CN114514273B

CN114514273B - Polyurethane foam, molded article thereof, and method for producing molded article

Info

Publication number: CN114514273B
Application number: CN202080071124.2A
Authority: CN
Inventors: 桐山卓也; 内田健斗
Original assignee: Logis Co ltd; Inoac Corp
Current assignee: Logis Co ltd; Inoac Corp
Priority date: 2019-10-10
Filing date: 2020-10-09
Publication date: 2023-07-25
Anticipated expiration: 2040-10-09
Also published as: JP2021185217A; CN114514273A

Abstract

A polyurethane foam obtained by a mechanical foaming method from a polyurethane reaction composition containing a polyol component containing a polymer polyol having a solid content of 20 to 43% by weight, a foam stabilizer, a catalyst and an isocyanate component, and an inert gas, wherein the polyurethane reaction composition contains an acid-modified polyolefin powder.

Description

Polyurethane foam, molded article thereof, and method for producing molded article

Technical Field

The present invention relates to a polyurethane foam suitable for thermal compression molding, a molded article thereof, and a method for producing the molded article.

Background

Thermoplastic resins can be shaped by heating, but have a problem of poor strain characteristics (large strain).

On the other hand, thermosetting resins can be molded by preliminary working using a mold, and have an advantage of good strain characteristics (low strain) although the post working is difficult.

Further, the conventional polyurethane foam can be subjected to hot compression molding at a high temperature, but has a problem in that it is difficult to say that the strain characteristics are good.

Prior art literature

Patent literature

Patent document 1: japanese patent laid-open No. 2009-013330 4

Disclosure of Invention

Problems to be solved by the invention

The present invention has been made in view of the above-described problems, and an object thereof is to provide a polyurethane foam which can be hot-compression molded and has excellent strain characteristics, a molded article thereof, and a method for producing the molded article.

Means for solving the problems

A polyurethane foam according to one aspect of the present invention which can solve the above problems,

(1) The polyurethane foam is obtained by a mechanical foaming method from a polyurethane reaction composition containing a polyol component containing a polymer polyol having a solid content of 20 to 43% by weight, a foam stabilizer, a catalyst and an isocyanate component, and an inert gas, and the polyurethane reaction composition contains an acid-modified polyolefin powder.

(2) In the polyurethane foam of the above (1), the acid-modified polyolefin powder is preferably a polyolefin powder modified with maleic anhydride.

(3) In the polyurethane foam of the above (1) or (2), the ratio of the total weight of the solid component of the polymer polyol and the acid-modified polyolefin powder to the weight of the polyurethane reaction composition is preferably 4 to 40% by weight.

(4) In the polyurethane foam according to any one of the above (1) to (3), it is preferable that the polyurethane foam is based on JIS K6401:2011 is 10% or less.

(5) A molded article of a polyurethane foam according to one aspect of the present invention, which can solve the above-mentioned problems, is a molded article comprising a sheet of a polyurethane foam, the sheet of the polyurethane foam having irregularities formed thereon by hot press molding, wherein the polyurethane foam is the polyurethane foam according to any one of the above (1) to (4).

(6) A method for producing a molded article according to one aspect of the present invention, which can solve the above-described problems, is a method for producing a molded article having irregularities formed by thermal compression molding on a surface of a sheet of a polyurethane foam, wherein the sheet of the polyurethane foam described in any one of (1) to (4) is preheated at 160 to 210 ℃ and subjected to thermal compression molding, and the preheated sheet is compressed and pressed using a normal temperature mold having irregularities on a mold surface, and the irregularities on the mold surface are formed on the surface of the sheet.

(7) In the method for producing a molded article according to (6), the sheet preferably has a compression ratio of 25 to 75% in the compression molding.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the polyurethane foam of the present invention, the polyurethane reaction composition contains 20 to 43% by weight of the polymer polyol and the acid-modified polyolefin powder as solid components, whereby the polyurethane foam can be thermoplastically deformed at a temperature equal to or lower than the decomposition temperature of the polyurethane bond, and the shape at the time of thermal compression molding can be maintained while the strain characteristics are good.

According to the molded article of the polyurethane foam of the present invention, a sheet-like molded article having excellent strain characteristics can be obtained, and the sheet-like molded article can maintain irregularities on the surface molded by thermal compression molding.

According to the method for producing a molded article of the present invention, a sheet comprising the polyurethane foam of the present invention is preheated at 160 to 210 ℃ and subjected to thermal compression molding, and the preheated sheet is compression molded using a normal temperature mold having a concave-convex surface provided on the surface of the mold, whereby a molded article having excellent strain characteristics can be obtained, which can maintain the concave-convex surface of the sheet molded by thermal compression molding, has a surface state free from surface burn and excellent in roughness, and has excellent molding retention (moldability).

Drawings

Fig. 1 is a plan view showing an embodiment of a molded body of a polyurethane foam.

Fig. 2 is a sectional view showing a section 2-2 of fig. 1.

Fig. 3 is a table showing the values and evaluations of the blending, the forming retention, the 25% cld, and the compressive residual strain of a part of the examples and the comparative examples.

Fig. 4 is a table showing the values and evaluations of the fit, shape retention, 25% cld, and compressive residual strain for the remaining examples.

Fig. 5 is a table showing examples and comparative examples in which the preheating temperature and the preheating time are varied.

Detailed Description

Embodiments of the polyurethane foam of the present invention will be described. The polyurethane foam of the present embodiment is obtained from a polyurethane reaction composition and an inert gas by a mechanical foaming method.

The mechanical foaming method is a method of forming a polyurethane foam by supplying a mixed raw material, which is mixed with a polyurethane reaction composition by compressing an inert gas, to an Oakes Mixer or a nozzle having a reduced tip, and discharging the mixed raw material from the Oakes Mixer or the nozzle. In the mechanical foaming method, when the mixed raw material is discharged, the inert gas compressed before that is expanded to form bubbles, and in this state, the polyol component reacts with the isocyanate component and is cured, thereby forming a polyurethane foam. In a polyurethane foam using an inert gas as a foaming functional agent (foaming agent) of a polyurethane reaction composition, the inert gas is contained in cells of the polyurethane foam.

