JP2023064301A - Polymer composition, and foam obtained by foaming the same - Google Patents

Abstract

To provide a polymer composition that gives a foam having an improved foaming rate and improved whiteness.SOLUTION: A polymer composition comprises component (a): a polymer, component (b): a foamer, and component (c): at least one hydrazide compound selected from the group consisting of isophthalic dihydrazide (IDH), salicylic hydrazide (SAH), benzoic hydrazide, and urazole.SELECTED DRAWING: None

Description

TECHNICAL FIELD The present invention relates to a polymer composition and a foam obtained by foaming the same.

The applicant of the present invention has conventionally proposed a ceiling material for automobiles comprising a foam layer, wherein the foam layer contains at least one compound selected from hydrazide compounds, azole compounds and azine compounds. We are developing a ceiling material for automobiles (Patent Document 1), etc.

Further, Patent Document 2 describes an expandable polymer comprising (A) a polymer selected from rubber and thermoplastic resins, (B) an organic foaming agent, and (C) a polyfunctional triazine compound. Compositions are disclosed.

JP-A-2000-6730 JP-A-2000-273233

An object of the present invention is to provide a polymer composition for obtaining a foam exhibiting improved expansion ratio and improved whiteness.

In order to solve the above problems, the present inventors have made intensive studies, and as a result, added a specific hydrazide compound to a composition containing a polymer and a foaming agent to foam the composition, resulting in an expansion ratio of The inventors have found that a foam exhibiting an improvement in the heat resistance and an improvement in the whiteness can be obtained.

Based on this knowledge, the inventors have further studied and completed the present invention.

That is, the present invention provides the following polymer composition, a foam obtained by foaming the polymer composition, an expansion ratio improver for a polymer, a method for improving the expansion ratio of a polymer composition, a whiteness improver for a polymer, and methods for improving the whiteness of polymer compositions.

Section 1.
A polymer composition comprising:
component (a): polymer,
Component (b): a foaming agent; and Component (c): a polymer composition comprising at least one hydrazide-based compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole.

Item 2
2. The polymer composition according to claim 1, wherein component (a) is at least one polymer selected from the group consisting of olefinic resins, vinylic resins, and rubber components.

Item 3.
The component (a) is at least one polymer selected from the group consisting of olefin resins and vinyl resins,
The component (c) is at least one compound selected from the group consisting of isophthalic acid dihydrazide and urazole.
3. The polymer composition according to item 1 or 2.

Section 4.
The component (a) is a rubber component,
The component (c) is at least one compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, and benzoic acid hydrazide.
3. The polymer composition according to item 1 or 2.

Item 5.
A foam obtained by foaming the polymer composition according to any one of Items 1 to 4.

Item 6.
An expansion ratio improver for a polymer, comprising at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide and urazole.

Item 7.
A method for improving the expansion ratio of a polymer composition, comprising:
component (a): polymer,
Component (b): a foaming agent; and Component (c): a step of mixing at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole.

Item 8.
A whiteness improver for a polymer, comprising at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide and urazole.

Item 9.
A method for improving the whiteness of a polymer composition, comprising:
component (a): polymer,
Component (b): a foaming agent; and Component (c): a step of mixing at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole.

By foaming the polymer composition of the present invention, it is possible to obtain a foam exhibiting an improved expansion ratio and improved whiteness.

The present invention will be described in detail below.

As used herein, the terms "comprise" and "contain" include "comprise," "consist essentially of," and "consist of." It is a concept.

In this specification, when a numerical range is indicated by "A to B", it means A or more and B or less.

[1] Polymer composition The polymer composition of the present invention is
component (a): polymer,
Component (b): foaming agent, and component (c): containing at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole.

The polymer composition of the present invention may simply be a mixture of component (a), component (b) and component (c), wherein component (a), component (b) and component (c) are ) are mixed in any order.

[1-1] Component (a): Polymer The polymer composition of the present invention contains a polymer as component (a).

The polymer used in the polymer composition of the present invention is preferably at least one polymer selected from the group consisting of olefinic resins, vinylic resins and rubber components.

Component (a) is preferably a polymer excluding carboxyl group-containing resins.

Olefinic Resins The polymers used in the polymer compositions of the present invention are preferably olefinic resins.

