Polyurethane foam, and cushioning material, sealing material, and heat insulating material using said polyurethane foam

Abstract

The present invention provides a polyurethane foam that uses a biomass feedstock and has high density and excellent physical properties. The present technology provides a polyurethane foam which contains a biomass-derived polyol as a polyol component, has a density of greater than or equal to 120 kg / m3, and has an isocyanate index of less than or equal to 92. The present technology also provides a polyurethane foam that contains a biomass-derived polyol as a polyol component, has a density of greater than or equal to 120 kg / m3, and has an elongation rate of greater than or equal to 200% as measured in accordance with JIS K6401:2011.

Description

Polyurethane foam, and cushioning material, sealing material, and heat insulating material using the polyurethane foam

[0001] The present technology relates to polyurethane foams, and more particularly to cushioning materials, sealing materials, and heat insulating materials using the polyurethane foams.

[0002] Polyurethane foams are widely used in a variety of fields, including furniture such as sofas and chairs, bedding such as mattresses and pillows, clothing such as underwear, daily necessities such as dishwashing and cleaning sponges, interior products for vehicles and aircraft such as car seats, electronic devices such as mobile phones, cameras, and televisions, electrical appliances such as home appliances, toys, and miscellaneous goods. Various developments are underway to improve quality and add new functions according to each field and purpose.

[0003] Furthermore, in recent years, in order to contribute to the formation of a sustainable society, technology utilizing biomass raw materials as so-called carbon-neutral renewable resources for polyurethane foams has also attracted attention. For example, Patent Document 1 discloses a rigid polyurethane foam obtained by reacting a polyol composition containing 30% by weight or more of a biomass-derived polyol with a polyisocyanate, the polyurethane foam having a degree of interconnected cells of 65% or more and a specific value obtained by dividing the compressive strength by the density, thereby exhibiting strength properties comparable to those of foams derived from conventional synthetic polyols.

[0004] Furthermore, Patent Document 2 discloses a technology for producing a flexible, low-resilience polyurethane foam based on the reaction product of an isocyanate-reactive component and an isocyanate component that is substantially free of aromatic isocyanates that contain isocyanate groups directly bonded to aromatic rings.

[0005] JP 2004-315548 A JP 2012-509368 A

[0006] In recent years, there has been an increasing demand for polyurethane foams that can be used as cushioning materials for absorbing vibrations and shocks in electronic devices such as mobile phones, cameras, and televisions, and electrical devices such as home appliances, as sealing materials for various batteries, and as sealing and insulating materials for the periphery of batteries and electronic control units in electric vehicles.High density is required for these applications, but high-density polyurethane foams made from biomass raw materials are still in the development stage.

[0007] Therefore, the main objective of this technology is to provide a polyurethane foam that uses biomass raw materials and has high density and excellent physical properties.

[0008] In this technology, first, a biomass-derived polyol is contained as a polyol component, and the density is 120 kg / m 3 or more, and has an isocyanate index of 92 or less. The present technology also provides a polyurethane foam containing a biomass-derived polyol as a polyol component, and having a density of 120 kg / m 3 The present invention provides a polyurethane foam having an elongation of 200% or more as measured in accordance with JIS K6401:2011. The polyurethane foam according to the present technology may have a glass transition temperature of 5°C or less. The polyurethane foam according to the present technology may have a biomass content of 20% or more. The polyurethane foam according to the present technology can be used as a cushioning material, a sealing material, or a heat insulating material.

[0009] Preferred embodiments for implementing the present technology will be described below. The embodiments described below are examples of typical embodiments of the present technology, and any of the embodiments can be combined. Furthermore, the scope of the present technology is not to be interpreted narrowly by these embodiments.

[0010] 1. Composition for Producing Polyurethane Foam The polyurethane foam according to the present technology is produced using a composition containing a polyol and an isocyanate. The composition used for producing the polyurethane foam according to the present technology may also contain fillers, catalysts, antioxidants, moisture absorbents, foam stabilizers, blowing agents, etc., as necessary.

[0011] The polyurethane foam according to the present technology is preferably produced using a mechanical froth method, as described below. That is, the composition used for producing the polyurethane foam according to the present technology can be suitably used as a composition for mechanical froth. Each component will be described in detail below.

[0012] (1) Polyol The polyurethane foam according to the present technology is characterized by containing a biomass-derived polyol as a polyol component. In addition, one or more polyols used in general polyurethane foams can be freely selected and used depending on the physical properties and applications of the polyurethane foam to be produced.

[0013] (1-1) Biomass-derived polyol The biomass-derived polyol that can be used in the present technology can be freely selected from one or more biomass-derived polyols that can be used in the production of polyurethane foam, as long as the action and effect of the present technology are not impaired.

