JPH04288341A - Polyamide blow molding - Google Patents

Abstract

PURPOSE:To obtain a polyamide blow molding, especially a three-dimensional blow molding excellent in rigidity, heat resistance and impact resistance by mixing a specified polyamide with a specified resin and a fibrous reinforcement to form an intimate mixture improved in rigidity and heat distortion temperature characteristics. CONSTITUTION:A polyamide blow molding made from a polyamide composition comprising 100 pts.wt. intimate mixture comprising 50-90 wt. % hexamethylenedipamide component, 5-40wt.% hexamethyleneterephthalamide component and 5-30wt.% hexamethylene isophthalamide component and satisfying the relationships: melting temperature(Tm) >=225 deg.C and crystallization temperature (Tc) <=230 deg.C and 5-50wt.% ethylene ionomer resin and/or carboxy-modified elastomer (B) and having a melt viscosity satisfying formulas I and II and 1-100 pts.wt. fibrous reinforcement (C), wherein the mean particle diameter of the dispersed phase comprising component B dispersed in the polyamide matrix phase is 10mum or below.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention is a blown polyamide plastic with excellent rigidity, heat resistance, impact resistance, chemical resistance, road antifreeze resistance, low water absorption, dimensional stability, and heat distortion temperature characteristics. It relates to molded products, and more specifically to polyamides, ethylene ionomer resins and/or polyamides.
Alternatively, it is a polyamide blow-molded product with excellent rigidity, heat resistance, and impact resistance, which is made by blending a carboxy-modified elastomer and a fibrous reinforcing agent to form an intimate mixture with particularly improved rigidity and heat distortion temperature characteristics. , particularly regarding three-dimensional blow molded articles.

0002

[Prior Art] Polyamide resins are widely used as engineering plastics due to their excellent physical properties, but in order to make use of these excellent properties for use in a wider range of applications, polyamide resins are not necessarily satisfactory materials. do not have. For example, polyamides generally have the property that the change in melt viscosity with respect to shear rate is small, that is, the dependence of melt viscosity on shear rate is small.
Therefore, it is substantially difficult to obtain blow-molded products for large-capacity containers. In other words, when blow molding is performed using a normal screw-type blow molding machine, the raw material polymer is
In this case, it is desirable to have a low melt viscosity in terms of extruder power and productivity.On the other hand, when forming a parison from molten polymer, the polymer extruded from the die is plasticized at a high shear rate. - It is preferred to have a high melt viscosity at low shear rates in order to maintain sufficient melt morphology and obtain uniformity of dimensions and wall thickness of the molded article. Therefore, in order to obtain large-sized blow-molded products with good dimensional stability, it is first necessary to have a high melt viscosity.
Merely having a high melt viscosity of the raw material polymer is not sufficient; it is an extremely important requirement that the melt viscosity be highly dependent on shear rate. Furthermore, although polyamide is considered to be a relatively strong material, its toughness and impact resistance largely depend on temperature and moisture content. ,
When it is completely dry or at low temperatures, it becomes a quite brittle material. Therefore, in order to obtain polyamide blow-molded products that have truly high practical value as commercial products, one of the important problems that must be overcome is the improvement of impact resistance at low temperatures and low moisture absorption. Furthermore, as the weight of automobiles has been reduced in recent years, the use of plastic in engine compartments has led to the need for materials with higher rigidity, heat resistance, and high heat deformation temperature. A material with a deformation temperature is desired.

As described above, although polyamide has various excellent properties, it is currently not fully utilized, especially as blow molded products, due to the drawbacks mentioned above. Made of a polyamide material that has a high melt viscosity without sacrificing its useful properties, and also has a large shear rate dependence, it has excellent impact resistance at low temperatures and low moisture absorption, high rigidity, heat resistance, and heat distortion temperature characteristics. The reality is that the appearance of molded products is eagerly awaited in the industry.