The olefinic resin is preferably at least one polyolefinic resin selected from the group consisting of polyethylene (PE), polypropylene (PP), polybutene (PB), polypentene, polyhexene, and polymethylpentene (PMP).

The olefin-based resins may be used alone, or two or more may be mixed (blended) and used.

As polyethylene (PE), low-density polyethylene (LDPE), medium-density polyethylene, high-density polyethylene (HDPE), etc. can be preferably used. PE is preferably low density polyethylene, more preferably (branched) low density polyethylene (LDPE), linear low density polyethylene (LLDPE), even more preferably low density polyethylene (LDPE) is.

By using LDPE in the polymer composition of the present invention, it is possible to obtain a foam exhibiting improved expansion ratio and improved whiteness.

Low density polyethylene (LDPE) is preferably, for example, low density polyethylene polymerized by metallocene catalysts, high pressure low density polyethylene (HP-LDPE) produced by high pressure radical polymerization using radical initiators, transition metal catalysts Linear low-density polyethylene (LLDPE) or the like produced by coordination ionic polymerization is used.

Low density polyethylene (LDPE)
The melt mass flow rate (MFR) of LDPE is determined according to Japanese Industrial Standards JIS K 7210-1: 2014 (ISO 1133-1: 2011). Method-Part 1: Values according to standard test methods. MFR is expressed in grams per 10 minutes (g/10min).

The MFR of LDPE is preferably about 0.1 g/10 min to 50 g/10 min, more preferably about 1 g/10 min to 20 g/10 min, still more preferably 2 g/10 min to 10 g /10 min, particularly preferably about 3 g/10 min to 5 g/10 min.

By using LDPE with an MFR of about 0.1 g/10 min to 50 g/10 min in the polymer composition of the present invention, it is possible to obtain a foam exhibiting an improved expansion ratio and improved whiteness.

The density (kg/m ³ ) of LDPE is a value according to Japanese Industrial Standards JIS K 7112: 1999 Plastics—Methods for measuring density and specific gravity of non-foamed plastics.

The density of LDPE is preferably about 900 kg/m ³ to 950 kg/m ³ , more preferably about 910 kg/m ³ to 940 kg/m ³ , still more preferably about 920 kg/m 3 It is about ³ to 930 kg/m ³ .

By using LDPE with a density of about 900 kg/m ³ to 950 kg/m ³ in the polymer composition of the present invention, it is possible to obtain a foam exhibiting an improved expansion ratio and improved whiteness. .

Vinyl-Based Resin The polymer used in the polymer composition of the present invention is preferably a vinyl-based resin.

Vinyl resins are not particularly limited, and examples thereof include polyvinyl chloride, ethylene-vinyl acetate copolymer, polystyrene, and polyvinyl acetate.

The vinyl resin is preferably at least one polyvinyl resin selected from the group consisting of polystyrene and polyvinyl chloride.

The vinyl-based resin may be used alone, or two or more may be mixed (blended) and used.

Rubber Component The polymer used in the polymer composition of the present invention is preferably a rubber component.

The rubber component is not particularly limited, and examples thereof include diene rubbers, non-diene rubbers, mixtures of diene rubbers and non-diene rubbers, and the like.

Diene rubbers include natural rubber, styrene-butadiene copolymer rubber (SBR), butadiene rubber (BR), isoprene rubber (IR), styrene-isoprene-butadiene rubber (SIBR), nitrile rubber (NBR), chloroprene rubber ( CR), styrene-isoprene-styrene triblock copolymer (SIS), styrene-butadiene-styrene triblock copolymer (SBS), and the like.

Modified diene rubber obtained by modifying these diene rubbers can also be used. Modified diene-based rubbers include diene-based rubbers that have undergone modification techniques such as main chain modification, single-end modification, and both-end modification. Modified functional groups in modified diene rubber include various functional groups such as epoxy groups, amino groups, alkoxysilyl groups, and hydroxyl groups. One or more of these functional groups are contained in the modified diene rubber. Also good.

Natural rubbers include natural rubber latex, technical grade rubber (TSR), smoked sheet (RSS), gutta-percha, Eucommia-derived natural rubber, guayule-derived natural rubber, Russian dandelion-derived natural rubber, and the like.

