CN114514273A

CN114514273A - Polyurethane foam, molded article thereof, and process for producing molded article

Info

Publication number: CN114514273A
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: 2022-05-17
Anticipated expiration: 2040-10-09
Also published as: JP2021185217A; CN114514273B

Abstract

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

Description

Polyurethane foam, molded article thereof, and process 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

The thermoplastic resin can be shaped by heating, but has a problem of poor strain characteristics (large strain).

On the other hand, a thermosetting resin can be shaped by a preliminary processing using a mold, and although a post-processing is difficult, it has an advantage of good strain characteristics (less strain).

Further, although the conventional polyurethane foam can be subjected to thermocompression molding at high temperature, it has a problem that the strain characteristics are not good.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 2009-013304

Disclosure of Invention

Problems to be solved by the invention

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

Means for solving the problems

The 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 through a polyurethane reaction composition and an inert gas, wherein the polyurethane reaction composition comprises a polyol component, a foam stabilizer, a catalyst and an isocyanate component, the polyol component comprises polymer polyol with the solid content of 20-43 wt%, and the polyurethane reaction composition comprises acid modified polyolefin powder.

(2) In the polyurethane foam of the above (1), it is preferable that the acid-modified polyolefin powder is 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 content 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), the polyurethane foam preferably has a hardness in accordance with JIS K6401: 2011 has a compression residual strain of 10% or less.

(5) A molded article of a polyurethane foam according to an aspect of the present invention that can solve the above problems is a molded article having unevenness shaped by thermal compression molding on a surface of a sheet of a polyurethane foam, and 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 an aspect of the present invention that can solve the above problems is a method for producing a molded article having irregularities shaped by thermocompression molding on a surface of a sheet of a polyurethane foam, wherein the sheet including the polyurethane foam according to any one of (1) to (4) above is preheated at 160 to 210 ℃, and is thermocompression molded, and the thermocompression molding is performed by using a normal temperature mold having irregularities provided on a mold surface to compress and press the preheated sheet and shaping the irregularities on the mold surface on the surface of the sheet.

(7) In the method for producing a molded body according to the above (6), the sheet preferably has a compressibility of 25 to 75% at the time of the compression pressing.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the polyurethane foam of the present invention, by including the polymer polyol having a solid content of 20 to 43 wt% and the acid-modified polyolefin powder in the polyurethane reaction composition, the polyurethane foam can be thermoplastically deformed at a temperature of not higher than the decomposition temperature of the urethane bond, and the shape of the polyurethane foam during hot 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 surface roughness of the molded article shaped by the thermocompression molding can be maintained.

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 is subjected to thermocompression molding, and the preheated sheet is subjected to compression pressing using a normal-temperature mold having irregularities on the mold surface, whereby a molded article having excellent strain characteristics can be obtained, which can maintain the irregularities on the sheet surface shaped by thermocompression molding, has a surface state having no surface burn and good roughness, and has excellent molding retention properties (moldability).

Drawings

Fig. 1 is a plan view showing an embodiment of a molded article 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 compounding, shape retention, 25% CLD, and compressive residual strain of a part of examples and comparative examples.

Fig. 4 is a table showing the values and evaluations of fit, form 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

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

The mechanical foaming method is a method of forming a polyurethane foam by feeding a mixed raw material, which is mixed into a polyurethane reaction composition by compressing an inert gas, to an Oakes Mixer (Oakes Mixer, オークスミキサー) or a nozzle whose tip is narrowed and discharging from the Oakes Mixer or the nozzle. In the mechanical foaming method, when the mixed raw materials are discharged, the inert gas compressed before the discharge expands to form cells, and in this state, the polyol component and the isocyanate component react and cure to form 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 includes a polyol component, a foam stabilizer, a catalyst, and an isocyanate component, and in this embodiment includes an acid-modified polyolefin powder. Further, as the foaming functional agent (foaming agent), an inert gas is contained as a mixed raw material.

In the polyol component, a polyol other than the polymer polyol may be contained together with the polymer polyol.

