the impact strength is also lowered, which is not preferable. Moreover, the thing which the terminal of said (1)-(3), (4), (10) was coupled by the coupling agent is also mentioned.

The acrylic rubber is a homopolymer of (meth) acrylic acid ester, or a copolymer of (meth) acrylic acid ester with other vinyl-based monomers and halogen-containing monomers, and It has a glass transition temperature of 0 ° C. or lower. The (meth) acrylic acid ester is preferably ethyl acrylate, butyl acrylate, 2-
Other preferable vinyl-based monomers such as ethylhexyl acrylate include acrylonitrile, and preferable halogen-containing monomers include 2-chloroethyl vinyl ether. A preferable rubber-like polymer is an ethylene-α-olefin rubber hydrogenated diene copolymer.

The vinyl monomer used in the graft copolymer (G-1) and the copolymer (G-2) will be described. Examples of the vinyl aromatic compound include styrene, t-butylstyrene, α-methylstyrene, p-methylstyrene, vinylxylene, monochlorostyrene, dichlorostyrene, monobromostyrene, dibromostyrene, fluorostyrene, pt-butyl. Examples thereof include styrene, ethylstyrene, vinylnaphthalene, divinylbenzene, 1,1-diphenylstyrene, N, N-diethyl-P-aminoethylstyrene, vinylpyridine, and the like. These are used alone or in combination of two or more. Be done. Preferred are styrene and α-methylstyrene. (Meta)
Examples of acrylic acid esters include methyl acrylate, ethyl acrylate, propyl acrylate, butyre acrylate, amyl acrylate, hexyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, cyclohexyl acrylate, dodecyl acrylate, octadecyl acrylate, phenyl acrylate, and benzyl acrylate. Acrylic ester of methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, amyl methacrylate, hexyl methacrylate, octyl methacrylate, 2-ethylhexyl methacrylate, cyclohexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, phenyl methacrylate, benzyl methacrylate Methacrylic acid esters of laser and the like, and is used in one or more. Preferred is methyl methacrylate.

The vinyl cyanide compound may, for example, be acrylonitrile or methacrylonitrile, which may be used alone or in combination. If necessary, other copolymerizable monomers can be copolymerized. For example,
Unsaturated acid anhydrides such as maleic anhydride, itaconic anhydride and citraconic anhydride; unsaturated acids such as acrylic acid and methacrylic acid; maleimide, N-methylmaleimide, N-butylmaleimide, N- (p-methylphenyl) Examples include α- or β-unsaturated acid dicarboxylic acid imide compounds such as maleimide, N-phenylmaleimide and N-cyclohexylmaleimide; epoxy compounds such as glycidyl methacrylate; unsaturated acid carboxylic acid amides such as acrylamide and methacrylamide. .. These other copolymerizable monomers may be used alone or in combination of two or more.

The rubber-reinforced thermoplastic resin of the present invention comprises the following G-1, or G-1 and G-2. G-1: In the presence of at least one polymer selected from the group consisting of ethylene-α-olefin-based copolymers, hydrogenated products of conjugated diene-based copolymers and acrylic rubbers, aromatic vinyl and / Alternatively, a graft copolymer obtained by polymerizing a monomer composed of (meth) acrylic acid ester and vinyl cyanide. G-2: Polymer of (meth) acrylic acid ester, and / or at least two copolymers selected from the group of aromatic vinyl, (meth) acrylic acid ester and vinyl cyanide. In the present invention, the graft ratio of G-1, rubber-like polymer content, monomer composition ratio, intrinsic viscosity, G
-2, the proportion of the monomer composition, the intrinsic viscosity, etc. are not specified, but the graft ratio of the rubber-reinforced thermoplastic resin obtained from G-1 or G-2, the rubber-like polymer content, the monomer Since the composition ratio and the intrinsic viscosity are determined, G-1 and G-2 are appropriately adjusted to achieve them.
Examples of the polymerization method of G-1 and G-2 include emulsion polymerization, solution polymerization, bulk polymerization and suspension polymerization.

