JPH0550493A - Hollow molded product for engine peripheral mechanism part made of polyarylene sulfide resin - Google Patents

Abstract

PURPOSE:To obtain the hollow part for intake and exhaust in the periphery of a engine satisfying required properties such as mechanical physical properties, heat resistance, chemical resistance or wt. saving by subjecting a polyarylene sulfide(PAS) resin or a composition thereof to blow molding. CONSTITUTION:The viscosity of a PAS resin to be used (in the case of the compounding of two kinds of PAS resins, the viscosity of the compound of said resins) is desirably 2000-20000 poise under a condition of 310 deg.C and a shearing speed of 1200sec<-1>. It is pref. to compound 5-150 pts.wt. of a fibrous filler such as a glass fiber with 100 pts.wt. of the PAS resin. This compound is subjected to blow molding by a usual molding machine to make it possible to obtain an intake manifold. When an alkoxysilane compound is added to the resin material, the drawdown of a parison can be suppressed and, when an olefinic copolymer containing alpha, beta unsaturated glycidyl ester, especially, matter obtained by grafting a vinyl polymer or copolymer on said copolymer is added, molding is stabilized and the toughness of a molded product is enhanced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow component such as an intake manifold used for intake / exhaust or intake / exhaust liquid around an engine of an automobile. For more details,
It is intended to provide a hollow molded article made of a polyarylene sulfide resin or a composition thereof by a blow molding method for intake / exhaust gas or intake / exhaust liquid around an engine.

[0002]

2. Prior Art and Problems to be Solved by the Invention
Intake manifolds such as automobiles, intake air connectors, canisters, radiator tanks, surge tanks, reservoir tanks, and other hollow mechanical parts for intake / exhaust or intake / exhaust liquid around the engine are mainly cast of aluminum alloys, etc. In addition to high cost, the metal has drawbacks such as high weight and noise, and improvement thereof is earnestly desired. In this respect, thermoplastic resin materials are expected to be lighter in weight and lower in noise, and also expected to improve molding processing efficiency.
Plastic materials are generally not sufficient for such parts in terms of mechanical strength, heat resistance, chemical stability, etc.
Only some engineering plastics satisfy such physical properties. On the other hand, on the other hand, such a physically high-performance resin is, on the other hand, not suitable for the production of hollow molded products.
Due to the lack of melt tension, the most efficient blow molding method cannot be adopted, and the injection molding method must be used exclusively, and the injection molding method cannot mold a hollow body with a special shape at one time. However, it is necessary to join after split molding, and this method leaves a weak point at the joint and is not efficient. or,
There is a so-called alloy core method (a method in which a core of a low melting point alloy is set in the hollow part, insert molding is performed by injection molding, and then the core alloy is melted and removed to form the hollow part). Not only is it complicated, inefficient and uneconomical,
There is a limit to the thickness of the molded product, and it is not sufficient to reduce the weight. The present invention can employ a very efficient and economical blow molding method as a method for manufacturing a hollow body, and more than a certain level of physical properties capable of withstanding harsh conditions such as mechanical components for intake and exhaust or intake and exhaust liquid around the engine, In particular, a resin material having requirements such as mechanical strength, heat resistance, and chemical resistance is searched for, and an object thereof is to provide a hollow molded product for mechanical parts around the engine having the above requirements, such as an intake manifold. For this purpose, nylon resins and the like are currently tried, and blow molding is possible for the time being, but it has not yet been possible to mold sufficiently stably,
In reality, the physical properties are not sufficient for this purpose.

[0003]

Means for Solving the Problems The present inventors have solved the above problems and have a mechanical property, heat resistance, chemical stability, and other properties suitable for such applications, and are made of a lightweight thermoplastic resin. As a result of earnest studies to efficiently obtain the hollow molded article of 1. by a blow molding method, the use of a specific polyarylene sulfide (hereinafter abbreviated as PAS) resin or a composition thereof achieves this object and completes the present invention. Came to do. That is, the present invention is a hollow molded product for a mechanical component used around an engine, which is composed of a hollow portion molded by a blow molding method using a PAS resin or a composition thereof.

