ALDEHYDE SCAVENGER AND RESIN COMPOSITION

Abstract

The present invention aims to provide an aldehyde scavenger which has excellent aldehyde scavenging properties and yields a resin composition with excellent moldability (mold fouling resistance) when added to a resin. The present invention relates to an aldehyde scavenger containing at least one of: (1) a copolymer (A) containing a (meth)acrylamide (a) and an acid group-containing unsaturated monomer (b) as constituent monomers; and (2) a mixture containing a (co)polymer (B) and a (co)polymer (C), the (co)polymer (B) containing the (meth)acrylamide (a) as a constituent monomer but not containing the acid group-containing unsaturated monomer (b) as a constituent monomer, and the (co)polymer (C) containing the acid group-containing unsaturated monomer (b) as a constituent monomer but not containing the (meth)acrylamide (a) as a constituent monomer.

Claims

1. An aldehyde scavenger comprising at least one of: (1) a copolymer (A) containing a (meth)acrylamide (a) and an acid group-containing unsaturated monomer (b) as constituent monomers; and (2) a mixture containing a (co)polymer (B) and a (co)polymer (C), the (co)polymer (B) containing the (meth)acrylamide (a) as a constituent monomer but not containing the acid group-containing unsaturated monomer (b) as a constituent monomer, and the (co)polymer (C) containing the acid group-containing unsaturated monomer (b) as a constituent monomer but not containing the (meth)acrylamide (a) as a constituent monomer.

2. The aldehyde scavenger according to claim 1, wherein the copolymer (A), the (co)polymer (B), and the (co)polymer (C) each have a weight average molecular weight (Mw) of 2,000 to 100,000.

3. The aldehyde scavenger according to claim 1, wherein a weight ratio [(a)/(b)] of the (meth)acrylamide (a) to the acid group-containing unsaturated monomer (b) is 40/60 to 99/1.

4. The aldehyde scavenger according to claim 1, wherein the copolymer (A) further comprises, as a constituent monomer, at least one monomer (c) selected from the group consisting of a polyoxyalkylene group-containing (meth)acrylic acid ester (c1) and an alkyl group- or hydroxyalkyl group-containing C4-C30 (meth)acrylic acid alkyl ester (c2).

5. The aldehyde scavenger according to claim 1, wherein at least one of the (co)polymer (B) and the (co)polymer (C) further comprises, as a constituent monomer, at least one monomer (c) selected from the group consisting of a polyoxyalkylene group-containing (meth)acrylic acid ester (c1) and an alkyl group- or hydroxyalkyl group-containing C4-C30 (meth)acrylic acid alkyl ester (c2).

6. The aldehyde scavenger according to claim 1, comprising: a product of a neutralization of the copolymer (A) and/or the (co)polymer (C) with the base (E), with a neutralization ratio of 1 to 120%.

7. A resin composition comprising: the aldehyde scavenger according to claim 1; and at least one resin selected from the group consisting of polyester resins, polyacetal resins, polyolefin resins, phenolic resins, urethane resins, melamine resins, urea resins, and urea-melamine resins.

Description

EXAMPLES

[0109] The present invention is described in more detail below with reference to examples, but the present invention is not limited thereto.

[0110] The following lists the formulations, symbols, and the like of the raw materials used in the examples and comparative examples.

<(Meth)acrylamide (a)> [0111] (a-1): acrylamide (Mitsui Chemicals, Inc.)
<Monomer (b)> [0112] (b1-1): acrylic acid [0113] (b1-2): mono(2-acryloyloxyethyl) succinate (Tokyo Chemical Industry Co., Ltd.)
<Other Monomer (c)> [0114] (c1-1): methoxypolyethylene glycol monoacrylate (average number of moles of oxyethylene added: 9) [0115] (c2-1): 2-hydroxyethyl acrylate [0116] (c2-2): dodecyl methacrylate

<Polymerization Initiator>

[0117] AIBN: azobisisobutyronitrile [0118] V-59: 2,2′-azobis(2-methylbutyronitrile)

<Organic Solvent>

[0119] IPA: isopropyl alcohol

[0120] The acid value was determined by potentiometric titration, which is the method specified in JIS K 0070:1992.

Example 1

[0121] A monomer solution was obtained by preparing, at room temperature, a solution mixture containing 472 parts by weight of a 40% by weight aqueous solution of acrylamide (a-1) ((a-1) content: 189 parts by weight), 21 parts by weight of acrylic acid (b1-1), 2.0 parts by weight of mercaptopropionic acid, and 200 parts by weight of IPA.

[0122] Separately, a polymerization initiator solution was obtained by homogeneously dissolving, at room temperature, 2.0 parts by weight of AIBN in 103 parts by weight of IPA.