[0014] Examples of biomass-derived polyols that can be used in the present technology include 1,3-propanediol derived from plants or animals, such as corn, 1,2,3-propanetriol (glycerin) derived from plants or animals, or condensates thereof, natural fats and oils such as castor oil, soybean oil, palm oil, palm kernel oil, coconut oil, cashew nut shell liquid (CNSL), cashew nut oil, olive oil, cottonseed oil, safflower oil, sesame oil, sunflower oil, and linseed oil, or derivatives thereof (e.g., modified natural fat and oil polyols, unmodified natural fat and oil polyols, etc.). Among these, in the present technology, it is preferable to use a biomass-derived polyether polyol, and it is more preferable to use a condensate of 1,3-propanediol derived from plants or animals as the biomass-derived polyether polyol, and it is even more preferable to use poly(trimethylene ether) glycol prepared from 1,3-propanediol derived from plants or animals.

[0015] The molecular weight of the biomass-derived polyol that can be used in the present technology is not particularly limited as long as it does not impair the action and effect of the present technology, but it is preferable to use a biomass-derived polyol having a molecular weight of less than 1000 in combination with a biomass-derived polyol having a molecular weight of 1000 or more. By using a biomass-derived polyol having a molecular weight of less than 1000 in combination with a biomass-derived polyol having a molecular weight of 1000 or more, the slow recovery properties of the polyurethane foam produced can be improved.

[0016] When a biomass-derived polyol having a molecular weight of less than 1000 and a biomass-derived polyol having a molecular weight of 1000 or more are used in combination, the ratio thereof is not particularly limited, but it is preferable to use more of the biomass-derived polyol having a molecular weight of less than 1000 than the biomass-derived polyol having a molecular weight of 1000 or more. Specifically, the lower limit of the content of the biomass-derived polyol having a molecular weight of less than 1000 relative to the content of the biomass-derived polyol having a molecular weight of 1000 or more is, for example, 1.1 times or more, preferably 1.2 times or more, and more preferably 1.3 times or more. The upper limit of the content of the biomass-derived polyol having a molecular weight of less than 1000 relative to the content of the biomass-derived polyol having a molecular weight of 1000 or more is, for example, 2.0 times or less, preferably 1.9 times or less, and more preferably 1.8 times or less. By setting the upper limit of the content of the biomass-derived polyol having a molecular weight of less than 1000 within this range, it is possible to prevent the polyurethane foam produced from becoming too hard or from having a high glass transition temperature.

[0017] The content of biomass-derived polyol in the polyol component used in this technology can be freely set as long as it does not impair the action and effect of this technology. The lower limit of the content of biomass-derived polyol per 100 parts by mass of the polyol component used in this technology is, for example, 35 parts by mass or more, preferably 40 parts by mass or more, more preferably 45 parts by mass or more, even more preferably 50 parts by mass or more, still more preferably 55 parts by mass or more, and particularly preferably 60 parts by mass or more. In this technology, by setting the content of biomass-derived polyol in the polyol component within this range, the biomass content of the polyurethane foam produced can be improved, the environmental load can be further reduced, and a sustainable society can be further contributed to.

[0018] The upper limit of the content of biomass-derived polyol per 100 parts by mass of the polyol component used in the present technology is, for example, 95 parts by mass or less, preferably 90 parts by mass or less, more preferably 85 parts by mass or less, and even more preferably 80 parts by mass or less. In the present technology, by setting the content of biomass-derived polyol in the polyol component within this range, it is possible to suppress deterioration in the physical properties of the polyurethane foam produced.

[0019] (1-2) Polyols other than biomass-derived polyols In the present technology, polyols other than biomass-derived polyols can also be used in combination. Examples of polyols other than biomass-derived polyols include polyester polyols, polyether polyols, polyester ether polyols, polycarbonate polyols, and polymer polyols.

[0020] (1-2-1) Polyester Polyol Examples of polyester polyols include polylactone polyols and polycaprolactone polyols obtained by ring-opening polymerization of lactone monomers such as ε-caprolactone and methylvalerolactone; aliphatic dicarboxylic acids such as succinic acid, adipic acid, sebacic acid, and azelaic acid; aliphatic carboxylic acids such as ricinoleic acid; aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and naphthalenedicarboxylic acid; alicyclic dicarboxylic acids such as hexahydrophthalic acid, hexahydroterephthalic acid, and hexahydroisophthalic acid; Alternatively, polyester polyols such as polypropylene glycol obtained by a dehydration condensation reaction of these acid esters or acid anhydrides with ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, or the like, or a mixture thereof, can be mentioned. Among these, in the present technology, it is preferable to use polycaprolactone polyol, it is more preferable to use polycaprolactone diol or polycaprolactone triol, and it is even more preferable to use polycaprolactone diol and polycaprolactone triol in combination.

[0021] The number of functional groups of the polyester polyol that can be used in the present technology is not particularly limited as long as it does not impair the action and effect of the present technology, but it is preferable to use a polyester polyol having a functionality of less than 2.5 in combination with a polyester polyol having a functionality of 2.5 or more. By using a polyester polyol having a functionality of less than 2.5 in combination with a polyester polyol having a functionality of 2.5 or more, it is possible to adjust the balance of physical properties by achieving both elongation and flexibility and hardness of the polyurethane foam to be produced.