The use of polyamides for blow molding applications is already widely known and we have developed a method for producing polyamides with melt viscosity properties suitable for the production of large extrusion and blow molded products. We have already made a few proposals regarding this. The outline is as follows. That is, a method in which a polyfunctional epoxy compound containing a vinyl epoxy group and a vinylene epoxy group is added to polyamide, mixed and heated and melted (Japanese Patent Publication No. 48-7509)
Alternatively, a method in which a diamine salt of trimesic acid is added during polymerization of a polyamide monomer such as lactam (JP-A-50-2790, JP-A-50-2791,
50-3193, 50-104297, etc.), a branched chain is introduced into a polyamide molecule. The branched polyamide produced by this method certainly has good viscosity stability, high melt viscosity, and a large change in melt viscosity with respect to shear rate, which are characteristics suitable for obtaining blow-molded products. There was no improvement in impact resistance, and a blow-molded product with excellent impact resistance, especially at low temperatures and low moisture absorption, could not be obtained. Next, we recognized that an effective way to solve this drawback, that is, to improve the impact strength of branched polyamides, is to blend ethylene-based ionomer resins, ethylene-vinyl acetate copolymers, etc. into branched polyamides. Showa 52-329
Furthermore, it has been discovered that nitrile rubber is extremely effective as an impact resistance improver for general polyamides (Japanese Patent Application Laid-Open No. 53-21252). Subsequently, we discovered that a mixture of polyamide, ethylene-based ionomer resin, and/or carboxy-modified nitrile rubber was a material with excellent melt viscosity characteristics and impact resistance, even compared to general polyamides (Tokuko Showa University). 55-416
Publication No. 59).

[0005]

[Problems to be Solved by the Invention] However, even when trying to obtain a three-dimensional blow-molded product with a relatively long parison length using such prior art materials, the appearance of the molded product is poor, and furthermore, the heat resistance is poor or the heat resistance is poor. Even if the material was good, it could not be said to be a sufficiently satisfactory material for producing three-dimensional blow molded products because the parison solidified quickly and a long parison could not be obtained.

The object of the present invention is to solve the above-mentioned conventional problems, and to create a product that has high rigidity, heat resistance, and high heat deformation temperature, has excellent impact resistance, and is also capable of forming three-dimensional blow molded products. The purpose of the present invention is to provide a polyamide blow-molded product using a polyamide-based material.

[0007]

[Means for Solving the Problems] That is, the present invention provides A(
a) Hexamethylene adipamide component (hereinafter abbreviated as 66) 50-90% by weight, (b) hexamethylene terephthalamide component (hereinafter abbreviated as 6T) 5-40% by weight, (c)
A polyamide consisting of 5 to 30% by weight of hexamethylene isophthalamide component (hereinafter abbreviated as 6I), which has a melting point (
Tm), 50 to 95% by weight of a crystalline polyamide whose crystallization temperature (Tc) satisfies Tm≧225°C and Tc≦230°C, and B: 5 to 50% by weight of ethylene ionomer resin and/or carboxy-modified elastomer % and 1 to 100 parts by weight of C fibrous reinforcing agent, the polyamide composition has a melt viscosity satisfying formula (I) and formula (II), and has a polyamide matrix phase. This is a polyamide blow molded article in which the average particle size of the dispersed phase consisting of an ethylene ionomer resin and/or a carboxy-modified elastomer dispersed therein is 10 microns or less.

[0008]lnμa10≧10.50−0.04
(T-Tm)...(I) μa
10/μa1000≧3.3
......(II) (in the above formula, Tm: melting point (°C) of polyamide
: Temperature (Tm+10℃) or higher (Tm+70℃) or lower (
℃) μa10: Temperature T (℃), shear rate 10 (sec
-1) Melt viscosity (poise) μa1000: temperature T (℃), shear rate 1000 (s
The melt viscosity (poise) in ec-1) is shown. ) In other words, the feature of the present invention is to optimize the melting point and crystallization temperature of the polyamide by specifying the composition of each polyamide component, and to create an intimate mixture of this polyamide with an ethylene ionomer resin and/or a carboxy-modified elastomer. We have specified the melt viscosity characteristics of materials made of fibrous reinforcement and the intimate mixing state of the dispersed phase in blow-molded products, and have found that the melt viscosity is highly dependent on the shear rate, and with good moldability, especially bone drying. We have made it possible to obtain blow molded products that have excellent impact resistance at high temperatures and low temperatures, and that have improved heat deformation temperature characteristics by adding a fibrous reinforcing agent, and have been found to be particularly effective for three-dimensional blow molding. It is in.

