JP7232690B2 - Method for manufacturing resin foam molding - Google Patents

Description

TECHNICAL FIELD The present invention relates to a resin foam molded article and a method for producing a resin foam molded article.

2. Description of the Related Art Conventionally, resin foam molded articles called expanded polystyrene have been used for various purposes.
This resin foam molded article called styrene foam is usually produced by a method in which resin foam particles made of polystyrene resin are heated in a mold for secondary expansion and heat fusion of the resin foam particles. It is

In recent years, this type of resin foam molded article has been required to have heat resistance and flame retardancy. It has been studied to configure a resin foam molded body with.

JP 2012-116968 A

As described above, resin foam moldings are required to have heat resistance and flame retardancy, but such demands are not fully satisfied. Accordingly, an object of the present invention is to provide a resin foam molded article having excellent heat resistance and flame retardancy.

In order to solve the above problems, the present invention provides a resin foam molded article composed of a polyarylene sulfide-based resin composition containing a polyarylene sulfide-based resin, which has a crystallinity of 20% or more and an expansion ratio of To provide a resin foam molded article that is twice or more.

The present invention comprises a first step of producing resin particles composed of a polyarylene sulfide-based resin composition containing a polyarylene sulfide-based resin, and impregnating the resin particles obtained in the first step with a foaming agent to foam. a second step of obtaining flexible resin particles; and heating and expanding the expandable resin particles obtained in the second step to form expanded resin particles and fusing the expanded resin particles together to perform resin foam molding. The present invention provides a method for producing a resin foam molded article by performing a third step of producing a body to produce a resin foam molded article.

According to the present invention, it is possible to obtain a polyarylene sulfide-based resin foam molded article having excellent heat resistance and flame retardancy.

FIG. 1 is a schematic diagram showing an apparatus for producing resin particles as a raw material for a resin foam molded article. FIG. 2 is an enlarged view of a main portion of the apparatus of FIG. 1; FIG. 3 is a cross-sectional view taken along the line AA of FIG. 2;

Embodiments of the present invention will be described below. A method for obtaining a resin foam molded article using resin particles composed of a polyarylene sulfide-based resin composition containing a polyarylene sulfide-based resin will be described below.
The resin particles of this embodiment are composed of a polyarylene sulfide-based resin composition containing a polyarylene sulfide-based resin. The resin particles of the present embodiment are used to form part or all of a resin foam molded article.

The specific form of the foamed resin article is not particularly limited, and for example, a plurality of foamed resin particles formed by expanding the resin particles are heat-sealed and integrated in a mold. and a composite resin foam molded article including a plurality of the resin foam particles and an adhesive for adhering the resin foam particles together, wherein the resin foam particles are hardened with the adhesive. be done.
These resin foam moldings exhibit excellent heat resistance and flame retardancy because they contain polyarylene sulfide-based resins in their constituent materials.

The polyarylene sulfide-based resin contained in the polyarylene sulfide-based resin composition is a homopolymer as long as it contains an arylene sulfide represented by the following general formula (1) as a main structural unit. may also be a copolymer.

-(Ar-S)- (1)

Here, "Ar" in the formula represents an arylene group.

When a copolymer is employed as the polyarylene sulfide-based resin, the copolymer may be a block copolymer comprising a polyarylene sulfide block of arylene sulfide and a polyamide block.
The polyarylene sulfide block and the block constituting the block copolymer may be polycarbonate, polysulfone, or the like.

Examples of the arylene sulfide include phenylene sulfides such as p-phenylene sulfide, m-phenylene sulfide and o-phenylene sulfide.
The arylene sulfide may be, for example, phenylene sulfide sulfone, phenylene sulfide ketone, phenylene sulfide ether, diphenylene sulfide, and the like.

The arylene group of the arylene sulfide may be substituted with a substituent.

When a copolymer is employed as the polyarylene sulfide-based resin, for example, it may be random copolymerization containing arylene sulfide as described above and structural units other than arylene sulfide.
When a copolymer is employed as the polyarylene sulfide-based resin, for example, it may be a copolymer having two or more of the above arylene sulfides as structural units.