The polyurethane reaction composition comprises a polyol component, a foam stabilizer, a catalyst, and an isocyanate component, and in this embodiment comprises an acid modified polyolefin powder. Further, as a foaming functional agent (foaming agent), an inert gas is contained as a mixed raw material.

The polyol component may contain a polyol other than the polymer polyol together with the polymer polyol.

Examples of the polymer polyol include polymer polyols obtained by graft polymerizing acrylonitrile, styrene, and the like with polyether polyols. The polymer polyol is preferably a polymer polyol having a molecular weight of 2000 to 5000, a functional group number of 2 to 4, a solid content of acrylonitrile, styrene or the like in the polymer polyol of 18 to 50% by weight (wt%), more preferably a polymer polyol having a solid content of 20 to 44% by weight (wt%), and particularly preferably a polymer polyol having a solid content of 20 to 43% by weight (wt). The polymer polyol may be used in combination of two or more. By including the polymer polyol in the polyol component, strain characteristics can be improved.

The content of the polymer polyol in the polyurethane reaction composition is preferably 3 to 40% by weight. If the content of the polymer polyol is small, a proper hardness is not obtained, whereas if it is large, the viscosity of the polyurethane reaction composition excessively increases, and foaming by mechanical foaming is not easy. The solid content of the polymer polyol in the polyurethane reaction composition is preferably 1 to 13% by weight. If the solid content of the polymer polyol is small, the heat forming is difficult, and the molding retention is poor, whereas if it is large, the heat forming is easy, but the viscosity of the polymer polyol may excessively rise, and the handling is difficult.

As the polyol other than the polymer polyol, a known polyol such as polyether polyol, polyester polyol and the like can be used. The polyether polyol preferably has a molecular weight of 300 to 5000 and a functional group number of 2 to 4, and the polyester polyol preferably has a molecular weight of 300 to 3000 and a functional group number of 2 to 4. Polyols other than the polymer polyol may be used in combination of two or more.

As the foam stabilizer, a foam stabilizer known for polyurethane foam can be used. Examples thereof include silicone foam stabilizers, fluorine foam stabilizers, and known surfactants. The amount of the foam stabilizer may be appropriately determined, and examples thereof include an amount of 1.0 to 6.0 parts by weight per 100 parts by weight of the polyol component.

As the catalyst, an amine-based catalyst and an organometallic catalyst for polyurethane foam are used singly or in combination. Examples of the amine-based catalyst include monoamine compounds, diamine compounds, triamine compounds, polyamine compounds, cyclic amine compounds, alcohol amine compounds, ether amine compounds, and the like, and 1 or 2 or more of them may be used in combination. Examples of the organometallic catalyst include organotin compounds, organoiron compounds, organobismuth compounds, organolead compounds, organozinc compounds, and the like, and 1 or 2 or more of them may be used. The amount of the catalyst may be appropriately determined, and examples thereof include an amount of 0.01 to 3.0 parts by weight per 100 parts by weight of the polyol component.

The isocyanate component may be any of aromatic, alicyclic and aliphatic isocyanates, may be a 2-functional isocyanate having 2 isocyanate groups in 1 molecule, or may be a 3-functional or more isocyanate having 3 or more isocyanate groups in 1 molecule, and may be used alone or in combination of two or more.

Examples of the 2-functional isocyanate include aromatic isocyanates such as 2, 4-Toluene Diisocyanate (TDI), 2, 6-Toluene Diisocyanate (TDI), m-phenylene diisocyanate, p-phenylene diisocyanate, 4 '-diphenylmethane diisocyanate (MDI), 2' -diphenylmethane diisocyanate (MDI), xylylene diisocyanate, 3 '-dimethyl-4, 4' -biphenyl diisocyanate, and 3,3 '-dimethoxy-4, 4' -biphenyl diisocyanate; alicyclic isocyanates such as cyclohexane-1, 4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4, 4' -diisocyanate, methylcyclohexane diisocyanate, and the like; aliphatic isocyanates such as butane-1, 4-diisocyanate, hexamethylene diisocyanate, isopropenyl diisocyanate, methylene diisocyanate and lysine isocyanate.

Further, as the isocyanate having 2 or more functions, polymethylene polyphenyl isocyanate (polymeric MDI) is exemplified. Examples of the isocyanate having 3 or more functions include 1-methylbenzene-2, 4, 6-triisocyanate, 1,3, 5-trimethylbenzene-2, 4, 6-triisocyanate, biphenyl-2, 4' -triisocyanate, diphenylmethane-2, 4' -triisocyanate, methyldiphenylmethane-4, 6,4' -triisocyanate, 4' -dimethyldiphenylmethane-2, 2', 5' tetraisocyanate, triphenylmethane-4, 4',4 "-triisocyanate and the like. The isocyanate is not limited to one type, and may be one or more types. For example, one aliphatic isocyanate and two aromatic isocyanates may be used in combination. The isocyanate index is preferably from 90 to 110. The isocyanate index is a value obtained by multiplying the number of moles of isocyanate groups by 100 times the number of moles of active hydrogen groups contained in the urethane raw material, and is calculated by [ (equivalent of isocyanate in the foam raw material/equivalent of active hydrogen in the foam raw material) ×100 ].

Examples of the acid-modified polyolefin powder include a powder of an acid-modified polyolefin modified with an acid of an unsaturated carboxylic acid or an acid anhydride thereof, such as Polyethylene (PE), polypropylene (PP), polybutene (PB), polypentene, an ethylene-propylene copolymer, an ethylene-vinyl acetate copolymer, and a styrene-ethylene/butene-styrene block copolymer (SEBS).