The following items are listed as the performance required as a molding material for the antenna reflecting mirror. (1) Excellent coatability with respect to a conductive coating for radio wave reflection. If there is no coating surface defect such as suction or craze and a uniform coating film is not formed, high radio wave reflection accuracy cannot be maintained. Further, if the adhesiveness to the reflecting mirror material is low, the coating film may be peeled off and the radio wave reflection function itself cannot be maintained. Therefore, excellent coatability is one of the important performances. (2) The reflecting mirror surface has excellent dimensional stability and smoothness. Excellent surface smoothness and dimensional stability are important performances for maintaining high radio wave reflection accuracy. (3) Excellent weather resistance. Since the reflecting mirror is exposed to the environment in which it is repeatedly subjected to wind pressure load for a long period of time, it is required to have excellent weather resistance.

When a material that deteriorates due to weathering is used, it is necessary to protect the portion other than the surface coated with the conductive paint by coating.
If it is a weather resistant material, it is possible to omit the coating protection, and the cost can be reduced accordingly. Regarding (1), the vinyl cyanide content, the acetone-soluble content, and the graft ratio are
For (2), the graft ratio, acetone-soluble content, and rubber content, and for (3), the fatigue strength retention rate after 2000 hours of the sunshine carbon arc lamp weather resistance test. Each can be satisfied by stipulating in. The graft ratio of the rubber-reinforced thermoplastic resin of the present invention is 20 to 90% by weight, preferably 3
It is 0 to 80% by weight, and if it is less than 20% by weight, the coatability and impact resistance may be poor, and if it exceeds 90% by weight, the coatability may be poor. The vinyl cyanide content is 10 to 40% by weight, preferably 15 to 35% by weight, and if it is less than 10% by weight or exceeds 40% by weight, the coatability is poor. The intrinsic viscosity of the acetone-soluble component is 0.3 to 0.7 dl / g, preferably 0.4 to 0.6 dl / g. If it is less than 0.3 dl / g, the impact resistance is poor, and if it exceeds 0.7 dl / g, the coating property is poor. The rubber content is 10 to 35% by weight, preferably 1
It is 5 to 30 weight. If it is less than 10% by weight, impact resistance is poor, and if it exceeds 35% by weight, dimensional stability is poor.

In the sunshine carbon arc lamp type weather resistance test, the fatigue strength retention rate after irradiation for 2000 hours was 70.
% Or more, preferably 80% or more. If it is less than 70%, there is a strong possibility that cracks will be generated or destroyed during long-term use, and it is necessary to protect the paint. To adjust the graft ratio of G-1, the type and amount of initiator,
It is carried out by a generally known method such as polymerization temperature and addition time of monomers. The intrinsic viscosity of G-1 and G-2 is adjusted by a generally known method such as the type / amount of the initiator, the type / amount of the molecular weight modifier, and the polymerization temperature. The fatigue strength retention rate after 2000 hours of irradiation in the sunshine carbon arc lamp type weather resistance test can be adjusted by the type of G-1 rubber, the type and amount of ultraviolet absorber, light stabilizer and the like.

There are no particular restrictions on the types of organic stabilizers such as ultraviolet absorbers and light stabilizers that can be blended with the rubber-reinforced thermoplastic resin of the present invention, but there are no particular restrictions, but phenol-based, sulfur-based, phosphorus-based, amine One or two or more selected from the group consisting of benzophenone series, benzophenone series, salicylate series, benzotriazole series, hydrazine series and epoxy series are used. In particular, 1 of phenol, sulfur and phosphorus
When used in combination with one or two or more of amine-based, benzophenone-based, salicylate-based, hydrazide-based, and benzotriazole-based compounds, or two or more of them, the effect against heat and light becomes large, and weather resistance is improved. Can be made The total amount of these additives added varies depending on the composition and components of the resin composition, but is generally 0.01 to 3 parts by weight per 100 parts by weight of the resin composition.