Aromatic dihalogen compounds such as 4,4'-dichlorodiphenylsulfone are often used as starting materials for the polyarylene sulfide-based resins, and halogen groups may remain in the molecule, or the ends may be halogen groups. Oligomers may be mixed. Such a halogen group can also be a factor in generating hydrogen halide by dehalogenation reaction. Therefore, the halogen content of the polyarylene sulfide resin contained in the resin particles is preferably 1500 ppm or less.
The halogen content of the polyarylene sulfide resin is more preferably 1200 ppm or less, more preferably 900 ppm or less.

The halogen content of the polyarylene sulfide-based resin can be determined, for example, by a method such as combustion ion chromatography.
In the resin particles, not only the halogen content of the polyarylene sulfide resin contained is within the above range, but also when the halogen content of the resin particles themselves is measured, the halogen content is within the above range. It is preferable that it is within the range.
The same applies to the resin foam molded article.

The polyarylene sulfide-based resin in the present embodiment preferably contains phenylene sulfide as a main structural unit among the structural units.
The proportion of phenylene sulfide in the constituent units of the polyarylene sulfide-based resin is preferably 75% by mass or more, more preferably 90% by mass or more.
It is particularly preferable that the polyarylene sulfide-based resin is a polyphenylene sulfide resin substantially composed only of phenylene sulfide.
Among o-phenylene sulfide, p-phenylene sulfide and m-phenylene sulfide, the polyphenylene sulfide resin is preferably mainly composed of p-phenylene sulfide and m-phenylene sulfide.
In the polyphenylene sulfide resin, the total proportion of p-phenylene sulfide and m-phenylene sulfide is preferably 75% by mass or more, more preferably 90% by mass or more.

By the way, resins with an oxygen index (LOI) exceeding 26 specified in JIS K 7201-2:2007 "Plastics-Testing method for flammability by oxygen index-Part 2: Test at room temperature" are generally Judged as flame retardant.
Regarding this, the polyphenylene sulfide resin has an oxygen index of more than 30, which is determined using a type I test piece (bar-shaped sample with a thickness of 4 mm and a width of 10 mm) according to the same standard, and has excellent flame retardancy. Polyarylene sulfide resins other than polyphenylene sulfide resins also exhibit excellent flame retardancy. Therefore, the resin foam molded article of the present embodiment can exhibit excellent flame retardancy.

The polyarylene sulfide-based resin composition constituting the resin particles may contain a flame retardant, if necessary, depending on the required flame retardancy.
In addition, the polyarylene sulfide-based resin composition includes a resin other than the polyarylene sulfide-based resin, an inorganic filler, a plasticizer, a crystal nucleating agent, a lubricant, an antioxidant, an antistatic agent, an ultraviolet absorber, a light stabilizer, A coloring agent, an antibacterial agent, an anti-rat agent, an insect repellent, etc. may be contained.
In order to allow the resin particles to remarkably exhibit the properties derived from the polyarylene sulfide-based resin, the content of components other than the polyarylene sulfide-based resin in the polyarylene sulfide-based resin composition is 20% by mass or less. preferably 15% by mass or less, and even more preferably 10% by mass or less.

The size and shape of the resin particles in the present invention are not particularly limited, but in consideration of mold filling properties during molding and productivity such as the time for containing the foaming agent, the diameter of the resin particles is 0.3 mm to 2 mm in terms of spheres. is preferred, and 0.5 mm to 1.5 mm is more preferred.

When the crystallinity of the resin particles is less than 20%, the resin particles have high foamability and moldability, and can be advantageous in exhibiting light weight and heat insulating properties.
The crystallinity of the resin particles is more preferably less than 10%, even more preferably less than 5%, and particularly preferably less than 3%.

The foamed resin article of the present embodiment comprises a first step of producing resin particles composed of a polyarylene sulfide-based resin composition containing a polyarylene sulfide-based resin, and foaming the resin particles obtained in the first step. a second step of impregnating an agent to obtain expandable resin particles; and heating and expanding the expandable resin particles obtained in the second step to form expanded resin particles and to melt the expanded resin particles together. It is produced by carrying out a third step of forming a resin foam molded body by attaching the resin foam.