[0022] When a polyester polyol having a functionality of less than 2.5 is used in combination with a polyester polyol having a functionality of 2.5 or more, the ratio is not particularly limited, but it is preferable to use more of the polyester polyol having a functionality of less than 2.5 than the polyester polyol having a functionality of 2.5 or more. By increasing the amount of the polyester polyol having a functionality of less than 2.5, the initial reactivity during polyurethane foam production can be improved, the elongation of the polyurethane foam produced can be improved, and an excessive increase in hardness can be prevented, thereby preventing a decrease in slow recovery properties. Specifically, the lower limit of the content of the polyester polyol having a functionality of less than 2.5 relative to the content of the polyester polyol having a functionality of 2.5 or more is, for example, 1.5 times or more, preferably 2.0 times or more, and more preferably 2.5 times or more. The upper limit of the content of the polyester polyol having a functionality of less than 2.5 relative to the content of the polyester polyol having a functionality of 2.5 or more is, for example, 5.0 times or less, preferably 4.5 times or less, and more preferably 4.0 times or less.

[0023] When a polyester polyol is used as a polyol other than a biomass-derived polyol, its content can be freely set as long as it does not impair the action and effect of the present technology. The lower limit of the content of the polyester polyol per 100 parts by mass of the polyol component used in the present technology is, for example, 5 parts by mass or more, preferably 10 parts by mass or more, and more preferably 15 parts by mass or more. In the present technology, by setting the content of the polyester polyol in the polyol component within this range, the reactivity during polyurethane foam production can be improved, and the physical properties of the produced polyurethane foam can be further improved.

[0024] The upper limit of the content of polyester polyol per 100 parts by mass of the polyol component used in the present technology is, for example, 40 parts by mass or less, preferably 30 parts by mass or less, and more preferably 25 parts by mass or less. In the present technology, by setting the content of polyester polyol in the polyol component within this range, the biomass content of the polyurethane foam produced can be improved, the environmental load can be reduced, and this can further contribute to the creation of a sustainable society.

[0025] (1-2-2) Polyether Polyols Examples of polyether polyols include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, etc., which are obtained by polymerizing cyclic ethers such as ethylene oxide (EO), propylene oxide (PO), and tetrahydrofuran as an initiator, and copolyethers thereof. Polyether polyols can also be obtained by polymerizing the above-mentioned cyclic ethers using polyhydric alcohols such as glycerin and trimethylolethane.

[0026] The number of functional groups of the polyether polyol that can be used in the present technology is not particularly limited as long as it does not impair the action and effect of the present technology, but it is preferable to use a polyether polyol with three functional groups.

[0027] When a polyether polyol is used as a polyol other than a biomass-derived polyol, its content can be freely set as long as it does not impair the action and effect of the present technology. The lower limit of the content of polyether polyol per 100 parts by mass of the polyol component used in the present technology is, for example, 0.5 parts by mass or more, preferably 1.0 parts by mass or more, and more preferably 2.0 parts by mass or more. In the present technology, by setting the content of polyether polyol in the polyol component within this range, the flexibility of the produced polyurethane foam can be improved and the glass transition temperature can be further lowered.

[0028] The upper limit of the polyether polyol content per 100 parts by mass of the polyol component used in this technology is, for example, 15 parts by mass or less, preferably 10 parts by mass or less, and more preferably 7.0 parts by mass or less. By setting the polyether polyol content in the polyol component within this range, this technology can improve the biomass content of the polyurethane foam produced, reduce the environmental load, and further contribute to the creation of a sustainable society.

[0029] (1-2-3) Polyester Ether Polyol Examples of polyester ether polyols include those obtained by a dehydration condensation reaction of an aliphatic dicarboxylic acid such as succinic acid, adipic acid, sebacic acid, or azelaic acid; an aromatic dicarboxylic acid such as phthalic acid, terephthalic acid, isophthalic acid, or naphthalenedicarboxylic acid; an alicyclic dicarboxylic acid such as hexahydrophthalic acid, hexahydroterephthalic acid, or hexahydroisophthalic acid; or an acid ester or anhydride thereof with a glycol such as diethylene glycol or a propylene oxide adduct, or a mixture thereof.

[0030] (1-2-4) Polycarbonate Polyols Examples of polycarbonate polyols include those obtained by reacting at least one polyhydric alcohol such as ethylene glycol, 1,2-propylene glycol, 1,3-propylene glycol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, neopentyl glycol, 1,8-octanediol, 1,9-nonanediol, or diethylene glycol with diethylene carbonate, dimethyl carbonate, diethyl carbonate, or the like.

[0031] (1-2-5) Polymer Polyol Polymer polyols are those obtained by polymerizing an ethylenically unsaturated monomer in a polyol, or those obtained by emulsifying and dispersing a polymer of an ethylenically unsaturated monomer in a polyol, etc. Specific examples include those obtained by graft polymerizing acrylonitrile, styrene, etc. onto a polyol, and those obtained by dispersing polystyrene or polyacrylonitrile in a polyol.

