JPH1148317A - Hollow molding made of synthetic resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a molding, excellent in mechanical characteristics as well as resistance to thermal deformation and suitable for the use of re-cycling by a method wherein the specified ratio of liquid crystal resin and thermosetting resin are contained in a synthetic resin while the synthetic resin is molded through blow molding, in which a blow ratio is specified. SOLUTION: The mixing ratio of a thermosetting resin and a liquid crystal resin is 1-40 wt.% of the liquid crystal resin to 69-99 wt.% of the thermosetting resin. The hollow molding of the synthetic resin is molded through blow molding with a blow ratio within the range of 1.05-5. ABS resin, an ethylene acetate vinyl copolymer, a fluorine resin and the like are preferable for the thermosetting resin employed for the blow molding. The liquid crystal resin is not limited especially whenever the liquid crystal resin is provided with a liquid crystal transition temperature higher than the melting point of thermosetting resin or the matrix of the resin, however, the thermosetting liquid crystal polyester, such as whole aromatic series polyester resin, semi-aromatic series polyester resin, non-aromatic series polyester resin and the like, are employed as the liquid crystal resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a synthetic resin hollow molded article obtained by blow molding, and more particularly, to a hollow molded article made of synthetic resin.
The present invention relates to a synthetic resin hollow molded article excellent in heat deformation resistance, mechanical strength, recyclability and cost performance.

[0002]

2. Description of the Related Art Conventionally, thermoplastic resin hollow molded articles have been widely used for containers such as bottles and tanks, heat insulating materials or electric insulating materials. Also, metal parts have been used as automotive parts such as bumper beams for automobiles. In recent years, plastic parts have been used in order to reduce the weight, improve rust resistance and improve shapeability of these automotive parts. Automotive parts are being used.

[0003] As a plastic bumper beam,
For example, a stampable sheet formed by press molding or an engineering plastic blow molded is known. However, these plastic bumper beams have a high specific gravity, and there is a problem that a sufficient weight reduction effect cannot be obtained. In addition, these molded products do not have sufficient chemical resistance, and when recycled, the moldability of the resin is significantly reduced,
It was difficult to reuse industrially.

On the other hand, JP-A-8-208912 discloses a resin composition for blow molding comprising 1 to 30% by weight of talc with respect to 70 to 99% by weight of a polypropylene resin mixture. In the resin composition for blow molding described in this prior art, the mechanical strength is improved by including talc as a filler.

[0005] However, when the above resin composition for blow molding is blow molded to obtain a hollow molded product,
Although moldability such as mechanical strength, dimensional accuracy, and drawdown resistance is improved compared to polypropylene molded products, the use of talc as a filler reduces the reinforcing effect and gas barrier properties of the resulting hollow molded product. There was a problem that it was not enough.

Japanese Unexamined Patent Publication (Kokai) No. 62-116666 discloses a polymer composite which is lighter than fiber reinforced plastics and which can increase mechanical strength. A method for producing a self-reinforced polymer composite is disclosed in which a base polymer having the following formula is combined with a melt-processable liquid crystal resin incompatible with the base polymer.

[0007] That is, a reinforced plastics in which a liquid crystal resin is combined with a thermoplastic resin to increase the mechanical strength by the liquid crystal resin, and a method of manufacturing the same are disclosed. In this prior art, the resulting polymer composite is
It has been shown that pellets are formed according to a molding method such as extrusion molding or injection molding so as to be formed into a tape, film or fiber, but there is no mention of application to a blow molded product or a blow molding method. .

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a hollow molded article made of synthetic resin obtained by blow molding suitable for obtaining a hollow molded article, which has excellent mechanical properties and heat-resistant deformation properties, and is recyclable. An object of the present invention is to provide a synthetic resin hollow molded body suitable for use.

[0009]

The invention according to claim 1 is a synthetic resin hollow molded article obtained by blow molding, wherein 1 to 40% by weight of a liquid crystal resin and 60 to 60% of a thermoplastic resin are used.
99% by weight, and is blow-molded at a blow ratio of 1.05 to 5.

[0010] In the invention according to claim 2, the liquid crystal resin is dispersed in a fibril form in a thermoplastic resin. In the invention according to claim 3, the thermoplastic resin contains a non-crosslinked polyolefin resin and a crosslinkable polyolefin resin. Hereinafter, details of the present invention will be described.