The melt viscosity of the composition obtained by adding a fibrous reinforcing agent to an intimate mixture of polyamide, ethylene ionomer resin and/or carboxy-modified elastomer, which is the raw material for obtaining the blow molded article of the present invention, is expressed by the above formula. It is necessary that (I) and (II) are satisfied.

Formula (I) is a formula that defines the viscosity above a certain level necessary for blow molding, and if the melt viscosity does not satisfy formula (I), the viscosity is low and blow molding cannot be performed satisfactorily. Generally, the melt viscosity of a polymer is expressed as a function of the measurement temperature and shear rate, but the measurement temperature is naturally determined by the melting point and softening point of the polymer, so when discussing a specific value of melt viscosity, the measurement temperature and The difference in melting point, i.e. (T-Tm
) is appropriate to display as a parameter. Melt viscosity is measured using an ordinary capillary viscometer, and ASTM-D-1
This is a value measured according to the method specified in 238. The measurement temperature is generally selected from a temperature range of 10 to 70° C. higher than the melting point of the polymer in relation to the molding temperature.

[0011] Equation (II) is a formula that expresses the magnitude of the shear rate dependence of melt viscosity, and is the ratio of the melt viscosity in the low shear rate region to the melt viscosity in the high shear rate region. It is a quantification of size. If the melt viscosity characteristic does not satisfy formula (II), the change in melt viscosity with respect to the shear rate is small and blow molding cannot be performed satisfactorily, which is not preferable. Shear rate expressed by formula (II) 10 sec-1 and 1000 sec
Ratio of melt viscosity at c-1 (μa10/μa100
Although the upper limit of 0) is not specified, a value of about 20 is a common sense upper limit in view of the performance of the molding machine.

The melt viscosity of the material is expressed by the above formulas (I) and (I
It is necessary to satisfy both conditions I), and even if only one of the conditions is satisfied, a good blow molded product cannot be obtained.

Polyamide A that can be used in the present invention
is a polyamide prepared within a composition range of (a) 50 to 90% by weight of the 66 component, (b) 5 to 40% by weight of the 6T component, and (c) 5 to 30% by weight of the 6I component. If the amount of component 66 is less than 50% by weight, the crystallinity of the obtained polyamide will be low and the balance of physical properties such as chemical resistance will be poor.
If it exceeds 90% by weight, the crystallization temperature will exceed 230°C, making it impossible to obtain a sufficiently long parison during blow molding, which is not preferred. Furthermore, if the 6T component is less than 5% by weight, the melting point of the obtained polyamide will be lower than 225°C, the heat resistance will decrease, and the balance of physical properties will deteriorate.
If it exceeds 40% by weight, although heat resistance is improved, the crystallization temperature exceeds 230°C, which is undesirable because it promotes solidification of the parison during blow molding. Furthermore, if the 6I component is less than 5% by weight, it will essentially become a 66/6T copolymer, and although the heat resistance will improve, the crystallization temperature will also exceed 230°C, which will accelerate the solidification of the parison during blow molding. If it exceeds this amount, the 6I component is amorphous and its melting point decreases, resulting in a decrease in crystallinity and heat resistance. That is, the polyamide of the present invention is designed to lower the crystallization temperature of nylon 66 by introducing the 6I component to improve blow moldability, and to compensate for the decrease in heat resistance due to the addition of the 6I component by adding the 6T component. It is based on ideology. A blow moldable polyamide with well-balanced physical properties cannot be obtained without such a design concept. Furthermore, Tm≧225℃, Tc≦2
66,6 to obtain a polyamide that satisfies the 30°C condition.
A polymerization test was carried out one by one within the above composition range of the T and 6I components, and the Tm, Tc, and crystallinity of the obtained polyamide were determined by measuring with a differential scanning calorimeter (DSC).

[0014] There are no particular restrictions on the polymerization method for polyamide, but usually melt polymerization, interfacial polymerization, solution polymerization, bulk polymerization,
Solid state polymerization and combinations thereof are utilized, with melt polymerization generally being the most suitable. The raw materials for each component are 6
6, 6T, and 6I may be charged into the polymerization kettle in the form of salts, or in the form of their respective monomers.