Among the acid-modified polyolefin, acid-modified polyolefin modified with maleic anhydride is preferable. Examples of the acid-modified polyolefin modified with maleic anhydride include maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, and maleic anhydride-modified ethylene-propylene copolymer. The maleic anhydride-modified polypropylene includes a polypropylene modified with maleic anhydride as a random copolymer with ethylene, and the maleic anhydride-modified ethylene-propylene copolymer includes a maleic anhydride-modified ethylene-propylene copolymer modified with maleic anhydride as a polypropylene as a so-called block copolymer copolymerizing ethylene and propylene. In particular, maleic anhydride-modified polyethylene and maleic anhydride-modified polypropylene are preferable because they have better molding retention than other acid-modified polyolefin. The acid-modified polyolefin powder is not limited to one, and may contain a plurality of kinds. The powder is a powder having a particle diameter of 5 to 250. Mu.m. The melting point of the acid-modified polyolefin may be 80 to 165 ℃, preferably 90 to 140 ℃.

By incorporating the acid-modified polyolefin powder into the polyurethane reaction composition together with the polymer polyol, it is possible to preheat the polyurethane foam at a temperature higher than the melting point of the acid-modified polyolefin powder, and to thermoplastically deform the polyurethane foam at or below the decomposition temperature of the urethane bond (thermal compression molding), and the strain characteristics are good.

The content of the acid-modified polyolefin powder in the polyurethane reaction composition is preferably 3 to 35% by weight. If the content of the acid-modified polyolefin powder is small, the heat forming cannot be performed, whereas if it is large, the foaming cannot be performed by mechanical foaming due to the increase in viscosity.

The ratio of the total weight (total resin amount) of the solid component of the polymer polyol and the acid-modified polyolefin powder to the weight of the polyurethane reaction composition is preferably 4 to 40% by weight, more preferably 10 to 40% by weight. If the total weight (total resin amount) of the solid component of the polymer polyol and the acid-modified polyolefin powder is small, thermoforming is not performed, and the molding retention is also low. In contrast, if the total resin amount becomes large, the viscosity of the polyurethane reaction composition excessively increases and foaming by mechanical foaming is not possible.

In addition, any additive may be added to the polyurethane reaction composition. Examples of the optional additives include a crosslinking agent, a filler, a dye, a pigment, an antioxidant, and a flame retardant.

Examples of the crosslinking agent include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1, 4-butanediol, and 1, 6-hexanediol.

Examples of the filler include alumina trihydrate, silica, talc, calcium carbonate, clay, and the like.

As the inert gas used as the foaming functional agent (foaming agent), a gas which does not adversely affect the reaction of the polyol with isocyanate or the like, for example, dry air, nitrogen gas or the like is preferable. The inert gas is preferably mixed in the polyurethane reaction composition in a proportion of 31 to 91% by volume. The mixing ratio of the inert gas is the volume% of the foam-forming gas relative to 100 parts by volume of the polyurethane reaction composition excluding the inert gas.

The polyurethane foam of the present embodiment has a compressive residual strain (JIS K6401:2011) of 10% or less, and undergoes little plastic deformation over a long period of time.

The polyurethane foam of the present embodiment is preferably subjected to a 25% compression load (25%CLD,JIS K6254:2010, toCompressive stress at 25% compression at a rate of 1 mm/min) is 0.01 to 0.1MPa.

The molded article of the polyurethane foam of the present embodiment is produced by molding irregularities by thermal compression molding including preheating the polyurethane foam and compression molding by a room temperature mold. The thermal compression molding is performed by preheating the polyurethane foam at 160 to 210 ℃, more preferably at 190 to 210 ℃, and compression-molding by a mold at ordinary temperature (20 to 35 ℃). The preheating time is preferably 3 to 10 minutes. The surface of the mold is provided with irregularities corresponding to the use of the molded article, so that the surface of the molded article is provided with irregularities. The compression ratio at the time of compression pressurization is preferably 25 to 75%. In addition, the compression ratio was calculated by compression ratio= [ (original thickness-thickness at the time of compression)/original thickness×100 ].

Fig. 1 and 2 show an example of a molded article of polyurethane foam. The polyurethane foam molded body 10 shown in fig. 1 and 2 is obtained by preheating a sheet of the polyurethane foam of the present embodiment formed of a predetermined thickness at 200 ℃ for 5 minutes, and subjecting the preheated sheet to compression molding at normal temperature (25 ℃) to thereby form irregularities, and the polyurethane foam molded body 10 is used as an insole. The molded article 10 of the polyurethane foam has concave portions 101 and 103 and convex portions 102, 104 and 106 formed near the root of the toes, at the arch portion and at the portion corresponding to the heel portion. Reference numeral 107 denotes a general portion 107 having no irregularities.

Since the polyurethane foam of the present embodiment used for the molded article 10 of the polyurethane foam in which the irregularities are formed by the thermal compression molding has good strain characteristics, even if the molded article is pushed by long-term use, the irregularities are hardly plastically deformed, and good quality can be maintained.

Examples

The following raw materials were used, and in the polyurethane reaction composition comprising the mixture of fig. 3 and 4, the mixing ratio of the inert gas (nitrogen gas) was 85% by volume, and the mixture was mixed and stirred by a mechanical foaming machine, and continuously discharged on a release paper and heated to 120 to 200 ℃, to prepare a sheet-like polyurethane foam having a thickness of 10 mm.