In the first step, the resin particles having the crystallinity as described above can be produced, for example, by performing the following steps.
(a) A thermal melting step of heating and melting a polyarylene sulfide-based resin composition containing a polyarylene sulfide-based resin and other components in a predetermined ratio.
(b) quenching the hot-melt polyarylene sulfide-based resin composition obtained in the hot-melting step to form a solidified product with the polyarylene sulfide-based resin composition, and A granulation process for producing finely expanded particles (hereinafter also referred to as “raw particles”).

The heat melting step can be performed, for example, by kneading the polyarylene sulfide-based resin composition while heating it to a temperature equal to or higher than the melting point of the polyarylene sulfide-based resin using a device such as an extruder or a kneader.
The hot melting step is preferably carried out using a single-screw extruder or a twin-screw extruder.

The granulation step can be carried out by a method such as a water ring hot cut method or an underwater hot cut method.
In the water ring hot cut method and the underwater hot cut method, a melt-kneaded product of a polyarylene sulfide resin composition is prepared with an extruder, and the melt-kneaded product is extruded from a granulation die attached to the tip of the extruder. A method of performing a so-called "hot cut granulation method" in which a molten kneaded product extruded from the granulation die is quickly cut with a rotating cutter to form granules in the presence of cooling water. is.

In the water ring hot cut method, the cutting of the melt-kneaded product itself is performed in the air, and the cut and granulated melt-kneaded product is brought into contact with cooling water immediately after cutting. It is carried out by extruding the melt-kneaded material into cooling water and cutting the melt-kneaded material into granules in the cooling water.
In any of these, the melt-kneaded material can be cooled quickly, which is advantageous in making the resulting raw grains in a state of low crystallinity.
In order to lower the crystallinity of the raw grains, it is preferable to provide a temperature difference of 250° C. or more between the temperature of the melt-kneaded material (T1) and the temperature of the cooling water (T2).

An example of an embodiment of this granulation step will be described with reference to the drawings.
FIG. 1 shows a granulating apparatus T used in such a granulating process, and FIG. 2 shows a granulating die 1 for the water ring hot cut method and its peripheral equipment.
FIG. 3 is a cross-sectional view taken along the line AA in FIG. 2, and shows a front view of the die body 10 (also called a die plate).

As shown in the figure, the granulating apparatus T includes an extruder 2 having a granulating die 1 attached to its tip, and a melt-kneaded material 20 (molten a chamber 4 for accommodating a cutter 3 for cutting the polyarylene sulfide-based resin composition) and forming a space 4b covering the front surface (resin discharge surface 10f) of the granulating die 1 in the extrusion direction; It has

As shown in the figure, the granulator T includes a die body 10 (also called a die plate) and a die holder 11 fixed to the tip side of the extruder 2. The die body 10 is fixed to the tip side of the die holder 11 , and a part of the tip side of the die holder 11 to which the die body 10 is fixed is movable and functions as a diverter valve 13 .

The die holder 11 has an internal channel 11a that communicates with the cylinder of the extruder 2, and is configured to supply the melt-kneaded material 20 from the extruder 2 toward the die body 10 through the internal channel. there is

The die body 10 branches the melt-kneaded material 20 supplied through the internal flow path 11a of the die holder 11 so as to flow through a plurality of resin flow paths 14 extending along the extrusion direction and parallel to each other. The melt-kneaded material 20 is discharged from a plurality of die holes 15 opening at the tip of each resin channel 14 .

On the resin discharge surface 10f of the die body 10, the outlets of the melted and kneaded material 20 from the respective resin passages 14 are arranged on the same circumference at regular intervals, and a plurality of the die holes 15 are arranged in groups in each of them. It is

The cutter 3 includes a substrate 31 arranged to face the resin ejection surface 10f, a plurality of cutting blades 32 arranged to protrude from the substrate 31 toward the resin ejection surface 10f, and the substrate. and a rotating shaft 33 that rotates 31 .
The rotating shaft 33 passes through the center of the circumference where the outlet of the resin flow path 14 is arranged and extends along a direction (extrusion direction) perpendicular to the resin discharge surface 10f. It is connected to the substrate 31 so as to rotate the substrate 31 while maintaining it parallel to the resin discharge surface 10f.
The plurality of cutting blades 32 are arranged so that the cutting edge extends in a direction radially extending from the connecting position of the rotating shaft 33 and the substrate 31, and the cutting edge moves circularly while sliding on the resin discharge surface 10f. is distributed to
The cutter 3 is arranged so that when the substrate 31 is rotated by the rotating shaft 33 , the blade edge cuts the molten kneaded material 20 extruded from the die hole 15 into granules.