[0123] A glass reaction vessel (polymerization tank) equipped with a drop inlet, a reflux tube, and a stirring blade was charged with 200 parts by weight of IPA. The contents were heated to 82° C. and refluxed under stirring at 200 rpm. Under reflux conditions and atmospheric pressure, the monomer solution and the polymerization initiator solution were each all added to the vessel over 180 minutes. After the addition, the contents were polymerized for 180 minutes under atmospheric pressure reflux with continuous stirring.

[0124] After the polymerization, the contents were transferred to a recovery flask, and IPA and water were removed at 60° C. using an evaporator. Then, ion-exchange water was added to adjust the concentration of solids to 50% by weight to obtain an aldehyde scavenger (X-1) containing a copolymer (A-1).

Examples 2 to 7 and 12

[0125] Aldehyde scavengers (X-2) to (X-7) and (X-12) containing copolymers (A-2) to (A-7) and (A-12), respectively, were obtained as in Example 1 in accordance with the raw material formulation shown in Table 1. In Examples 5, 7, and 12 for the aldehyde scavengers (X-5), (X-7), and (X-12), after removal of solvents, ammonia water (concentration: 25% by weight) was added, followed by addition of ion-exchange water to adjust the concentration.

Example 8

[0126] Polymerization was performed as in Example 1 in accordance with the raw material formulation (parts by weight) shown in Table 1. After the polymerization, the contents were transferred to a recovery flask, and IPA was removed at 60° C. using an evaporator until the IPA odor was eliminated. The contents remaining in the recovery flask were all transferred to a stainless steel vat and dried using a circulation dryer at 100° C. for about six hours while appropriately mixing the contents with a spatula. The dried product was ground in a table mill to obtain an aldehyde scavenger (X-8) containing 98.2% by weight of a copolymer (A-8). The copolymer (A-8) had an acid value (mg KOH/g) of 39.1. The amount of the copolymer (A) (in terms of solid concentration) in the aldehyde scavenger (X) was determined as follows: the weights (x1) and (x2) of the aldehyde scavenger (X) before drying and after drying using a circulation dryer (130° C., 90 minutes), respectively, were determined; and the copolymer (A) content (100×x2/x1) was calculated using the weights (x1) and (x2). The same procedures were performed in the following examples.

Examples 9 to 11

[0127] Aldehyde scavengers (X-9) to (X-11) were obtained as in Example 8 in accordance with the raw material formulation shown in Table 1.

TABLE-US-00001 TABLE 1 Example 1 2 3 4 5 6 7 Aldehyde scavenger X-1 X-2 X-3 X-4 X-5 X-6 X-7 Copolymer A-1 A-2 A-3 A-4 A-5 A-6 A-7 Raw material Monomer (a-1) 40% 472 499 420 472 357 263 494 formulation solution aqueous solution (parts (a-1) 50% by weight) aqueous solution (a-1) content 189 200 168 189 143 105 198 (b1-1) 21 11 42 21 15 21 13 (b1-2) (c1-1) 53 84 (c2-1) 38 (c2-2) Mercaptopropionic 2.0 1.0 2.0 1.0 acid IPA 200 200 200 200 200 200 200 Polymerization AIBN 2.0 2.0 2.0 2.0 2.0 2.0 2.0 initiator V-59 solution IPA 103 103 103 103 103 103 103 Polymerization IPA 200 200 200 200 200 200 200 tank Ammonia water 10 3 (25% by weight) Properties Mw 7000 12000 6000 11000 7500 10000 16000 of (A) Solid 50 50 50 50 50 50 50 concentration (%) Weight ratio 90/10 95/5 80/20 90/10 90/10 83/17 94/6 [(a)/(b)] Neutralization — — — — 65 — 24 ratio (%) Acid 81.7 40.4 156.5 77.4 59.5 79.4 40.5 value (mgKOH/g) Example 8 9 10 11 12 Aldehyde scavenger X-8 X-9 X-10 X-11 X-12 Copolymer A-8 A-9 A-10 A-11 A-12 Raw material Monomer (a-1) 40% 688 525 263 494 formulation solution aqueous solution (parts (a-1) 50% 450 by weight) aqueous solution (a-1) content 275 210 105 225 198 (b1-1) 18 15 15 13 (b1-2) 135 (c1-1) 73 75 60 (c2-1) 38 (c2-2) 60 Mercaptopropionic 0.4 3.0 1.5 acid IPA 50 50 350 200 Polymerization AIBN 0.9 2.0 initiator V-59 3.7 3.0 3.0 solution IPA 106 150 150 100 103 Polymerization IPA 110 150 150 100 200 tank Ammonia water 13 (25% by weight) Properties Mw 11000 80000 7100 12000 16000 of (A) Solid 98.2 98.1 98 98.6 50 concentration (%) Weight ratio 94/6 93/7 44/56 94/6 94/6 [(a)/(b)] Neutralization — — — — 106 ratio (%) Acid 39.1 38.9 120.0 41.1 40.5 value (mgKOH/g)

Production Example 1

[0128] A monomer solution was obtained by preparing, at room temperature, a solution mixture containing 714 parts by weight of a 40% by weight aqueous solution of acrylamide (a-1) ((a-1) content: 286 parts by weight), 71 parts by weight of methoxypolyethylene glycol monoacrylate (number of moles of oxyethylene added of 9) (c1-1), and 0.4 parts by weight of mercaptopropionic acid.