Crosslinking agent: dipropylene glycol having a molecular weight of 134, a functional group number of 2, and a solid content of 0 wt%

Polyol a: polyether polyol, product name; PP-400, manufactured by Sanyo chemical industry Co., ltd., molecular weight of 400, the number of functional groups of 2, and the solid content of 0% by weight

Polyol 1: polyether polyol, product name; PP-3000, manufactured by Sanyo chemical industry Co., ltd., molecular weight of 3000, the number of functional groups of 3, the propylene oxide content of 100% and the solid content of 0% by weight

Polyol 2: polymer polyol, product name; EX-914 manufactured by Asahi Kabushiki Kaisha, having a molecular weight of 3000, a number of functional groups of 3, and a solid content of 22.9 wt%

Polyol 3: polymer polyol, product name; EX-913 manufactured by Asahi Kabushiki Kaisha, having a molecular weight of 3000, a number of functional groups of 2, and a solid content of 20% by weight

Polyol 4: polymer polyol, product name; FS-7301, sanyo chemical industry Co., ltd., molecular weight of 3000, number of functional groups of 3, and solid content of 43% by weight

Polyol 5: polymer polyol, product name; EX-941WF, manufactured by Asahi Kabushiki Kaisha, has a molecular weight of 3000, a functional group number of 3, and a solid content of 40% by weight

Polyethylene (PE) powder in general: 1050, melting point=105℃, average particle size 30-45 μm, manufactured by Tokyo ink (Tokyo Printing Ink)

Polyamide resin powder: SK-1, melting point=115℃, manufactured by tokyo ink company

Polyester resin powder: g-120, melting point=125℃, manufactured by tokyo ink company

Acid modified Polyethylene (PE) powder: maleic anhydride modified polyethylene, product name; ADMER AT1000, melting point=123 ℃, average particle size 100 to 160 μm, manufactured by sanjingjingchu chemical co

Acid modified polypropylene (PP) powder: maleic anhydride modified polypropylene, product name; UMEX 1010, melting point=135 ℃, average particle diameter of 100 to 150 μm, manufactured by Sanyo chemical industry Co., ltd

Silicone foam stabilizer: product name; SZ-1952, manufactured by Dow Toray Co., ltd., tao Shidong

Iron catalyst: product name; FIN-P1, manufactured by Japanese chemical industry Co., ltd., iron acetylacetonate 0.25 wt%, polyether polyol 99.75 wt%

Alumina trihydrate: product name; c-31 manufactured by Sumitomo chemical Co

Isocyanate: product name; M5S, manufactured by basf well polyurethane (BASF INOAC Polyurethane), polymeric MDI (crude MDI), NCO; 34%

In addition, since Polyethylene (PE) powder, polyamide resin powder, polyester resin powder, acid-modified Polyethylene (PE) powder and acid-modified polypropylene (PP) powder are thermoplastic resin powder in general, they are shown as "thermoplastic resin powder" in fig. 3 and 4 as a classification including them.

"wt%" in fig. 3 and 4 is the weight% in the polyurethane reaction composition. Further, the total resin proportion (wt%) is the total amount of the thermoplastic resin powder and the solid components of the polymer polyol in the polyurethane reaction composition relative to the total amount of the polyurethane reaction composition.

Regarding each example and each comparative example, the foaming state was visually judged. The test was evaluated as "excellent" when there was no good such as breaking foam, and as "X" when there was a defective portion such as breaking foam.

Further, the initial formability, the forming retention after 24 hours at room temperature (25 ℃) and the forming retention after 1 week at room temperature (room temperature×1 week) were measured by performing the hot compression forming for each example and each comparative example.

For the hot press molding, a sheet of polyurethane foam having a thickness (original thickness) of 10mm was preheated at 200℃for 5 minutes, and then compressed to a thickness of 5mm (compression ratio: 50%) by a press at ordinary temperature, and this state was maintained for 5 minutes. In addition, at the time of pressing, spacers (spacers) having a thickness of 5mm were disposed on both sides of the sheet of polyurethane foam to press, thereby adjusting the pressing amount to 5mm.

Regarding the initial formability (%), the forming retention immediately after forming, in which the compressed state was maintained for 5 minutes, was calculated by [ (original thickness-thickness immediately after forming)/(original thickness-thickness of separator) ×100 ].

Regarding the molding retention (room temperature×24h (%)), the molding retention after 24 hours at room temperature after molding was calculated from [ (original thickness-thickness after 24 hours)/(original thickness-thickness immediately after molding) ×100 ].

Regarding the molding retention (room temperature×1 week (%)), the molding retention after molding and after leaving at room temperature for 1 week was calculated from [ (original thickness-thickness after 1 week)/(original thickness-thickness immediately after molding) ×100 ].

The evaluation of the initial formability and the forming retention was "x" when the forming retention was less than 50%, the evaluation of the initial formability and the forming retention was "Δ" when 50% to less than 70%, the evaluation of the initial formability and the forming retention was "good" when 70% to less than 90%, and the evaluation of the initial formability and the forming retention was "very good" when 90% to 100%.

Further, with respect to each example and each comparative example, 25% cld and compressive residual strain were measured.

25% CLD (MPa) was based on JIS K6254: 2010, will beThe samples of (2) were subjected to a compressive stress at 25% compression at a rate of 1 mm/min.

Compressive residual strain (%) is based on JIS K6401:2011, a sample of 50X 50mm was subjected to 50% compression in the thickness direction, allowed to stand at a predetermined temperature (70 ℃) for 22 hours, then subjected to 30 minutes after releasing the compressive stress at normal temperature, and the thickness of the sample (thickness after release) was measured, and a value calculated by the following expression was obtained.

Compressive residual strain (%) = [ (thickness before compression-thickness after release)/thickness before compression×100]

The evaluation of the compressive residual strain is "excellent" when the value of the compressive residual strain is 5% or less, the evaluation of the compressive residual strain is "good" when the value exceeds 5% and 10% or less, and the evaluation of the compressive residual strain is "x" when the value exceeds 10%.

Comprehensive evaluation was performed according to the results of each test item. Regarding the comprehensive evaluation, the lowest evaluation among the evaluations of each test item was taken as the comprehensive evaluation. For example, even if there is one "x" in the evaluation of the test item, the overall evaluation is "x"; when all the evaluations of the test items were "Δ" or more (the "Δ" "" n ""), and even if one was "Δ", the overall evaluation was "Δ". When all the evaluations of the test items are "good" or more ("good" "), and even if there is one" good ", the overall evaluation is" good "; when all the evaluations of the test items were "verygood", the comprehensive evaluation was "verygood".

Comparative example 1 is an example in which a polymer polyol is contained in a polyol component, and a usual polyethylene powder is added as a thermoplastic resin powder. As a result of comparative example 1, no other test was performed because the foam state had foam breaking. Comprehensive evaluation was "x".