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

The content ratio 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, an appropriate hardness cannot be obtained, and if the content is large, the viscosity of the polyurethane reaction composition is excessively increased, and foaming by mechanical foaming is difficult. 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 thermal forming is difficult and the molding retentivity is deteriorated, whereas if it is large, the thermal forming is easy but the viscosity of the polymer polyol is excessively increased and the handling may be difficult.

As the polyol other than the polymer polyol, known polyols, for example, polyether polyol, polyester polyol and the like can be used. The polyether polyol is preferably a polyether polyol having a molecular weight of 300 to 5000 and a functional group number of 2 to 4, and the polyester polyol is preferably a polyester polyol having a molecular weight of 300 to 3000 and a functional group number of 2 to 4. The polyols other than the polymer polyol may be used in combination of two or more kinds.

As the foam stabilizer, a known foam stabilizer 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 for example, the amount of the foam stabilizer may be 1.0 to 6.0 parts by weight per 100 parts by weight of the polyol component.

As the catalyst, an amine-based catalyst or an organic metal catalyst used for the polyurethane foam is used alone or in combination. The amine catalyst includes a monoamine compound, a diamine compound, a triamine compound, a polyamine compound, a cyclic amine compound, an alcohol amine compound, an ether amine compound, and the like, and 1 kind of them may be used, or 2 or more kinds may be used in combination. The organometallic catalyst includes an organotin compound, an organoiron compound, an organobismuth compound, an organolead compound, an organozinc compound, and the like, and 1 kind or 2 or more kinds of them may be used. The amount of the catalyst may be appropriately determined, and is exemplified by 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, and may be a 2-functional isocyanate having 2 isocyanate groups in 1 molecule or a 3-functional or higher isocyanate having 3 or more isocyanate groups in 1 molecule, or may be used alone or in combination of two or more thereof.

Examples of the 2-functional isocyanate include aromatic isocyanates such as 2, 4-Tolylene Diisocyanate (TDI), 2, 6-Tolylene 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, and methylcyclohexane diisocyanate; aliphatic isocyanates such as butane-1, 4-diisocyanate, hexamethylene diisocyanate, isopropene diisocyanate, methylene diisocyanate, and lysine isocyanate.

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

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

Among the acid-modified polyolefins, preferred is an acid-modified polyolefin modified with maleic anhydride. 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 maleic anhydride-modified polypropylene which is a polypropylene modified with maleic anhydride and is a random copolymer with ethylene, and the maleic anhydride-modified ethylene-propylene copolymer includes a maleic anhydride-modified ethylene-propylene copolymer which is a polypropylene modified with maleic anhydride and is a so-called block copolymer obtained by 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 polyolefins. The acid-modified polyolefin powder is not limited to one kind, and may contain a plurality of kinds. The powder is a powder having a particle diameter of 5 to 250 μm. The melting point of the acid modified polyolefin can be 80-165 ℃, and preferably 90-140 ℃.

By including the acid-modified polyolefin powder in the polyurethane reaction composition together with the polymer polyol, the polyurethane foam can be preheated at a temperature higher than the melting point of the acid-modified polyolefin powder, and can be subjected to thermoplastic deformation (thermal compression molding) at a temperature not higher than the decomposition temperature of the urethane bond, and the strain characteristics are good.

The content ratio of the acid-modified polyolefin powder in the polyurethane reaction composition is preferably 3 to 35% by weight. If the content ratio of the acid-modified polyolefin powder is small, thermal forming cannot be performed, and if the content ratio is large, foaming by mechanical foaming cannot be performed due to an 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, and more preferably 10 to 40% by weight. If the total weight (total resin amount) of the solid content of the polymer polyol and the acid-modified polyolefin powder is reduced, the heat-forming is not performed and the molding retentivity is also reduced. On the contrary, if the total resin amount is increased, the viscosity of the polyurethane reaction composition is excessively increased and foaming by mechanical foaming cannot be performed.

In addition, any additives 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 (blowing agent), a gas which does not adversely affect the reaction of the polyol with the 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 a volume% of the foaming gas with respect 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 is less plastically deformed by long-term use.