Modified natural rubbers such as epoxidized natural rubber, methacrylic acid-modified natural rubber, halogen-modified natural rubber, deproteinized natural rubber, maleic acid-modified natural rubber, sulfonic acid-modified natural rubber, styrene-modified natural rubber, etc. Natural rubber can also be used.

Non-diene rubbers include butyl rubber, ethylene-propylene rubber (EPM), ethylene-propylene-diene terpolymer rubber (EPDM), urethane rubber (U), propylene hexafluoride-vinylidene fluoride copolymer (FKM). ), tetrafluoroethylene-propylene copolymer (FEPM), tetrafluoroethylene-perfluorovinyl ether copolymer (FFKM), methyl silicone rubber (MQ), vinyl methyl silicone rubber (VMQ), phenyl methyl silicone rubber ( PMQ), acrylic rubber (ACM), polysulfide rubber (T), epichlorohydrin rubber (CO, ECO), etc.

Modified non-diene rubbers obtained by modifying these non-diene rubbers can also be used. Modified non-diene-based rubbers include non-diene-based rubbers that have undergone modification techniques such as main chain modification, single-end modification, and both-end modification. Modified functional groups of modified non-diene rubber include various functional groups such as epoxy group, amino group, alkoxysilyl group, hydroxyl group, etc. One or more of these functional groups are contained in modified non-diene rubber. It's okay to be there.

The rubber component is preferably from ethylene propylene diene rubber (EPDM), styrene butadiene rubber (SBR), butadiene rubber (BR), natural rubber (NR), isoprene rubber (IR), and isoprene isoprene rubber (IIR). It is at least one kind of rubber selected from the group consisting of

The rubber component may be used singly or as a mixture (blend) of two or more.

[1-2] Component (b): Foaming agent The polymer composition of the present invention contains a foaming agent as component (b).

Component (b) is preferably a chemical foaming agent such as an organic chemical foaming agent or an inorganic chemical foaming agent.

By using a chemical blowing agent such as an organic chemical blowing agent or an inorganic chemical blowing agent in the polymer composition of the present invention, it is possible to obtain a foam exhibiting an improved expansion ratio and an improved whiteness. .

Component (b) is preferably an organic chemical blowing agent.

Organic chemical blowing agents are preferably azodicarbonamide (ADCA), N,N'-dinitrosopentane methylenetetramine, p,p'-oxybisbenzenesulfonyl hydrazide, p-toluenesulfonyl hydrazide, p-toluenesulfonyl semicarbazide , diazoaminobenzene, hydrazodicarbonamide, barium azodicarboxylate, azobisisobutyronitrile, monosodium citrate and other organic acids and metal salts thereof.

The organic chemical blowing agent is preferably an azo chemical blowing agent. The azo chemical blowing agent is preferably at least one azo blowing agent selected from the group consisting of azodicarbonamide (ADCA), barium azodicarboxylate, and azobisisobutyronitrile.

The median diameter of azodicarbonamide (ADCA) is preferably about 1 μm to 30 μm, more preferably 2 μm to 25 μm, still more preferably 4 μm to 20 μm.

By using azodicarbonamide having a median diameter of about 1 μm to 30 μm in the polymer composition of the present invention, it is possible to obtain a foam exhibiting an improved expansion ratio and improved whiteness.

The inorganic chemical foaming agent is preferably an inorganic chemical foaming agent such as sodium bicarbonate, ammonium hydrogen carbonate, sodium carbonate, ammonium carbonate, aluminum acetate, ammonium nitrite, sodium borohydride.

The inorganic chemical blowing agent is preferably baking soda.

Among the foaming agents, azodicarbonamide (ADCA) or sodium bicarbonate is preferred.

The foaming agent may be used alone, or two or more may be mixed (blended) and used.

Surface Treatment of Foaming Agent The surface of the foaming agent (organic chemical foaming agent, inorganic chemical foaming agent) may be chemically treated. Such a foaming agent is excellent in solidification prevention, dispersibility, dust suppression, workability, storage stability, and the like. In addition, compositions and foams obtained by using such foaming agents are excellent in terms of improvement in mechanical properties, miniaturization of cells, and the like.

Compounding amount of component (b) The polymer composition of the present invention preferably contains 0.1 to 50 parts by mass, more preferably 1 part by mass, of component (b) per 100 parts by mass of component (a). It contains up to 30 parts by mass, more preferably 2 parts by mass to 25 parts by mass. The polymer composition of the present invention exhibits improved expansion ratio and whiteness by adding 0.1 to 50 parts by mass of component (b) per 100 parts by mass of component (a). A foam can be obtained.

