JPH08208883A - New additive for molding thermoplastic resin - Google Patents

Abstract

PURPOSE: To provide a new additive containing an aromatic carboxylic acid having amino group directly bonded to the aromatic ring as an active component and enabling the molding of a thermoplastic resin under low temperature and pressure condition without lowering the mechanical properties, thermal properties and molecular weight of the molded product. CONSTITUTION: This new additive for the molding of a thermoplastic resin enabling the thermal molding of a thermoplastic resin (e.g. polybutylene terephthalate) at decreased temperature under decreased pressure without lowering the mechanical properties, thermal properties and molecular weight of the molded article is produced by using, as an active component, an amino group- containing aromatic carboxylic acid such as anthranilic acid, 3-aminobenzoic acid and 4-aminobenzoic acid as an aromatic carboxylic acid having amino group directly bonded to the aromatic ring.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a molding processing additive for thermoplastics containing an amino group-containing aromatic carboxylic acid as an active ingredient, and a thermoplastic composition containing the additive.

[0002]

2. Description of the Related Art Conventionally, as a processing additive for thermoplastics, for example, esters of monoglycerin, higher fatty alcohols, higher fatty acids, metal soaps, bisamides and the like are known. However, it is desired to develop a new molding additive which has excellent properties as a molding additive and is easily available.

[0003]

Under the background of the prior art described in the preceding paragraph, the object of the present invention is to newly develop a molding processing additive having excellent characteristics as a molding processing additive and easily available, Is to provide.

[0004]

Means for Solving the Problems As a result of repeated studies on the above problems, the present inventors have found that an aromatic carboxylic acid having an amino group directly bonded to an aromatic ring is used as a molding additive for thermoplastics. The inventors have found that they have excellent characteristics and completed the present invention.

That is, the present invention provides: (1) a thermoplastic molding additive characterized by containing an amino group-containing aromatic carboxylic acid as an active ingredient; and (2) such a molding additive to a thermoplastic. The present invention relates to a thermoplastic composition characterized by containing an agent.

The present invention will be sequentially described below.

The amino group-containing aromatic carboxylic acid, which is an active ingredient of the thermoplastic processing additive of the present invention, is an aromatic compound having an amino group and a carboxyl group such as anthranilic acid, 3-aminobenzoic acid and 4-aminobenzoic acid. It is a family compound.

The plastics in which such a molding processing additive is to be used are the thermoplastics among the so-called engineering plastics. Among them, the thermoplastics having a relatively high melting point are the moldings of the present invention. The effect of using the additive is remarkable. Examples of such thermoplastics include polyamide resins, polycarbonate resins, polyester resins and the like.

Due to their excellent mechanical strength and heat resistance, these engineering plastics have been attracting attention as structural and mechanical member materials that can replace metals. It is particularly lightweight and chemically stable, so it is used in the field of automobiles, and because of its excellent electrical insulation and dimensional stability, it is used in the fields of electricity and electronics and precision machinery, and its application range is wide. For these reasons, the engineering plastics market is expanding year by year, and further expansion is expected.

In the molding of thermoplastics, it is generally desirable that molding can be carried out at a lower temperature, but this is especially true for those having a relatively high melting point. Polyamide resins and polyester resins generally have higher melting points than other engineering plastics, but when molding such high melting point thermoplastics, extrusion molding machines, injection molding machines, etc. It is necessary to set the temperature of the cylinder and the like of the molding machine of No. 2 to be high, and it is necessary to use a molding machine having a large heating capacity, and there is a problem in terms of cost.

The situation regarding polycarbonate is as follows. Polycarbonate has a high melting point (220-
Since the temperature is 230 ° C., the molding temperature is as high as 240 to 300 ° C. In addition, the molding temperature is the decomposition temperature (about 320
However, if it is exposed to heat for a long time, it may cause thermal deterioration. Furthermore, the melt viscosity is extremely high, and there is a drawback that the flow in the mold is poor during injection molding. Further, there is a problem in terms of cost because a high temperature is required at the time of molding.

