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KR-20260067872-A - Polyester polyols for manufacturing polyurethane foam with excellent insulation and demolding property and polyurethane foam comprising the same

KR20260067872AKR 20260067872 AKR20260067872 AKR 20260067872AKR-20260067872-A

Abstract

The present invention discloses a polyester polyol used for manufacturing polyurethane foam that exhibits excellent thermal insulation and demolding properties while improving compatibility with a blowing agent, and a polyurethane foam containing the same. The present invention provides a polyester polyol composition comprising 20 to 50 parts by weight of an acid component including an aromatic dicarboxylic acid; and 30 to 70 parts by weight of an alcohol component represented by the following chemical formula 1, to which 8 to 20 parts by weight of vegetable oil and 2 to 8 parts by weight of a surfactant are added, wherein the acid value is 2 mg KOH/g or less and the hydroxyl value is 360 to 440 mg KOH/g, and a polyurethane foam containing the same. [Chemical Formula 1] HO-X-OH In Chemical Formula 1, X is a straight or branched alkylene group having 2 to 6 carbon atoms substituted or unsubstituted with a hydroxyl group; or a straight or branched ether group having 2 to 6 carbon atoms substituted or unsubstituted with a hydroxyl group.

Inventors

  • 현용빈
  • 우인섭

Assignees

  • 롯데케미칼 주식회사

Dates

Publication Date
20260513
Application Date
20241106

Claims (8)

  1. A polyester polyol composition comprising: 20 to 50 parts by weight of an acid component including an aromatic dicarboxylic acid; and 30 to 70 parts by weight of an alcohol component represented by the following chemical formula 1; a reaction product comprising 8 to 20 parts by weight of vegetable oil; and 2 to 8 parts by weight of a surfactant; wherein the acid value is 2 mg KOH/g or less and the hydroxyl value (OH value) is 360 to 440 mg KOH/g: [Chemical Formula 1] HO-X-OH In Chemical Formula 1, X is a straight or branched alkylene group having 2 to 6 carbon atoms substituted or unsubstituted with a hydroxyl group; or a straight or branched ether group having 2 to 6 carbon atoms substituted or unsubstituted with a hydroxyl group.
  2. In paragraph 1, A polyester polyol composition characterized in that the aromatic dicarboxylic acid comprises phthalic anhydride and terephthalic acid, and the alcohol component comprises diethylene glycol, triethylene glycol, and glycerol.
  3. In paragraph 2, A polyester polyol composition characterized in that the content of the acid component and the alcohol component is 10 to 25 parts by weight of the phthalic anhydride, 10 to 25 parts by weight of the terephthalic acid, 15 to 35 parts by weight of the diethylene glycol, 5 to 15 parts by weight of the triethylene glycol, and 10 to 20 parts by weight of the glycerol.
  4. In paragraph 1, A polyester polyol composition characterized in that the vegetable oil is one or more selected from the group consisting of soybean oil, palm oil, olive oil, castor oil, sunflower oil, corn oil, and rapeseed oil, and the surfactant is one or more selected from the group consisting of polyoxyethylene-polyoxypropylene ether, polyoxyethylene-polyoxypropylene pentaerythritol ether, polyoxypropylene glycol, polyoxypropylene-polyoxyethylene glycerol ether, and polydimethyl siloxane.
  5. In paragraph 1, A polyester polyol composition characterized by the above polyester polyol having a viscosity of 6,000 to 10,000 cPs measured according to the following method, an average number of functional groups of 2.5 to 2.9, and a compatibility of 15 g or more: [Viscosity Measurement Method] The viscosity of the sample was measured at 25°C using a Brookfield viscometer (spindle #64) in accordance with ASTM D4878 standard; [Method for Measuring Average Number of Functional Groups] Measured according to the following mathematical formula 1; <Mathematical Formula 1> In Equation 1, f is the average number of functional groups, n is the number of functional groups of the polyfunctional raw material, EW is the equivalent weight of the polyester polyol (56,100 / OH value), and Y is the yield of polyester polyol per mole of the polyfunctional raw material; [Compatibility Measurement Method] The amount of cyclopentane added to 100 g of a polyester polyol composition in 1 g increments was measured as compatibility just before phase separation occurred.
  6. Polyurethane foam comprising a polyester polyol composition according to any one of claims 1 to 5.
  7. In paragraph 6, A polyester polyol composition characterized in that the above polyurethane foam has a demolding value of 5% or less and a thermal conductivity of 17.4 mW/m·K or less, as measured according to the following method: [Method for measuring demolding] Polyurethane foam liquid is injected into the mold (20% overpacking) and retained in the mold for up to 210 seconds, after which it is demolded. The degree of foam expansion is measured after 2 minutes of curing, wherein the specimen thickness after demolding is the average value measured at 6 locations, the reference mold thickness is 100 mm, and the foam expansion rate is calculated according to the following Equation 2 and used as the demolding measurement value; <Mathematical Formula 2> [Method for Measuring Thermal Conductivity] Measured using NETZSCH’s HFM-446 instrument according to ASTM C518 standards.
  8. In paragraph 6, The above polyurethane foam is characterized by being for use in cooling products.