Comparative example 2 is an example in which the polymer polyol is not contained in the polyol component, and the thermoplastic resin powder is not added. In comparative example 2, the foaming state was "verygood", the initial formability was evaluated as "×", the forming retention (room temperature×24 h) was 90.5%, the forming retention (room temperature×1 week) was evaluated as "verygood", the forming retention (room temperature×1 week) was 66.7%, the 25% cld was 0.015MPa, the compressive residual strain was 2.8%, the initial formability was evaluated as "verygood", and the overall evaluation was "×".

Comparative example 3 is an example in which the polymer polyol is contained in the polyol component, the thermoplastic resin powder is not added, the solid content of the polymer polyol in the polyurethane reaction composition is 5.0wt%, and the total resin content is 5.0 wt%. In comparative example 3, the foaming state was "good", the initial formability was evaluated as "×", the forming retention (room temperature×24 h) was 93.5%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 41.9%, the evaluation was "×", the 25% cld was 0.050MPa, the compressive residual strain was 2.7%, the evaluation was "good", the initial formability and the forming retention (room temperature×1 week) were poor, and the overall evaluation was "×".

Comparative example 4 is an example in which the polymer polyol is contained in the polyol component, the thermoplastic resin powder is not added, the solid content of the polymer polyol in the polyurethane reaction composition is made to be 7.7wt%, and the total resin content is made to be 7.7 wt%. In comparative example 4, the foaming state was "verygood", the initial formability was evaluated as "×", the forming retention (room temperature×24 h) was 91.7%, the forming retention (room temperature×1 week) was evaluated as "verygood", the forming retention (room temperature×1 week) was 64.3%, the 25% cld was 0.053MPa, the compressive residual strain was 2.5%, the initial formability was evaluated as "good", and the overall evaluation was "×".

Comparative example 5 is an example in which a polymer polyol is not contained in the polyol component, and 27.2wt% of a general polyethylene powder is added as a thermoplastic resin powder so that the total resin ratio is 27.2 wt%. In comparative example 5, the foaming state was "good", the initial formability was evaluated as "×", the forming retention (room temperature×24 h) was 82.5%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 38.6%, the 25% cld was evaluated as "×", the compression residual strain was 2.1%, the "good" was evaluated, the initial formability and the forming retention (room temperature×1 week) were poor, and the overall evaluation was "×".

Comparative example 6 is an example in which a polymer polyol was contained in the polyol component, a polyamide resin powder was added as a thermoplastic resin powder, the solid content of the polymer polyol in the polyurethane reaction composition was set to 13.0wt%, the addition ratio of the polyamide resin powder was set to 13.3wt%, and the total resin content was set to 26.3 wt%. In comparative example 6, the foaming state was "verygood", the initial moldability was evaluated as "×", the molding retention (room temperature×24 h) was 78.8%, the molding retention (room temperature×1 week) was evaluated as "no", 69.5%, the molding retention (room temperature×1 week) was evaluated as "Δ", the 25% cld was 0.103MPa, the compressive residual strain was 37.5%, the initial moldability and compressive residual strain were evaluated as "×", the initial moldability and compressive residual strain were poor, and the overall evaluation was "×".

Comparative example 7 is the same example as comparative example 6 except that polyester resin powder was used as the thermoplastic resin powder. In comparative example 7, the foaming state was "good", the initial formability was evaluated as "×", the forming retention (room temperature×24 h) was 78.2%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 69.4%, the 25% cld was 0.048MPa, the compressive residual strain was 18.8%, the initial formability and compressive residual strain were evaluated as "×", the initial formability and compressive residual strain were poor, and the overall evaluation was "×".

In example 1, 5 parts by weight of polyol 4 (POP, solid content ratio: 43 wt%) as a polymer polyol, 5 parts by weight of acid-modified polyethylene powder as a thermoplastic resin powder, 3.3wt% of polymer polyol in a polyurethane reaction composition, 1.4wt% of solid content of polymer polyol, 3.3wt% of acid-modified polyethylene powder in a polyurethane reaction composition, and 4.7wt% of total resin were added to 65.9 parts by weight of the total of the crosslinking agent and the polyol component. In example 1, the foaming state was "verygood", the initial formability was evaluated as "DELTA", the forming retention (room temperature. Times.24 h) was 71%, the forming retention (room temperature. Times.1 week) was evaluated as "good", the forming retention (room temperature. Times.1 week) was 60.3%, the 25% CLD was 0.691MPa, the compressive residual strain was 3.7%, the "excellent", and the overall evaluation was "DELTA". In example 1, since no "x" was found in all the evaluations, the initial formability, the forming retention and the compressive residual strain were all good, and thus the hot press forming was possible and the strain characteristics were good.

In example 2, the total amount of the crosslinking agent and the polyol component was 65.9 parts by weight, 20 parts by weight of polyol 4 (POP, solid content ratio: 43 wt%) was used as the polymer polyol, 13.2wt% of the polymer polyol was contained in the polyurethane reaction composition, 5.7wt% of the solid content ratio of the polymer polyol was contained, 3.3wt% of the acid-modified polyethylene powder was added to the polyurethane reaction composition, and 9.0wt% of the total resin was contained. In example 2, the foaming state was "verygood", the initial formability was evaluated as "verygood", the forming retention (room temperature×24 h) was 91.3%, the forming retention (room temperature×1 week) was 84.8%, the 25% cld was 0.715MPa, the compressive residual strain was 3.3%, the "excellent" was evaluated, and the overall evaluation was "no. In example 2, all of the materials were evaluated as "good" or more, and the initial formability, the forming retention and the compressive residual strain were all good, so that the hot press forming was possible, and the strain characteristics were good.