In the granulator T, the melt-kneaded material cut into granules and the cooling water AQ are brought into contact with each other in the space 4b in the chamber 4. As shown in FIG.
A pipeline 5 for supplying the cooling water AQ is connected to the granulating die 1 , and one end of the pipeline 5 is connected to a water tank 7 via a water pump 6 .

The resin discharge surface 10f is provided with a slit 17 having a circular opening that extends outside the die hole 15. As shown in FIG.
In the chamber 4 of the present embodiment, the cooling water AQ is discharged from the slit 17 to form a water film SP by the cooling water AQ. The molten kneaded material 20 immediately after discharged from 15 and the cooling water AQ are prevented from coming into contact with each other.
In the chamber 4 of the present embodiment, the molten kneaded material 20 cut into granules by the cutter 3 is thrown radially outward by the cutting blade 32, collides with the water film SP, and is instantly cooled. It's like

In the granulator T, the molten kneaded material 20 that has been cooled and solidified is discharged from the chamber 4 together with the cooling water AQ as the raw particles B, and is separated from the cooling water by specific gravity separation in the separation tank 8. .
Normally, the obtained raw grains B have a high specific gravity with respect to water, so they are collected from the bottom of the separation tank 8 .
The cooling water AQ separated in the separation tank 8 can be cooled by a chiller (not shown), for example, and then returned to the water tank 7 for reuse.

The underwater hot-cutting method in this embodiment is carried out with the same apparatus as the water-ring hot-cutting method except that the die holes are always in contact with the cooling water in the chamber.

Since the polyarylene sulfide-based resin has a high melting point, the resin discharge surface becomes hot in both methods. It can be said that the method implemented by the method is more efficient than the method implemented by the underwater hot cut method.

Incidentally, the method for producing raw grains is not limited to the method described above.
The raw grains in this embodiment are formed by continuously extruding the melt-kneaded material into strands from a die hole of a die attached to the tip of the extruder, immersing the strands in a cooling water tank, and then cutting them with a pelletizer. It may be made by a strand-cut method such as

The degree of crystallinity of the resin particles and the resin foam molding in this embodiment can be obtained as follows. As for the resin particles, the resin particles are pulverized or chopped with a knife to form fine particles (powder), which is used as a measurement sample. Also for the resin foam molded article, a fine granular (powder) measurement sample is collected from a portion composed of resin particles.
The crystallinity of the resulting measurement sample can be determined using a differential scanning calorimeter (DSC) as follows.

(Method for measuring crystallinity)
Crystallinity is measured based on the method described in JIS K7122:2012 "Method for measuring transition heat of plastic".
However, the sampling method and temperature conditions are as follows.
Using a differential scanning calorimeter model DSC6220 (manufactured by SII Nanotechnology Co., Ltd.), the bottom of an aluminum measurement container was filled with about 6 mg of a sample for measurement without any gaps, and the temperature was adjusted to 30 at a nitrogen gas flow rate of 20 mL/min. C. for 2 minutes, and the DSC curve is obtained when the temperature is raised from 30.degree. C. to 350.degree. C. at a rate of 10.degree.
Alumina is used as the reference material at that time.
The crystallinity is defined as the difference between the heat of fusion (J/g) determined from the area of the melting peak and the heat of crystallization (J/g) determined from the area of the crystallization peak, which is the perfect crystallinity of the polyarylene sulfide resin. It is obtained by dividing by the theoretical heat of fusion (for example, "146.2 J/g" for polyphenylene sulfide resin).
The heat of fusion and the heat of crystallization are calculated using analysis software attached to the apparatus.
Specifically, the heat of fusion is calculated from the straight line connecting the point where the DSC curve departs from the high-temperature side baseline and the point where the DSC curve returns to the low-temperature side baseline, and the portion surrounded by the DSC curve. .
The heat of crystallization is calculated from the area surrounded by the straight line connecting the point where the DSC curve departs from the baseline on the low temperature side and the point where the DSC curve returns to the high temperature side, and the area surrounded by the DSC curve.
That is, the degree of crystallinity is obtained from the following equation.