[1-3] Component (c): Hydrazide Compound In the polymer composition of the present invention, component (c) is selected from the group consisting of isophthalic dihydrazide (IDH), salicylic hydrazide (SAH), benzoic hydrazide, and urazole. It contains at least one selected hydrazide compound.

When the polymer (resin and rubber component) composition of the present invention is kneaded, a specific hydrazide compound is used as the component (c), so that the specific hydrazide compound is added to the polymer in the polymer composition. And it acts on the thermal deterioration mechanism of the blowing agent.

By blending the above-mentioned specific hydrazide compound with the polymer composition of the present invention and foaming it, it is possible to obtain a foam exhibiting an improved expansion ratio and improved whiteness.

The hydrazide compounds used in the present invention include those in the form of salts. The salt of the hydrazide compound is not particularly limited, and examples include inorganic acid salts such as hydrochlorides, sulfates and nitrates; organic acid salts such as acetates and methanesulfonates; alkali metal salts such as sodium salts and potassium salts. salts; alkaline earth metal salts such as magnesium salts and calcium salts; ammonium salts such as dimethylammonium and triethylammonium;

Compounding amount of component (c) The polymer composition of the present invention preferably contains 0.1 to 50 parts by mass, more preferably 0.1 part by mass, of component (c) per 100 parts by mass of component (a). 10 parts by mass, more preferably 0.1 part by mass to 5 parts by mass. The polymer composition of the present invention exhibits an improved expansion ratio and improved whiteness by adding 0.1 to 50 parts by mass of component (c) per 100 parts by mass of component (a). A foam can be obtained.

[1-4] Component (d): Cross-linking agent The polymer composition of the present invention preferably further contains a cross-linking agent as component (d).

The cross-linking agent is preferably dicumyl peroxide (dicumyl peroxide), benzoyl peroxide, dihexyl peroxide, di-t-butylperoxydi-isopropylbenzene, 2,5-dimethyl-2,5-di-( t-butylperoxy)hexane, 2,5-di(t-butylperoxy)-2,5-dimethyl-3-hexyne, p-benzoquinonedioxime, lead oxide, zinc oxide, mercaptobenzothiazole, 2,2' -dibenzothiazolyl disulfide and the like. The cross-linking agent is more preferably dicumyl peroxide.

The cross-linking agent may be used alone, or two or more may be mixed (blended) and used.

Compounding amount of component (d) The polymer composition of the present invention preferably contains 0.1 to 10 parts by mass, more preferably 0.1 part by mass, of component (d) per 100 parts by mass of component (a). 5 parts by mass, more preferably 0.1 to 2 parts by mass. The polymer composition of the present invention exhibits an improved expansion ratio and improved whiteness by adding 0.1 to 10 parts by mass of component (d) per 100 parts by mass of component (a). A foam can be obtained.

[1-5] Component (e): Foaming aid The polymer composition of the present invention preferably contains a foaming aid as component (e).

Foaming aids are preferably urea, mixtures of urea with fatty acids and fatty acid metal salts; urea compounds such as thiourea, tetramethylurea, dimethylthiourea, semicarbazide, and carbohydrazide; zinc oxide, zinc stearate, and zinc benzenesulfinate , zinc toluenesulfonate, zinc trifluoromethanesulfonate, zinc compounds such as zinc carbonate; lead compounds such as lead dioxide and tribasic lead.

The foaming aid may be used singly, or two or more may be mixed (blended) and used.

Foaming aids are preferably component (b) azodicarbonamide, N,N'-dinitrosopentane methylenetetramine, p,p'-oxybisbenzenesulfonyl hydrazide, p-toluenesulfonyl hydrazide, p-toluenesulfonyl semicarbazide , hydrazodicarbonamide and the like, and more preferably, azodicarbonamide.

[1-6] Other Compounding Agents The polymer composition of the present invention preferably contains carbon black, inorganic fillers (silica, etc.), silane coupling agents, anti-aging agents, anti-ozonants, softening agents, and processing aids. , wax, resin, oil, fatty acid with 8 to 30 carbon atoms such as stearic acid, zinc oxide (ZnO), etc. are appropriately selected and blended.