[0032] (1-2-6) Biodegradable Polyols In consideration of the environment, biodegradable polyols can also be used in this technology. As the biodegradable polyol that can be used in this technology, one or more biodegradable polyols that can be used in the production of polyurethane foams can be freely selected and used, as long as the purpose and effects of the technology are not impaired. Examples of biodegradable polyols that can be used in this technology include polyglycolic acid (PGA), polylactic acid (PLA), polybutylene succinate (PBS), polybutylene succinate adipate (PBSA), polybutylene adipate terephthalate (PBAT), polycaprolactone (PCL), polyethylene glycol (PEG), polyvinyl alcohol (PVA), and polyhydroxyalkanoic acid (PHA).

[0033] (2) Isocyanate The isocyanate that can be used in the present technology can be freely selected from one or more isocyanates that can be used in the production of polyurethane foam, as long as it does not impair the purpose and effects of the present technology. Examples include aliphatic isocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, and dicyclohexylmethane diisocyanate; aromatic isocyanates such as toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), naphthalene diisocyanate, xylylene diisocyanate, and polymeric polyisocyanate; and modified polyisocyanates obtained by modifying these. Among these, in the present technology, it is preferable to use diphenylmethane diisocyanate (MDI) as the isocyanate, and it is more preferable to use polymeric MDI (crude MDI) or MDI-based prepolymers, and it is even more preferable to use polymeric MDI (crude MDI) and MDI-based prepolymers in combination.

[0034] The isocyanate index of the polyurethane foam is also not particularly limited as long as it does not impair the functions and effects of the present technology. In the present technology, the lower limit of the isocyanate index is, for example, 75 or more, preferably 80 or more, and more preferably 85 or more. By setting the lower limit of the isocyanate index within this range, it is possible to suppress deterioration of the compression set of the polyurethane foam produced, prevent sagging of the polyurethane foam, and improve cushioning performance.

[0035] The upper limit of the isocyanate index is, for example, not more than 95, preferably not more than 92, and more preferably not more than 91. By setting the upper limit of the isocyanate index within this range, the elongation percentage of the polyurethane foam can be improved, and the slow recovery property can also be improved.

[0036] In the present technology, the isocyanate index is a value calculated by [(isocyanate equivalent in the composition for producing polyurethane foam / active hydrogen equivalent in the composition for producing polyurethane foam)×100].

[0037] (3) Filler The filler that can be used in the present technology can be freely selected from one or more fillers that can be used in the production of polyurethane foam, as long as it does not impair the purpose and effects of the present technology. When producing polyurethane foam using the mechanical froth method, the filler also functions as a nucleating agent (foaming base point). Examples of fillers include metal hydroxides such as calcium carbonate, aluminum hydroxide, and magnesium hydroxide, alumina trihydrate, silica, talc, calcium carbonate, and clay. Among these, metal hydroxides are preferred as fillers in the present technology, and among metal hydroxides, aluminum hydroxide is more preferred.

[0038] The amount of filler in the composition used to produce the polyurethane foam according to the present technology can be freely set as long as it does not impair the function and effect of the present technology. In the present technology, the lower limit of the filler content in the composition is, for example, 1 part by mass or more, preferably 3 parts by mass or more, and more preferably 5 parts by mass or more, per 100 parts by mass of polyol. The upper limit of the filler content in the composition is, for example, 20 parts by mass or less, preferably 15 parts by mass or less, and more preferably 12 parts by mass or less, per 100 parts by mass of polyol.

[0039] (4) Catalyst A catalyst can be used in the production of polyurethane foam according to the present technology. As the catalyst that can be used in the present technology, one or more catalysts that can be used in the production of polyurethane foam can be freely selected and used, as long as the action and effect of the present technology are not impaired.

[0040] Examples of the catalyst include metal catalysts (organometallic catalysts) such as organic iron compounds (iron acetylacetonate, etc.), organic nickel compounds (nickel acetylacetonate, nickel octoate, nickel naphthenate, etc.), organic tin compounds (tin (II) octoate (tin 2-ethylhexanoate, stannous octoate, etc.), organic bismuth compounds (bismuth octoate, bismuth naphthenate, etc.), organic lead compounds (lead octoate, lead naphthenate, etc.), organic cobalt compounds (cobalt acetylacetonate, cobalt octoate, cobalt naphthenate, etc.), organic zirconium compounds (zirconium acetylacetonate, etc.), and organic zinc compounds; and organic compounds such as triethylamine, triethylenediamine (TEDA), tetramethylguanidine, diethanolamine, bis(2-dimethylaminoethyl)ether, N,N,N Examples of amine catalysts include amines such as N',N",N"-pentamethyldiethylenetriamine, imidazole-based compounds, piperazine-based amines such as dimethylpiperazine, N-methyl-N'-(2-dimethylamino)ethylpiperazine, and N-methyl-N'-(2-hydroxyethyl)piperazine, morpholine-based amines such as N-methylmorpholine and N-ethylmorpholine, and amines known as DBU homologues such as 1,8-diazabicyclo-[5,4,0]-undecene-7 (DBU), 1,5-diazabicyclo-[4,3,0]-nonene-5 (DBN), 1,8-diazabicyclo-[5,3,0]-decene-7 (DBD), and 1,4-diazabicyclo-[3,3,0]octene-4 (DBO). Among these, in the present technology, it is preferable to use an organic iron compound, and it is more preferable to use iron acetylacetonate.