Crystallinity (%) =
((heat of fusion (J/g) - heat of crystallization (J/g))/146.2 (J/g)) x 100

The resin foam molding in the present embodiment is superior in strength and heat resistance when the polyarylene sulfide-based resin is contained in a state of high crystallinity.
Therefore, it is preferable that the polyarylene sulfide-based resin composition in the resin foam molded article has a degree of crystallinity of 10% or more. The degree of crystallinity of the resin foam molding is preferably 15% or more, more preferably 20% or more.

In the present embodiment, as the second step, a foaming agent impregnation step of impregnating raw grains obtained in the granulation step with a foaming agent to form expandable resin particles can be performed.
A specific method for producing expandable resin particles in the step of impregnating the foaming agent includes, for example, a method in which raw particles and a physical foaming agent are brought into contact with each other in a pressurized atmosphere in a pressure vessel such as an autoclave. . Examples of the physical foaming agent include hydrocarbons such as butane and pentane, halides thereof, and inorganic gases such as nitrogen, argon, and carbon dioxide.
Among them, the physical foaming agent with which the raw grains are impregnated is preferably carbon dioxide, which has excellent solubility in the polyarylene sulfide-based resin.
The blowing agent impregnation step may be performed under supercritical conditions exceeding the critical point of carbon dioxide in order to enhance the impregnation of carbon dioxide into the raw grains.

In the third step of the present embodiment, the raw particles (expandable resin particles) impregnated with the foaming agent are heated to a temperature equal to or higher than the glass transition temperature of the polyarylene sulfide resin to form an expanded state (expanded resin particles). ) can be implemented in such a way that
That is, in the third step in the present embodiment, for example, the raw grains containing the foaming agent are filled in the mold and heated to foam the raw grains charged in the mold, so that the raw grains are expanded into the mold. It can be carried out by a method of forming a plurality of resin foamed particles and thermally bonding the resin foamed particles to form a resin foamed article (bead foamed article).

When foaming the expandable resin particles to produce a resin foam molded article, it is preferable to perform atmospheric heating at 150° C. or more and 200° C. or less, and the expandable resin particles are heated using superheated steam at such a temperature. is preferably heated.

The apparent density of the resin foam molded article produced as described above can be adjusted by adjusting the amount of expandable resin particles filled in the mold, and the apparent density of the resin foam molded article ranges from 50 kg/m ³ to 500 kg/m ³ . is preferred, and 100 kg/m ³ to 400 kg/m ³ is more preferred.
The apparent density of the resin foam molding is preferably 200 kg/m ³ or less considering the strength, heat deformation resistance, and flame retardancy of the resin foam molding. is preferably

The apparent density of the resin foam molded article can be determined, for example, as follows.
Cut out a sample of 100 cm ³ or more by cutting so as not to change the original cell structure as much as possible, and condition this sample for 16 hours in a JIS K7100: 1999 symbol 23/50, class 2 environment. is measured, and the density is calculated by the following formula.

Apparent density (kg/m ³ ) = sample mass (kg)/sample volume (m ³ )

For the dimensional measurement of the sample, for example, "DIGIMATIC" CD-15 type manufactured by Mitutoyo Co., Ltd. can be used.

The expansion ratio of the resin foam molded article is preferably 1.5 times or more, more preferably 2 times or more, and even more preferably 3 times or more.
The expansion ratio of the resin foam molded product is preferably high in consideration of lightness, but is preferably 50 times or less, more preferably 40 times or less, and 30 times or less in consideration of strength and productivity. It is even more preferable to have

_The expansion ratio of the resin foam molding is _{the value (ρ 0 /} ρ ₁ ).
The density (ρ ₀ ) of the resin composition can be determined by "Method A (submersion method in water)" in JIS K7112:1999 "Plastics-Determination of density and specific gravity of non-foamed plastics".

In addition, it is preferable that the foamed resin article has a dense structure with an average cell diameter of 100 μm or less. The average cell diameter is more preferably 90 μm or less, and even more preferably 80 μm or less.

