JPS6015452A - Polyether ketone resin composition - Google Patents

Abstract

PURPOSE:To provide the titled compsn. having excellent hot water resistance, mechanical strength and low shrinkage, consisting of a polyether ketone and a specified inorg. filler. CONSTITUTION:30-95wt% polyether ketone having an intrinsic viscosity of 0.3- 2.6 is mixed with 70-5wt% inorg. filler contg. at least 40wt% powdered, acicular, fibrous or scaly alumina or zirconia having a particle size of 20mu or below, or a fiber diameter of <=20mu and a fiber length of <=3mm..

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyetherketone resin composition having good hot water resistance, low shrinkage, and high mechanical strength.

Polyetherketone resins are attracting attention as edge-wearing plastics with excellent heat resistance, hot water resistance, flammability, and chemical resistance in a wide range of application fields such as electricity, electronics, automobiles, aircraft, and nuclear power fields.

However, since this resin is a crystalline resin, it has a characteristic that it shrinks when solidifying from a molten state, that is, it has a large molding shrinkage rate. In addition, because the crystallization rate is slow, the maximum crystallinity is not reached immediately after molding, and the crystallinity gradually increases under high temperatures or in hot water, steam atmosphere, etc.
As a result, contraction progresses. In particular, this resin has excellent hot water and steam resistance that does not cause chemical deterioration even under hot water of 200°C or higher and steam, so it is especially suitable for nuclear power, crude oil mining, and chemical equipment that require severe hot water resistance conditions. However, due to the large molding shrinkage and post-shrinkage mentioned above, it is expected to be applied to parts that require precise dimensional accuracy, and metal parts. - Its application has been limited in combination with low-shrinkage materials such as hemlock, bonding, coating, etc.

In general, methods for reducing molding shrinkage and post-recovery are as follows:
Fibrous reinforcement materials such as glass fiber, powdered and acicular materials such as talc, calcium carbonate, magnesium carbonate, calcium sulfite, aluminum hydroxide, mica, molybdenum disulfide, wollastonite, graphite, titanium white, and glass beads. Alternatively, it is known that it is effective to blend a flaky inorganic filler or the like into the resin.

Even in polyetherketone resin, when the above-mentioned reinforcing materials and fillers are blended, the molding shrinkage rate and
Although the post-shrinkage rate is reduced, the mechanical strength is low and the hot water resistance, which is an excellent property of this resin, is significantly reduced, so its use in severe hot water and steam atmospheres is restricted. Is receiving.

In many application fields, it is strongly required that the resin maintain good hot water resistance, improve molding shrinkage rate and post-shrinkage rate, and have high mechanical strength.

In view of the above circumstances, the present inventor has conducted extensive research and found that it is possible to obtain a composition that satisfies the above requirements by incorporating an inorganic filler containing alumina or zirconia as a main component into polyetherketone. They discovered this and arrived at the present invention.

The present invention uses an inorganic filler 70 containing 80 to 95 wt% of polyetherketone and alumina or zirconia as main components.
This is a polyetherketone resin composition having a characteristic that it consists of ~5 wt%.

The polyether ketone used in the present invention contains repeating units alone or together with other repeating units, and has an intrinsic viscosity of preferably 0.3 to 2.6, more preferably 0.5 to 1.8. preferable.

Other repeating units may include less than 25% vt% of pe>30□(Ge〇-), but polymers containing 25 wt% or more are not preferable because the above-mentioned properties of the polyetherketone are lost. Once refers to the intrinsic viscosity measured at 25°C for a solution of the polymer in concentrated sulfuric acid having a density of 1.84 F/4 containing 0.11 polymer per 100 mm of solution.

The intrinsic viscosity was measured using a viscometer with a solvent flow time of about 2 minutes. This intrinsic viscosity is a value that uniquely corresponds to the molecular weight of the polymer.

The intrinsic viscosity of the polyetherketone according to the present invention is 0.8
It is preferably from 2.6 to 2.6, more preferably from 0.5 to 1.8. However, if the intrinsic viscosity is less than 0.8, the heat resistance and hot water resistance are low due to the low molecular weight, and the alumina or zirconia is brittle. Even by blending an inorganic filler containing as a main component, a composition having sufficient strength and hot water resistance cannot be obtained. If the intrinsic viscosity exceeds 2.6, the melt viscosity is high, resulting in insufficient fluidity during melt molding, making it impossible to obtain a good molded product. It is preferable that the intrinsic viscosity is in the range of 0.8 to 2.6 because it provides good surface appearance and excellent physical properties and processability.

The polyetherketone can be obtained by the method disclosed in JP-A-54-90296.

Na (Al120*) or zit record = 7 (Z
It is an inorganic substance containing 40% or more, preferably 50% or more of r02). 40% alumina or zirconia
When an inorganic substance containing the following is blended into polyether-reketone, it exhibits good hot water resistance and steam resistance, but when the inorganic substance contains 50% or more of alumina or zirconia, it exhibits even higher hot water resistance. , which exhibits steam resistance and is preferred.

