JPH02215506A - Manufacture of granular polyphenylene sulfide resin composition - Google Patents

Abstract

PURPOSE:To manufacture a pellet of PPS composition without cutout or pulverization of the pellet and of good shape by granulating a resin composition composed of polyphenylene sulfide composition (PPS), a fiber reinforcing material or/and another inorganic filler by means of an underwater cutting granulator with a pipe die mounted. CONSTITUTION:PPS is of extremely high melting temperature, usually 300 deg.C or higher in the extrusion process. Also, melting viscosity is suddenly lowered at 280 deg.C, a melting point. Granulation of resin of such properties can be carried out by the underwater cutting method using a pipe die. Said pipe die 1 is of a structure wherein a passage 4 for heat transfer medium is provided on the periphery of each of nozzles 3 provided on a dice surface 2. Even material of comparatively low viscosity can be made into a pellet of good shape without pulverization or cutout. The composition of comparatively low viscosity is measured by a capillary rheometer, and the composition of less than 10<4> poise in the temperature area of 300 - 380 deg.C and also in the area of shearing speed 10<2> - 10<4>/sec. is preferred.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a granular product of a rephenylene sulfide resin composition (hereinafter abbreviated as PPS composition) mainly for injection molding. .

[Conventional technology]

Demand for PPS compositions has been increasing in recent years as a heat-resistant engraer with excellent cost performance.

Its uses are mainly automotive electrical components, home appliance parts,
With the proliferation of electronic components, it is attracting attention as an alternative material to epoxy resin as a packaging material for electronic devices such as ICs. For these uses, the PPS composition is supplied in the form of granules called pellets, which are fed into an injection molding machine and molded into the required part shape.

Although PPS has many excellent features, it has a major drawback of being brittle. This brittle characteristic is
This is further doubled in compositions filled with mineral fillers.

The brittleness of the pps or Fipps compositions described above is a major hindrance in the manufacturing process of the above pellets. Conventionally, pellets of PPS compositions have been produced by placing strands of the composition in a molten state discharged through a die hole of an extruder on a belt conveyor, cooling and solidifying them, and then using a cutter with a rotary blade called a pelletizer for two or more steps. The most common method is to cut it into six utai lengths.

However, with this strand cutting method, a large amount of chips and powder were generated due to impact damage during cutting, and the shape of the pellets was poor.

As a method for improving the drawbacks of this strand cut method, a granulation method called hot die face cut has recently come into widespread use. In this granulation method, the resin cut out from the die of an extruder is cut at high speed in a molten state using a nine-blade knife in contact with the die surface, and then guided by air to a cooler called a cyclone where it is cooled. be. The pellets obtained using this method are of good quality with few chips or powder, but after being cut with a knife, they are air transported at high speed, so the pellets tend to become flattened or collide with walls in transport pipes or cyclones. It has drawbacks such as sometimes generating fine powder, making it difficult to use during injection molding processing.

[Problem to be solved by the invention]

The object of the present invention is to obtain pellets of a PPS composition that are free from chipping or powdering and have a uniform shape.

[Rounding method to solve the problem]

The present invention is equipped with an underwater cut granulator at the tip of the extruder,
In addition, the problem can be solved by using a die with high thermal efficiency as the structure of the die of the granulator.

That is, the present invention is characterized in that a resin composition comprising pps and a fibrous reinforcing material and/or other inorganic filler is granulated using an underwater cutting granulator equipped with a pipe die. A method for producing a polyphenylene sulfide resin composition is provided.

In addition to the above-mentioned strand cut and hot die face cut, underwater cut methods using a core die or drill die are known as resin granulation methods. However, in such an underwater cutting method, polyethylene, EVA, etc., which have a relatively high melt viscosity and whose melt viscosity can be relatively easily controlled depending on the operating conditions of the extruder, are suitable. on the other hand,
PPS has an extremely high melting temperature, typically 3
00℃ or higher. Furthermore, the melt viscosity is the melting point 28
The viscosity decreases rapidly at 0°C, and the viscosity is low. It is impossible to granulate resin with such properties using the conventional underwater cutting method, such as a core die (Figure 1) or a drill die (Figure 2). We discovered that this was possible for the first time by using a similar pipe die. Such a nozzle die has a structure in which a heat medium passage is provided around each nozzle provided on the die surface.

By underwater cutting method using this pipe die, PPS
Even with a composition of relatively low viscosity, it is now possible to produce pellets with good shape and no powder or chips. The composition described here has a relatively low viscosity, as measured by a two-cavity rheometer, and has a processing temperature of 300 to 380°C and a shear rate of 102 to 10' 1/s·C.
3 and less than 104 poise is preferred.

The production method of the present invention is suitable for granulating a PPS composition for sealing electronic devices such as ICs, which has an extremely low melt viscosity. still,
It is particularly preferable that the PPS composition has a melt viscosity of 10 poise or less as measured by the above-mentioned method.