(Thermoplastic Resin) The thermoplastic resin used in the present invention is not particularly limited. For example, ABS resin, ethylene-vinyl acetate copolymer, fluororesin, acetal resin, amide resin, Examples include imide resin, amide imide resin, acrylic resin, vinyl chloride resin, olefin resin, polyester, polycarbonate, polyacrylate, polyphenylene oxide, polystyrene, and thermoplastic polyurethane. Further, as the thermoplastic resin, modified products of these resins, a blend material (alloy material) obtained by blending two or more of these resins, or the like may be used. Above all, it is preferable to use a polyolefin resin, polystyrene, an olefin-based or styrene-based copolymer resin as the thermoplastic resin because the material and the cost of the hollow molded article are balanced.

(Liquid Crystal Resin) The liquid crystal resin is not particularly limited as long as it has a liquid crystal transition temperature higher than the melting point of the thermoplastic resin serving as a matrix. It is preferable to use a thermoplastic liquid crystal polyester such as an aromatic polyester resin and a non-aromatic polyester resin, or a thermoplastic liquid crystal polyester amide because of excellent fibrillation characteristics and moldability. More specifically, commercial products such as Vectra (manufactured by Polyplastics), Econol (manufactured by Sumitomo Chemical), Zyder (manufactured by Amoco), trade name: Rodrun (manufactured by Unitika), etc. A wholly aromatic polyester resin or a semi-aromatic polyester resin can be used.

(Compatibilizer) In the present invention, if necessary, the mixed resin composition of the liquid crystal resin and the thermoplastic resin may be solubilized before or during molding in order to improve the mutual compatibility. An agent may be added. As a compatibilizer,
For example, when the thermoplastic resin is an olefin resin,
Those obtained by copolymerizing an olefin component with a styrene component or an aromatic polyester component; olefin resins having a maleic acid component or an acrylic acid component; and olefin resin copolymers having a glycidyl methacrylate component. The number of parts of the compatibilizer to be added is usually 0.01 to 20 parts by weight, preferably 0.1 to 3 parts by weight based on 100 parts by weight of the total of the thermoplastic resin and the liquid crystal resin. When the amount is less than 0.01 part by weight, the effect of improving the compatibility by adding the compatibilizing agent may not be sufficient. May deteriorate in mechanical properties.

(Mixing ratio of thermoplastic resin and liquid crystal resin)
The mixing ratio of the liquid crystal resin to the thermoplastic resin is 1 to 40% by weight, preferably 1 to 30% by weight, more preferably 3 to 2% by weight, based on 60 to 99% by weight of the thermoplastic resin.
0 resin%. When the mixing ratio of the liquid crystal resin is less than 1% by weight, the amount of the liquid crystal resin becomes too small, and the heat-resistant deformation property and mechanical strength of the obtained hollow molded article become insufficient. On the other hand, when the mixing ratio of the liquid crystal resin exceeds 40% by weight, surface appearance defects such as rough skin and local thin portions occur, and a uniform hollow molded body having good surface properties cannot be obtained.

(Blow Ratio) The blow molding ratio of the synthetic resin hollow molded article according to the present invention is 1.05 to 5, preferably 1.2 to 5.
3 is blow molded. This blow ratio is appropriately selected depending on the resin composition and the properties and applications required for the product. If the blow ratio is less than 1.05, the adhesion to the mold during blow molding becomes insufficient, and if the blow ratio exceeds 5, The shape and thickness distribution of the molded product become uneven, and a uniform hollow molded product cannot be obtained.

In the present specification, the blow ratio is
The expansion ratio of the parison is shown, and the diameter of the parison before expansion is D0, the thickness of the resin before expansion is t0, the diameter of the parison after expansion is D1, or the thickness of the molded body after expansion is D0. When t1, the ratio D1 / D of the diameter of the parison
0 or a value represented by the thickness ratio t0 / t1.

(Production Method) In producing the synthetic resin hollow molded article according to the present invention, a conventionally known blow molding method can be used. For example, there is a method of extrusion blow molding or injection blow molding of a mixed resin containing a liquid crystal resin and a thermoplastic resin.