[0041] The amount of catalyst in the composition used to produce the polyurethane foam according to the present technology can be freely set as long as it does not impair the function and effect of the present technology. In the present technology, the lower limit of the catalyst content in the composition is, for example, 0.1 parts by mass or more, preferably 0.5 parts by mass or more, and more preferably 1.0 parts by mass or more, per 100 parts by mass of polyol. By setting the lower limit of the catalyst content in the composition within this range, various reactions during production can be controlled, and as a result, polyurethane foam with excellent mechanical properties and appearance can be obtained.

[0042] In this technology, the upper limit of the catalyst content in the composition is, for example, 10 parts by mass or less, preferably 8 parts by mass or less, and more preferably 6 parts by mass or less, per 100 parts by mass of polyol. By setting the upper limit of the catalyst content in the composition within this range, it is possible to prevent destabilization of various reactions during production. As a result, a polyurethane foam with excellent mechanical properties and appearance can be obtained.

[0043] (5) Antioxidant An antioxidant can be used in the production of polyurethane foam according to the present technology. As the antioxidant that can be used in the present technology, one or more antioxidants that can be used in the production of polyurethane foam can be freely selected and used, as long as the action and effect of the present technology are not impaired. For example, one or more antioxidants can be freely combined and used from phenol-based (monophenol-based, thiobisphenol-based, hindered phenol-based), naphthylamine-based, diphenylamine-based, p-phenyldiamine-based, quinoline-based, hydroquinone derivatives, phosphite ester-based, etc. Among these, in the present technology, it is preferable to use a phenol-based antioxidant as the antioxidant.

[0044] The amount of antioxidant in the composition used to produce the polyurethane foam according to the present technology can be freely set as long as it does not impair the function and effect of the present technology. In the present technology, the lower limit of the content of the antioxidant in the composition is, for example, 0.01 parts by mass or more, preferably 0.03 parts by mass or more, and more preferably 0.05 parts by mass or more, per 100 parts by mass of polyol. By setting the lower limit of the content of the antioxidant in the composition within this range, the effect of preventing discoloration by preventing scorch can be improved.

[0045] In the present technology, the upper limit of the content of the antioxidant in the composition is, for example, 5 parts by mass or less, preferably 3 parts by mass or less, and more preferably 1 part by mass or less, relative to 100 parts by mass of the polyol. Setting the upper limit of the content of the antioxidant in the composition within this range can contribute to cost reduction.

[0046] (6) Moisture absorbent A moisture absorbent can be used in the production of polyurethane foam according to the present technology. The use of a moisture absorbent can prevent unintended foaming due to moisture contained in the reaction atmosphere or materials. It is particularly preferable to use a moisture absorbent when producing polyurethane foam by the mechanical froth method. As the moisture absorbent that can be used in the present technology, one or more moisture absorbents that can be used in polyurethane foam can be freely selected and used, as long as they do not impair the action and effect of the present technology. Examples of moisture absorbents include zeolite, silica gel, calcium oxide, activated carbon, potassium hydroxide, sodium hydroxide, and lithium hydroxide. Among these, it is preferable to use zeolite as the moisture absorbent in the present technology.

[0047] The amount of moisture absorbent in the composition used to produce polyurethane foam according to the present technology can be freely set as long as it does not impair the function and effect of the present technology. In the present technology, the lower limit of the content of the moisture absorbent in the composition is, for example, 0.1 parts by mass or more, preferably 0.5 parts by mass or more, and more preferably 1.0 parts by mass or more, per 100 parts by mass of polyol. The upper limit of the content of the moisture absorbent in the composition is, for example, 10 parts by mass or less, preferably 7 parts by mass or less, and more preferably 5 parts by mass or less, per 100 parts by mass of polyol.

[0048] (7) Foam Stabilizer A foam stabilizer can be used in the production of polyurethane foam according to the present technology. By using a foam stabilizer, a better quality polyurethane foam can be produced.

[0049] As the foam stabilizer that can be used in the present technology, one or more foam stabilizers that can be used in the production of polyurethane foam can be freely selected and used, as long as the action and effect of the present technology are not impaired. Examples include silicone-based foam stabilizers, fluorine-containing compound-based foam stabilizers, surfactants, etc. Examples of silicone-based foam stabilizers include those mainly composed of siloxane chains, those in which the siloxane chain and polyether chain have a linear structure, those that are branched, and those in which the polyether chain is modified to have a pendant shape on the siloxane chain. Among these, in the present technology, it is preferable to use a silicone-based foam stabilizer as the foam stabilizer.

[0050] The amount of foam stabilizer in the composition used to produce the polyurethane foam according to the present technology can be freely set as long as it does not impair the action and effect of the present technology. The lower limit of the content of the foam stabilizer in the composition is, for example, 1 part by mass or more, preferably 3 parts by mass or more, and more preferably 5 parts by mass or more, per 100 parts by mass of polyol. The upper limit of the content of the moisture absorbent in the composition is, for example, 20 parts by mass or less, preferably 15 parts by mass or less, and more preferably 12 parts by mass or less, per 100 parts by mass of polyol.