[0129] Separately, a polymerization initiator solution was obtained by homogeneously dissolving, at room temperature, 3.6 parts by weight of V-59 in 104 parts by weight of IPA.

[0130] A glass reaction vessel (polymerization tank) equipped with a drop inlet, a reflux tube, and a stirring blade was charged with 107 parts by weight of IPA. The contents were heated to 82° C. and refluxed under stirring at 200 rpm. Under reflux conditions and atmospheric pressure, the monomer solution and the polymerization initiator solution were each all added to the vessel over 180 minutes. After the addition, the contents were polymerized under atmospheric pressure reflux for 180 minutes with continuous stirring.

[0131] After the polymerization, the contents were transferred to a recovery flask, and IPA and water were removed at 60° C. using an evaporator. The contents remaining in the recovery flask were all transferred to a stainless steel vat and dried using a circulation dryer at 100° C. for about six hours while appropriately mixing the contents with a spatula. The resulting dry material was ground in a table mill to obtain a powder (BX-1) containing 97.8% by weight of a (co)polymer (B-1).

Production Examples 2 to 5

[0132] Powders (BX-2) and (CX-1) to (CX-3) containing (co)polymers (B-2) and (C-1) to (C-3), respectively, were obtained as in Production Example 1 in accordance with the raw material formulation shown in Table 2.

TABLE-US-00002 TABLE 2 Production Example 1 2 3 4 5 Copolymer B-1 B-2 C-1 C-2 C-3 Raw material Monomer (a-1) 40% 714 formulation solution aqueous solution (parts (a-1) 50% 480 by weight) aqueous solution (a-1) content 286 240 0 0 0 (b1-1) 320 80 240 (d-1) 71 80 320 (c2-2) 60 160 Mercaptopropionic 0.4 1.0 4.0 4.0 2.0 acid IPA 350 50 50 200 Ion-exchange water 150 150 Polymerization V-59 3.6 3.0 4.0 4.0 4.0 initiator solution IPA 104 100 150 150 150 Polymerization IPA 107 100 150 150 200 tank Ion-exchange water 50 50 Properties Mw 10500 13000 17000 13000 14000 of (B) and (C) Solid 97.8 98.4 98.0 97.2 98.1 concentration (%) Weight ratio 100/0 100/0 0/100 0/100 0/100 [(a)/(b)] Acid 0.5 1.7 618 158 464 value (mgKOH/g)

Examples 13 to 15

[0133] In accordance with the formulation shown in Table 3, aldehyde scavengers (X-13) to (X-15) were obtained by powder blending any of powders (BX-1) and (BX-2) and (CX-1) to (CX-3) containing copolymers (B-1) and (B-2) and (C-1) to (C-3), respectively.

TABLE-US-00003 TABLE 3 Example 13 14 15 Aldehyde scavenger X-13 X-14 X-15 Raw material formulation (B-1) 90 40 (parts by weight (B-2) 90 (C-1) 10 (C-2) 60 (C-3) 10

[0134] The obtained aldehyde scavengers (X-1) to (X-15) were evaluated by the evaluation method described below. For comparison, adipic acid dihydrazide was used as it is as an aldehyde scavenger (Comparative X-1).

Comparative Production Example 1

[0135] A beaker was charged with 70 parts by weight of polyacrylamide (Sigma-Aldrich, Mn =40000) and 30 parts by weight of polyethylene glycol (PEG-400, Mn =400, available from Sanyo Chemical Industries, Ltd.). The contents were mixed with a spatula until a homogeneous mixture was obtained. Thus, an aldehyde scavenger (Comparative X-2) for comparison was obtained.

Examples 21 to 28 and Comparative Example 21

Evaluation Method

<1> Scavenging Properties in Aqueous Urea-Melamine Resin Solution

<1-1> Synthesis of Urea-Melamine Resin

[0136] A reaction vessel was charged with 50 parts by weight of urea, 62 parts by weight of melamine, 220 parts by weight of a 37% by weight aqueous formaldehyde solution, and 14.0 parts by weight of methanol. The contents were stirred at 25° C.