[1-7] Preferred Embodiment of Polymer Composition In a preferred embodiment of the polymer composition of the present invention, component (a) is at least one polymer selected from the group consisting of olefin resins and vinyl resins, Component (c) is a polymer composition comprising at least one compound selected from the group consisting of isophthalic dihydrazide and urazole. In a preferred embodiment of the polymer composition, it is possible to obtain a foam exhibiting improved expansion ratio and improved whiteness.

In a preferred embodiment of the polymer composition of the present invention, component (a) is a rubber component, and component (c) is at least one compound selected from the group consisting of isophthalic dihydrazide, salicylic hydrazide, and benzoic hydrazide. is a polymer composition. In a preferred embodiment of the polymer composition, it is possible to obtain a foam exhibiting improved expansion ratio and improved whiteness.

[2] Foam The present invention is preferably a foam obtained by foaming the polymer composition of the present invention.

By foaming the polymer composition of the present invention, it is possible to obtain a foam exhibiting an improved expansion ratio and improved whiteness.

The foam also includes an aspect in which a molded body is obtained by molding.

In the polymer composition of the present invention, preferably, a foaming agent is added to a polymer such as an olefin resin such as low density polyethylene (LDPE) or a rubber component such as ethylene-propylene-diene terpolymer rubber (EPDM). Furthermore, by blending at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole, when the polymer composition is foamed, a higher expansion ratio is obtained. In addition, a foam having high whiteness can be obtained.

A large amount of polymers, which are petrochemical products, are used in construction materials, industrial materials, infrastructure materials, and the like. From the viewpoint of reducing CO ₂ emissions, it is required to reduce the content of polymers used in these parts. As one of the methods for reducing CO ₂ emissions in these parts, it is possible to reduce the content of polymer used per unit volume by foaming the parts.

The foam of the present invention has a high expansion ratio and can reduce the amount of polymer (resin and rubber component) added per unit volume. The foam of the present invention can reduce the burden on the environment, and can add values such as light weight, mechanical properties, and economic efficiency to the resulting product.

The foam of the present invention has a high degree of whiteness and is useful, for example, for housing materials such as wallpaper, automobile materials, footwear, etc. where whiteness is required. In housing materials, the tint of the base material affects the toning. The foam of the present invention has a high degree of whiteness, and when used as a base material for housing materials, is useful in toning the base material.

[2-1] Foaming ratio index The foam of the present invention is obtained by foaming a composition containing component (a): polymer, component (b): foaming agent, and component (c): hydrazide compound. , is the foam produced.

The foam of the present invention contains components (a) and (b), and is produced by foaming a composition that does not contain component (c). and has a higher expansion ratio.

The expansion ratio index is a value calculated based on the following formula.

Expansion ratio = specific gravity before foam molding / specific gravity after foam molding × 100
Foaming ratio index =
(Expansion ratio of foam produced from the polymer composition of the present invention)
/(Expansion ratio of foam produced from polymer composition not containing component (c))
×100

[2-2] Whiteness index The foam of the present invention can be obtained by foaming a composition containing component (a): polymer, component (b): foaming agent, and component (c): hydrazide compound. , is the foam produced.

The foam of the present invention contains component (a) and component (b), and is produced by foaming a composition that does not contain component (c). It is a foam with an index and a higher whiteness.

The whiteness index is a value calculated based on the following formula.

Whiteness index =
(Hunter Whiteness of Foams Made from Polymer Compositions of the Invention)
/ (Hunter whiteness of foams made from polymer compositions not containing component (c))
×100

[3] Polymer expansion ratio improver and method for improving the expansion ratio of a polymer composition The present invention provides at least one hydrazide compound selected from the group consisting of dihydrazide isophthalate, hydrazide salicylate, hydrazide benzoate, and urazole. It includes an expansion ratio improver for polymers, comprising:

The present invention is a method for improving the expansion ratio of a polymer composition, comprising:
component (a): polymer,
component (b): foaming agent; and component (c): at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole. .

In this specification, the expansion ratio improving agent is different from a foaming aid that promotes foaming by acting on the foaming agent (lowering the decomposition temperature of the foaming agent), and acts on the polymer composition to increase the expansion ratio. It is defined as an agent that can improve.

