KR-20260065949-A - Polyamide resin composition and molded body

KR20260065949AKR 20260065949 AKR20260065949 AKR 20260065949AKR-20260065949-A

Abstract

A polyamide resin composition comprising a polyamide resin and a phosphinate compound (C) having a content of 10.0 parts by mass or more and 22.0 parts by mass or less per 100 parts by mass of the polyamide resin, wherein the polyamide resin comprises a polyamide resin (A) having a melting point of 280°C or higher as measured by differential scanning calorimetry (DSC) and an intrinsic viscosity [η] of 0.90 dl/g or higher as measured in 96.5% sulfuric acid at a temperature of 25°C, and a polyamide resin (B) having a melting heat of 0 J/g or more and 5 J/g or less as measured by differential scanning calorimetry (DSC).

Inventors

아마노 아키노리
와시오 이사오
도이 하루카

Assignees

미쯔이가가꾸가부시끼가이샤

Dates

Publication Date: 20260511
Application Date: 20241016
Priority Date: 20231018

Claims (7)

polyamide resin and, It comprises a phosphinate compound (C) having a content of 10.0 parts by mass or more and 22.0 parts by mass or less per 100 parts by mass of the above polyamide resin, and The above polyamide resin is, A polyamide resin (A) comprising a component unit (Aa) derived from a dicarboxylic acid and a component unit (Ab) derived from a diamine, and A polyamide resin (B) comprising a component unit (Ba) derived from a dicarboxylic acid and a component unit (Bb) derived from a diamine, and The above polyamide resin (A) has a melting point of 280°C or higher as measured by differential scanning calorimetry (DSC), and also has an intrinsic viscosity [η] of 0.90 dl/g or higher as measured in 96.5% sulfuric acid at a temperature of 25°C. The above polyamide resin (B) has a melting heat (ΔH) measured by differential scanning calorimetry (DSC) of 0 J/g or more and 5 J/g or less, and The content of the polyamide resin (B) per 100 parts by mass of the polyamide resin is 10.0 parts by mass or more and 40.0 parts by mass or less, and The component unit (Aa) derived from the above dicarboxylic acid and the component unit (Ba) derived from the above dicarboxylic acid both include component units derived from terephthalic acid, and The component unit (Ab) derived from the above diamine and the component unit (Bb) derived from the above diamine both comprise component units derived from 1,6-diaminohexane, Polyamide resin composition.
In claim 1, the polyamide resin (A) is a polyamide resin composition having a melting point of 320°C or lower as measured by differential scanning calorimetry (DSC).
A polyamide resin composition according to claim 1, further comprising a reinforcing material (D) having a content of 30 mass% or more relative to the total mass of the polyamide resin composition.
A polyamide resin composition according to claim 1, wherein the component unit (Ba) derived from the dicarboxylic acid further comprises a component unit derived from isophthalic acid.
A polyamide resin composition according to claim 1, wherein the component unit (Aa) derived from the dicarboxylic acid further comprises a component unit derived from adipic acid.
A polyamide resin composition used to manufacture a molded article having a thick section of 3.5 mm or more in thickness, according to claim 1.
A molded body formed by molding a polyamide resin composition described in any one of claims 1 to 6, and The above-mentioned molded body has a thick section with a thickness of 3.5 mm or more, Molded body.

Description

Polyamide resin composition and molded body The present invention relates to a polyamide resin composition and a molded article. Polyamide resin compositions have been known conventionally as molding materials. Polyamide resin compositions are widely used as materials for various parts, such as automotive parts and electrical and electronic parts, and are known to have excellent mechanical strength of the molded articles. Since polyamide resin compositions are prone to combustion, flame retardancy is required when used, for example, in automotive parts. In this regard, it is known that flame retardancy can be imparted to a molded article by including a flame retardant in the polyamide resin composition. For example, Patent Documents 1 to 7 disclose polyamide resin compositions comprising an aromatic polyamide resin and a flame retardant. It is stated that a molded article exhibits good flame retardancy through the polyamide resin compositions disclosed in Patent Documents 1 to 7. In addition, these polyamide resin compositions include phosphorus-based flame retardants, such as phosphinate compounds, as flame retardants. Embodiments of the present invention will be described in detail below. Furthermore, the present invention is not limited to the following forms. In numerical ranges described stepwise in this disclosure, an upper or lower limit value described in one numerical range may be substituted with an upper or lower limit value of a numerical range described stepwise. Additionally, in numerical ranges described in this disclosure, an upper or lower limit value of said numerical range may be substituted with a value shown in the embodiments. 1. Polyamide resin composition The polyamide resin composition according to the present embodiment comprises a polyamide resin and a phosphinate compound (C) having a content of 10.0 parts by mass or more and 22.0 parts by mass or less per 100 parts by mass of the polyamide resin. The polyamide resin comprises a polyamide resin (A) comprising a component unit (Aa) derived from a dicarboxylic acid and a component unit (Ab) derived from a diamine, and a polyamide resin (B) comprising a component unit (Ba) derived from a dicarboxylic acid and a component unit (Bb) derived from a diamine. The polyamide resin (A) has a melting point of 280°C or higher as measured by differential scanning calorimetry (DSC), and also has an intrinsic viscosity [η] of 0.90 dl/g or higher as measured in 96.5% sulfuric acid at a temperature of 25°C. The above polyamide resin (B) has a melting heat (ΔH) of 0 J/g or more and 5 J/g or less as measured by differential scanning calorimetry (DSC). The content of the above polyamide resin (B) per 100 parts by mass of the above polyamide resin is 10.0 parts by mass or more and 40.0 parts by mass or less. In addition, the component unit (Aa) derived from the above dicarboxylic acid and the component unit (Ba) derived from the above dicarboxylic acid both include component units derived from terephthalic acid, and the component unit (Ab) derived from the above diamine and the component unit (Bb) derived from the above diamine both include component units derived from 1,6-diaminohexane. As described above, when a molded article having a thick section was produced using a polyamide resin composition containing a phosphinate compound as a flame retardant as described in Patent Documents 1 to 7, the tensile strength of the molded article was reduced. The following reasons are considered regarding this. When forming a thick section with a thickness exceeding a certain level, a temperature difference is likely to occur between the outer and inner sides of the thick section during cooling, which can lead to a difference in the timing of curing of the polyamide resin composition between the outer and inner sides of the thick section. Specifically, when the polyamide resin composition melted during molding is cooled and solidified, the polyamide resin composition on the outer side (the part close to the surface of the thick section) cools immediately, while the polyamide resin composition on the inner side (the part far from the surface of the thick section) cools relatively slowly. If the outer side of the thick section cools and hardens first, the uncured inner resin composition is stretched toward the outer side due to the shrinkage that occurs when the outer resin composition hardens. As a result, the inner resin composition that hardens later may harden with air bubbles formed within it, or cracks may occur due to tensile stress. Here, if a phosphinate compound is included in the polyamide resin composition, voids or cracks are particularly likely to occur near the interface between the polyamide resin and the phosphinate compound, making the thick section prone to brittleness. In addition, phosphinate compounds are thermally decomposed by shear heat generated during the mixing of each component constituting the polyamide resin composition, and by heati