[0137] Another vessel was charged with 144 parts by weight of ion-exchange water and 3.0 parts by weight of sodium hydroxide to prepare an aqueous sodium hydroxide solution.

[0138] The entire sodium hydroxide solution was added to the reaction vessel. The contents were stirred at 90° C. for two hours and cooled to room temperature to obtain an aqueous urea-melamine resin solution (40% by weight concentration). The concentration of free formaldehyde in the aqueous resin solution was 3% by weight.

<1-2> Scavenging Properties in Aqueous Solution

[0139] In accordance with the compounding formulation shown in Table 4, a solution mixture containing 100 parts by weight of the aqueous urea-melamine resin solution and 15 parts by weight of any of the aldehyde scavengers (X-1) to (X-7) and (X-12) or 7.5 parts by weight of the aldehyde scavenger (Comparative X-1) was mixed at 40° C. for three hours with stirring. The formaldehyde content of the aqueous solution after mixing was determined according to determination of free formaldehyde content in JIS K 6807. The results of determination of free formaldehyde content (% by weight) of the aqueous solution are shown in Table 4.

TABLE-US-00004 TABLE 4 Comparative Example Example 21 22 23 24 25 26 27 28 21 Compounding Aldehyde X-1 15 formulation scavenger X-2 15 (parts by X-3 15 weight) X-4 15 X-5 15 X-6 15 X-7 15 X-12 15 Comparative 7.5 X-1 Aqueous urea-melamine 100 100 100 100 100 100 100 100 100 resin solution Evaluation Free formaldehyde content 0.50 0.80 0.65 0.52 0.70 0.94 0.86 0.87 3.2 (% by weight) of aqueous solution

Examples 31 to 38 and Comparative Example 31

<2> Scavenging Properties in Phenolic Resin

<2-1> Production of Phenolic Resin Cured Product

[0140] A reaction vessel was charged with 100 parts by weight of phenol and 250 parts by weight of a 30% by weight aqueous formaldehyde solution. The contents were stirred at 25° C.

[0141] To the reaction vessel was added 8.0 parts by weight of a 50% by weight aqueous sodium hydroxide solution. The contents were stirred at 65° C. for three hours and cooled to room temperature. Additionally, 89.5 parts by weight of ion-exchange water was added to obtain an aqueous phenolic resin solution (phenolic resin content: 40% by weight).

[0142] In accordance with the compounding formulation shown in Table 5, 100 parts by weight of the aqueous phenolic resin solution, 4 parts by weight of any of the aldehyde scavengers (X-1) to (X-7) and (X-12) or 2 parts by weight of the aldehyde scavenger (Comparative X-1), and ion-exchange water were mixed to prepare a 20% by weight phenolic resin solution mixture. A filter paper corresponding to a 5C filter paper was impregnated with the solution mixture, and reaction was performed at 180° C. for five minutes to obtain a filter paper specimen containing a phenolic resin cured product.

<2-2> Amount of Aldehyde Released

[0143] First, 100 mL of distilled water and the prepared filter paper specimen (100 mm×100 mm) were sealed in a glass desiccator (desiccator plate: 240 mm in diameter) and allowed to stand at 20° C. for 24 hours. The amount of formaldehyde dissolved in the distilled water was measured spectrophotometrically to determine an amount of aldehydes released (mg/L). The results are shown in Table 5.

<2-3> Tensile Strength

[0144] The filter paper specimen was cut into a 50 mm×20 mm piece, which was subjected to measurement of tensile strength using an autograph (AGS-500D available from Shimadzu Corp.) at a speed of 10 mm/min.

[0145] The results are shown in Table 5. The tensile strength in the case where no aldehyde scavenger (X) was added was 9.4 N.

<2-4> Moldability (Mold Fouling Resistance)

[0146] Each of the 20% phenolic resin solution mixtures containing the aldehyde scavenger obtained in <2-1> was dehydrated to obtain a phenolic resin mixture (resin composition). The resulting phenolic resin mixture was applied to a SUS420J2 test piece and reacted at 180° C. for five minutes to obtain a phenolic resin cured product, which was peeled off. This process was performed 20 times consecutively. The condition of the surface of the test piece was observed and evaluated using the following <Evaluation criteria>. The results are shown in Table 5.

<Evaluation Criteria>

[0147] Excellent: No deposits are on the surface of the test piece at all. [0148] Good: Almost no deposits are on the surface of the test piece. [0149] Fair: A small amount of deposits are on the surface of the test piece. [0150] Poor: A large amount of deposits are on the surface of the test piece.

[0151] The resin compositions obtained in Examples 31 to 38 had better moldability (mold fouling resistance) than the resin composition obtained in Comparative Example 31.