Here, the intrinsic viscosity ([η]) is determined by drying the acetone-soluble component of the rubber-reinforced thermoplastic resin, dissolving 0.25 g in 50 ml of dimethylformamide, and flowing out at 30 ° C. using a viscous tube. It is a value calculated by the following formula after measuring the time. [Η] = [− 1+ (1.4 × t ₁ / t ₀ −0.4) ^1/2 ] / (0.7 × C) In the formula, t ₁ ; outflow time (second) t in the sample solution t ₀ : Outflow time in blank solution (seconds) C: Solution viscosity (%) The specific method of obtaining this grafting ratio is to first add 2 g of the rubber-reinforced thermoplastic resin to acetone at room temperature, and sufficiently stir it.
Determine the insoluble matter (w). On the other hand, the amount of the rubber-like polymer in the insoluble matter (w) can be calculated based on the polymerization prescription. Let R be the calculated amount of the rubber-like polymer, and obtain the graft ratio from the following formula. Graft ratio (% by weight) = [(w−R) / R] × 100 In addition to the rubber-reinforced thermoplastic resin of the present invention, a hindered phenol-based, phosphorus-based, and sulfur-based antioxidant or lubricant, Additives that are commonly used, such as reinforcing agents such as whiskers and glass fibers, and fillers can be added.

In the present invention, the method of manufacturing the antenna is not particularly limited, but for example, a method of laminating a metal layer for radio wave reflection or a method of applying a conductive paint on the molding material specified in the present invention. And the like. By using the molding material specified in the present invention, an antenna having a desired shape can be manufactured. The antenna can be manufactured in various shapes such as a circular shape and a rectangular shape, and can also be manufactured in a flat shape or a curved shape. As a molding method, it can be molded by ordinary injection molding, but by adding a foaming agent to form a low foam, or by injecting gas during injection molding,
There are few sink marks and warps by performing blow molding,
It is possible to manufacture a reflecting mirror having high electromagnetic reflection efficiency. Further, the present invention can be used for a reflecting mirror accessory such as a converter box other than the reflecting mirror.

[0020]

EXAMPLES The present invention will be described in more detail below with reference to examples.
Explained. In the examples, parts and% are not specifically mentioned.
Unless stated otherwise. Also, various evaluations in the examples
Is a value measured as follows. <Weather resistance> Sunshine carbon arc lamp weather resistance test Black panel temperature; 63 ° C Rain cycle; 18 minutes / 120 minutes Light irradiation time; 2000 hours <Fatigue strength> Type of load stress; Piece (injection molding); width 20mm x length 150mm x thickness 3
mm (with V-shaped notches on both ends in the center in the length direction) The fatigue strength retention rate in the present invention is a value calculated from the following equation.
Is. Fatigue strength retention rate [%] = S₁/ S₀× 100 S₁; Fatigue strength after 2000 hours of weather resistance test * (Kg / mm
²) S₀Initial fatigue strength [kg / mm²] (* Fatigue strength; Number of repetitions: 10⁷Destroyed even if the number of times reached
No stress. ) <Paintability> Using a conductive paint with a silver powder content of 35%
Good appearance, good adhesion strength, ○ bad
It was judged. <Smoothness and dimensional stability of the surface of molded products>
Outside the molded product obtained by injection molding using the attached mold.
Appearance is visually evaluated, and smooth ones stand out such as sink marks.
The thing was judged as x.

Reference Example 1 (Method for producing hydrogenated block copolymers (a to d, a to f) which are rubber components of a hydrogenated diene polymer) [hydrogenated block copolymer a] 5 liter autoclave After charging 2500 g of degassed and dehydrated cyclohexane and 25 g of styrene, 9.8 g of tetrahydrofuran
And 0.2 g of n-butyllithium were added, and isothermal polymerization was carried out at a polymerization temperature of 50 ° C. (first stage polymerization). After the conversion reached about 100%, polymerization was carried out at a temperature of 70 ° C. while continuously adding a mixture of 300 g of 1,3-butadiene and 75 g of styrene at a rate of 75 g per 10 minutes (second step). Stage polymerization). 100% conversion rate
50g of 1,3-butadiene and 50g of styrene
The mixture of g was added all at once, and adiabatic polymerization was performed (third stage polymerization). Sampling was carried out for 5 minutes during the polymerization to measure the styrene content and the 1,3-butadiene cyclo structure in the sequentially produced polymer. After the conversion reached almost 100%, the reaction solution was cooled to 70 ° C., 0.6 g of n-butyllithium, 0.6 g of 2,6-di-tert-butyl-P-cresol, and bis (cyclopentadiene). 0.28 g of (enyl) titanium dichloride and 1.1 g of diethylaluminum chloride were added and the reaction was carried out for 1 hour while maintaining the pressure of 10 kg / cm ³ with hydrogen gas. The reaction solution was cooled to room temperature, desolvated by steam stripping, and then at 120 ° C.
It was dried by a roll to obtain a hydrogenated block copolymer a.
The molecular characteristics of the hydrogenated block copolymer a thus obtained are shown in Table 1.