The resin material used in the present invention will be described below. The PAS resin used in the hollow molded article of the present invention is composed of a main repeating unit -Ar-S- (where -Ar- is an arylene group), and the arylene group (-Ar-) is, for example, p-phenylene group, m-phenylene group, o
-Phenylene group, a substituted phenylene group (wherein the substituent is an alkyl group, preferably a C _{1 to} C ₅ alkyl group, or a phenyl group), p, p'-diphenylene sulfone group, p, p'-biphenylene group, and p, p'-diphenylene ether group, p, p'-diphenylene carbonyl group, naphthalene group and the like. In this case, in the arylene sulfide group composed of the above arylene group, a polymer using the same repeating unit, that is, a homopolymer can be used, and from the viewpoint of processability of the composition, different repeating units are used. In some cases, the included copolymers are preferred. A typical example is a poly-p-phenylene sulfide (hereinafter referred to as PPS) resin having a p-phenylene sulfide group as a repeating unit and using a p-phenylene group as an arylene group. Further, as the copolymer, among the arylene sulfide groups consisting of the above-mentioned arylene groups, two or more different combinations can be used, but among them, a combination mainly containing p-phenylene sulfide groups and containing an m-phenylene sulfide group is preferable. Particularly preferably used. Among these, p-phenylene sulfide group
Those containing 60 mol% or more, more preferably 70 mol% or more are suitable from the viewpoint of physical properties such as heat resistance, moldability and mechanical properties. In this case, the repeating units of the components contained in a block form rather than a random form (for example, those described in JP-A-61-122828) have good processability, heat resistance and mechanical properties. It has excellent physical properties and can be preferably used. Such polymers are generally disclosed in JP-A-61-7.
332 or 61-66720, etc. That is, a substantially linear structure high molecular weight polymer obtained by polycondensation from a bifunctional monomer, or a branched or crosslinked structure obtained by polymerizing a small amount of a monomer having three or more functional groups as a part of the monomer together A PAS resin having the above or a compounded resin obtained by blending the PAS resin with the above linear polymer can also be used and is preferable. Among the above, the PAS resin used for molding the hollow part of the present invention has a substantially linear structure, a high molecular weight and a melt viscosity of at least 2000 poise (310 ° C., shear rate).
1200 sec ^-1 ) can be used, but it is particularly preferable to use a small amount (0.01 to 5 mol%) of a monomer (branching or crosslinking agent) having three or more functional groups in the polycondensation reaction. A PAS having a branched or crosslinked structure produced by the above process, or a mixture with a linear polymer containing at least 5% by weight or more of the PAS having such a branched or crosslinked structure. It is preferable in order to increase the height, suppress drawdown of the parison, and perform stable blow molding. The viscosity of such a polyarylene sulfide resin (as a blend in the case of blending two types of PAS) is 310 ° C. and a shear rate of 1200 sec ⁻¹ , at least 2000 poise or more and 20000 or more, preferably 2500 or more 150.
It is desirable to be less than 00. If the viscosity of the PAS resin is too low, drawdown of the parison is likely to occur during blow molding and the moldability becomes unstable, and if the viscosity is too high, the fluidity deteriorates and overload is not preferable.

The resin material used in the present invention is the above-mentioned PA.
It is possible to use only S resin, but by adding it to the composition with the following additives or fillers, it is possible to further improve the melt tension and stabilize blow molding, and for intake and exhaust for engines, etc. It is effective in improving the physical properties of the hollow mechanical component.

That is, as an additive effective for this purpose, there is an alkoxysilane compound, for example, an organic silane compound such as vinylalkoxysilane, aminoalkoxysilane, epoxyalkoxysilane, mercaptoalkoxysilane, etc., which increase the melt tension. Although it is effective in suppressing drawdown in blow molding and obtaining stable moldability, the addition amount is 5 parts by weight or less, preferably 0.01 to 3 parts by weight, relative to 100 parts by weight of the PAS resin.
If it exceeds 5 parts by weight, the thickening effect is remarkable and the moldability is adversely affected.