[0051] (8) Foam-forming gas A foam-forming gas can be used in the production of polyurethane foam according to the present technology. As the foam-forming gas that can be used in the present technology, one or more foam-forming gases that can be used in the production of polyurethane foam can be freely selected and used, as long as the action and effect of the present technology are not impaired.

[0052] Examples of foam-forming gases include dry air and inert gases such as nitrogen. The mixing ratio of the foam-forming gas with other raw materials can be freely set depending on the application of the polyurethane foam to be produced, as long as it does not impair the purpose and effects of the present technology. In the present technology, the mixing ratio of the foam-forming gas with other raw materials can be set to, for example, 10% by volume or more, preferably 15% by volume or more, and more preferably 20% by volume or more, based on 100% by volume of the foam-forming gas and other raw materials combined.

[0053] In this technology, the upper limit of the mixing ratio of the foam-forming gas with other raw materials can be set to, for example, 100 volume % or less, 95 volume % or less, or 90 volume % or less out of 100 volume % of the foam-forming gas and other raw materials combined.

[0054] (9) Blowing Agent The polyurethane foam according to the present technology can be produced by a mechanical froth method, as described below, and in that case, the polyurethane foam according to the present technology can be produced without a blowing agent, but the present technology also allows the use of a blowing agent. As the blowing agent that can be used in the present technology, one or more blowing agents that can be used in the production of polyurethane foam can be freely selected and used, as long as the purpose and effects of the present technology are not impaired.

[0055] The foaming agent usable in the present technology may be either a chemical foaming agent or a physical foaming agent. Examples of chemical foaming agents include reactive foaming agents that generate carbon dioxide gas by reacting with the isocyanates described above, such as water or carboxylic acids such as formic acid and acetic acid, and generate foaming. Physical foaming agents such as volatile hydrocarbons, and organic or inorganic thermal decomposition chemical foaming agents are also available. Examples of inorganic foaming agents include sodium bicarbonate, ammonium carbonate, sodium carbonate, ammonium bicarbonate, ammonium nitrite, sodium borohydride, and anhydrous monosodium citrate.

[0056] Examples of physical blowing agents include fluorocarbons such as hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs), hydrofluoroolefins (HFOs), hydrocarbons such as heptane, hexane, pentane, and cyclopentane, and carbon dioxide.

[0057] The amount of blowing agent in the composition used to produce the polyurethane foam according to the present technology can be freely set as long as it does not impair the function and effect of the present technology. In the present technology, the content of the blowing agent in the composition is, for example, 10 parts by mass or less, preferably 7 parts by mass or less, and more preferably 5 parts by mass or less, per 100 parts by mass of polyol. By setting the upper limit of the blowing agent content in this range, it is possible to suppress formation defects due to excessive foaming and also contribute to cost reduction.

[0058] (10) Others In the production of polyurethane foam according to the present technology, one or more of various components that can be used in the production of polyurethane foam can be freely selected and used as other components depending on the purpose, as long as the action and effect of the present technology are not impaired.

[0059] Examples of components that can be used in producing polyurethane foams according to the present technology include flame retardants, pigments, stabilizers, plasticizers, colorants, crosslinking agents, antibacterial agents, dispersants, and ultraviolet absorbers.

[0060] 2. Polyurethane Foam The polyurethane foam according to the present technology can be produced using the composition described above.

[0061] (1) Biomass ratio As demonstrated in the examples described below, the present technology can produce high-quality polyurethane foams even when using biomass-derived polyols, thereby improving the biomass ratio of the produced polyurethane foam and contributing to environmental conservation and the creation of a sustainable society. The biomass ratio of the polyurethane foam according to the present technology can be, for example, 20% or more, preferably 25% or more, and more preferably 30% or more.

[0062] In this technology, the biomass degree is a value calculated using the following formula: Biomass degree (%) = {(Weight of biomass material × Biomass degree of biomass material / 100) / Total weight of raw materials} × 100

[0063] (2) Density The polyurethane foam according to the present invention has a density of 120 kg / m 3The polyurethane foam according to the present technology is characterized in that its density is 120 kg / m or more. 3 Due to the above, the composition can be suitably used as a cushioning material for absorbing vibrations and shocks in electronic devices such as mobile phones, cameras, and televisions, and electrical devices such as home appliances, as a sealing material for various batteries, as a sealing material for the periphery of batteries and electronic control units in electric vehicles, as a heat insulating material, and the like.

[0064] The density of the polyurethane foam according to this technology is 120 kg / m 3 If the load is more than 130 kg / m, the effect of this technology can be achieved. 3 More preferably, it is 140 kg / m or more. 3 More preferably, it is 150 kg / m or more. 3 It is even more preferable that the value is 160 kg / m or more. 3 More preferably, it is equal to or greater than this.

[0065] The upper limit of the density of the polyurethane foam according to the present technology can be freely set as long as it does not impair the purpose and effect of the present technology. For example, 3 Preferably 900 kg / m or less 3 or less, more preferably 800 kg / m 3 More preferably, 700 kg / m or less 3 By setting the density of the polyurethane foam within this range, it is possible to impart cushioning properties without impairing the flexibility of the polyurethane foam (preventing it from becoming hard).