The average bubble diameter can be obtained as follows.
(How to find the average bubble diameter)
If the foamed resin article is composed of resin foamed particles, the size of the cells at the interfaces between the resin foamed particles may differ greatly from the inside. Avoid measuring.
That is, the average cell diameter can be measured based on the image obtained by photographing a cross section obtained by cutting the foamed resin bead into two at the approximate center with a scanning electron microscope. Specifically, a photograph of the cross section is taken with a scanning electron microscope (for example, S-3000N manufactured by Hitachi, Ltd. or S-3400N manufactured by Hitachi High-Technologies Corporation).
The photographing is performed by photographing the central portion of each of four foamed resin beads randomly selected from the foamed resin beads that are considered to be divided into two at the center.
Print the photographs taken on A4 paper, two images each horizontally and vertically, for a total of four images, and calculate the average chord length (t) of the bubbles from the number of bubbles on an arbitrary straight line (length 60 mm) parallel to the vertical and horizontal directions. Calculated by the formula. However, an arbitrary straight line should be drawn so that bubbles do not come into contact with each other as much as possible (if they do, they are included in the number of bubbles).
Measurement shall be made at 6 points each in length and width for each image.

Average chord length t (mm) = 60/(number of bubbles x magnification of photo)

Then, the bubble diameter in each direction is calculated by the following equation.

D (mm) = t/0.616

Furthermore, let the square root of the product of them be the average bubble diameter.

Average bubble diameter (mm) = (D length x D width) ^1/2

The resin foam molded article has excellent flame retardancy, excellent heat resistance, and light weight.
Applications of the resin foam molding include, for example, moving bodies such as automobiles, trains, ships, and airplanes; televisions, audio equipment, refrigerators, washing machines, vacuum cleaners, room air conditioners, heaters, ovens, microwave ovens, rice cookers, It can be used in various applications such as home electric appliances; electronic devices such as smartphones, tablets, and personal computers;
The expanded resin particles and expanded resin article of the present invention can also be used for purposes other than those described above, and are not limited to the examples given in this specification.

EXAMPLES Next, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these.

(Example 1)
Polyphenylene sulfide resin (trade name “Ryton QC160P”, manufactured by Solvay, melting point = 279 ° C., glass transition temperature = 91 ° C.) is dried at a temperature of 130 ° C. for 4 hours or more in a dehumidifying dryer, and extruded (15 mm twin screw The melt-kneaded mixture was melt-kneaded at a resin temperature of 302° C. using an extruder (L/D=40), and the melt-kneaded product was extruded into a string.
After introducing the string-shaped melt-kneaded material into a cooling water tank storing cooling water at 14° C. and cooling it with water to obtain a strand, the strand is cut with a small pelletizer to have a diameter of about 1 mm and a length of 1.5 mm. 5 mm resin particles were obtained.
The crystallinity of the obtained resin particles was 7.1%.
The resin particles are filled in an autoclave, brought into contact with carbon dioxide as a foaming agent under a pressure of 4.0 MPa, and the pressure is maintained for 24 hours to produce resin particles impregnated with carbon dioxide (expandable resin particles). Obtained.
The foaming agent content in these expandable resin particles was 3.5% by mass.
Next, the obtained expandable resin particles are filled in a mold having a rectangular parallelepiped molding space of 200 mm long×200 mm wide×10 mm thick, and heated with superheated steam of 0.5 MPa (152° C.) for 20 seconds. to obtain a resin foam molded article having an apparent density of 300 kg/m ³ (expansion ratio: about 4.5 times).

(Example 2)
A foamed resin article was produced in the same manner as in Example 1, except that the melt-kneaded product was granulated by a water ring cut method.
The crystallinity of the resin particles obtained here was 8%, and the apparent density of the finally obtained resin foam molding was 600 kg/m ³ (expansion ratio: about 2.2 times). .

(Reference example 1)
After obtaining resin particles in the same manner as in Example 1, except that the temperature of the cooling water tank was 55° C., a foamed resin article was produced. The degree of crystallinity of the obtained resin particles was 14%, and it was not possible to obtain a resin expansion molding with expandable resin particles obtained by impregnating these resin particles with a foaming agent.