The foaming ratio improver for polymers of the present invention contains at least one hydrazide compound selected from the group consisting of dihydrazide isophthalate, hydrazide salicylate, hydrazide benzoate, and urazole.

The amount of the foaming ratio improver for polymers is usually 0.01 to 50 parts by mass, preferably 0.05 to 40 parts by mass, per 100 parts by mass of the component (a) in the polymer composition. , more preferably 0.1 to 30 parts by mass, still more preferably 0.5 to 10 parts by mass. The expansion ratio of the polymer composition is improved by adjusting the amount of the polymer expansion ratio improver to be 0.01 parts by mass to 50 parts by mass with respect to 100 parts by mass of the component (a) in the polymer composition. possible and economically preferable.

The polymer expansion ratio improver is preferably at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole itself, but may also contain fillers and the like as appropriate. It may contain other ingredients.

By adding the polymer expansion ratio improver of the present invention to the polymer, the expansion ratio of the polymer composition can be improved.

The present invention includes a method of increasing the expansion ratio of a polymer composition. A method for improving the expansion ratio of a polymer composition comprises: component (a): polymer; component (b): blowing agent; and component (c): dihydrazide isophthalate, hydrazide salicylate, hydrazide benzoate, and urazole. A step of mixing at least one selected hydrazide compound is included.

A method for improving the expansion ratio of the polymer composition may be a step of simply mixing component (a), component (b), and component (c), for example, component (a) and component (c ) may be mixed with component (b). The method of improving the expansion ratio of the polymer composition simply includes mixing component (a), component (b), and component (c) in any order.

[4] Whiteness improver for polymers and method for improving the whiteness of a polymer composition The present invention provides at least one hydrazide compound selected from the group consisting of dihydrazide isophthalate, hydrazide salicylate, hydrazide benzoate, and urazole. A whiteness improver for polymers comprising

The present invention is a method for improving the whiteness of a polymer composition, comprising:
component (a): polymer,
component (b): foaming agent; and component (c): at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole. .

As used herein, a whiteness improver for a polymer acts on the polymer composition to improve Hunter whiteness (lowering the a ^* and b ^* values in the color difference meter (-a ^* , -b ^*, + It is defined as an agent that can act in the direction of L ^* )).

The whiteness improver for polymers of the present invention contains at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole.

The amount of the whiteness improver for polymers is usually 0.01 to 50 parts by mass, preferably 0.05 to 40 parts by mass, per 100 parts by mass of the component (a) in the polymer composition. , more preferably 0.1 to 30 parts by mass, still more preferably 0.5 to 10 parts by mass. The whiteness of the polymer composition is improved by adjusting the amount of the whiteness improver for polymers to be 0.01 to 50 parts by mass with respect to 100 parts by mass of the component (a) in the polymer composition. possible and economically preferable.

The whiteness improver for polymers is preferably at least one hydrazide-based compound selected from the group consisting of diisophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole itself. It may contain other ingredients.

By adding the whiteness improver for polymers of the present invention to a polymer, the whiteness of the polymer composition can be improved.

The present invention includes a method of improving the whiteness of a polymer composition. A method for improving the whiteness of a polymer composition comprises: component (a): polymer; component (b): blowing agent; and component (c): isophthalic dihydrazide, salicylic hydrazide, benzoic hydrazide, and urazol A step of mixing at least one selected hydrazide compound is included.

A method for improving the whiteness of the polymer composition may simply be a step of mixing component (a), component (b), and component (c), for example, component (a) and component (c ) may be mixed with component (b). The method of improving the whiteness of the polymer composition simply includes mixing component (a), component (b), and component (c) in any order.

[5] Uses of Foam The foam of the present invention exhibits an improved expansion ratio and improved whiteness.

Applications of the polymer composition or foam of the present invention are preferably heat insulating materials, lighting materials, building materials, curing materials, joint materials (sealing materials), front door materials, covering materials, waterproof materials, acoustic members ( sound insulation), floaters, cushioning materials, shock absorbing materials, rug core materials, toys, automobile materials, footwear members, and the like.

Applications of the polymer composition or foam of the present invention are preferably thermal insulation, lighting and building materials.

The heat insulating material is, for example, a heat insulating material for piping for transporting a refrigerant, a heat medium, or the like, and a heat insulating material for a floor, a wall, or the like.