In example 3, the total amount of the crosslinking agent and the polyol component was 65.9 parts by weight, 40 parts by weight of polyol 4 (POP, solid content ratio: 43 wt%) as a polymer polyol was added, 10 parts by weight of acid-modified polyethylene powder was added, the content of the polymer polyol in the polyurethane reaction composition was 26.6wt%, the solid content ratio of the polymer polyol was 11.4wt%, the content of the acid-modified polyethylene powder in the polyurethane reaction composition was 6.6wt%, and the total resin content was 18.0 wt%. In example 3, the foaming state was "good", the initial formability was evaluated as "good", the forming retention (room temperature×24 h) was 92.2%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 88.5%, the 25% cld was evaluated as "good", 1.073MPa, the compressive residual strain was 3.7%, the "good" was evaluated as "good", and the overall evaluation was "good". In example 3, all of the materials were evaluated as "good" or more, and the initial formability, the forming retention and the compressive residual strain were all good, so that the hot press forming was possible, and the strain characteristics were good.

In example 4, 30 parts by weight of an acid-modified polyethylene powder was added to a total of 65.9 parts by weight of a crosslinking agent and a polyol component, wherein the total content of the polymer polyol was 19.8wt%, the solid content of the polymer polyol was 8.5wt%, the content of the acid-modified polyethylene powder was 19.8wt%, and the total resin content was 28.3wt%, and the content of polyol 4 (POP, solid content ratio was 43 wt%) was 30 parts by weight. In example 4, the foaming state was "good", the initial formability was evaluated as "good", the forming retention (room temperature×24 h) was 96.8%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 95.2%, the 25% cld was 0.669MPa, the compressive residual strain was 3.1%, the "good", the overall evaluation was "good". In example 4, all of the materials were evaluated as "excellent", and since the initial formability, the forming retention property, and the compressive residual strain were all good, the hot press forming was possible, and the strain characteristics were good.

Example 5 is an example in which the total resin ratio was made to have a value of 29.0wt% which is almost the same as 28.3wt% of example 4, and the ratio of the polymer polyol to the acid-modified polyethylene powder was changed. In example 5, in 65.9 parts by weight of the total of the crosslinking agent and the polyol component, 10 parts by weight of polyol 4 (POP, solid content ratio: 43 wt%) as a polymer polyol was added, 40 parts by weight of acid-modified polyethylene powder was added, the content of the polymer polyol in the polyurethane reaction composition was 6.6wt%, the solid content of the polymer polyol was 2.8wt%, the content of the acid-modified polyethylene powder in the polyurethane reaction composition was 26.2wt%, and the total resin content was 29.0wt%. In example 5, the foaming state was "good", the initial formability was evaluated as "good", the forming retention (room temperature×24 h) was 98.1%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 97.2%, the 25% cld was 0.550MPa, the compressive residual strain was 3.6%, the "good", the comprehensive evaluation was "good". In example 5, all of the materials were evaluated as "excellent", and since the initial formability, the forming retention property, and the compressive residual strain were all good, the hot press forming was possible, and the strain characteristics were good.

Example 6 is an example in which the content of the polymer polyol (polyol 4, solid content ratio: 43 wt%) in the polyurethane reaction composition was 6.3wt%, the solid content ratio of the polymer polyol was 2.7wt%, the content ratio of the acid-modified polyethylene powder in the polyurethane reaction composition was 31.3wt%, and the total resin ratio was 34.0wt% by adding the acid-modified polyethylene powder to 50 parts by weight. In example 6, the foaming state was "good", the initial formability was evaluated as "good", the forming retention (room temperature×24 h) was 98.8%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 97.9%, the 25% cld was 0.405MPa, the compressive residual strain was 4.6%, the "good", and the comprehensive evaluation was "good". In example 6, all of the materials were evaluated as "excellent", and since the initial formability, the forming retention property, and the compressive residual strain were all good, the hot press forming was possible, and the strain characteristics were good.

Example 7 is an example in which the content of the polymer polyol (polyol 4, solid content ratio: 43 wt%) in the polyurethane reaction composition was 26.6wt%, the solid content ratio of the polymer polyol was 11.4wt%, the content of the acid-modified polypropylene powder in the polyurethane reaction composition was 6.6wt%, and the total resin content was 18.0wt%, except that the acid-modified polypropylene powder was added instead of the acid-modified polyethylene, as in example 3. In example 7, the foaming state was "verygood", the initial formability was evaluated as "verygood", the forming retention (room temperature×24 h) was 91.5%, the forming retention (room temperature×1 week) was 87.2%, the 25% cld was 1.082MPa, the compressive residual strain was 3.8%, and the overall evaluation was "very good". In example 7, all of the materials were evaluated as "good" or more, and the initial formability, the forming retention and the compressive residual strain were all good, so that the hot press forming was possible, and the strain characteristics were good.

In example 8, 30 parts by weight of polyol 3 (POP, solid content ratio: 20 wt%) as a polymer polyol, and 30 parts by weight of acid-modified polyethylene powder as a thermoplastic resin powder were added to 65.9 parts by weight of the total of the crosslinking agent and the polyol component, the content of the polymer polyol in the polyurethane reaction composition was 19.8wt%, the solid content of the polymer polyol was 4.0wt%, the content of the acid-modified polyethylene powder in the polyurethane reaction composition was 19.8wt%, and the total resin content was 23.8 wt%. In example 8, the foaming state was "verygood", the initial formability was evaluated as "good", the forming retention (room temperature×24 h) was 75.4%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 73.6%, the 25% cld was 0.187MPa, the compressive residual strain was 4.8%, the evaluation as "good", and the overall evaluation was "good". In example 8, all of the materials were evaluated as "good" or more, and the initial formability, the forming retention and the compressive residual strain were all good, so that the hot press forming was possible, and the strain characteristics were good.

In example 9, the total amount of the crosslinking agent and the polyol component was 65.9 parts by weight, 40 parts by weight of polyol 3 (POP, solid content ratio: 20 wt%) was used as the polymer polyol, 26.6wt% of the polymer polyol in the polyurethane reaction composition, 5.3wt% of the solid content ratio of the polymer polyol, and 19.9wt% of the acid-modified polyethylene powder in the polyurethane reaction composition was used, and the total resin content was 25.2 wt%. In example 9, the foaming state was "verygood", the initial formability was evaluated as "good", the forming retention (room temperature×24 h) was 81.2%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 80.8%, the 25% cld was 0.212MPa, the compressive residual strain was 4.5%, and the overall evaluation was "very good". In example 9, all of the materials were evaluated as "good" or more, and the initial formability, the forming retention and the compressive residual strain were all good, so that the hot press forming was possible, and the strain characteristics were good.

