KR-20260067359-A - Method for preparing pellet blends, masterbatches, and resin compositions

Abstract

A pellet blend, a masterbatch using the pellet blend, and a method for manufacturing a resin composition are provided. The pellet blend comprises a masterbatch (1) containing 0.5 to 3.0 parts by mass of a formaldehyde catcher (B) per 100 parts by mass of a polyacetal resin (A) having a melt volume rate (MVR) of 5 to 50 cm³/10 min measured at 190°C and a load of 2.16 kg in accordance with ISO1133, and a pellet (2) containing a polyacetal resin (C) having a melt volume rate (MVR) of 0.1 to 4 cm³/10 min or less measured at 190°C and a load of 2.16 kg in accordance with ISO1133.

Inventors

• 스나가 다이스케
• 후쿠하라 가린
• 고바야시 다이스케

Assignees

• 글로벌 폴리아세탈 가부시키가이샤

Dates

Publication Date

20260512

Application Date

20240903

Priority Date

20230912

Claims (6)

1. A master batch (1) comprising 0.5 to 3.0 parts by mass of a formaldehyde capture agent (B) per 100 parts by mass of a polyacetal resin (A) having a melt volume rate (MVR) of 5 to 50 cm³/10 min measured under conditions of 190°C and a load of 2.16 kg in accordance with ISO1133, and A pellet (2) comprising a polyacetal resin (C) having a melt volume rate (MVR) of 0.1 to 4 cm³/10 min or less, measured under conditions of 190°C and a load of 2.16 kg in accordance with ISO1133, Pellet blend.
2. In Article 1, A pellet blend comprising 3 to 25 parts by mass of master batch (1) for every 100 parts by mass of the above pellet (2).
3. In Article 1 or Article 2, The above formaldehyde scavenger (B) is a pellet blend comprising at least one selected from the group consisting of hydrazide compounds, hydrazone bodies of hydrazine compounds, guanamin compounds, and urea compounds.
4. A master batch comprising 0.5 to 3.0 parts by mass of a formaldehyde capture agent (B) per 100 parts by mass of a polyacetal resin (A) having a melt volume rate (MVR) of 5 to 50 cm³/10 min measured under conditions of 190°C and a load of 2.16 kg in accordance with ISO1133.
5. In Article 4, The above formaldehyde scavenger (B) comprises at least one selected from the group consisting of hydrazide compounds, hydrazone bodies of hydrazine compounds, guanamine compounds, and urea compounds, in a master batch.
6. The method comprises melt-kneading a polyacetal resin (C) and a masterbatch (1), wherein the melt volume rate (MVR) measured under conditions of 190°C and a load of 2.16 kg is 0.1 to 4 cm³/10 min or less in accordance with ISO1133. A method for preparing a resin composition comprising 0.5 to 3.0 parts by mass of a formaldehyde capture agent (B) to 100 parts by mass of a polyacetal resin (A) having a melt volume rate (MVR) of 5 to 50 cm³/10 min measured under conditions of 190°C and a load of 2.16 kg in accordance with ISO1133.

Description

Method for preparing pellet blends, masterbatches, and resin compositions The present invention relates to a method for manufacturing a pellet blend, a masterbatch, and a resin composition. Polyacetal resin has high mechanical strength and stiffness, excellent oil resistance and resistance to organic solvents, and is a well-balanced resin over a wide temperature range, and is also easy to process. Therefore, polyacetal resin is a representative engineering plastic and is widely used in OA equipment, digital home appliances, automotive parts, and other industrial parts. However, since polyacetal resins are prone to generating formaldehyde, a formaldehyde scavenger is incorporated into the polyacetal resin (Patent Document 1, Patent Document 2). Hereinafter, a form for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. Furthermore, the following present embodiment is an example for explaining the present invention, and the present invention is not limited to the present embodiment. Additionally, in this specification, "∼" is used to mean including the numerical values described before and after it as lower and upper limits. In this specification, various physical properties and characteristic values are defined as being at 23°C unless specifically described otherwise. In cases where measurement methods, etc. described by the standards in this specification differ from year to year, unless specifically stated otherwise, they shall be based on the standards as of January 1, 2023. The pellet blend of the present embodiment is characterized by comprising a master batch (1) comprising 0.5 to 3.0 parts by mass of a formaldehyde catcher (B) per 100 parts by mass of a polyacetal resin (A) having a melt volume rate (MVR) of 5 to 50 cm³/10 min measured at 190°C and a load of 2.16 kg in accordance with ISO1133, and a pellet (2) comprising a polyacetal resin (C) having a melt volume rate (MVR) of 0.1 to 4 cm³/10 min or less measured at 190°C and a load of 2.16 kg in accordance with ISO1133. By configuring it in this way, a pellet blend containing a high-viscosity polyacetal resin and a formaldehyde capture agent is obtained, which has a high formaldehyde capture effect and is also less likely to cause mold contamination. Conventionally, when a formaldehyde capture agent was blended with polyacetal resin, both were compounded directly in an extruder. During compounding, the extruder's set temperature for the polyacetal resin is typically set to around 200°C; however, it was found that even when high-viscosity polyacetal resin is melt-blended at around 200°C, shear heat generation within the extruder becomes significant, causing the resin temperature to rise considerably higher than the extruder's set temperature. Consequently, as the resin temperature rises in this manner, a large amount of the formaldehyde capture agent is consumed within the extruder. Under these circumstances, in the present embodiment, a formaldehyde capture agent (B) is first blended into a polyacetal resin (A) having an MVR of 5 to 50 cm³/10 min, melt-kneaded to form a master batch, and then blended with pellets of a polyacetal resin (C) having an MVR of 0.1 to 4 cm³/10 min or less. By adopting this method, the formaldehyde capture agent (B) can be blended into the polyacetal resin without excessive shear heat generation during compounding (pellet production). As a result, it was found that the heating process related to the formaldehyde capture agent (B) can be performed only during molding, thereby avoiding unnecessary consumption of the formaldehyde capture agent (B). As a result, despite using a high-viscosity polyacetal resin and incorporating a formaldehyde capture agent, a pellet blend was obtained in which the formaldehyde capture effect of the resulting molded product was sufficiently high and mold contamination was suppressed. The details of the present embodiment will be described below. <Master Batch (1)> The master batch (1) of the present embodiment comprises 0.5 to 3.0 parts by mass of a formaldehyde capture agent (B) with respect to 100 parts by mass of a polyacetal resin (A) having a melt volume rate (MVR) of 5 to 50 cm³/10 min measured under conditions of 190°C and a load of 2.16 kg in accordance with ISO1133. In this master batch (1), since excessive shear heat is not generated during the melt mixing for master batch formation, the consumption of formaldehyde capture agent (B) during melt mixing can be minimized. <<Polyacetal Resin (A)>> Masterbatch (1) comprises a polyacetal resin (A) having a melt volume rate (MVR) of 5 to 50 cm³/10 min measured under conditions of 190°C and a load of 2.16 kg in accordance with ISO1133. The melt volume rate (MVR) of the polyacetal resin (A), measured in accordance with ISO 1133 under conditions of 190°C and a load of 2.16 kg, is preferably 7 cm³/10 min or more, more preferably 10 cm³/10 min or more, even more preferably 15