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KR-20260067882-A - POLYOXYMETHYLENE RESIN COMPOSITION AND MOLDED ARTICLE PREPARED THEREFROM

KR20260067882AKR 20260067882 AKR20260067882 AKR 20260067882AKR-20260067882-A

Abstract

One embodiment provides a polyoxymethylene resin composition comprising a polyoxymethylene resin, a dihydrazide compound, and a urea compound, wherein the weight ratio of the dihydrazide compound to the urea compound is 1:3 to 1:5.

Inventors

  • 정진형

Assignees

  • 코오롱이앤피 주식회사

Dates

Publication Date
20260513
Application Date
20241106

Claims (14)

  1. It includes polyoxymethylene resin, dihydrazide compounds, and urea compounds, A polyoxymethylene resin composition having a weight ratio of the dihydrazide compound and the urea compound of 1:3 to 1:5.
  2. In paragraph 1, A polyoxymethylene resin composition comprising 95% to 99.8% by weight of the polyoxymethylene resin with respect to 100% by weight of the polyoxymethylene resin composition.
  3. In paragraph 1, A polyoxymethylene resin composition having a melting point of 160°C to 180°C for the polyoxymethylene resin.
  4. In paragraph 1, A polyoxymethylene resin composition comprising 0.01% to 1% by weight of the dihydrazide compound relative to 100% by weight of the polyoxymethylene resin composition.
  5. In paragraph 1, A polyoxymethylene resin composition comprising the above dihydrazide compound adipic acid dihydrazide, sebacic acid dihydrazide, isophthalic acid dihydrazide, dodecanedioic dihydrazide, 1,12-dodecanedicarboxylic acid dihydrazide, or a combination thereof.
  6. In paragraph 1, A polyoxymethylene resin composition comprising 0.01% to 1% by weight of the urea compound relative to 100% by weight of the polyoxymethylene resin composition.
  7. In paragraph 1, A polyoxymethylene resin composition comprising the above urea compound, ethylene urea, (2,5-dioxo-4-imidazolidinyl)urea, or a combination thereof.
  8. In paragraph 1, The above polyoxymethylene resin composition further comprises a metal salt phosphate-based compound.
  9. In paragraph 8, A polyoxymethylene resin composition in which the metal salt phosphate-based compound is an ester-based compound containing a metal salt comprising Mg, Ca, Zn, Ba, Fe, or a combination thereof.
  10. In paragraph 8, A polyoxymethylene resin composition comprising 0.01% to 1% by weight of the metal salt phosphate-based compound with respect to 100% by weight of the polyoxymethylene resin composition.
  11. In paragraph 1, The above polyoxymethylene resin composition further comprises a hindered phenolic antioxidant.
  12. In Paragraph 11, A polyoxymethylene resin composition comprising 0.01% to 0.5% by weight of the hindered phenolic antioxidant based on 100% by weight of the polyoxymethylene resin composition.
  13. A molded article manufactured from a polyoxymethylene resin composition according to any one of claims 1 to 12.
  14. In Paragraph 13, The above-mentioned molded article is a molded article having a formaldehyde gas emission of 2 mg/kg or less at 200 ℃ according to VDA-275 standards.

Description

Polyoxymethylene resin composition and molded article prepared therefrom The present disclosure relates to a polyoxymethylene resin composition and a molded article made therefrom. Polyoxymethylene resin is widely used in various fields as an engineering resin with excellent physical properties, such as mechanical and electrical characteristics, and chemical properties, such as chemical resistance and heat resistance. However, as the application range of polyoxymethylene resins expands, it is required that the polyoxymethylene resins possess more specialized properties. Conventionally, when manufacturing molded products by injection molding polyoxymethylene resin, there was a problem in which the resin decomposed, forming deposits such as mold deposits on the surface of the mold cavity. In particular, when the polyoxymethylene resin contains additives to reduce formaldehyde emissions, the occurrence of such deposits increases further, which caused defects in molded products using polyoxymethylene resin. Figure 1 is a photograph showing an injection molded product with a deposit amount of '1' (none). Figure 2 is a photograph showing an injection molded product with a deposit amount of '10' (severe). The advantages and features of the technology described below, and the methods for achieving them, will become clear by referring to the embodiments described in detail below. However, the forms of implementation are not limited to the embodiments disclosed below. Unless otherwise defined, all terms used in this specification (including technical and scientific terms) may be used in a meaning that is commonly understood by those skilled in the art. Furthermore, terms defined in commonly used dictionaries are not to be interpreted ideally or excessively unless explicitly and specifically defined otherwise. Throughout this specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components. Furthermore, the singular form includes the plural form unless specifically stated otherwise in the text. A polyoxymethylene resin composition according to one embodiment comprises a polyoxymethylene resin, a dihydrazide compound, and a urea compound, wherein the weight ratio of the dihydrazide compound to the urea compound is 1:3 to 1:5. A polyoxymethylene resin composition according to one embodiment includes a dihydrazide compound and a urea compound, which are additives for reducing formaldehyde, in an optimal weight ratio, thereby maintaining the formaldehyde gas emission control performance while preventing deposition or significantly improving the degree of deposition even under harsh injection molding conditions. Polyoxymethylene resin Polyoxymethylene resin serves as the base resin of the resin composition, playing a role in securing the basic mechanical and chemical properties of the resin, and performing a particularly important function in impact resistance. Polyoxymethylene can be used without particular limitation as long as it is a standard polyoxymethylene commercially available. Polyoxymethylene may be an oxymethylene homopolymer in which both ends are blocked by ester or ether groups, containing oxymethylene -(OCH 2 ) n - groups as repeating units, or an oxymethylene copolymer in which oxyalkylene units having 2 to 8 carbon atoms are randomly inserted into a polymer main chain composed of oxymethylene monomer units, and both ends of the polymer are blocked by ester or ether groups, or a terpolymer. For example, oxymethylene homopolymers and oxymethylene copolymers can be prepared by the following method. First, oxymethylene homopolymers can be prepared by introducing formaldehyde anhydride into an organic solvent containing a basic polymerization catalyst, such as, for example, an organic amine, an organic or inorganic tin compound, or a metal hydroxide, polymerizing the polymer, filtering the polymer, and then heating the ends in acetic anhydride in the presence of sodium acetate to acetylate them. In addition, oxymethylene copolymers can be prepared by dissolving or suspending a cyclic oligomer of formaldehyde, such as trioxane anhydride or tetraoxane, and a cyclic ether, such as ethylene oxide, propylene oxide, 1,3-dioxolane, 1,3-propanedioformal, 1,4-butanediolformal, 1,5-pentanediolformal, 1,6-hexanediolformal, diethylene glycolformal, 1,3,5-trioxepane, or 1,3,6-trioxocane, in an organic solvent such as cyclohexane or benzene, then adding a Lewis acid catalyst such as boron trifluoride diethyl etherate to polymerize and decomposing the unstable ends. For example, an oxymethylene copolymer can be selected in terms of the balance of heat resistance, mechanical strength, and impact resistance. In this case, the structure of the polyoxymethylene copolymer may be a linear structure, a branched structure, or a cross-linked structure, and It is desirable to include branched ox