The illumination material is, for example, a reflector, a reflector, or the like.

Building materials are, for example, wallpaper, wall boards, pipe covers, and the like. Examples of automotive materials include sound absorbing and damping materials for deadening, automotive interior components such as dashboards, door trims, console boxes, car seats, sun visors, and steering wheel covers, and automotive interior components such as undercovers and door garnishes. .

Examples of footwear members include sneaker uppers, insoles, midsoles, and sandals.

The acoustic member is, for example, a speaker edge, a sound absorbing material, a sound insulating material, a vibration isolating material, a vibration isolating material, or the like.

Examples of sealing materials include rubber packings, oil seals, waterproof materials, perforating materials, weather strips, and glass run channels.

Other uses of the polymer composition or foam of the present invention include tires, hoses, belts, wire coatings, and the like.

Tires are, for example, pneumatic tires (radial tires, bias tires, etc.), solid tires, and the like. Tires are, for example, tires for passenger cars, tires for high loads, tires for motorcycles (motorcycles), studless tires, and the like. In tires, the polymer composition or foam of the present invention can be used for members such as the tread, sidewall, bead area, belt, carcass and shoulder.

Hoses are, for example, radiator hoses, water hoses, concrete transport hoses, and the like.

Belts include transmission belts, conveyor belts, and V-belts.

The wire coating is, for example, a coating for transmission lines.

[6] Method for producing foam The polymer composition of the present invention can be produced by mixing the components (a), (b) and (c). The polymer composition of the present invention is optionally mixed with other ingredients. The order of mixing the components (a), (b), and (c) and the order of blending other compounding agents may be appropriately set.

The foam of the present invention can be produced by foaming a polymer composition containing the components (a), (b) and (c). The foam of the present invention can be produced by heating and foaming a mixture of polymer compositions.

The heating temperature may be at least the temperature at which the mixed component (b) (foaming agent) decomposes, preferably about 50°C to 300°C, more preferably about 80°C to 250°C, and furthermore Preferably, it is about 100°C to 200°C.

The heating time is preferably about 5 seconds to 24 hours, more preferably about 10 seconds to 12 hours, still more preferably about 5 minutes to 3 hours.

Although the embodiments of the present invention have been described above, the present invention is not limited to such examples. The present invention can of course be embodied in various forms without departing from the gist of the present invention.

Hereinafter, embodiments of the present invention will be described more specifically based on examples.

The present invention is not limited to these.

[1] Production of foamed material with high expansion ratio Each component shown in Tables 1 to 3 was mixed at each ratio (parts by mass) in a Banbury mixer. The mixture was then heated in a gear oven at 220°C to produce a high expansion ratio foam.

[2] Expansion ratio index The expansion ratio was calculated by measuring the specific gravity before and after foam molding using an electronic hydrometer (MDS-300 manufactured by ALFA MIRAGE).

Foams (foams of Comparative Examples 1, 7, and 10) were produced using the same compounding content and the same manufacturing method as in each example except that component (c) was not added. and expressed as an index (expansion of expansion ratio) when each expansion ratio is 100.

The expansion ratio index was calculated based on the following formula.

The larger the value of the expansion ratio index, the higher the expansion ratio and the better the foam.

Expansion ratio = specific gravity before foaming (unfoamed) / specific gravity after foaming (foam) x 100
table 1
Expansion ratio index of Example 1=(Expansion ratio of Example 1)/(Expansion ratio of Comparative Example 1)×100
Expansion ratio index of Comparative Examples 2 to 6 = (Expansion ratio of Comparative Examples 2 to 6) / (Expansion ratio of Comparative Example 1) × 100
Table 2
Expansion ratio index of Examples 2-3 = (Expansion ratio of Examples 2-3) / (Expansion ratio of Comparative Example 7) × 100
Expansion ratio index of Comparative Examples 8-9 = (Expansion ratio of Comparative Examples 8-9) / (Expansion ratio of Comparative Example 7) × 100
Table 3
Expansion ratio index of Examples 4-6 = (Expansion ratio of Examples 4-6) / (Expansion ratio of Comparative Example 10) × 100
Expansion ratio index of Comparative Examples 11 to 15 = (Expansion ratio of Comparative Examples 11 to 15) / (Expansion ratio of Comparative Example 10) × 100

[3] Whiteness index Whiteness is determined by measuring L ^* , a ^* , and b ^* of the foam using a spectrophotometer (Konica Minolta CM-5).
Hunter whiteness formula: W _H =100-[(100-L ^* ) ² +a ^*2 +b ^*2 ] ^1/2
Based on, the Hunter whiteness of the foam was calculated.