The degree of polymerization of the polyamide used here is not particularly limited, but it is usually determined from the relative viscosity (1 g of polymer is mixed with 98% concentrated hydrochloric acid 100%
ml and measured at 25°C. (same below) is 1.5 or more 5
Polyamides within the range below are desirable. Furthermore, in order to obtain stability in discharging the polymer from the polymerization kettle, it is possible to add monocarboxylic acid compounds, dicarboxylic acid compounds, monoamine compounds, diamine compounds, and derivatives thereof to the polymerization kettle together with monomers as polymerization stabilizers. Used as a useful method. Examples of these compounds include acetic acid, benzoic acid, stearic acid, sebacic acid, adipic acid,
Examples include dodecanedioic acid, undecanoic acid, terephthalic acid, isophthalic acid, suberic acid, cyclohexanedicarboxylic acid, stearylamine, ethylenediamine, decamethylenediamine, tetramethylenediamine, hexamethylenediamine, and the like.

[0016] In a preferred embodiment, the obtained polyamide is subjected to melt polymerization, if necessary, and then further subjected to solid phase polymerization in order to obtain a desired melt viscosity.

In the solid phase polymerization, polyamide may be used as it is, or a phosphorus compound or the like may be added to the polyamide as a polymerization accelerator. As the phosphorus compound, phosphoric acid, phosphorous acid, hypophosphorous acid, pyrophosphoric acid, polyphosphoric acid, and their alkaline earth metal salts can be effectively used. In particular, phosphoric acid is commonly used. The amount of the phosphorus compound added is not particularly limited, but is preferably 0.01 to 5.
%, more preferably 0.05 to 2%. One or more types of phosphorus compounds can also be used in combination. A commonly known method can be used for adding the phosphorus compound. For example, a method is preferably used in which a phosphorus compound or an aqueous solution of a phosphorus compound is added to polyamide resin pellets, powder, pieces, etc., and mixed using a Henschel mixer, tumbler, ribbon mixer, or the like. As a method of adjusting the melt viscosity, in addition to solid phase polymerization, it is also possible to melt-knead the polyamide resin to which the above-mentioned phosphorus compound is added. A known extruder can be used for melt-kneading.

The melting point of the polyamide used here is 22
It is necessary that the temperature is 5°C or higher. If the melting point is lower than 225°C, sufficient heat resistance cannot be obtained. Although there is no particular upper limit to the melting point, a value of 300° C. or lower is appropriate from the viewpoint of operability during polymerization and moldability during molding.

[0019] The crystallization temperature is 230°C or less,
This is necessary in order to obtain relatively long parisons. 230℃
If it is higher, the parison solidifies quickly and it becomes impossible to obtain the desired parison length. Although the lower limit of the crystallization temperature is not particularly limited, a temperature that allows crystallization at room temperature, ie, about 40° C., is generally appropriate. There are no particular limitations on crystallinity, and any polyamide within the composition range of the present invention can be used without any problem in crystallinity.

The ethylene ionomer resin used as component B of the present invention is an α-olefin containing ethylene and an α-olefin.
, the copolymer with β-unsaturated carboxylic acid has a valence of 1 to 3.
It is an ionic polymer to which metal ions have been added. Typical examples of α,β-unsaturated carboxylic acids include acrylic acid, methacrylic acid, and itaconic acid.
Typical examples of metal ions listed in No. 3 are Na+, K+, and C.
a++, Zn++, Al+++, and the like. These ethylene ionomer resins are generally “
Various grades commercially available under the trade name "Himilan" (formerly known as "Surlyn A") can be used.

The carboxy-modified elastomer used as component B of the present invention is ethylene, propylene, butene-1
, butadiene, isoprene, 1,3-pentadiene, pentene-1,4-methylpentene-1, isobutylene,
1,4-hexadiene, dicyclopentadiene, 2,5
- at least one selected from norbornene, 5-ethylidenenorbornene, 5-ethyl-2,5-norbornadiene, 5-(1'-propenyl)-2-norbornene, styrene, α-methylstyrene, vinyltoluene, etc. It is a modified polyolefin obtained by introducing an α,β-unsaturated carboxylic acid into a polyolefin obtained by radical polymerization of an olefin. Examples of α,β-unsaturated carboxylic acids used here include maleic acid, fumaric acid, itaconic acid, acrylic acid, crotonic acid, cis-4-cyclohexane-1,2-dicarboxylic acid and its anhydrides, derivatives and Examples include maleimide and its derivatives. There are no particular restrictions on the method of introducing the α,β-unsaturated carboxylic acid, such as mixing and copolymerizing the main component olefins and the α,β-unsaturated carboxylic acid, or using a radical initiator in the polyolefin. A method such as grafting and introducing an α,β-unsaturated carboxylic acid can be used. The amount of α,β-unsaturated carboxylic acid introduced is 0.001 to 40 mol%, preferably 0.01 to 40 mol%, based on the polyolefin.
It is suitably within the range of 35 mol%.