Example 10 is an example in which the content of the acid-modified polyethylene powder in the polyurethane reaction composition was 40 parts by weight, the content of the polymer polyol (polyol 3, solid content ratio: 20% by weight) in the polyurethane reaction composition was 18.6% by weight, the solid content ratio of the polymer polyol was 3.7% by weight, the content of the acid-modified polyethylene powder in the polyurethane reaction composition was 24.8% by weight, and the total resin content was 28.5% by weight. In example 10, the foaming state was "good", the initial formability was evaluated as "good", the forming retention (room temperature×24 h) was 90.1%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 88.9%, the 25% cld was 0.183MPa, the compressive residual strain was 5.5%, the "good" was evaluated as "integral", and the overall evaluation was "good". In example 10, all of the materials were evaluated as "good" or more, and the initial formability, the forming retention and the compressive residual strain were all good, so that the hot press forming was possible, and the strain characteristics were good.

Example 11 is an example in which the content of the acid-modified polyethylene powder in the polyurethane reaction composition was 40 parts by weight, the content of the polymer polyol (polyol 3, solid content ratio: 20% by weight) in the polyurethane reaction composition was 24.9% by weight, the solid content ratio of the polymer polyol (polyol 3, solid content ratio: 20% by weight) was 5.0% by weight, the content of the acid-modified polyethylene powder in the polyurethane reaction composition was 24.9% by weight, and the total resin ratio was 29.9% by weight. In example 11, the foaming state was "verygood", the initial formability was evaluated as "verygood", the forming retention (room temperature×24 h) was 87.5%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 86.1%, the 25% cld was evaluated as "good", the compression residual strain was 3.3%, the "good" was evaluated as "good", and the overall evaluation was "good". In example 11, all of the materials were evaluated as "good" or more, and the initial formability, the forming retention property, and the compressive residual strain were all good, so that the hot press forming was possible, and the strain characteristics were good.

In example 12, 30 parts by weight of polyol 5 (POP, 40% by weight in solid content) as a polymer polyol, and 30 parts by weight of acid-modified polyethylene powder as a thermoplastic resin powder were added to 65.9 parts by weight of the total of the crosslinking agent and the polyol component, 19.8% by weight of the polymer polyol content in the polyurethane reaction composition, 7.9% by weight of the solid content in the polymer polyol content, 19.8% by weight of the acid-modified polyethylene powder content in the polyurethane reaction composition, and 27.7% by weight of the total resin content were obtained. In example 12, the foaming state was "good", the initial formability was evaluated as "good", the forming retention (room temperature×24 h) was 91.5%, the forming retention (room temperature×1 week) was evaluated as "good", the forming retention (room temperature×1 week) was 82.6%, the 25% cld was 0.139MPa, the compressive residual strain was 5.7%, the "good" was evaluated, and the overall evaluation was "good". In example 12, all of the materials were evaluated as "good" or more, and the initial formability, the forming retention and the compressive residual strain were all good, so that the hot press forming was possible, and the strain characteristics were good.

In order to confirm the influence of the preheating temperature on the surface state of the molded article and the molding retention (moldability), the polyurethane foam of example 4 was used, and the preheating temperature and the preheating time were varied to perform the thermal compression molding, and the surface state after preheating and the molding retention after the thermal compression molding were determined. The results of each example and each comparative example are shown in fig. 5. In addition, in the results shown in fig. 5, examples of the preheating temperature range in the thermal compression molding are taken as examples, and examples of the preheating temperature range not in the thermal compression molding are taken as comparative examples. The hot press molding was performed as follows. First, a sheet of polyurethane foam having a thickness (original thickness) of 10mm was preheated at the preheating temperature and preheating time of each example and each comparative example. Then, spacers having a thickness of 5mm were placed on both sides of the sheet of polyurethane foam, and the sheet was compressed to a thickness of 5mm (compression ratio 50%) by a pressing device at normal temperature (25 ℃) and maintained in this state for 5 minutes.

Regarding the judgment of the surface state, the surface of the polyurethane foam after preheating was visually observed, and evaluated as "x" when there was surface burn and surface roughness, and as "" jinji "when there was no surface burn and surface roughness, and the surface state was smooth.

Regarding the forming retention, the thickness of the formed article was measured at each time immediately after the hot press forming, after 1 day, and after 1 week, and the forming retention (%) was calculated by the following expression, and was evaluated as "x" when the calculated forming retention (%) was less than 50%, as "Δ" when it was 50% to less than 70%, as "good" when it was 70% to less than 90%, and as "good" when it was 90% to 100%.

Shape retention (%) = (original thickness-thickness at measurement)/(original thickness-thickness of separator) ×100

Example 4-1 shows that the preheating temperature was 190℃and the preheating time was 3 minutes, the surface state was "verygood", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", and the molding retention after 1 week was "good", and the surface state and the molding retention (moldability) were both good.

Example 4-2 shows that the preheating temperature was 200℃and the preheating time was 3 minutes, the surface state was "verygood", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", and the molding retention after 1 week was "good", and the surface state and the molding retention (moldability) were both good.

Examples 4 to 3 are examples in which the preheating temperature was 210℃and the preheating time was 3 minutes, the surface state was "good", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", the molding retention after 1 week was "good", and the surface state and the molding retention (moldability) were both the best.

Comparative example 4-1 shows that the preheating temperature was 220 ℃ and the preheating time was 3 minutes, the surface state was "x", the molding retention immediately after molding was "very good", the molding retention after 1 day was "very good", and the molding retention after 1 week was "very good", and the surface state was poor because the preheating temperature was too high.