Further, the polyurethane foam of the present embodiment is preferably a polyurethane foam having a 25% compressive load (25% CLD, JIS K6254: 2010, prepared by mixing

The compressive stress of the sample (2) when the sample is compressed at a rate of 1mm/min by 25%) is 0.01 to 0.1 MPa.

The molded article of the polyurethane foam of the present embodiment is produced by shaping the unevenness by thermocompression molding including preheating the polyurethane foam and compression pressing with a room-temperature mold. The thermal compression molding is carried out by preheating the polyurethane foam at 160 to 210 ℃, more preferably 190 to 210 ℃, and compression-pressing the polyurethane foam by a mold at normal 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 purpose of the molded body in advance so as to form irregularities on the surface of the molded body. The compression ratio in compression and pressurization is preferably 25 to 75%. The compression ratio is calculated by [ (original thickness-thickness at the time of compression)/original thickness × 100 ].

Fig. 1 and 2 show an example of a molded article of a polyurethane foam. The polyurethane foam molded product 10 shown in fig. 1 and 2 is formed with irregularities by hot compression molding in which a sheet of the polyurethane foam of the present embodiment formed to have a predetermined thickness is preheated at 200℃ × 5 minutes and the preheated sheet is compressed at normal temperature (25 ℃) to be used as an insole. The polyurethane foam molded body 10 has recessed

portions

101 and 103 and raised

portions

102, 104, and 106 formed near the root of the toe, in the arch portion, and in the region corresponding to the heel portion. Reference numeral 107 denotes a general portion 107 having no concavity and convexity.

Since the polyurethane foam of the present embodiment used for the molded article 10 in which the uneven polyurethane foam is formed by the thermocompression molding has good strain characteristics, even when pressed by long-term use, the uneven shape is less likely to be plastically deformed, and good quality can be maintained.

Examples

In the polyurethane reaction composition including the formulations of fig. 3 and 4, the following raw materials were used, and a mixing ratio of an inert gas (nitrogen gas) was adjusted to 85 vol%, and the mixture was mixed and stirred by a mechanical foaming machine, 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% by weight

Polyol a: polyether polyol, product name; PP-400, available from Sanyo chemical industries, molecular weight 400, number of functional groups 2, solid content 0% by weight

Polyol 1: polyether polyol, product name; PP-3000, available from Sanyo chemical industries, having a molecular weight of 3000, a functional group number of 3, a propylene oxide content of 100%, and a solid content of 0% by weight

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

Polyol 3: polymer polyol, product name; EX-913, Asahi glass company, molecular weight 3000, number of functional groups 2, solid content 20% by weight

Polyol 4: polymer polyol, product name; FS-7301, manufactured by Sanyo chemical industries Ltd, having a molecular weight of 3000, a functional group number of 3, and a solid content of 43% by weight

Polyol 5: polymer polyol, product name; EX-941WF, Asahi glass company, molecular weight 3000, number of functional groups 3, solid content 40 wt%

Polyethylene (PE) powder in general: 1050, melting point 105 ℃ and average particle diameter 30 to 45 μm, manufactured by Tokyo Printing Ink

Polyamide resin powder: SK-1, melting point 115 ℃, manufactured by Tokyo ink Co., Ltd

Polyester resin powder: g-120 having a melting point of 125 ℃ manufactured by Tokyo ink Co., Ltd

Acid-modified Polyethylene (PE) powder: maleic anhydride modified polyethylene, product name; ADMER AT1000 having a melting point of 123 ℃ and an average particle diameter of 100 to 160 μm, manufactured by Mitsui chemical Co., Ltd

Acid-modified polypropylene (PP) powder: maleic anhydride modified polypropylene, product name; UMEX 1010 having a melting point of 135 ℃ and an average particle diameter of 100 to 150 μm, manufactured by Sanyo chemical industries Ltd

Silicone foam stabilizers: the name of the product; SZ-1952, manufactured by Dow Toray

Iron catalyst: a product name; FIN-P1, manufactured by Nippon chemical industries, 0.25 wt.% of iron acetylacetonate and 99.75 wt.% of polyether polyol

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

Isocyanate (ii): the name of the product; M5S, manufactured by BASF INOAC Polyurethane, polymeric MDI (crude MDI), NCO%; 34 percent of

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

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

The foaming state was visually judged for each example and each comparative example. The evaluation was "excellent" when no bubble was broken, and "x" when there was a defective portion such as a broken bubble.