[0066] In the present technology, the density is a value measured by a method conforming to JIS K6401:2011.

[0067] (3) Elongation The elongation of the polyurethane foam according to the present technology can be freely set as long as it does not impair the function and effect of the present technology. The lower limit of the elongation of the polyurethane foam according to the present technology is, for example, 200% or more, preferably 210% or more, more preferably 220% or more, and even more preferably 230% or more. The upper limit of the elongation of the polyurethane foam according to the present technology is, for example, 1000% or less, 900% or less, or 800% or less.

[0068] In the present technology, the elongation is a value measured by a method conforming to JIS K6251:2010.

[0069] (4) Glass Transition Point The glass transition point of the polyurethane foam according to the present technology can be freely set as long as it does not impair the functions and effects of the present technology. The glass transition point of the polyurethane foam according to the present technology is, for example, 5°C or lower, preferably 0°C or lower, more preferably -5°C or lower, even more preferably -10°C or lower, still more preferably -12°C or lower, and particularly preferably -15°C or lower.

[0070] In the present technology, the glass transition temperature is a value measured by the method described in the examples below.

[0071] (5) Storage Modulus The polyurethane foam according to the present technology is characterized by a small change in storage modulus due to temperature change. Specifically, the polyurethane foam according to the present technology has a small change in storage modulus due to temperature change in the usage environment of −10°C to 30°C.

[0072] The specific value of the storage modulus is not particularly limited, but the difference in storage modulus in the temperature range of −10° C. to 30° C. (LOG (storage modulus at −10° C.) − LOG (storage modulus at 30° C.)) is, for example, preferably 2.0 MPa or less, more preferably 1.5 MPa or less, and even more preferably 1.0 MPa or less.

[0073] (6) Return Speed ​​The return speed of the polyurethane foam according to the present technology can be freely set as long as it does not impair the action and effect of the present technology. The return speed of the polyurethane foam according to the present technology is, for example, 1 second or more, preferably 2 seconds or more, and more preferably 3 seconds or more.

[0074] In the present technology, the return speed is a value measured by the method described in the examples below.

[0075] (7) Thickness The thickness of the polyurethane foam according to the present technology can be freely set as long as it does not impair the purpose and effect of the present technology. However, the polyurethane foam according to the present technology has excellent slow recovery properties even when its thickness is 10 mm or less.

[0076] The lower limit of the thickness of the polyurethane foam according to the present technology can be freely set as long as it does not impair the purpose and effects of the present technology, but is, for example, 0.05 mm or more, preferably 0.1 mm or more, and more preferably 0.2 mm or more. By setting the thickness of the polyurethane foam within this range, it is possible to exhibit better slow recovery properties.

[0077] The upper limit of the thickness of the polyurethane foam according to the present technology can be freely set as long as it does not impair the purpose and effect of the present technology, but is, for example, 10 mm or less, preferably 7.0 mm or less, and more preferably 5.0 mm or less.

[0078] (8) Applications Taking advantage of its high quality, the polyurethane foam according to the present technology can be used for a wide variety of applications in a wide variety of fields. For example, it can be suitably used for furniture such as sofas and chairs, bedding such as mattresses and pillows, clothing such as underwear, daily necessities such as tableware and cleaning sponges, vehicle and aircraft interior products such as car seats, construction joint materials, construction cushioning materials, construction sealants, home appliance sealants, electrical equipment cushioning materials, electronic equipment cushioning materials, electrical equipment sealants, electronic equipment sealants, various battery sealants, soundproofing materials, packaging materials, vehicle insulation materials, vehicle battery sealants, vehicle electronic control unit sealants, anti-condensation materials, interior materials, home appliance insulation materials, pipe insulation materials, various covers, cushioning materials, toys, miscellaneous goods, etc.

[0079] 3. Method for Producing Polyurethane Foam The polyurethane foam according to the present technology can be produced by mixing the components of the composition described above to prepare a composition, and foaming the prepared composition by a known method. Specific methods for the composition preparation step, foaming step, etc. can be freely combined with conventional methods as long as they do not impair the functions and effects of the present technology.

[0080] In the method for producing polyurethane foam according to the present technology, it is particularly preferable to use a mechanical froth method. By using the mechanical froth method, it is easier to adjust the density compared to chemical foaming methods, and high-density polyurethane foam can be produced. It is also possible to produce thin polyurethane foam.

[0081] As a specific method for the mechanical froth method, a general mechanical froth method can be used as long as it does not impair the functions and effects of the present technology. For example, the raw materials of the above-mentioned composition other than the isocyanate and foam-forming gas are charged into a mixing head and mixed at a timing appropriate for the type and purpose of each raw material to prepare an intermediate composition. The isocyanate is charged into the prepared intermediate composition, and while mixing, the foam-forming gas is mixed in, and the mixture is stirred and mixed to become homogeneous. Then, the mixture is heated and cured on release paper or in a mold, whereby a polyurethane foam can be produced.