In this case, the mixed resin contains the above-mentioned thermoplastic resin and liquid crystal resin, and can be obtained by a conventionally known mixing method. For example, a method of dry-mixing both with a mixer such as a tumbler, a method of melt-mixing with an extruder, and the like can be adopted. In particular, a mixed material obtained by previously melting and mixing a thermoplastic resin and a liquid crystal resin with an extruder, extruding, and cutting into a pellet shape is preferably used. The specific example of the manufacturing method is as follows.

The raw materials for forming the liquid crystal resin and the thermoplastic resin are 2
The mixture is put into a shaft kneading extruder, extruded into a strand or a sheet at least at the melting point or the melting temperature of the thermoplastic resin or higher, cooled, and cut to obtain mixed pellets. In this case, a powdery or pellet-like material can be suitably used as the forming raw material.

The above-mentioned mixed pellets are supplied to a blow molding machine having a crosshead die attached to the tip of a single-screw extruder, and a cylindrical parison is extruded downward at a temperature at least equal to or higher than the melting point or melting temperature of the thermoplastic resin. With the resin extruded to a predetermined length, mold clamping is performed from the left and right with a mold corresponding to the product shape. Next, a blow pin is driven in, compressed air is sent from the pin, and then cooled to obtain a blow molded product.

(Invention of Claim 2) In the invention of Claim 2, in the synthetic resin hollow molded article, a liquid crystal resin is dispersed in a fibril form in a thermoplastic resin matrix. The fibril shape indicates a shape in which the dispersed liquid crystal resin has an aspect ratio (length / diameter) of 1 or more, and the aspect ratio is desirably 10 or more.

Further, the fibril diameter is preferably 100 μm or less, more preferably 10 μm or less. If the aspect ratio is less than 1, the effect of increasing the mechanical strength may not be sufficiently obtained because the liquid crystal resin does not have a fibril shape. The fibril diameter is 100μ
If m exceeds m, the resulting material may be brittle and the dispersion may be non-uniform.

In order to disperse the liquid crystal resin in a fibril form in the composition, for example, a composition comprising a thermoplastic resin and a liquid crystal resin is heated to a temperature not lower than the transition point of the liquid crystal resin, and a shear stress or an extension stress is applied. And the like can be achieved by applying an external stress such as

More specifically, the method of forming the liquid crystal resin into fibrils is, for example, a method of melting and mixing a thermoplastic resin and a liquid crystal resin to obtain the mixed resin.
A method in which a shearing force is applied in an extruder or a mold may be used. When the liquid crystal resin becomes fibrous in the thermoplastic resin, the apparent shear rate acting on the resin is 1 × 10 ² to 10
⁵ sec ^-1 , more preferably 3 × 10 ² to 10 ⁴ sec
It should be ^-1 . By being extruded at a shear rate in the above range, the liquid crystal resin in the resin blend is easily fibrillated, and fibrils having a fibril diameter of 10 μm or less and a fibril length of 0.1 mm or more can be obtained.

It is also possible to fibrillate a parison made of a resin mixture at the time of blow molding by blow molding at a temperature higher than the liquid crystal transition point. The degree of fibrillation of the liquid crystal resin contained in the finally obtained synthetic resin molded product can be visually confirmed by microscopic observation or soft X-ray observation. In the present invention, it is desirable that at least 10% or more of the liquid crystal resin is in the form of fibrils.

(Invention of Claim 3) In the invention of Claim 3, the thermoplastic resin contains a non-crosslinked polyolefin resin and a crosslinkable polyolefin resin. Here, as the polyolefin resin that can be used, homopolymers such as low-density polyethylene, high-density polyethylene, linear low-density polyethylene, homopolypropylene, random polypropylene, and block polypropylene, and ethylene-vinyl acetate copolymer (EVA) ), And copolymers such as ethylene-acrylic acid copolymer (EEA). As the non-crosslinked polyolefin resin,
These polyolefin resins may be used alone or in combination of two or more.

Examples of the crosslinkable polyolefin resin include a polyolefin resin in which a peroxide or a reactive monomer is added to the above-mentioned various polyolefin resins, a silane crosslinkable polyolefin resin, a polyethylene resin crosslinked by an electron beam, and the like. Can be. The method for crosslinking these crosslinkable polyolefin resins is not particularly limited, and examples thereof include a method using a peroxide, a method by water crosslinking, and a method of irradiating with ionizing radiation.