Next, as an effective additive, an olefin copolymer can be mentioned. Among them, olefin-based copolymers containing olefin and α, β-unsaturated glycidyl ester as essential components are effective, and particularly,
A graft copolymer in which a vinyl polymer or a copolymer is chemically bonded in a branched or cross-linked structure to the copolymer of α-olefin and α, β-unsaturated glycidyl ester is more effective. Examples of such olefin-based graft copolymers include trade name "Modeper A" manufactured by NOF CORPORATION
Various substances marketed as a series can be mentioned. Addition of such an olefin-based copolymer is also effective for improving melt tension and stabilizing blow molding, and is also effective for improving mechanical strength, particularly toughness, of a hollow molded article. However, if the compounding amount is too large, the viscosity is remarkably increased, which adversely affects the blow moldability, and also impairs the heat resistance and the chemical resistance of the material, which is not suitable for the purpose of the present invention. Therefore, the compounding amount of this substance is 30 parts by weight or less, preferably 0.5 to 20 parts by weight, based on 100 parts by weight of PAS resin.

Next, the PAS resin material used for blow molding of the present invention preferably further contains a fibrous filler. As the fibrous filler, glass fiber, asbestos fiber, carbon fiber, silica fiber, silica-alumina fiber, zirconia fiber, boron nitride fiber, silicon nitride fiber, boron fiber, potassium titanate fiber, stainless steel, aluminum, titanium, Inorganic fibrous substances such as metallic fibrous substances such as copper and brass can be used. A particularly representative fibrous filler is glass fiber. Such a fibrous filler is effective in improving the mechanical strength of the hollow molded article and imparting rigidity.

In addition to the fibrous filler, powdery or granular filler may be blended. As the powdery and granular filler, carbon black, silica, quartz powder, glass beads, glass powder, calcium silicate, aluminum silicate, kaolin, talc, clay, diatomaceous earth, silicates such as wollastonite, iron oxide, and oxidation. Titanium, zinc oxide, metal oxides such as alumina, calcium carbonate, metal carbonates such as magnesium carbonate, calcium sulfate, metal sulfates such as barium sulfate, other silicon carbide, silicon nitride, boron nitride,
Examples include various metal powders. Examples of the plate-like filler include mica, glass flakes, various metal foils and the like.

These inorganic fillers can be used alone or in combination of two or more. The combined use of fibrous fillers, especially glass fibers and powdery or granular or plate-like fillers is a preferable combination in terms of mechanical strength and dimensional accuracy of molded products, electrical properties, etc., and particularly improved blow moldability. It is also effective.
When using these fillers, it is desirable to use a sizing agent or a surface treatment agent. This example is a functional compound such as an epoxy compound, an isocyanate compound, a titanate compound, a silane compound.

The blending amount of the above-mentioned filler in the present invention is PA
The total amount is 150 parts by weight or less, preferably 2 to 100 parts by weight, based on 100 parts by weight of the S resin. If the blending amount is too small, the rigidity, strength, etc. tend to be low, and if it is too large, the fluidity is impaired, which is not preferable.

Further, in addition to the above, it is possible to supplementarily use a small amount of other thermoplastic resin in the PAS resin composition used in the present invention. Any other thermoplastic resin may be used as long as it is a thermoplastic resin that is stable at high temperatures. For example, an aromatic polyester such as a polyolefin (co) polymer other than the above, polyethylene terephthalate, polybutylene terephthalate, etc. and an aromatic polyester composed of a diol or an oxycarboxylic acid, a polyamide polymer, a polycarbonate,
Examples thereof include ABS, polyphenylene oxide, polyalkyl acrylate, polyacetal, polysulfone, polyether sulfone, polyetherimide, polyetherketone, and fluororesin. Further, these thermoplastic resins may be used as a mixture of two or more kinds.