Reference Example 2 (Graft copolymers G-1a to G
Adjustment of -1f) An autoclave having an internal volume of 10 liters was charged with the rubber-like polymer shown in Table 2, styrene and 130 parts of toluene, and stirred at a temperature of 50 ° C until the rubber-like polymer was completely dissolved. Then, acrylonitrile, t-, shown in Table 2
After addition of dodecyl mercaptan (variable between 0.1 and 0.5 parts), t-butylperoxyisopurupyl carbonate (variable between 0.2 and 0.8 parts), 80
The polymerization reaction was carried out at a suitable temperature of ˜130 ° C. for a suitable polymerization time of 5 to 15 hours. The polymerization product was desolvated and dried by a conventional method, 0.4 part of 2,2-methylenebis- (4-ethyl-6-t-butylphenol) was added, and the mixture was pelletized using an extruder to obtain a graft copolymer. Polymer G-
1a to G-1f were obtained.

Examples 1 to 4 and Comparative Examples 1 to 3 The graft copolymers prepared in Reference Example 2 were mixed according to the formulation shown in Table 3, and the resin temperature was 23 using a vented extruder.
Pellets were produced by melt mixing at 0 ° C and extruding. Using the pellets, a sheet was prepared by a 30 mmφ extruder at a cylinder temperature of 220 ° C. and a mold temperature of 210 ° C., and each physical property was evaluated. Table 3 shows the results of Examples 1 to 4 and Comparative Examples 1 to 5. As is clear from Table 3,
Examples 1 to 4 are examples in which a rubber-reinforced thermoplastic resin within the scope of the present invention was used, and the molding material intended by the present invention was obtained. On the other hand, Comparative Examples 1 to 5 are examples outside the scope of the present invention and are inferior in any one of the fatigue strength retention rate after 2000 hours of weather resistance, coating property and smoothness, and dimensional stability.

[0024]

[Table 1]

[0025]

[Table 2]

[0026]

[Table 3]

[0027]

EFFECTS OF THE INVENTION The molding material comprising the rubber-reinforced thermoplastic resin of the present invention is excellent in weather resistance, coatability with respect to the conductive coating for radio wave reflection, and excellent dimensional accuracy of the reflecting mirror surface after injection molding or hollow molding. It exhibits extremely high performance for antenna reflectors that require sufficient reflection characteristics under the environment where wind pressure is repeatedly applied outdoors for a certain period.

Claims (1)

[Claims] 1. The following G-1, or G-1 and G-2
A rubber-reinforced thermoplastic resin having a graft ratio of 20 to 90% by weight and a vinyl cyanide content of 10 to 4
0% by weight, intrinsic viscosity of acetone-soluble component 0.3-0.7 dl
/ G, a rubber content of 10 to 35% by weight, and a fatigue strength retention rate of 70% or more after 2000 hours of irradiation in a sunshine carbon arc lamp weather resistance test, a molding material for an antenna reflector. G-1: In the presence of at least one polymer selected from the group consisting of ethylene-α-olefin-based copolymers, hydrogenated products of conjugated diene-based copolymers and acrylic rubbers, aromatic vinyl and / Alternatively, a graft copolymer obtained by polymerizing a monomer composed of (meth) acrylic acid ester and vinyl cyanide. G-2: Polymer of (meth) acrylic acid ester, and / or at least two copolymers selected from the group of aromatic vinyl, (meth) acrylic acid ester and vinyl cyanide.