TABLE-US-00005 TABLE 5 Comparative Example Example 31 32 33 34 35 36 37 38 31 Compounding Aldehyde X-1 4 formulation scavenger X-2 4 (parts by X-3 4 weight) X-4 4 X-5 4 X-6 4 X-7 4 X-12 4 Comparative 2 X-1 Ion-exchange water 96 96 96 96 96 96 96 96 98 Aqueous phenolic 100 100 100 100 100 100 100 100 100 resin solution Evaluation Amount of 0.38 0.66 0.49 0.37 0.65 0.68 0.55 0.55 0.85 formaldehyde released (mg/L) Mold fouling Excel- Excel- Excel- Excel- Excel- Excel Excel- Excel- Fair resistance lent lent lent lent lent lent lent lent Tensile 11.5 10.8 10.5 11.2 10.4 10.6 11.0 11.1 8.2 strength (N)

Examples 41 to 48 and Comparative Example 41

<3> Scavenging Properties in Wooden Board

<3-1> Production of Wooden Board

[0152] First, 100 parts by weight of particleboard lauan chips (weight average particle size: about 1.5 mm) dried for six hours using a circulation dryer at 130° C. were cooled to room temperature (25° C.)

[0153] Next, in accordance with the compounding formulation shown in Table 6, 100 parts by weight of the chips obtained were mixed by stirring with a solution mixture containing 5 parts by weight of Oshika Resin MG-200 (melamine resin solution, available from Oshika Corporation) and 0.3 parts by weight of any of the aldehyde scavengers (X-1) to (X-7) and (X-12) or 0.15 parts by weight of the aldehyde scavenger (Comparative X-1).

[0154] The mixture was thermally compressed at 130° C. and at 25 kgf/cm.sup.2 for 1.5 minutes using an SKD11 metal plate to produce a wooden board having a specific gravity of 0.7 and a thickness of 3 mm.

<3-2> Moldability (Mold Fouling Resistance)

[0155] The above-described production of the wooden board by thermal compression was performed 50 times consecutively. The condition of the surface of the SKD11 metal plate was observed and evaluated using the following <Evaluation criteria>. The results are shown in Table 6.

<Evaluation Criteria>

[0156] Excellent: No deposits are on the metal plate surface at all. [0157] Good: Almost no deposits are on the metal plate surface. [0158] Fair: A small amount of deposits are on the metal plate surface. [0159] Poor: A large amount of deposits are on the metal plate surface.

[0160] The moldability during the production of the wooden board was better when any of the mixtures obtained in Examples 41 to 48 (compositions each containing melamine resin and any of the aldehyde scavengers (X)) was used than when the mixture obtained in Comparative Example 41 (composition containing melamine resin and the aldehyde scavenger (Comparative X-1)) was used.

<3-3> Amount of Formaldehyde Released

[0161] A 100 mm×100 mm molded specimen was cut from the wooden board. First, 50 mL of distilled water and the prepared molded specimen (100 mm×100 mm×3 mm) were sealed in a glass desiccator (desiccator plate: 240 mm in diameter) and allowed to stand at 30° C. for 24 hours. The amount of formaldehyde dissolved in the distilled water was measured spectrophotometrically to determine an amount of formaldehyde released (unit: mg/L). The results are shown in Table 6.

<3-4> Flexural Strength of Wooden Board

[0162] The flexural strength of the wooden board was measured according to the test method of JIS A 5908. The following describes the details of the test method. A 20 mm x 200 mm specimen was cut from the produced wooden board and subjected to measurement of flexural strength (N) using an autograph (AGS-500D available from Shimadzu Corp.) at a speed of 10 mm/min. The results are shown in Table 6.

[0163] The flexural strength in the case where no aldehyde scavenger (X) was added was 17.2 N.

TABLE-US-00006 TABLE 6 Comparative Example Example 41 42 43 44 45 46 47 48 41 Compounding Aldehyde X-1 0.3 formulation scavenger X-2 0.3 (parts by X-3 0.3 weight) X-4 0.3 X-5 0.3 X-6 0.3 X-7 0.3 X-12 0.3 Comparative 0.15 X-1 Oshika 5 5 5 5 5 5 5 5 5 Resin MG-200 Particleboard 100 100 100 100 100 100 100 100 100 lauan chip Evaluation Amount of 0.6 0.7 0.7 0.6 0.8 0.8 0.7 0.7 1.3 formaldehyde released (mg/L) Mold fouling Excel- Excel- Excel- Excel- Excel- Excel- Excel- Excel- Poor resistance lent lent lent lent lent lent lent lent Flexural 19.1 18.2 17.8 18.5 17.8 18.4 18.9 19.0 16.4 strength (N)

Examples 51 to 58 and Comparative Example 51

[0164] <4> Scavenging Properties in Urethane Resin (Polyurethane Foam)