In the crosslinking method using a peroxide, various radical generators such as benzoyl peroxide can be used alone or in combination with a vinyl resin-containing monomer (for example, styrene monomer) or a polymer (for example, butadiene polymer). And crosslinking at a temperature higher than the decomposition temperature of the peroxide. Therefore, in the present invention, if molding is performed using an olefin resin in which a peroxide or the like is previously blended, crosslinking can be performed by a heat history during molding or a heat treatment after molding.

The cross-linking method by water cross-linking is a method of using a silane cross-linkable polyolefin resin and cross-linking the mixed resin pellets or the like or the molded article formed as described above by contacting with water or steam. The temperature and the time at the time of the contact can be appropriately adjusted.

The silane crosslinkable polyolefin resin refers to a thermoplastic resin such as polyethylene or polypropylene obtained by graft-modifying a silane compound having an unsaturated group, or a copolymer thereof. Examples of the silane compound having an unsaturated group include, for example, vinyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, and the like.

The silane crosslinkable polyolefin resin is
For example, it has an alkoxy group such as a methoxy group, and the alkoxy group comes into contact with water and hydrolyzes to a silanol group. The hydroxyl group of the silanol group reacts with the hydroxyl group of another molecule to form a Si—O—Si bond, whereby a crosslinked thermoplastic resin is obtained. At this time, a silanol condensation catalyst may be used in combination to promote crosslinking. Examples of such a silanol condensation catalyst include dibutyltin diphthalate, cobalt octoate, zinc stearate and the like. The addition amount of the silanol condensation catalyst is based on the silane crosslinkable polyolefin resin.
0.001 to 10% by weight is preferred.

The crosslinking method using ionizing radiation is a method in which a molded article is irradiated with an electron beam, γ-ray, or the like to cause crosslinking. In this case, the above-mentioned peroxides and monomers having a vinyl group may be combined.

Other methods include a method of crosslinking using ultraviolet light and a method of crosslinking using visible light. In this method, an initiator which decomposes by ultraviolet light or visible light to generate radicals is used as a thermoplastic. Add to resin.

The above-mentioned various crosslinking methods may be performed alone, or a plurality of crosslinking treatment methods may be used in combination. Also,
The crosslinking treatment is preferably performed before blow molding. That is, by blow molding the crosslinkable polyolefin after crosslinking, the melt elongation of the parison is remarkably improved, the blowdown resistance is improved, and a molded article having a uniform thickness can be easily obtained.

The mixing ratio of the non-crosslinked polyolefin resin and the crosslinkable polyolefin resin is not particularly limited, and the mixing method may be a melt kneading method using a twin screw extruder. .

(Other Additives) In the present invention, known fillers, antioxidants, pigments, flame retardants and nucleating agents may be added to the molded article, if necessary, within a range not to impair the object of the present invention. An agent may be added. Moreover, the synthetic resin hollow molded article according to the present invention may have a multilayer structure of two or more layers, depending on the application and shape.

(Use) The present invention provides a synthetic resin hollow molded article, but the use of the synthetic resin hollow molded article is not particularly limited. For example, hollow containers such as tanks and bottles, It can be used for molded articles having double walls, automobile parts such as bumpers and spoilers, and building materials such as door materials.

(Function) The synthetic resin hollow molded article according to the first aspect of the present invention contains 1 to 40% by weight of a liquid crystal resin and 60 to 99% by weight of a thermoplastic resin, and has a blow ratio of 1.0 to 1.0.
Since the blow molding is performed so that the ratio is 5 to 5, the liquid crystal resin is dispersed in the thermoplastic resin matrix, and the heat deformation resistance and the chemical resistance are improved. Moreover, since the synthetic resin hollow molded article of the present invention is made of a liquid crystal resin and a thermoplastic resin, remelting is easy.

According to the second aspect of the present invention, since the liquid crystal resin is dispersed in the form of fibrils, the reinforcing effect of the liquid crystal resin is enhanced, and the rigidity and strength of the synthetic resin hollow molded article are further enhanced. .

According to the third aspect of the present invention, since the thermoplastic resin contains a non-crosslinked polyolefin resin and a crosslinkable polyolefin resin, the thermoplastic resin has excellent elongation characteristics upon melting and is suitable for blow molding.