Further, each example and each comparative example were subjected to thermocompression molding, and the initial moldability, the molding retention after 24 hours at room temperature (25 ℃) (room temperature × 24h), and the molding retention after 1 week at room temperature (room temperature × 1 week) were measured.

For the hot compression molding, a sheet of a 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 of 50%) by a press at normal temperature 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 the polyurethane foam, and the pressing amount was adjusted to 5 mm.

Regarding the initial moldability (%), the molding retention immediately after molding, in which the above-described compressed state was maintained for 5 minutes, was calculated from [ (original thickness-thickness immediately after molding)/(original thickness-thickness of separator) × 100 ].

Regarding the molding retention (room temperature × 24h (%)), the molding retention after 24 hours of standing 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 property (room temperature × 1 week (%)), the molding retention after molding and after leaving at room temperature for 1 week was calculated by [ (original thickness-thickness after 1 week)/(original thickness-thickness immediately after molding) × 100 ].

The evaluation of the initial formability and the forming retention property was "x" in the case where the forming retention rate was less than 50%, the evaluation of the initial formability and the forming retention property was "Δ" in the case where 50% to less than 70%, the evaluation of the initial formability and the forming retention property was "good" in the case where 70% to less than 90%, and the evaluation of the initial formability and the forming retention property was "excellent" in the case where 90% to 100%.

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

25% CLD (MPa) is based on JIS K6254: 2010, mixing the raw materials

The sample (2) was subjected to a compressive stress at a rate of 1mm/min at 25% compression.

Compression residual strain (%) was based on JIS K6401: 2011, a sample of 50 × 50mm is 50% compressed in the thickness direction, left to stand at a predetermined temperature (70 ℃) for 22 hours, then the compressive stress is released at normal temperature and after 30 minutes, the thickness of the sample (thickness after release) is measured and calculated by the following equation.

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

The evaluation of the compressive residual strain was "excellent" when the value of the compressive residual strain was 5% or less, the evaluation of the compressive residual strain was "good" when it exceeded 5% and was 10% or less, and the evaluation of the compressive residual strain was "poor" when it exceeded 10%.

The results of the test items were evaluated comprehensively. The lowest evaluation among the evaluations of the test items was regarded as the overall evaluation. For example, in the evaluation of test items, the overall evaluation is "x" even if there is one; all the evaluations of the test items were "Δ" or more ("Δ" "good" and "excellent"), and even if one of the evaluations was "Δ", the overall evaluation was "Δ". The evaluation of the test items were all "good" or more ("good" and excellent "), and the comprehensive evaluation was" good "even with one" good "in the evaluation; when all the evaluations of the test items are "excellent", the comprehensive evaluation is "excellent".

Comparative example 1 is an example in which a polymer polyol is contained in a polyol component, and a normal polyethylene powder is added as a thermoplastic resin powder. As a result of comparative example 1, since the foamed state had broken bubbles, no other test was conducted. The total evaluation was "X".

Comparative example 2 is an example in which no polymer polyol is contained in the polyol component and no thermoplastic resin powder is added. In comparative example 2, the foam state was ". circleincircle", the initial moldability was 10.6%, the evaluation was ". times", the molding retention (room temperature × 24h) was 90.5%, the evaluation was ". circleircle", the molding retention (room temperature × 1 week) was 66.7%, the evaluation was ". DELTA", the 25% CLD was 0.015MPa, the compression residual strain was 2.8%, the evaluation was ". circleircle", the initial moldability was poor, and the comprehensive evaluation was ". times".