Comparative example 4-2 shows that the preheating temperature was 150 ℃ and the preheating time was 4 minutes, the surface state was "verygood", the molding retention immediately after molding was "verygood", the molding retention after 1 day was "Δ", and the molding retention after 1 week was "Δ", and the molding retention (moldability) was poor because the preheating temperature was too low.

Examples 4 to 4 are examples in which the preheating temperature was 160℃and the preheating time was 4 minutes, the surface state was "verygood", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", and the molding retention after 1 week was "good", and both the surface state and the molding retention (moldability) were good.

Examples 4 to 5 are examples in which the preheating temperature was 170℃and the preheating time was 4 minutes, the surface state was "verygood", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", and the molding retention after 1 week was "good", and both the surface state and the molding retention (moldability) were good.

Examples 4 to 6 are examples in which the preheating temperature was 180℃and the preheating time was 4 minutes, the surface state was "verygood", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", and the molding retention after 1 week was "good", and both the surface state and the molding retention (moldability) were good.

Examples 4 to 7 are examples in which the preheating temperature was 190℃and the preheating time was 4 minutes, the surface state was "verygood", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", and the molding retention after 1 week was "good", and both the surface state and the molding retention (moldability) were good.

Examples 4 to 8 are examples in which the preheating temperature was 200℃and the preheating time was 4 minutes, the surface state was "good", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", the molding retention after 1 week was "good", and the surface state and the molding retention (moldability) were both optimal.

Comparative examples 4 to 3 are examples in which the preheating temperature was 150℃and the preheating time was 5 minutes, the surface state was "verygood", the molding retention immediately after molding was "verygood", the molding retention after 1 day was "DELTA", and the molding retention after 1 week was "DELTA", and the molding retention (moldability) was poor because the preheating temperature was too low.

Examples 4 to 9 are examples in which the preheating temperature was 160℃and the preheating time was 5 minutes, the surface state was "verygood", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", and the molding retention after 1 week was "good", and both the surface state and the molding retention (moldability) were good.

Examples 4 to 10 are examples in which the preheating temperature was 170℃and the preheating time was 5 minutes, the surface state was "verygood", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", and the molding retention after 1 week was "good", and both the surface state and the molding retention (moldability) were good.

Examples 4 to 11 are examples in which the preheating temperature was 180℃and the preheating time was 5 minutes, the surface state was "verygood", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", and the molding retention after 1 week was "good", and both the surface state and the molding retention (moldability) were good.

Examples 4 to 12 are examples in which the preheating temperature was 190℃and the preheating time was 5 minutes, the surface state was "good", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", the molding retention after 1 week was "good", and the surface state and the molding retention (moldability) were both optimal.

Examples 4 to 13 are examples in which the preheating temperature was 200℃and the preheating time was 5 minutes, the surface state was "good", the molding retention immediately after molding was "good", the molding retention after 1 day was "good", the molding retention after 1 week was "good", and the surface state and the molding retention (moldability) were both optimal.

Thus, the polyurethane foam of the present invention can be hot-press molded and has excellent strain characteristics. The polyurethane foam molded article of the present invention can maintain the irregularities of the surface molded by hot compression molding and has good strain characteristics. Further, the method for producing a molded article of a polyurethane foam of the present invention can provide a molded article having excellent strain characteristics, which can maintain irregularities on the surface of a sheet molded by hot compression molding, has a flat surface state with no surface burn and excellent roughness, and has excellent molding retention (moldability).

Although the present invention has been described in detail with reference to specific embodiments, it will be apparent to one skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope thereof.

In addition, the present application is based on Japanese patent application No. 10/2019 (Japanese patent application No. 2019-186657), japanese patent application No. 5/29/2020 (Japanese patent application No. 2020-94119) and Japanese patent application No. 10/2020 (Japanese patent application No. 2020-171088), the disclosures of which are incorporated herein by reference in their entirety. Further, the disclosures of all references cited therein are incorporated in their entirety into the present application.

Description of the reference numerals

10. Molded article of polyurethane foam

101. 103 concave part

102. 104, 106 convex portions

107. General portion without irregularities

Claims

1. A polyurethane foam obtained by a mechanical foaming method from a polyurethane reaction composition containing a polyol component, a foam stabilizer, a catalyst and an isocyanate component,

the polyol component contains 20 to 43 wt% of a polymer polyol as a solid component,

the polyurethane reaction composition comprises an acid modified polyolefin powder.

2. The polyurethane foam according to claim 1, wherein the acid-modified polyolefin powder is a polyolefin powder modified with maleic anhydride.

3. The polyurethane foam according to claim 1 or 2, wherein the ratio of the total weight of the solid component of the polymer polyol and the acid-modified polyolefin powder to the weight of the polyurethane reaction composition is 4 to 40% by weight.

4. The polyurethane foam according to claim 1 or 2, wherein the polyurethane foam is based on JIS K6401:2011 is 10% or less.

5. A molded article of a polyurethane foam, which is a molded article obtained by molding irregularities by thermal compression molding on the surface of a sheet of a polyurethane foam,

the polyurethane foam according to any one of claims 1 to 4.

6. A method for producing a molded article having a surface of a sheet of a polyurethane foam, the surface being provided with irregularities by thermal compression molding, the method comprising:

a sheet comprising the polyurethane foam of any one of claims 1 to 4 is preheated at 160 to 210 ℃,

And performing thermal compression molding, wherein the thermal compression molding uses a normal-temperature mold with concave and convex surfaces on the surface of the mold to compress and press the preheated sheet, and the concave and convex surfaces on the surface of the mold are formed on the surface of the sheet.

7. The method for producing a molded article according to claim 6, wherein the compression ratio of the sheet by the compression molding is 25 to 75%.

8. A process for producing the polyurethane foam as claimed in any one of claims 1 to 4, which comprises,

in the mixed raw material in which an inert gas is mixed into the polyurethane reaction composition, the inert gas forms bubbles, and in this state, the polyol component reacts with the isocyanate component and cures.