[0041]

The present invention will be clarified by the following non-limiting examples. In addition, the liquid crystal phase transition temperature in the following is a value measured by DSC (differential calorimeter).

Example 1 As a liquid crystal resin, VECTRA A950 manufactured by Polyplastics (liquid crystal transition temperature: 280 ° C.)
14% by weight and a homopolypropylene as a thermoplastic resin (melting point 165 ° C., melt index MI = 0.1)
86% by weight when the cylinder temperature was set to 290 ° C.
The mixture was melt-kneaded with a 0 mm extruder, extruded into strands, and then cut to obtain pellets. At this time, the form of the liquid crystal resin contained in the pellet was changed by an electron microscope (magnification: 50
(0x), most of the liquid crystal resin was in the form of fibrils.

The obtained pellets were supplied to a 50 mm single-screw extrusion blow molding machine (JEB-7, manufactured by Nippon Steel Works, Ltd.).
At a speed of 0 kg / hour, die diameter = 75 mm, core diameter = 7
Using a mold having a die gap of 0 mm and a die gap of 2.5 mm, an extrusion temperature of 210 ° C., and a blow ratio =
A hollow molded body having an outer diameter of 125 mm and a height of 260 mm was obtained by molding at 1.67. The obtained hollow molded body was dissolved in hot xylene, and the form of the remaining liquid crystal resin was observed with an optical microscope. As a result, most of the liquid crystal resin remained in the form of fibrils.

Example 2 As a liquid crystal resin, Rodrun LC3000 (transition temperature: 185 ° C.) manufactured by Unitika Ltd.
% By weight and 86% by weight of a homopolypropylene (melting point: 165 ° C., MI = 0.1) as a thermoplastic resin were melt-kneaded by a 30 mm extruder having a cylinder temperature set to 200 ° C., and extruded into strands. Thereafter, cutting was performed to obtain pellets.

In the same manner as in Example 1, the obtained pellets were supplied to a 50 mm single screw extrusion blow molding machine, and 10 kg /
Extrusion blow molding was performed at a rate of time with an extrusion temperature of 210 ° C. The obtained hollow molded body was dissolved in hot xylene, and the form of the remaining liquid crystal resin was observed with an optical microscope.
Some were present in fibril form.

Example 3 As a liquid crystal resin, VECTRA A950 (transition temperature: 280 ° C.) 14 manufactured by Polyplastics Co., Ltd.
86% by weight of an olefin resin containing a non-crosslinked homopolypropylene resin (melting point MI = 10) and a silane crosslinkable homopolypropylene (manufactured by Mitsubishi Chemical Corporation, XPM800H) in a weight ratio of 7: 3 as a thermoplastic resin. Was melt-kneaded with a twin-screw extruder having a cylinder temperature set at 290 ° C., extruded into strands, and then cut to obtain mixed pellets. The pellets were immersed in hot water at 100 ° C. for 4 hours to perform a crosslinking treatment.

In the same manner as in Example 1, the mixed resin pellets were supplied to a 50 mm single-screw extrusion blow molding machine.
Extrusion blow molding was performed at a rate of g / hr and an extrusion temperature of 290 ° C. The obtained hollow molded body was dissolved in hot xylene, and the form of the remaining liquid crystal resin was observed with an optical microscope. As a result, a part of the liquid crystal resin remained in a fibril state.

(Example 4) As a liquid crystal resin, 14% by weight of Rodrun LC3000 (transition temperature 180 ° C) manufactured by Unitika Ltd., and as a thermoplastic resin, a non-crosslinked high-density polyethylene resin (melting point MI = 1) and a silane-crosslinkable polyethylene (Mitsubishi Chemical Corporation, HF700N) in a weight ratio of 8: 2, and a mixture of 86% by weight of an olefin resin was melt-kneaded in a twin-screw extruder having a cylinder temperature of 200 ° C. to obtain a strand. , And then cut to obtain a mixed pellet.

The pellets were immersed in hot water at 100 ° C. for 4 hours to carry out a crosslinking treatment. In the same manner as in Example 2, this mixed resin pellet was supplied to a 50 mm single screw extrusion blow molding machine, and extrusion blow molding was performed at a rate of 10 kg / hour and an extrusion temperature of 220 ° C.

The hollow molded body was fractured under liquid nitrogen, and the fracture surface was observed by an electron microscope. As a result, it was found that the liquid crystal resin was dispersed in a fibril form in the polyethylene forming the matrix.