Further, in the PAS resin of the present invention, known substances generally added to synthetic resins, that is, stabilizers such as antioxidants and ultraviolet absorbers, antistatic agents, flame retardants, coloring such as dyes and pigments, etc. Agents, lubricants, mold release agents, crystallization accelerators, crystal nucleating agents and the like can be appropriately added depending on the required performance.

The resin material used for blow molding of the present invention is melted and kneaded by adding the above-mentioned various additives to the above PAS-based resin, if necessary, and melted by adding other desired components in some cases. The melt-kneading of each component, which is kneaded and then blow-molded, may be pelletized once by using a single-screw or twin-screw extruder and then subjected to blow-molding, or immediately after melt-kneading It is also possible to use it as a parison for molding.

The blow molding of the present invention may be carried out by a usual method using a blow molding machine generally used for blow molding of thermoplastic resins. That is, the above PAS resin or its composition is plasticized by an extruder or the like, and this is extruded or injected by an annular die to form an annular melted or softened intermediate parison, which is sandwiched between molds to form an internal product. A gas is blown into the mixture to inflate it, and then cooled and solidified to form a hollow body. As the molding conditions for the PAS resin of the present invention, the cylinder and die temperatures are preferably 280 to 350 ° C, particularly preferably 290 to 320 ° C. The mold temperature is 40 ~
200 [deg.] C. is preferable, and 80 to 160 [deg.] C. is particularly preferable.
The gas blown into the inside may be air, nitrogen or the like, but air is usually used in consideration of economy, and the blowing pressure is preferably 4 to 10 kg / cm ² . Further, it can be molded by a special blow molding machine such as a three-dimensional blow molding machine.
It is also possible to make two or more layers of different PAS resins or compositions and, if necessary, combine with layers made of other materials to form a multilayer blow molding. For example, by forming a layer of PAS resin containing no filler such as glass fiber in the inner layer and using fiber reinforced PAS in the outer layer, it is possible to improve the smoothness of the inner surface of the hollow product and to maintain the strength. .. The PAS resin composition used for this inner layer may contain a filler (mineral, CaCO _3, etc.) that does not impair the surface smoothness, and the constitution of each layer may be appropriately selected depending on the purpose.

The present invention is characterized by forming a hollow portion for mechanical parts such as intake and exhaust around an engine such as an intake manifold by blow molding using a PAS resin or its composition. Other parts or parts made, for example, flanges or the like are joined by welding or the like to be used as an integrated part.

[0017]

EFFECTS OF THE INVENTION By using a PAS resin or a composition thereof as in the present invention, an automobile or the like which efficiently satisfies the requirements of mechanical properties, heat resistance, chemical resistance, weight reduction, etc. by a blow molding method. It is possible to provide a hollow mechanical component for intake / exhaust or intake / exhaust liquid around the engine, such as a hollow component such as an intake manifold.