The shape of the inorganic filler is not particularly limited. Powder-like, needle-like, fibrous, or scale-like shapes are applicable, but particles with a particle size of 20μ or less, or 20μ
Those having the following fiber diameters and fiber lengths of 8 or less are preferable from the viewpoint of dispersibility and workability. Even if long fibers, rovings, or yarns with a length of 35 or more are used, 35
Similar excellent properties can be obtained by obtaining a uniform dispersion state with a fiber length of 131 or less.

The inorganic filler can normally be used without treatment, but in order to have an affinity with polyetherketone, a silane coupling agent such as aminosilane or epoxysilane, chromic chloride, or other surface treatment agent depending on the purpose is used. can do.

The amount of inorganic filler containing alumina or zirconia as a main component to be blended into polyetherketone is 3% to 95V1t% of polyetherketone, 70% of the inorganic filler, based on the total amount of polyetherketone and the inorganic filler. ~5 wL
% is appropriate, and if the polyetherketone exceeds 95 wL% and the filler is less than 5 wt%, the desired improvement in molding shrinkage and post-shrinkage will be insufficient; less than Q wt%, the filler is 7QwL
%, the dispersion in the melt mixer is insufficient and the melt viscosity increases significantly, resulting in low fluidity.
Molding under normal conditions becomes difficult, which is not preferable.

The means of blending the composition of the present invention is not particularly limited. It is possible to feed polyetherketone and the filler separately to a melt mixer, or these raw materials are premixed in a mortar, Henschel mixer, ball mill, ribbon blender, etc. and then melt mixed. It can also be supplied to machines.

The composition of the present invention may contain antioxidants, heat stabilizers, ultraviolet absorbers, lubricants, mold release agents, colorants such as dyes and pigments, flame retardants, One or more conventional additives such as flame retardant aids and antistatic agents can be added.

The present invention will be described below with reference to Examples, but these are merely illustrative and the present invention is not limited thereto.

Examples 1 to 8 Polyetherketone having an intrinsic viscosity of 0.8, alumina fiber manufactured by IC1, Saf 4 (Ad203.9)
5%;
After melt-kneading at a temperature of 860°C, the strands are water-cooled,
Pellets were obtained by cutting.

The obtained pellets were injection molded (Sumitomo-Nestal 47/
28 injection molding machine, cylinder temperature 370℃, mold temperature 1
60°C) to obtain a bent test piece.

Using a bending test piece, the bending strength, breaking strain, and molding shrinkage rate were measured, and the shrinkage rate, bending strength, and breaking strain after being immersed in hot water at 1.250°C for 500 hours were also measured.

The bending strength was measured according to AS'rM D-790.

Comparative Example 1-2 Polyetherketone and aluminum fM used in Examples 1 to 3
& fibers were mixed in the proportions shown in Table 1, processed in the same manner as in Examples 1 to 3, and measured for physical properties.

Comparison Example 8 The polyetherketone and glass fiber used in Examples 1 to 8 (Asahi Fiberglass C5Q 3-MA497, Si
O252-56%, A1120812-16%,
ZrO□0%) was mixed in the proportions shown in Table 1, processed in the same manner as in Examples 1 to 3, and measured for physical properties.

Comparative Examples 4 to 5 Polyetherketone and wollastonite used in Examples 1 to 3 (NYAD-G manufactured by Chomen Sangyo, Ca Siol
, acicular), amorphous silica (Denki Kagaku L-44, 5in
2. Spherical) They were mixed in the proportions shown in Table 1, processed in the same manner as in Examples 1 to 3, and measured for physical properties.

Examples 4 to 5 Polyetherketone and zirconia used in Examples 1 to 3 (5OPTZ r02 99.6% manufactured by Rare Genso Kagaku Co., Ltd.)
) and alumina-silica fiber (Isolite Industrial Co., Ltd., 147% A420, 252% 5i0) were mixed in the proportions shown in Table 1, processed in the same manner as in Examples 1 to 3, and measured for physical properties.

As seen in the results in Table 1, 70 to 5 wL of filler containing 40W% or more of alumina or zirconia was used.
% (Examples 1 to 5) have low molding shrinkage and shrinkage after hot water immersion, high dimensional wheat productivity, high strength, and high strength retention even after severe hot water treatment. I understand.

On the other hand, polyetherketone alone (Comparative Example 1) has a high strength retention rate after hot water treatment, but also has a large shrinkage after molding convergence and water treatment, and has poor dimensional stability.

In addition, systems containing fillers other than the compositions of the present invention (Comparative Examples 3 and 4) had good dimensional stability, but the strength decreased significantly after hot water treatment, and they were resistant to severe hot water conditions. It turns out that there isn't.

Claims (1)

[Claims] A polyetherketone resin composition containing 80-95 wt% of polyetherketone.