Example 5 The same as Example 1 except that the liquid crystal resin was blended at a ratio of 20% by weight.

(Comparative Example 1) A polypropylene pellet alone was supplied to a 50 mm single screw extrusion blow molding machine without mixing a liquid crystal resin, and blow molding was carried out in the same manner as in Example 1 except for the other points. Obtained.

Comparative Example 2 A hollow molded body was obtained in the same manner as in Example 3, except that the liquid crystal resin was not mixed.

Comparative Example 3 A hollow molded body was obtained in the same manner as in Example 4 except that no liquid crystal resin was mixed.

Comparative Example 4 The same procedure as in Example 1 was carried out except that the liquid crystal resin was blended at a ratio of 60% by weight.
Resin breakage occurred during blow-up, and molding was not possible.

Comparative Example 5 A hollow molded body was obtained in the same manner as in Example 1 except that the die gap was 0.5 mm and the blow ratio was about 8 times. It has opened.

(Evaluation of Molded Articles) The hollow molded articles obtained in Examples 1 to 5 and Comparative Examples 1 to 3 were left in an oven at 140 ° C. for 5 minutes to evaluate the presence or absence of deformation due to heat.

A dumbbell No. 2 was cut out from the obtained hollow molded product, and a tensile test was performed in accordance with JIS K7113. The crosshead speed was 10 mm / min. The tensile modulus was determined from the initial slope of the obtained SS curve, and the tensile strength was determined from the maximum value. Table 1 shows the results.

[0059]

[Table 1]

As is clear from Table 1, in Comparative Examples 1 to 3 in which no liquid crystal resin was used, the obtained hollow molded articles did not retain their shapes in the heat-resistant deformation test, and the side faces were partially bent. I was In addition, the tensile strength was 31.7 MPa or less, the tensile modulus was as low as 1.6 GPa, and the mechanical strength was not sufficient.

On the other hand, in Examples 1 to 4, in the heat deformation test, the shape did not change or only a slight deformation was observed, and the tensile elastic modulus was determined by using polyethylene as the thermoplastic resin. 1.6 GPa even if
As described above, it is understood that the tensile strength is as high as 32.6 MPa or more, and the mechanical strength is sufficiently large.

[0062]

According to the first aspect of the present invention, blow molding is performed so as to include 1 to 40% by weight of a liquid crystal resin and 60 to 99% by weight of a thermoplastic resin and to have a blow ratio of 1.05 to 5. Since this is a synthetic resin hollow molded body, the hollow molded body has excellent heat deformation resistance and sufficient mechanical strength.

Further, since the synthetic resin hollow molded article is made of liquid crystal resin and has improved heat resistance and mechanical strength, it can be easily re-melted, and therefore can be recycled as a raw material of the same molded article. And it can be easily reused for other molded articles. Therefore, it is possible to provide a synthetic resin hollow molded body having high heat deformation resistance and mechanical strength and suitable for recycling.

According to the second aspect of the present invention, since the liquid crystal resin is dispersed in the thermoplastic resin in the form of fibrils, the reinforcing effect of the liquid crystal resin is enhanced, and the rigidity and the mechanical strength of the synthetic resin are further increased. A hollow molded article can be provided.

According to the third aspect of the present invention, since the thermoplastic resin is a polyolefin resin and a polyolefin resin having excellent mechanical properties is used, in addition, the polyolefin resin is crosslinked with a non-crosslinked polyolefin resin. Since the polyolefin resin is used in combination with the polyolefin resin, it is possible to provide a synthetic resin hollow molded article having even more excellent mechanical strength.

Claims (3)

[Claims] 1. A synthetic resin hollow molded article obtained by blow molding, comprising 1 to 40% by weight of a liquid crystal resin and 60 to 99% by weight of a thermoplastic resin, and blow molded at a blow ratio of 1.05 to 5. A hollow molded article made of synthetic resin, characterized in that it is made. 2. The synthetic resin hollow molded article according to claim 1, wherein the liquid crystal resin is dispersed in a fibril shape in a thermoplastic resin. 3. The synthetic resin hollow molded article according to claim 1, wherein the thermoplastic resin contains a non-crosslinked polyolefin resin and a crosslinkable polyolefin resin.