<4-1> Production of Polyurethane Foam

[0165] In accordance with the compounding formulation shown in Table 7, 100 parts by weight of polyol (SANNIX KC760, available from Sanyo Chemical Industry Ltd.), 100 parts by weight of polyisocyanate (TDI-80/Crude MDI=80/0 (weight ratio), NCO %=44.6], 3 parts by weight of ion-exchange water, 1 part by weight of a urethanization catalyst (RZETA, available from Tosoh Corp.), 1 part by weight of a urethanization catalyst (DABCO, NE300, available from Air Products Japan, Inc.), and 1 part by weight of any of the aldehyde scavengers (X-1) to (X-7) and (X-12) or 0.5 parts by weight of the aldehyde scavenger (Comparative X-1) were stirred in Homodisper (mixer available from Tokushu Kika Kogyo Co., Ltd.) at 4000 rpm for six seconds. The mixture was injected into an aluminum mold (300 mm (length)×300 mm (width)×100 mm (height)) whose temperature was controlled to 65° C., and molded by curing for five minutes (the duration from the raw material injection to demolding). Thus, a polyurethane foam (foam density: 45 kg/m.sup.3) was obtained.

<4-2> Moldability (Mold Fouling Resistance)

[0166] The above-described production of the polyurethane foam was performed 20 times consecutively. The condition of the surface of the aluminum mold was observed and evaluated using the following <Evaluation criteria>. The results are shown in Table 7.

<Evaluation Criteria>

[0167] Excellent: No deposits are on the aluminum mold surface at all. [0168] Good: Almost no deposits are on the aluminum mold surface.

[0169] Fair: A small amount of deposits are on the aluminum mold surface. [0170] Poor: A large amount of deposits are on the aluminum mold surface. [0171] The polyurethane foams obtained in Examples 51 to 58 had better moldability (mold fouling resistance) than the polyurethane foam obtained in Comparative Example 51.

<4-3> Amount of Aldehyde Released

[0172] A foam sample for aldehyde content measurement having a size of 100 mm×100 mm×33 mm was cut from a center portion of each of the polyurethane foams.

[0173] Aldehydes volatilized from the polyurethane foam were collected in a 2,4-dinitrophenylhydrazine (DNPH) cartridge according to the procedures described in JASO M903 (2015).

[0174] The amount of the aldehydes collected in the DNPH cartridge was determined as follows: the aldehydes were extracted with 5 mL of acetonitrile from the cartridge; and the extract was analyzed by HPLC. The HPLC was performed under the following conditions. The calibration curves were prepared by diluting a 6 aldehyde compounds mixture standard solution (FUJIFILM Wako Pure Chemical Corporations Co., Ltd.) with acetonitrile. The amount of aldehydes (pg/g) volatilized from the polyurethane foam is expressed as a value per gram of the sample. The measurement results of formaldehyde, acetaldehyde, and propionaldehyde are shown in Table 7.

<HPLC Measurement Conditions>

[0175] HPLC: ACQUITY UPLC H-CLASS available from Waters Corporation [0176] Column: ZORBAX Eclipse XDB-C8, 4.6×250 mm, 5 μm [0177] Developing solution: acetonitrile/water (volume ratio)=50/50 [0178] Injection volume: 20 μL [0179] Flow rate: 0.8 mL/min

<4-4> Measurement of Physical Properties of Polyurethane Foam

[0180] The physical properties were determined as follows. Hardness at 25° C. (25%-ILD): in accordance with JIS K 6400 (Unit: N/314 cm.sup.2) [0181] Tensile strength: in accordance with JIS K 6400 (Unit: N/cm.sup.2)

[0182] The results are shown in Table 7. The hardness at 25° C. (25%-ILD) was 52 N/314 cm.sup.2 and the tensile strength was 3.7 N/cm.sup.2 when no aldehyde scavenger (X) was added.

TABLE-US-00007 TABLE 7 Comparative Example Example 51 52 53 54 55 56 57 58 51 Compounding Aldehyde X-1 1 formulation scavenger X-2 1 (parts by X-3 1 weight) X-4 1 X-5 1 X-6 1 X-7 1 X-12 1 Comparative 0.5 X-1 DABUCO NE300 1 1 1 1 1 1 1 1 1 RZETA 1 1 1 1 1 1 1 1 1 Ion-exchange water 3 3 3 3 3 3 3 3 3 Polyisocyanate 100 100 100 100 100 100 100 100 100 SANNIX KC760 100 100 100 100 100 100 100 100 100 Evaluation Amount of 0.003 0.003 0.004 0.003 0.004 0.005 0.005 0.005 0.006 formaldehyde released (μg/g) Amount of 0.01 0.009 0.01 0.008 0.12 0.011 0.012 0.012 0.015 acetaldehyde released (μg/g) Amount of 0.012 0.011 0.012 0.01 0.011 0.012 0.014 0.013 0.02 propionaldehyde released (μg/g) Mold fouling Excel- Excel- Excel- Excel- Excel- Excel- Excel- Excel- Fair resistance lent lent lent lent lent lent lent lent Hardness at 25° C. 56 55 53 54 55 53 56 56 51 (25% ILD) (N/314 cm.sup.2) Tensile strength 3.8 3.8 3.7 3.7 3.8 3.9 3.7 3.8 3.6 (N/cm.sup.2)