The pps that can be used in the present invention preferably contains 90 moles or more of the structural unit represented by the general formula %s-; if the amount is less than 90 moles, it is difficult to obtain a composition with excellent properties. Polymerization methods for this polymer include a method in which P-dichlorobenzene is polymerized in the presence of sulfur and sodium carbonate, a method in which P-dichlorobenzene is polymerized in the presence of sulfur and sodium carbonate, and a method in which P-dichlorobenzene is polymerized in the presence of sodium sulfide, sodium hydrosulfide and sodium hydroxide, or hydrogen sulfide and sodium hydroxide in a polar solvent. Examples include self-condensation of P-chlorothiophenol, and polymerization of sodium sulfide and P-dichlorobenzene in an amine-P solvent such as N-methylpyrrolidone or dimethylacetamide, or a sulfonic solvent such as sulfolane. A method of reaction is suitable. At this time, in order to adjust the degree of polymerization, it is a preferable method to add an alkali metal salt of carboxylic acid or sulfonic acid or an alkali hydroxide. As a copolymerization component, the copolymerization component may have a nitro, phenyl, or alkoxy group (less than 10 molar ratio), and may have trifunctionality as long as it does not significantly affect the crystallinity of the polymer, but preferably the copolymerization component has a molar width of 5 or less. good. In particular, when a trifunctional or higher functional phenyl, piphenyl, naphthyl sulfide bond, etc. is selected for copolymerization, the molar width is preferably 3 molar width or less, and more preferably 1 molar width or less.

Fibrous reinforcements and other inorganic photonic agents that can be used in the present invention include glass fibers, carbon fibers, calcium titanate, silicon carbide, ceramic fibers, metal fibers, silicon nitride, and barium sulfate.

Calcium sulfate, kaolin, clay, bentonite, sericite, zeolite, silica, mica.

Mica, merk, wollastonite, PMF', 7
Elite, calcium silicate, calcium carbonate, dolomite, antimony trioxide, titanium oxide, iron oxide.

Mild is last, f! There are terrace suits, glass balloons, etc. The amount of these additives may vary from 1 to 9 pps compositions to the PPS composition of the present invention, which may include lubricants such as graphite, molybdenum disulfide, polytetrafluoroethylene, and their stabilizers.

In addition, the PPS composition of the present invention may include an antioxidant, a heat stabilizer, an IP: external radiation absorber, a lubricant, a crystal nucleating agent, a colorant, a silane coupling agent, a silane coupling agent, a No restrictions are imposed by adding a mold release agent.

In addition, the PPS composition of the present invention may contain other thermosetting resins and thermoplastic resins such as epoxy resins, silicone resins, polyimides, polyphenylene ethers, and lyamides, to the extent that they do not impair the object of the present invention.

Polycarbonate, polysulfone, polyethersulfone, polyarylate, polyacetal.

One or more types of polyetherketone, polyetheretherketone, polybutylene terephthalate, polyethylene terephthalate, /lyamideimide, polyetherimide, etc. can be blended. [Example] Next, the present invention will be further explained with reference to Examples. .

Example 1.

Low viscosity PPS resin: V-1 grade (manufactured by Phillips Oil (USA)) 40 parts by weight, glass fiber: C8-03-M
A497 (Asahi fiberglass pear fiber) 20 parts by weight, mica powder varnish light mica 3258
After uniformly mixing 40 parts by weight (manufactured by Marietta Resources, Canada) in a Henschel mixer, the mixture was placed in a 32-inch vented 90x single-screw extruder at a cylinder temperature of 320°C and a screw rotation speed of 120 rpm. supplied. The tip of this extruder is equipped with an underwater cut granulator (manufactured by Nippon Steel Corporation) with 10 nozzles with a hole diameter of φ3 placed on the circumference and a Kuno or Ibu die (manufactured by Nippon Steel). The dice were kept warm. The temperature of the resin discharged from the die surface was 335°C. After the screw of the extruder was stopped, the cutter was brought into contact with the die surface while rotating, and 60° C. hot water was passed into the granulator chamber at the same time as the extruder screw was started.

Screw rotation speed 120 rpm, cutter rotation speed 3GO
In a steady state with a water flow rate of 30,017 min, pellets with an almost spherical shape and no powder or chips were obtained at a rate of 200 to 9/hour.

The pellet was measured with a capillary rheometer under the conditions of 335° C. and a shear rate of about 2×10 21 /see, and found to be 500 poise.

Example 2 In Example 1, PPS: P-4 grade 0 ((
40 parts by weight of Phillips Oil (USA) and 20 parts by weight of V-1 grade, glass fiber: C8-03-MA497
When the composition was adjusted to 40 parts by weight and granulated, pellets of similarly good quality were obtained.

The viscosity measured with a capillary rheometer is 335°C, 1
051/isc conditions, 4 x 10' poise.

Comparative Example 1 In Example 1, a strand die was attached to the tip of the extruder to form the composition into strands, and after cooling on a belt conveyor, the composition was cut into 3 m lengths using a pelletizer, but the resin was brittle. It was impossible to make pellets, and all of the material turned into scraps with powder and cracks.

Comparative Example 2 In Example 1, a core die was used as the die of the underwater cut granulator, but the entire die was closed in 20 seconds after the start of granulation, making underwater granulation impossible.

〔Effect of the invention〕

The present invention can provide a pps composition with a constant shape without chipping or powdering of pellets.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a core die for underwater cutting used when pelletizing resin, and FIG. 2 is a schematic cross-sectional view of a drill die for underwater cutting. FIG. 3 is a schematic cross-sectional view of a pipe die for underwater cutting used in the present invention. The symbols in the figure are as follows. ■・・・Die body■・・・Hardened surface (cutter contact part)■・・・Nozzle

Claims (2)

[Claims] (1) Granular polyphenylene sulfide resin characterized by granulating a resin composition consisting of polyphenylene sulfide resin and a fibrous reinforcing material and/or other inorganic fiber reinforcing material using an underwater cutting granulator equipped with a pipe die. Method of manufacturing the composition. (2) The viscosity characteristics of the resin composition were determined using a capillary rheometer at a temperature of 300 to 380°C and a shear rate of 10^2 to 10^41/sec. 2. The method for producing a granular polyphenylene sulfide resin composition according to claim 1, which has an apparent melt viscosity of less than 10^4 poise under the following conditions.