Specific examples of carboxy-modified elastomers particularly useful in the present invention include ethylene/ethyl acrylate.
g-Maleic anhydride copolymer (“g” represents graft, same hereinafter), ethylene/methyl methacrylate-g-maleic anhydride copolymer, ethylene/ethyl acrylate-
g-maleimide copolymer, ethylene/ethyl acrylate-g-N-phenylmaleimide copolymer and saponified products of these copolymers, ethylene/propylene-g-maleic anhydride copolymer, ethylene/butene-1- g-maleic anhydride copolymer, ethylene/propylene/1,4-hexadiene-g-maleic anhydride copolymer, ethylene/
Propylene/dicyclopentadiene-g-maleic anhydride copolymer, ethylene/propylene/2,5-norbornadiene-g-maleic anhydride copolymer, ethylene/propylene-g-N-phenylmaleimide copolymer, ethylene/ Butene-1-g-N-phenylmaleimide copolymer, styrene/maleic anhydride copolymer, styrene/butadiene/styrene-g-maleic anhydride block copolymer, styrene/butadiene/styrene block copolymer with hydrogen Styrene/ethylene/butylene/styrene obtained by grafting maleic anhydride after addition
-maleic anhydride block copolymer, styrene/isoprene-g-maleic anhydride block copolymer, etc., and each of these can be used alone or in the form of a mixture.

The intimate mixture used in the present invention is polyamide A.
5 to 50% by weight, particularly preferably 10 to 40% by weight of ethylene-based ionomer resin and/or carboxy-modified elastomer B are intimately mixed. If the amount of the ethylene-based ionomer resin and/or the carboxy-modified elastomer B is less than 5% by weight, not only will the effect of increasing the shear rate dependence of the melt viscosity of the mixture decrease noticeably, but also the blowing with excellent impact resistance will occur. It becomes impossible to obtain molded products. On the other hand, if the amount of ethylene-based ionomer resin and/or carboxy-modified elastomer B exceeds 50% by weight, not only will the heat resistance decrease, but the characteristics of polyamide will not be exhibited, and the original purpose of a polyamide-based plastic blow molded product will be This is not desirable because it is different from the

It is useful to add the fibrous reinforcing agent C used in the present invention in order to obtain the rigidity and high heat distortion temperature of the polyamide composition that is the raw material. Examples of fibrous reinforcing agents include aramid fibers, polyamide fibers, glass fibers,
Examples include carbon fibers, alumina fibers, silicon carbide fibers, boron fibers, zirconia fibers, potassium titanate whiskers, and glass fibers and carbon fibers are particularly preferred. These fibrous reinforcing agents can be used untreated or with thermally stable silane coupling agents such as triethoxy-γ-aminopropylsilane, N-β(aminoethyl)-γ-aminopropyltrimethoxysilane, etc. The fibrous reinforcing agent may be surface-treated with silane, vinyltriethoxysilane, γ-glycidoxypropyltrimethoxysilane, etc., and it is also possible to use two or more of these fibrous reinforcing agents. In addition to fibrous reinforcing agents, so-called inorganic fillers such as talc, kaolin, gypsum, mica,
Quartz, calcium carbonate, magnesium hydroxide, calcium phosphate, titanium phosphate, sericite, anhydrous mica, wollastonite, diatomaceous earth, clay, white carbon, carbon black, zinc powder, etc. can be added.

The fibrous reinforcing agent C of the present invention is used in an amount of 1 to 100 parts by weight, particularly preferably 5 to 90 parts by weight, per 100 parts by weight of an intimate mixture of polyamide A and ethylene ionomer resin and/or carboxy-modified elastomer B. It is desirable to mix 1 part. If the blending amount of the reinforcing agent exceeds 100 parts by weight, it is not preferable because the properties of the polyamide will not be exhibited and the original purpose will be different. On the other hand, fibrous reinforcement C
If the amount is less than 1 part by weight, the effect as a reinforcing agent will not be exhibited and the purpose of obtaining a reinforced polyamide composition will not be achieved.