Examples 61 to 65 and Comparative Examples 61 to 63

<5> Scavenging Properties in Polyacetal Resin

<5-1> Production of Polyacetal Resin Composition and Molded Article

[0183] In accordance with the compounding formulation (parts by weight) shown in Table 8, the components to be compounded were blended using a Henschel mixer for three minutes and then melt-kneaded in a vented twin-screw extruder at 100 rpm and at 200° C. with a residence time of five minutes. Thus, polyacetal resin compositions were obtained. The polyacetal resin used was DURACON M90-44 (standard grade) available from Polyplastics Co. Ltd.

[0184] The resulting polyacetal resin compositions were each molded using an injection molding machine (“PS40E5 ASE” available from Nissei Plastic Industrial Co., Ltd.) at a cylinder temperature of 210° C. and a mold temperature of 60° C. Thus, molded articles were produced and evaluated by the following performance tests. The results are shown in Table 8.

<5-2> Amount of Formaldehyde Released

[0185] <Evaluation of Aldehyde Scavenging properties>(VDA 275 method)

[0186] A 1-L polyethylene container was charged with 50 mL of distilled water and any of the above-described molded specimens (100×40×3 mm) produced using the injection molding machine (each molded specimen produced had been allowed to stand at room temperature for 24 hours in a plastic bag with a zipper). The contents were sealed and heated at 60° C. for three hours. The formaldehyde dissolved in the distilled water was reacted with acetylacetone in the presence of ammonium ions at 60° C. for 10 minutes. The absorption peaks of the reaction product were obtained by spectrophotometric analysis, and the amount of formaldehyde released per weight of the specimen (μg/g) was determined from the absorption peak at a wavelength of 412 nm.

<5-3> Moldability (Mold Fouling Resistance)

[0187] The above-described injection molding was performed 500 times consecutively, and the condition of the surface of the mold was observed and evaluated using the following <Evaluation criteria>.

<Evaluation Criteria>

[0188] Excellent: No deposits are on the metal mold surface at all. [0189] Good: Almost no deposits are on the metal mold surface. [0190] Fair: A small amount of deposits are on the metal mold surface. [0191] Poor: A large amount of deposits are on the metal mold surface.

<5-4> Flexural Strength, Flexural Modulus (Evaluation of Mechanical Strength of Molded Article)

[0192] A molded specimen (80×10×4 mm) was subjected to measurement of flexural strength and flexural modulus at 23° C. in accordance with ISO 178.

[0193] The flexural strength was 70 MPa and the flexural modulus was 1900 MPa when no aldehyde scavenger (X) was added.

TABLE-US-00008 TABLE 8 Example Comparative Example 61 62 63 64 65 61 62 63 Compounding Aldehyde X-8 0.3 formulation scavenger X-9 0.3 (parts by X-10 0.3 weight) X-13 0.3 X-14 0.3 Comparative X-1 0.1 0.5 Comparative X-2 0.3 DURACON M90-44 100 100 100 100 100 100 100 100 Evaluation Amount of formaldehyde 0.4 0.5 0.7 0.8 0.7 4.3 1.4 3.6 released (μg/g) Mold fouling resistance Excellent Excellent Excellent Excellent Excellent Fair Poor Poor Flexural strength (MPa) 71 71 70 70 70 70 70 69 Flexural modulus (MPa) 1900 1910 1890 1900 1900 1890 1900 1880

Examples 71 and 72 and Comparative Examples 71 and 72

<6> Scavenging Properties in Polyolefin Resin

<6-1> Production of Polyolefin Resin Composition and Molded Article

[0194] In accordance with the compounding formulation shown in Table 9, the components to be compounded were blended using a Henschel mixer for three minutes and then melt-kneaded in a vented twin-screw extruder at 100 rpm and at 230° C. with a residence time of five minutes. Thus, polyolefin resin compositions were obtained. The resulting resin compositions were each cut into pellets using a pelletizer. The polyolefin resin used was “Daicel PP PT2N1” available from Daicel Miraizu Ltd.

[0195] The resulting polyolefin resin compositions were each then molded using an injection molding machine (“PS40E5 ASE” available from Nissei Plastic Industrial Co., Ltd.) at a cylinder temperature of 230° C. and a mold temperature of 60° C. Thus, molded articles were produced and evaluated by the following performance tests. The results are shown in Table 9.

