JPS5911356A - Heat-resistant resin composition - Google Patents

Abstract

PURPOSE:To provide a resin compsn. having good processability while retaining excellent heat resistance and mechanical properties inherent to polyamide-imide resin, consisting of a polyamide-imide resin and a polyether imide resin in a specified ratio. CONSTITUTION:A resin compsn. consists of 50-99wt% polyamide-imide resin and 1-50wt% polyether imide resin. As the polyamide-imide resin, those having a repeating unit of formula I (wherein Ar is a trivalent arom. group contg. a benzene ring; R is a bivalent org. group) as the main structural unit are preferred. As the polyether imide resin, those having a repeating unit of formula II(wherein R1, R2 are a bivalent org. group) as the main structural unit are preferred. Pref. the amount of the polyether imide resin accounts for 5-30wt% of that of the resin compsn.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heat-resistant resin composition, and its purpose is to improve the processability of polyamide-imide resin.

Polyamide-imide resin exhibits excellent thermal stability because it has a combination of aromatic nuclei and imide bonds, and also exhibits excellent toughness due to flexibility thought to be due to amide bonds. Furthermore, it is an extremely useful engineering plastic because it has excellent chemical resistance and abrasion resistance. However, polyamide-imide resin has a considerably higher melt viscosity than general-purpose thermoplastic resins, and is a material that is difficult to process and mold.

For example, when injection molding is performed, molding must be performed at higher mold and resin temperatures and higher injection pressure than when using ordinary molding materials.

In view of the current situation, the inventors of the present invention have conducted intensive studies to improve the processability of polyamide-imide resins, and have arrived at the present invention.

That is, polyamideimide resin SO~9? It was discovered that a resin composition consisting of a superimposed part and a polyetherimide resin/~SO weight part has excellent heat resistance and mechanical properties of a polyamideimide resin, and also has good processing and moldability. It has arrived.

The present invention will be explained in more detail below.

The polyamide-imide resin used in the present invention is already commercially available, and is a synthetic resin having imide and amide bonds in the repeating unit of the main chain.

Preferably, a polyamideimide having as a main structural unit a repeating unit represented by the following formula (wherein Ar is a trivalent aromatic group containing at least one benzene ring, and R is a covalent organic group) resin is used.

Examples of the lf group include aromatic groups and aliphatic groups.

For example, it is a polyamideimide resin obtained by the reaction of trimellitic acid and ri'-diaminodiphenyl ether.

In the present invention, polyetherimide resins are melt blended to improve processability. The polyamide-imide resin used in the present invention is a synthetic resin with imide and ether bonds in the repeating units of the main chain, and has a strong affinity for polyamide-imide resins.
It can be uniformly dispersed in polyamideimide resin.

Preferably, a polyetherimide resin having a repeating unit represented by the following formula (wherein R, , R represents a covalent organic group) as a main structural unit is used.

For example, 2. -′-bis[gu(u,3-dicarboxyphenoxy)phenyl]propanedic anhydride, λ′
- The product obtained by the reaction of an aromatic bis(ether acid anhydride) such as bis[gu(3,II-dicarboxyphenoxy)phenyl]furopansic anhydride with m-phenylenediamine is a repeating compound represented by the following formula: It is a polyetherimide resin having units. Preferably, those having a polymerization degree of S-200 are used.

The proportion of the polyether 5-imide resin in the resin composition of the present invention is suitably within the range of 0 to 10%. The effect of improving the processability of polyetherimide resin can be seen even when a relatively small amount is added, but it is preferably S weight or more. Since the mechanical strength of polyetherimide resin is inferior to that of polyamideimide resin, there is an upper limit to the content of polyetherimide resin in the resin composition, and the content of polyetherimide resin in the resin composition is suitably less than SO. Preferably, the amount is 30% by weight or less.

The method of mixing and preparing the resin composition of the present invention is not particularly limited, but an apparatus used for melt-blending common plastics may be used.

For example, a hot roll, a Banbury mixer, a plan bender, an extruder, etc.