The method of mixing polyamide A with ethylene ionomer resin and/or carboxy-modified elastomer B and fibrous reinforcing agent C is not particularly limited, and any commonly known method can be used. After uniformly mixing polyamide A, ethylene-based ionomer resin and/or carboxy-modified elastomer B pellets, powder, and pieces with fibrous reinforcing agent C using a high-speed stirrer, the mixture is melted using an extruder with sufficient kneading capacity. Alternatively, polyamide A and ethylene-based ionomer resin and/or carboxy-modified elastomer B are melt-kneaded using an extruder to form pellets, and then a fibrous reinforcing agent is added to the dried pellets and molded using a blow molding machine. The method of doing so is suitable. It is also possible to use a method in which the homogeneously mixed mixture is not kneaded in advance in an extruder, but is directly kneaded in a molding machine during blow molding, and then molded. There are no restrictions on the blow molding method, and conventionally known methods can be used. That is, in general, after forming a parison using an ordinary blow molding machine, blow molding may be carried out at an appropriate temperature.

In order for the blow-molded article of the present invention obtained as described above to have excellent rigidity, heat deformation temperature and impact strength, both of the polymers as constituent components must be intimately mixed with each other, and The fibrous reinforcement must be uniformly distributed. One method for evaluating the mixed state of both polymers is to use the particle size of the dispersed phase as an evaluation measure.
The blow molded article of the present invention is in a state in which the dispersed average particle diameter of the ethylene ionomer resin and/or carboxy-modified elastomer portion as a dispersed phase dispersed in the polyamide matrix phase is 10 microns or less, more preferably 5 microns or less. It is necessary to improve the impact resistance strength, especially in order to obtain a molded product with excellent impact resistance at low temperature and low moisture absorption. If the average particle size of the dispersed phase exceeds 10 microns, the effect of improving impact strength will be reduced, making it impossible to obtain a molded article with excellent impact resistance, especially at low temperatures and low moisture absorption. However, since the ethylene-based ionomer resin and/or carboxy-modified elastomer B used in the present invention have good compatibility with polyamide A, it is relatively easy to achieve the intimate mixing state specified here. Preferably, the composition is melt-kneaded once in an extruder before blow molding. Also, during blow molding, it is appropriate to use a blow molding machine equipped with a screw having a high kneading capacity. In order to examine the mixing state of the blow molded product, that is, the particle size of the dispersed phase in the matrix phase, it is sufficient to cut out a part of the molded product and directly measure the particle size using a microscope or the like. The dispersibility of the fibrous reinforcing agent can also be evaluated at the same time.

The blow molded product of the present invention also has moldability,
It is also possible to add and introduce other components, such as pigments, weathering agents, crystallization promoters, heat resistant agents, flame retardants, lubricants, mold release agents, etc., as long as the physical properties are not impaired.

The present invention will be explained in more detail with reference to Examples below. The impact resistance of the blow molded products listed in Examples and Comparative Examples was evaluated by the following method. That is, a reagent container with an internal volume of 500 ml obtained by blow molding was filled with water at 0°C, the mouth was tightly stoppered, and the container was placed on a horizontal concrete floor from a height of 2.5 m with the bottom facing downward. The container was dropped repeatedly to determine the number of drops until the container broke. This test was conducted on five containers made under certain conditions. The present invention is not limited to the following examples unless it exceeds the gist thereof.

Reference Example 1 (Production of polyamide of the present invention) 66 components (raw materials: hexamethylene diamine/adipic acid), 6T components (raw materials: hexamethylene diamine/terephthalic acid), 6I components (raw materials: hexamethylene diamine/isophthalic acid) Weigh out each monomer (acid) so that it has the composition shown in Table 1, add it to a polymerization pot, and melt-polymerize it to form a polymer.
And so. After the polymerization was completed, the mixture was discharged from the bottom of the polymerization vessel, drawn into a strand, and pelletized using a pelletizer. After drying this pellet in vacuum, various properties were measured and the results shown in Table 1 were obtained.