For the whiteness index of each example and comparative example, foams (foams of comparative examples 1, 7, and 10) were produced with the same formulation content and the same manufacturing method as each example except that component (c) was not added. and expressed as an index (whiteness index) when the whiteness is set to 100.

The whiteness index was calculated based on the following formula.

The larger the value of the whiteness index, the better the whiteness and the better the foam.

table 1
Whiteness index of Example 1 = (whiteness of Example 1) / (whiteness of Comparative Example 1) x 100
Whiteness index of Comparative Examples 2 to 6 = (whiteness of Comparative Examples 2 to 6) / (whiteness of Comparative Example 1) x 100
Table 2
Whiteness index of Examples 2-3 = (whiteness of Examples 2-3) / (whiteness of Comparative Example 7) x 100
Whiteness index of Comparative Examples 8-9 = (Whiteness of Comparative Examples 8-9) / (Whiteness of Comparative Example 7) x 100
Table 3
Whiteness index of Examples 4-6 = (whiteness of Examples 4-6) / (whiteness of Comparative Example 10) x 100
Whiteness index of Comparative Examples 11 to 15 = (whiteness of Comparative Examples 11 to 15) / (whiteness of Comparative Example 10) x 100

[4] Details of each component in Tables 1 to 3 * 1: Sumitomo Chemical Co., Ltd., Sumikasen L-405 (MFR: 3.7 g/10 min (JISK7210-1), density: 924 kg/ ^m3 (JISK7112))
*2: Dicumyl peroxide: NOF, Permil D (crosslinking agent)
*3: Azodicarbonamide, median diameter: 19.5 μm, surface treated *4: Azodicarbonamide, median diameter: 15.0 μm
*5: Isophthalic acid dihydrazide (IDH)
*6: Urazol *7: Salicylic hydrazide (SAH)
*8: Benzoic hydrazide *9: Adipic dihydrazide (ADH)
*10: 2-furoic acid hydrazide *11: 2-thiophenecarboxylic acid hydrazide *12: 3,5-dimethylpyrazole *13: isonicotinic acid hydrazide *14: 3-methyl-1-phenyl-5-pyrazolone *15: Sebacate dihydrazide (SDH)

The polymer composition of the present invention comprises component (a): polymer, component (b): blowing agent, and component (c): isophthalic dihydrazide (IDH), salicylic hydrazide (SAH), benzoic hydrazide, and urazole. By foaming this polymer composition containing at least one hydrazide compound selected from the group, it is possible to obtain a foam exhibiting an improved expansion ratio and improved whiteness.

Claims (9)

A polymer composition comprising:
component (a): polymer,
Component (b): a foaming agent; and Component (c): a polymer composition comprising at least one hydrazide-based compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole. 2. The polymer composition according to claim 1, wherein the component (a) is at least one polymer selected from the group consisting of olefinic resins, vinylic resins, and rubber components. The component (a) is at least one polymer selected from the group consisting of olefin resins and vinyl resins,
The component (c) is at least one compound selected from the group consisting of isophthalic acid dihydrazide and urazole.
3. A polymer composition according to claim 1 or 2. The component (a) is a rubber component,
The component (c) is at least one compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, and benzoic acid hydrazide.
3. A polymer composition according to claim 1 or 2. A foam obtained by foaming the polymer composition according to any one of claims 1 to 4. An expansion ratio improver for a polymer, comprising at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide and urazole. A method for improving the expansion ratio of a polymer composition, comprising:
component (a): polymer,
Component (b): a foaming agent; and Component (c): a step of mixing at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole. A whiteness improver for a polymer, comprising at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide and urazole. A method for improving the whiteness of a polymer composition, comprising:
component (a): polymer,
Component (b): a foaming agent; and Component (c): a step of mixing at least one hydrazide compound selected from the group consisting of isophthalic acid dihydrazide, salicylic acid hydrazide, benzoic acid hydrazide, and urazole.