Description

Polyester polyols for manufacturing polyurethane foam with excellent insulation and demolding properties and polyurethane foam comprising the same The present invention relates to a polyester polyol and a polyurethane foam containing the same, and more specifically, to a polyester polyol having excellent thermal insulation and demolding properties and a polyurethane foam containing the same. Polyurethane foam is widely used in refrigeration products requiring high thermal insulation, such as refrigerators, cold storage warehouses, and refrigerated containers. Polyurethane foam used in these insulation products has traditionally been produced by mixing polyether polyols and polyester polyols, thereby enabling the production of products with excellent thermal conductivity. However, due to recent issues related to energy conservation, there is a demand for the production of products with even higher thermal conductivity. Conventionally, compositions with a high proportion of polyester polyol were used to improve thermal conductivity; however, this presents a problem in that it is difficult to satisfy various conditions, such as compatibility with blowing agents like cyclopentane used in making polyurethane foam and demolding. To address these issues, technologies have been proposed to improve compatibility with foaming agents; however, physical properties such as thermal conductivity and demolding properties were not considered when manufacturing polyurethane foam for cold insulation products. Furthermore, Chinese Patent No. 113174034 utilized amphiphilic polymers to compensate for not only compatibility but also the drawback of reduced compressive strength; however, since this also failed to consider thermal conductivity and demolding properties, it is difficult to apply to cold insulation products. Figure 1 is a photograph of a polyester polyol composition prepared according to Example 1 (A) and Comparative Example 5 (B) for a comparison of compatibility in Test Example 1. Figure 2 is a photograph of polyurethane foam prepared according to Example 5(a) and Comparative Example 12(b) for comparison of demolding in Test Example 2. Preferred embodiments of the present invention are described in detail below. In describing the present invention, detailed descriptions of related prior art are omitted if it is determined that such detailed descriptions may obscure the essence of the present invention. Throughout the 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. The inventors arrived at the present invention by confirming that, in a polyester polyol used for manufacturing polyurethane foam, if a vegetable oil and a surfactant are introduced in a specific ratio into the reaction product of an acid component containing an aromatic dicarboxylic acid and an alcohol component, and the product is made to exhibit a certain level of acid value and hydroxyl value, it is possible to achieve excellent thermal insulation and demolding properties while improving compatibility with a blowing agent. Accordingly, the present invention discloses a polyester polyol composition comprising 20 to 50 parts by weight of an acid component including an aromatic dicarboxylic acid; and 30 to 70 parts by weight of an alcohol component represented by the following chemical formula 1, to a reaction product comprising 8 to 20 parts by weight of vegetable oil; and 2 to 8 parts by weight of a surfactant, wherein the acid value is 2 mg KOH/g or less and the hydroxyl value is 360 to 440 mg KOH/g, and a polyurethane foam produced therefrom. [Chemical Formula 1] HO-X-OH In Chemical Formula 1, X is a straight or branched alkylene group having 2 to 6 carbon atoms substituted or unsubstituted with a hydroxyl group; or a straight or branched ether group having 2 to 6 carbon atoms substituted or unsubstituted with a hydroxyl group. In the present invention, the aromatic dicarboxylic acid may be phthalic anhydride (PA), terephthalic acid (PTA), isophthalic acid (IPA), etc.; however, considering the compatibility with blowing agents such as cyclopentane during foaming after preparation with polyol, and the thermal insulation and demolding properties of the polyurethane foam, it is preferable that the aromatic dicarboxylic acid includes phthalic anhydride and terephthalic acid. At this time, from the perspective of maximizing compatibility with the foaming agent, it is preferable to use the phthalic anhydride in an amount of 10 to 25 parts by weight and the terephthalic acid in an amount of 10 to 25 parts by weight, more preferably the phthalic anhydride in an amount of 12 to 20 parts by weight and the terephthalic acid in an amount of 12 to 20 parts by weight, and even more preferably the phthalic anhydride in an amount of 15 to 18 parts by weight and the terephthalic acid in an amount of 15 to 18 pa