[0031]

[Table 1]

Example 1 Polyamide species N-1 of Reference Example 1 was solid-phase polymerized at 280°C.
, the melt viscosity at a shear rate of 10 sec-1 is μa10
=9000 poise polyamide was obtained. For this polyamide, styrene/ethylene/butylene/styrene-g-
20% by weight of maleic anhydride block copolymer (trade name "Tuftec" M1913 (manufactured by Asahi Kasei Corporation); hereinafter abbreviated as modified SEBS) was added and mixed, and 20 parts by weight of glass fiber was added to 100 parts by weight of this mixture. and further mixed. This mixture was melt-kneaded in an extruder with a diameter of 30 mm set at 280°C, and then pelletized. After drying the pellet in vacuum, the melt viscosity (μa10 and μa1000, respectively) at a temperature of 280°C and a shear rate of 10 sec-1 and 1000 sec-1 was measured using a melt indexer manufactured according to ASTM-D-1238. did. The result is μa10=110000 poise, μ
a1000=9000 poise, and these values are expressed by the formula (
It satisfied I) and (II).

Next, the pellets obtained here have a diameter of 40 mmφ.
of outer diameter 2 at 280°C using a blow molding machine with an extruder of
When we formed a parison with a thickness of 0 mm and a wall thickness of 2 mm, and observed the condition of the parison when molding a 500 ml reagent bottle, we found that there was no sagging of the parison at all, indicating that blow molding could be carried out very well and that the wall thickness had a good appearance. It was possible to obtain a uniform molded product.

[0034] A part of this molded product was cut out, and the sample was cut into an extremely thin piece using an ultramicrotome, and the particle size of the modified SEBS phase as a dispersed phase was observed using an electron microscope, and it was found to be 1.0 microns on average. It was confirmed that modified SEBS was finely dispersed in the polyamide matrix. It was also observed that the glass fibers were also uniformly dispersed.

[0035] Furthermore, when the impact resistance of the blow molded product was investigated by a drop test, the number of tests until the molded product broke was 10.
It was found that it had excellent practical impact resistance.

Further, in order to evaluate the thermal deformation characteristics, a part of the molded product was cut out and subjected to a load of 18 cm according to ASTM-D-648.
．． The heat distortion temperature was measured at 6kg/cm2.2
The temperature was as high as 35°C.

Using the same blow molding machine, the same material was molded with an outer diameter of 20 mm.
A parison with a thickness of 2 mm and a wall thickness of 2 mm was formed, and molded into a complex-shaped pipe with an outer diameter of 5 mm and a length of 700 mm using a three-dimensional blow molding mold. There was no sagging of the parison, and the shape could be molded to the mold dimensions with a good appearance.

Example 2 The procedure was carried out in exactly the same manner as in Example 1, except that 20% by weight of "Himilan" 1706 (ionomer resin manufactured by Du Pont, USA) was added and mixed in place of the modified SEBS used in Example 1. A composition of polyamide, "Himilan" 1706 and glass fiber was obtained. The shear rate of this composition at a temperature of 280°C is 10 sec-1 and 1000 sec-1
The melt viscosity is μa10=95000 poise, μa
1000=9000 poise, and in this case as well, the melt viscosity value satisfied formulas (I) and (II).

Next, using the same equipment as in Example 1, a 500 ml container was blow-molded under the same conditions, and the shape retention of the parison was extremely good, making it easy to produce a blow-molded product with a uniform wall thickness and good appearance. I was able to get it. In addition, the mixed state and impact resistance of this molded article were evaluated in the same manner as in Example 1. In this case as well, the average particle size of the "HIMILAN" 1706 phase dispersed in the polyamide matrix was 1.
．． 1 micron, and even for drop tests, the number of tests is 1
It showed an excellent value of 0 times or more.

The heat distortion temperature was also measured in the same manner as in Example 1 and showed a high value of 233°C.

[0041] The same material was molded using the same blow molding machine with an outer diameter of 20 mm.
A parison with a thickness of 2 mm and a wall thickness of 2 mm was formed, and was molded into a complex-shaped pipe with an outer diameter of 50 mm and a length of 700 mm using a three-dimensional blow mold. There was no sagging of the parison, and the shape could be molded to the mold dimensions with a good appearance.

Comparative Example 1 Polyamide and "
A composition was obtained with Himilan" 1706. The shear rate of this composition at a temperature of 280°C was 10 sec-1 and 10 sec-1.
The melt viscosity at 00 sec-1 is μa10 = 6500
0 poise, μa1000=7000 poise, and in this case as well, the melt viscosity value satisfied formulas (I) and (II). “Dispersed in a polyamide matrix”
The average particle size of the Himilan" 1706 phase was 1.1 microns.