<6-2> Amount of Aldehyde Released

<Evaluation of Aldehyde Scavenging Properties>

[0196] The pelletized sample in an amount of 200 g was placed in a 10 liter (L) (gas volume) Tedlar® polyvinyl fluoride (PVF) bag (available from Delin Co., Ltd., China), and to the bag was supplied 5 L of nitrogen. The sample was allowed to stand at 65° C. for two hours. Then, nitrogen gas in the gas bag was discharged with an air pump at 330 mL/min over 13 minutes. The released carbonyls were absorbed on a DNPH cartridge (CNWBOND DNPH-silica cartridge, 350 mg, catalog no. SEEQ-144102, available from Anple Co., Ltd.).

[0197] After the absorption, the DNPH cartridge was clutch with 1 g (accurately weighed) of acetonitrile (ACN), and the ACN solution was analyzed by HPLC to quantify the carbonyls in the sample.

[0198] The calibration curves were prepared by diluting a 6 aldehydes-DNPH mixture standard solution (FUJIFILM Wako Pure Chemical Corporations Co., Ltd.) with acetonitrile.

<HPLC Measurement Conditions>

[0199] HPLC: ACQUITY UPLC H-CLASS available from Waters Corporation [0200] Column: WAKO-PAK WAKOSIL-DNPH 4.6×250 ram Developing solution:

[0201] (A) Wakosil®, DNPH eluent A

[0202] (B) Wakosil®, DNPH eluent B [0203] Gradient (Liquid B concentration (%) is expressed in vol%) [0204] 0 to 16 min B: 10% [0205] 16 to 35 min B: 10 to 90% [0206] 35 to 45 min B: 90% [0207] Injection volume: 20 pL [0208] Flow rate: 0.6 mL/min

<6-3> Tensile Strength, Flexural Strength, Flexural Modulus (Evaluation of Mechanical Strength of Molded Article)

[0209] The tensile strength was measured at 23° C. in accordance with ISO 527.

[0210] The flexural strength and flexural modulus were measured at 23° C. in accordance with ISO 178.

[0211] The tensile strength was 24 MPa, the flexural strength was 38 MPa, and the flexural modulus was 2800 MPa when no aldehyde scavenger (X) was added.

<6-4> Moldability (Mold Fouling Resistance)>

[0212] The above-described injection molding was performed 500 times consecutively, and the condition of the surface of the mold was observed and evaluated using the following <Evaluation criteria>.

<Evaluation criteria> [0213] Excellent: No deposits are on the metal mold surface at all. [0214] Good: Almost no deposits are on the metal mold surface. [0215] Fair: A small amount of deposits are on the metal mold surface. [0216] Poor: A large amount of deposits are on the metal mold surface.

TABLE-US-00009 TABLE 9 Example Comparative Example 71 72 71 72 Compounding Aldehyde X-11 0.3 formulation scavenger X-15 0.3 (parts) Comparative X-1 0.1 0.5 Talc (JetFil700) 15 15 15 15 Daicel PP PT2N1 85 85 85 85 Evaluation Amount of formaldehyde 0.09 0.11 0.22 0.18 released (mg/m.sup.3) Amount of acetaldehyde 0.6 0.9 2.1 1.5 released (mg/m.sup.3) Amount of hexanal 0.7 0.9 1.8 1.3 released (mg/m.sup.3) Mold fouling resistance Excellent Excellent Fair Poor Tensile strength (MPa) 24 24 24 24 Flexural strength (MPa) 39 39 38 37 Flexural modulus (MPa) 2900 2800 2800 2700

[0217] The results in Tables 4 to 9 show that the aldehyde scavengers (X) of the present invention have better aldehyde scavenging properties than the comparative ones. The resins containing the aldehyde scavengers (X) of the present invention have excellent moldability (mold fouling resistance). Use of the aldehyde scavengers (X) of the present invention can reduce the amount of aldehydes released and can yield a resin composition having excellent moldability (mold fouling resistance). Furthermore, when the aldehyde scavenger (X) is added to the resin (D) containing formaldehyde as a constituent monomer (urea-melamine resin, phenolic resin, or melamine resin), urethane resins, polyacetal resins, or polyolefin resins, the mechanical strength of these resins does not decrease.

INDUSTRIAL APPLICABILITY

[0218] The aldehyde scavenger of the present invention can be used as various aldehyde scavengers. In particular, the aldehyde scavenger is suitable and very useful as aldehyde scavengers for resins containing formaldehyde as a constituent monomer, aldehyde scavengers for urethane resins, aldehyde scavengers for polyacetal resins, and aldehyde scavengers for polyolefin resins.