[0082] The present technology can have the following configurations: [1] A biomass-derived polyol is contained as a polyol component, and the density is 120 kg / m 3 [2] A polyurethane foam according to [1], having an elongation of 200% or more as measured in accordance with JIS K6401:2011. [3] A polyurethane foam according to [1], containing a biomass-derived polyol as a polyol component, having a density of 120 kg / m 3[4] The polyurethane foam according to [3], having an isocyanate index of 92 or less. [5] The polyurethane foam according to any one of [1] to [4], having a glass transition temperature of 5°C or less. [6] The polyurethane foam according to any one of [1] to [5], having a biomass content of 20% or more. [7] A cushioning material, a sealing material, or a heat insulating material using the polyurethane foam according to any one of [1] to [6]. [8] A method for producing a polyurethane foam having a density of 120 kg / m, comprising the step of mixing a polyol component containing a biomass-derived polyol, an isocyanate, and a gas. 3 [9] A method for producing a polyurethane foam having a density of 120 kg / m or more and an isocyanate index of 92 or less, the method comprising the step of mixing a polyol component containing a biomass-derived polyol, an isocyanate, and a gas. 3 or more, and the elongation measured in accordance with JIS K6401:2011 is 200% or more.

[0083] The present technology will be described in more detail below based on examples. Note that the examples described below are examples of typical examples of the present technology, and the scope of the present technology should not be construed as being narrow.

[0084] (1) Production of Polyurethane Foam The components shown in Table 1 below were prepared in the blending ratios shown in Table 1 below to obtain mixed raw materials for each Example and Comparative Example. The mixed raw materials were then charged into a mixing head and stirred to a homogeneous mixture while mixing in a foam-forming gas (inert gas: nitrogen). The mixed raw materials were then applied to a continuously supplied PET film to a thickness of 3.0 mm and heat-cured at 200°C to produce sheet-like polyurethane foams.

[0085] (2) Measurement and Evaluation of Physical Properties [Biomass Degree] The biomass degree was calculated using the following formula: Biomass degree (%) = {(Weight of biomass material × Biomass degree of biomass material / 100) / Total weight of raw materials} × 100

[0086] [Density] The density was measured by a method in accordance with JIS K6401:2011.

[0087] [25% Compression Hardness] The 25% compression hardness was measured by a method in accordance with JIS K6254:2010.

[0088] [Tensile Strength] The tensile strength was measured by a method in accordance with JIS K6251:2010.

[0089] [Elongation] The elongation was measured by a method in accordance with JIS K6251:2010.

[0090] [Compression Set] Compression set was measured by a method in accordance with JIS K6401:2011.

[0091] [Glass transition point] [Storage modulus] Testing machine: Using an ARES-G2 rheometer manufactured by TA Instruments, the difference in storage modulus in the temperature range of -10°C to 30°C and the temperature at the peak of tan δ (glass transition point) were measured under the conditions of a temperature range of -40°C to 80°C (heating rate: 3°C / min), a mode: parallel plate mode (φ8 mm), a strain: 0.5%, and a frequency: 1.0 Hz.

[0092] [Return speed] [Slow recovery property] A load of 1 kg (compression surface: φ15 mm) was applied to each sample for 5 seconds using a constant pressure loader (manufactured by ASKER, CL-150). After that, the load was released and the return speed was measured. For the slow recovery property, a return speed of 2 seconds or more was evaluated as ○, and a return speed of less than 2 seconds was evaluated as ×.

[0093] (3) Results The results are shown in Table 1 below.

[0094] (4) Discussion As shown in Table 1, the polyurethane foams of Examples 1 to 6, which had an isocyanate index of 92 or less or an elongation of 200% or more, had good return speeds and excellent slow recovery properties despite the use of a biomass-derived polyol. On the other hand, the polyurethane foams of Comparative Examples 1 and 2 used a large amount of low-molecular-weight ether polyol 2 as the ether polyol to ensure slow recovery properties (due to the high ratio of low-molecular-weight polyol), resulting in a higher glass transition temperature (9.1°C) and a large change in hardness in the operating environment (temperature range of -10°C to 30°C). Furthermore, the polyurethane foams of Comparative Examples 3 and 4, which used a biomass-derived polyol, had an isocyanate index of more than 92, an elongation of less than 200%, and had a return speed of 0 and did not have slow recovery properties. The polyurethane foam of Example 2 was characterized by a low glass transition temperature (-18.7°C) and small change in hardness in the operating environment (temperature range of -10°C to 30°C).

Claims

1. Contains biomass-derived polyol as a polyol component and has a density of 120 kg / m 3 or more, and having an isocyanate index of 92 or less.

2. Contains biomass-derived polyol as a polyol component and has a density of 120 kg / m 3 or more, and has an elongation of 200% or more as measured in accordance with JIS K6401:2011.

3. The polyurethane foam according to claim 1 or 2, having a glass transition point of 5°C or lower.

4. The polyurethane foam according to claim 1 or 2, having a biomass content of 20% or more.

5. A cushioning material, a sealing material, or a heat insulating material, in which the polyurethane foam according to claim 1 or 2 is used.

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