This material was molded into a 500 ml container using the same blow molding machine as in Example 1. Although there were no problems with moldability, the heat distortion temperature was measured at 70°C, which was much lower than that of the glass fiber reinforced product.

Example 3 Polyamide species N-2 of Reference Example 1 was solid-phase polymerized at 270°C.
A polyamide having a melt viscosity of μa10=13000 poise at a shear rate of 10 sec-1 was obtained. For this polyamide, ethylene/propylene-g-maleic anhydride copolymer (manufactured by Exxon, trade name "Excera")
20% by weight of VA1803 (hereinafter abbreviated as modified EPR)
A composition of polyamide, modified EPR, and fibrous reinforcing agent was obtained in the same manner as in Example 1, except that 20 parts by weight of glass fibers as a fibrous reinforcing agent were added to 100 parts by weight of the added mixture. The melt viscosity of this composition at a temperature of 270°C and a shear rate of 10 sec-1 and 1000 sec-1 is μa10 = 150000 poise, μa10
00=10500 poise, and in this case as well, the melt viscosity value satisfied formulas (I) and (II). Subsequently, using the same apparatus as in Example 1, 500 ml was added under the same conditions.
When the container was blow-molded, the shape retention of the parison was extremely good, and a blow-molded product with uniform wall thickness could be easily obtained. Furthermore, when the mixed state and impact resistance of this molded article were evaluated in the same manner as in Example 1, the average particle size of the modified EPR phase dispersed in the polyamide matrix was 1.2 microns. The dispersibility of glass fibers was also good. It also showed excellent results in the drop test, with more than 10 tests. Further, the thermal deformation characteristics were evaluated in the same manner as in Example 1, and it was found to have a high thermal deformation temperature of 230°C. The same material was molded using the same blow molding machine with an outer diameter of 2 mm.
A parison with a diameter of 0 mm and a wall thickness of 2 mm was formed, and molded into a complex-shaped pipe with an outer diameter of 50 mm and a length of 700 mm using a three-dimensional blow mold. There was no sagging of the parison, and the shape could be molded to the mold dimensions with a good appearance.

[0045]

[Effects of the Invention] By using the polyamide composition of the present invention, it is now possible to inexpensively produce blow-molded products with desirable properties that could not be achieved with existing single materials, and the excellent features of polyamide can be produced. Taking advantage of this, it has become possible to use it in various blow molded products. In particular, the polyamide composition of the present invention allows blow-molded products with high impact strength, high rigidity, and high heat deformation temperature characteristics to be obtained, and in particular, it has become possible to mold three-dimensional blow-molded products with complex shapes, which is a feature of recent automobiles. This is of great significance as it is consistent with the movement towards weight reduction.

Claims (1)

[Claims] Claim 1: A(a) hexamethylene adipamide component
A polyamide consisting of 50 to 90% by weight, (b) hexamethylene terephthalamide component 5 to 40% by weight, and (c) hexamethylene isophthalamide component 5 to 30% by weight, melting point (Tm), crystallization temperature (Tc) is 50 to 95% by weight of crystalline polyamide satisfying Tm≧225°C Tc≦230°C, and B
Intimate mixture with 5-50% by weight of ethylene-based ionomer resin and/or carboxy-modified elastomer
100 parts by weight, 1 to 100 parts by weight of C fibrous reinforcing agent, a polyamide composition whose melt viscosity satisfies formulas (I) and (II), and ethylene dispersed in a polyamide matrix phase. A polyamide blow-molded article in which the average particle size of a dispersed phase consisting of an ionomer resin and/or a carboxy-modified elastomer is 10 microns or less. ln μa10≧10.50−0.04(
T-Tm)・・・・・・(I)μa
10/μa1000≧3.3
......(II) (In the above formula, Tm: Melting point (°C) of polyamide
: Temperature (Tm+10℃) or higher (Tm+70℃) or lower (
℃) μa10: Temperature T (℃), shear rate 10 (sec
-1) Melt viscosity (poise) μa1000: temperature T (℃), shear rate 1000 (s
The melt viscosity (poise) in ec-1) is shown. )