From the above, it can be understood that the present invention provides a resin foam molded article having excellent heat resistance and flame retardancy.

1: granulation die, 2: extruder, 3: cutter, 4: chamber, 15: die hole, 20: melt-kneaded product, AQ: cooling water, S: resin particles, SP: water film

Claims (6)

a first step of producing resin particles composed of a polyarylene sulfide-based resin composition containing a polyarylene sulfide-based resin;
a second step of impregnating the resin particles obtained in the first step with a foaming agent to obtain expandable resin particles;
and a third step of heating and expanding the expandable resin particles obtained in the second step to form expanded resin particles and fusing the expanded resin particles together to produce a resin expansion molded article. to produce a resin foam molded body ,
In the polyarylene sulfide-based resin composition, the content of the polyarylene sulfide-based resin is 80% by mass or more, and the proportion of phenylene sulfide in the constituent units of the polyarylene sulfide-based resin is 90% by mass or more. ,
In the first step, a melt-kneaded product of the polyarylene sulfide-based resin composition is prepared by an extruder, and the melt-kneaded product is extruded into the air from a die attached to the extruder and cut into granules, The cut and granular melt-kneaded product is blown toward cooling water and water-cooled to produce the resin particles having a crystallinity of less than 10%, and the temperature (T1) of the melt-kneaded product and the cooling A method for producing a resin foam molded article having a temperature difference of 250° C. or more from the temperature of water (T2) . a first step of producing resin particles composed of a polyarylene sulfide-based resin composition containing a polyarylene sulfide-based resin;
a second step of impregnating the resin particles obtained in the first step with a foaming agent to obtain expandable resin particles;
and a third step of heating and expanding the expandable resin particles obtained in the second step to form expanded resin particles and fusing the expanded resin particles together to produce a resin expansion molded article. to manufacture a resin foam molded body ,
In the polyarylene sulfide-based resin composition, the content of the polyarylene sulfide-based resin is 80% by mass or more, and the proportion of phenylene sulfide in the constituent units of the polyarylene sulfide-based resin is 90% by mass or more. ,
In the first step, a melt-kneaded product of the polyarylene sulfide-based resin composition is prepared by an extruder, the melt-kneaded product is extruded from a die attached to the extruder into cooling water, and cooled in the cooling water. to produce the resin particles having a degree of crystallinity of less than 10%. A method for producing a resin foam molding with a temperature difference . a first step of producing resin particles composed of a polyarylene sulfide-based resin composition containing a polyarylene sulfide-based resin;
a second step of impregnating the resin particles obtained in the first step with a foaming agent to obtain expandable resin particles;
and a third step of heating and expanding the expandable resin particles obtained in the second step to form expanded resin particles and fusing the expanded resin particles together to produce a resin expansion molded article. to produce a resin foam molded body ,
In the polyarylene sulfide-based resin composition, the content of the polyarylene sulfide-based resin is 80% by mass or more, and the proportion of phenylene sulfide in the constituent units of the polyarylene sulfide-based resin is 90% by mass or more. ,
In the first step, a melt-kneaded product of the polyarylene sulfide-based resin composition is prepared by an extruder, and the melt-kneaded product is extruded into the air from a die attached to the extruder to cool the strand. The resin particles having a crystallinity of less than 10% are produced by immersing in water, cooling with water, and then cutting into granules, and the temperature of the melt-kneaded product is between the temperature (T1) of the melt-kneaded product and the temperature of the cooling water (T2). There is a temperature difference of 250°C or more in the manufacturing method of the resin foam molding. 4. The production of the resin foam molded article according to claim 1, wherein in the second step, an inert gas is used as the foaming agent, and the resin particles are impregnated with the inert gas under pressure. Method. 5. The method for producing a foamed resin article according to claim 1, wherein in the third step, the expandable resin particles are heated at an ambient temperature of 150[deg.] C. or higher and 200[deg. ] C. or lower. 2. The resin foam molded article having a crystallinity of 20% or more, an expansion ratio of 2 times or more, and an average cell diameter observed in a cross section of 100 μm or less in the third step is manufactured in the third step. 6. A method for producing a resin foam molded article according to any one of items 1 to 5.

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