Melt blending is continued until a uniform resin composition is obtained, and the mixing temperature is set above a temperature at which both components can be melted and below a temperature at which both components undergo thermal decomposition. Preferably 3
It is selected from the range of θO°C to 3gθ°C.

-6= When mixing and preparing the resin composition of the present invention, the polyamideimide resin and the polyetherimide resin can be premixed in advance using various blenders and then fed to the melt mixer. Even if the resin composition is supplied to a mixer, it is sufficient if a uniform resin composition can be obtained.

In addition, when producing molded products of the resin composition of the present invention using a molding machine with high melt-mixing capacity, it is not necessarily necessary to prepare a uniform resin composition in advance; It is also possible to supply a resin, a polyetherimide resin, or a tri-blend thereof directly to a molding machine to produce a uniform molded product.

As a molding method for the resin composition of the present invention, injection molding shows high productivity, but other molding methods such as compression molding, extrusion molding, sintering molding, etc. can also be applied, and there is no problem.

The resin composition of the present invention has excellent heat resistance and mechanical properties, and has improved processing and moldability, so it is extremely useful as a high-performance plastic in many applications. For example, it is extremely useful for office machine parts such as copying machines and computer terminals, electrical and electronic parts, automobile parts, and special machine parts such as bearing holders.

Next, the present invention will be explained in more detail with reference to examples, but the present invention is not limited to the following examples as far as the gist of the present invention goes beyond.

Examples / - D and Comparative Example 7 - Polyamide-imide resin molding material Torlon 1I2oar, ()-ron is a trademark of Amoco Corporation in the United States) whose repeating structural unit is represented by the following formula.
and Ultem 1ooo (Ultem is a trademark of General Electric Company, USA) whose repeating structural unit has the following formula were used as raw materials for the heat-resistant resin composition of the present invention.

(1) After tri-blending melt viscosity token 11.203 L and Ultem 1000 with each composition shown in the table, a single screw extruder (screw diameter = 2, I, /D: /za, compression ratio j /, F, /4rel temperature = 35θ°C, screw rotation speed: 10θr, p, m, ) and melt-kneaded to obtain uniform pellets.

The melt viscosity of Konohelet was measured using a Koka type flow tester.

The measurement temperature was 3sq℃, and the dice used were: LgXgL
Dressed in silk. The melt viscosity of each composition at a shear rate of -/005ec-' is shown in Table-/.

(11) After tri-blending comb-shaped flow length token II; 103 L and Ultem 1000 with each composition shown in the table, an injection molding machine (manufactured by West German Aburg Co., Ltd., Aburg All Laung A Near 01 barrel temperature = 330 ° C. , -〇 - Mold temperature +2.10℃, injection pressure; roughness kg/at
/l), and the flow length of the cross section of jXO, Atmm was measured. The results are shown in Table-/.

(Il+) Display physical property token '7203 L and Ultem 1000 of molded product.
After tri-blending with each composition shown in /, molded test pieces (, ?tX/, ?X/30IIL
j+) was produced. The molded test pieces having the compositions of Examples/~y and Comparative Example// were heat treated in air at 763°C, -5°C, and 0°C for a period of time at each temperature. Since the molded test piece having the composition of Comparative Example deforms when heat treated under the above conditions, the physical properties were measured without heat treatment.

The measurement items were bending strength, isot impact strength with cutting notches, and heat deformation temperature, and the measurement methods were in accordance with A8TM.

The results are summarized in Table 1 and show that Examples 1 to 2 had extremely well-balanced physical properties.

-10-

Claims (3)

[Claims] (1) Polyamideimide resin jθ~9? % by weight and a resin composition consisting of 7 to 50% by weight of polyetherimide resin (2) The polyamideimide resin has the following formula (in the formula Ar
is a trivalent aromatic group containing at least seven benzene rings,
The resin composition according to claim 1, which is a polyamide-imide resin having a repeating unit represented by (R represents a divalent organic group) as a main structural unit. (3) The polyetherimide resin has the following formula (in the formula R, ,
3. The resin composition according to claim 1, which is a polyetherimide resin having as a main structural unit a repeating unit represented by (R, represents a covalent organic group).