According to the findings of the present invention, a polyamide resin,
When a small amount of molding additive is added to thermoplastic such as polyester resin and extrusion molding or injection molding is performed, the resin pressure at the time of molding is lowered and the melt viscosity is lowered. It became possible to perform molding at temperature. In the case of polycarbonate, in addition to these, the molded product shows almost no change in mechanical strength and thermal properties (melting point), so extrusion molding or injection molding can be performed at a lower molten resin temperature. The flow (fluidity) in the mold at a certain time is improved, it is not necessary to use a molding machine having a large heating capacity, and this leads to cost reduction.

The blending amount of the amino group-containing aromatic carboxylic acid, which is a molding processing additive of the present invention, in the thermoplastic is basically the above-mentioned use effect, that is, the resin pressure during molding and the melt viscosity decrease. There is no particular limit other than the amount produced. From this point of view, the amount of the amino group-containing aromatic carboxylic acid used is usually in the range of 0.01 to 5 phr based on the thermoplastic. If the amount used is too small, the effect of use does not occur. On the other hand, if the amount used exceeds this range, not only the use effect does not increase, but also the strength of the molded product may decrease.

There is also no particular limitation on the thermoplastic composition in which the molding additive of the present invention is blended with the thermoplastic. Even when such a composition is in the form of a mixture of an amino group-containing aromatic carboxylic acid and a thermoplastic resin such as pellets or powder, the amino group-containing aromatic carboxylic acid is kneaded into the thermoplastic resin. It may be in a convenient form such as a pellet or powder.

No particular limitation is imposed on the thermoplastic resin which is blended with the amino group-containing aromatic carboxylic acid and subjected to heat molding by extrusion molding, injection molding or the like, and the total amount of the amino group-containing aromatic carboxylic acid used. Is usually in the range of 0.01 to 5 phr mentioned above.

The molded product thus obtained does not show any deterioration in its mechanical properties and thermal properties such as melting point as compared with the molded product obtained without using the molding additive.

[0017]

EXAMPLES The present invention will be further described below with reference to examples.

EXAMPLE 1 0.5 p of dried anthranilic acid was added to polybutylene terephthalate (PBT) dried under reduced pressure at 70 ° C. for 5 hours.
After blending for hr, a film-shaped extruded product was produced by an extrusion molding machine (“TYPE2024UF4P” manufactured by Daiei Engineering Co., Ltd.). The heating temperature of the extruder was 230, 240, 250 and 250 ° C. from the hopper side, and the screw rotation speed was 10 rpm.

The resin pressure during extrusion molding is shown in Table 1.

As the physical properties of the extruded product, melt viscosity, intrinsic viscosity, tensile strength and melting point of the extruded product were measured. The melt viscosity was measured using a capillary rheometer (“CFT-500C” manufactured by Shimadzu Corporation) at 250 ° C. and a load of 10 k.
gf / cm ² , die diameter 1 mm, die length 10 mm
It was measured at. The limiting viscosity was measured by using an Ostwald viscometer and dissolving the molded product in a phenol-tetrachloroethane 40/60 mixed solvent at 30 ° C. Tensile strength is Shimadzu Corporation Autograph S100 type, and the tensile speed is 5
It was measured at cm / min and a temperature of 25 ° C.

Table 2 shows the melt viscosity, intrinsic viscosity, tensile strength and melting point of the extruded product.

EFFECTS OF THE INVENTION By adding an amino group-containing aromatic carboxylic acid as a molding processing additive during thermoforming of thermoplastics, it becomes possible to set the cylinder temperature of the molding machine at a low temperature because of the decrease in melt viscosity. However,
Can be extruded or injection molded at lower molten resin temperatures,
Therefore, it is no longer necessary to use a molding machine with a large heating capacity. And this also leads to cost reduction. In addition, the molded product does not show deterioration in mechanical and thermal properties and molecular weight. Reference number 1995-1 A written statement that describes the chemical formula, etc.

[Table 1]

[Table 2]

Claims (1)

[Claims] 1. A heat comprising a processing additive containing an aromatic carboxylic acid having an amino group directly bonded to an aromatic ring (hereinafter abbreviated as an amino group-containing aromatic carboxylic acid) as an active ingredient. Plastic composition.