[0018]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

Examples 1 to 4 and Comparative Example 1 Four kinds of PAS resin materials shown in A to D below and E (nylon type; comparative example) were used, and a resin temperature was 320 ° C. and a diameter was 300 m.
Extruded as an m (thickness 3 mm) parison, and then blown with air at a blow pressure of 5 kg / cm ² at the same time as the mold clamping (mold temperature 150 ° C.), and the model type of the intake manifold for automobile engine as shown in FIGS. , Made by blow molding,
The moldability and the properties of the molded product were evaluated. Further, the suitability of the material itself as a hollow mechanical component for engine intake and exhaust was evaluated by another test piece. The results are shown in Table 1. The resin material used and the evaluation method are as follows. Resin material A: 100 parts by weight of branched PPS (5000 poise) Pellets obtained by mixing and mixing 25 parts by weight of glass fiber B: 100 parts by weight of branched PPS (5000 poise) E / GMA (Note-1) 7 parts by weight Glass fiber 25 PPS pellets consisting of 10 parts by weight C: Branched PPS (5000 poise) 30% by weight and linear PPS (1500 poise) 70% by weight PPS (2700 poise) 100 parts by weight E / GMA-g-AS (Note -2) 15 parts by weight PPS pellets consisting of 45 parts by weight of glass fiber D: 100 parts by weight of linear PPS (2500 poise) Alkoxysilane (Note-3) 1 part by weight E / GMA-g-AS (Note-2) 5 parts by weight PPS pellets made of 45 parts by weight of glass fiber E: (Comparative example) Nylon 66 100 parts by weight Pellets made of 45 parts by weight of glass fiber Note-1: Ethylene-glycidyl methacrylate copolymerization Note -2: ethylene - glycidyl methacrylate to styrene-acrylonitrile copolymer graft copolymer obtained by grafting a body Note -3: .gamma.-aminopropyltriethoxysilane blow moldability Evaluation 1) In drawdown the blow molding of the parison Push the parison to a length of 400 mm, stop it, and measure the extension of the parison after 10 seconds due to its own weight. Fine within 420 mm, small between 420 and 460 mm, medium between 460 and 500 mm, 500 or more. Was defined as "large". 2) Breakage during blowing The breakage during blowing was visually determined. 3) Uniformity of wall thickness As shown in FIG. 2, a predetermined portion of the pipe portion was cut, and the difference between the maximum thickness portion and the minimum thickness portion was shown as a percentage of the average. 4) Appearance Cut the pipe part, observe the smoothness of the inside and outside,
In order of goodness, "Excellent", "Good", and "Fair" were ranked. Physical property test 5) Heat resistance The test piece is left at 170 ℃ for 1000 hours, and the tensile strength and elongation before and after that are measured, and the retention rate (%) before treatment (100)
showed that. 6) Dynestat impact test Shows the retention rate of Dynestat impact strength after immersion in 50% ethylene glycol solution at 120 ° C for 100 hours. 7) Steam resistance test Shows the retention rate of tensile strength and elongation after standing in steam at 130 ° C for 1000 hours. 8) LLC (Long Life Coolant) resistance test 170 degreeC, it immersed in the LLC undiluted solution for 100 hours, bending strength and the same elastic modulus were measured, and the retention rate was calculated | required. 9) CaCl ₂ resistance test After soaking the test piece for 24 hours in boiling water, add 5% CaCl ₂
An aqueous solution was applied, and this was left under constant (60 kg / cm ² ) stress for 1 hour at 100 ° C., then washed with water, and this was repeated 12 times, and the presence or absence of cracks was visually evaluated.

[0020]

[Table 1]

[Brief description of drawings]

FIG. 1 is an overall view showing a model type of an automobile intake manifold used as an embodiment of the present invention.

FIG. 2 is a sectional view taken along the line AA of FIG. 1 showing a model type of an intake manifold for an automobile used as an embodiment of the present invention.

[Explanation of symbols]

 1 ... Collector part 2 ... Pipe part 3 ... Flange part (separately welded by injection molding) 4, 5 ... Cut part for uniform thickness evaluation

Claims (4)

[Claims] 1. A hollow molded article for an engine peripheral mechanism part, which comprises a hollow portion molded by blow molding using a polyarylene sulfide resin or a composition thereof. 2. The polyarylene sulfide resin composition comprises 5 parts by weight per 100 parts by weight of the polyarylene sulfide resin.
The hollow molded article for engine peripheral mechanism parts according to claim 1, which is a composition comprising from about 150 parts by weight of a fibrous filler. 3. A polyarylene sulfide resin is 310
Viscosity measured at a shear rate of 1200 sec ^-1 at 2000 to 20000
The hollow molded article for engine peripheral mechanism parts according to claim 1 or 2, which is a poise. 4. The hollow molded article according to claim 1, 2 or 3, wherein the engine peripheral mechanical component is an intake manifold.