Comparative example 3 is an example in which the polymer polyol is contained in the polyol component, and the thermoplastic resin powder is not added, so that the solid content of the polymer polyol in the polyurethane reaction composition is 5.0 wt%, and the total resin content is 5.0 wt%. In comparative example 3, the foam state was ". circleincircle", the initial moldability was 20.5%, the evaluation was ". times.", the molding retention (room temperature × 24h) was 93.5%, the evaluation was ". circleircle", the molding retention (room temperature × 1 week) was 41.9%, the evaluation was ". times.", the 25% CLD was 0.050MPa, the compression residual strain was 2.7%, the evaluation was ". circleircle", the initial moldability and the molding retention (room temperature × 1 week) were poor, and the comprehensive evaluation was ". times.".

Comparative example 4 is an example in which the polymer polyol was contained in the polyol component, and the thermoplastic resin powder was not added, so that the solid content of the polymer polyol in the polyurethane reaction composition was 7.7 wt%, and the total resin content was 7.7 wt%. In comparative example 4, the foam state was ". circleincircle", the initial moldability was 35.1%, the evaluation was ". times", the molding retention (room temperature × 24h) was 91.7%, the evaluation was ". circleircle", the molding retention (room temperature × 1 week) was 64.3%, the evaluation was ". DELTA", the 25% CLD was 0.053MPa, the compression residual strain was 2.5%, the evaluation was ". circleircle", the initial moldability was poor, and the overall evaluation was ". times".

Comparative example 5 is an example in which no polymer polyol is contained in the polyol component, and 27.2 wt% of a usual polyethylene powder is added as a thermoplastic resin powder to make the total resin ratio 27.2 wt%. In comparative example 5, the foam state was ". circleincircle", the initial moldability was 28.2%, the evaluation was ". times.", the molding retention (room temperature × 24h) was 82.5%, the evaluation was "good", the molding retention (room temperature × 1 week) was 38.6%, the evaluation was ". times.", the 25% CLD was 0.028MPa, the compression residual strain was 2.1%, the evaluation was ". circleincircle", the initial moldability and the molding retention (room temperature × 1 week) were poor, and the comprehensive evaluation was ". times.".

Comparative example 6 is an example in which a polymer polyol is contained in a polyol component, polyamide resin powder is added as thermoplastic resin powder, the solid content of the polymer polyol in the polyurethane reaction composition is made 13.0 wt%, the addition ratio of the polyamide resin powder is made 13.3 wt%, and the total resin ratio is made 26.3 wt%. In comparative example 6, the foaming state was "+", the initial formability was 31.8%, the evaluation was "×", the molding retention (room temperature × 24h) was 78.8%, the evaluation was "good", the molding retention (room temperature × 1 week) was 69.5%, the evaluation was "+", the 25% CLD was 0.103MPa, the compression residual strain was 37.5%, the evaluation was "×", the initial formability and the compression residual strain were poor, and the comprehensive evaluation was "×".

Comparative example 7 is the same example as comparative example 6 except that polyester resin powder is used as the thermoplastic resin powder. In comparative example 7, the foam state was ". circleincircle", the initial moldability was 30.4%, the evaluation was "x", the molding retention (room temperature × 24h) was 78.2%, the evaluation was "good", the molding retention (room temperature × 1 week) was 69.4%, the evaluation was "Δ", the 25% CLD was 0.048MPa, the compression residual strain was 18.8%, the evaluation was "x", the initial moldability and the compression residual strain were poor, and the overall evaluation was "x".

Example 1 is an example in which, in 65.9 parts by weight of the total of the crosslinking agent and the polyol component, 5 parts by weight of polyol 4 (POP) as a polymer polyol was added as a thermoplastic resin powder, 5 parts by weight of acid-modified polyethylene powder was added, the content of the polymer polyol in the polyurethane reaction composition was set to 3.3 wt%, the content of the solid of the polymer polyol was set to 1.4 wt%, the content of the acid-modified polyethylene powder in the polyurethane reaction composition was set to 3.3 wt%, and the total resin ratio was set to 4.7 wt%. In example 1, the foam state was ". cndot.", the initial moldability was 63.5%, the evaluation was "Δ", the molding retention (room temperature × 24h) was 71%, the evaluation was "good", the molding retention (room temperature × 1 week) was 60.3%, the evaluation was "Δ", the 25% CLD was 0.691MPa, the compression residual strain was 3.7%, the evaluation was ". cndot", and the overall evaluation was "Δ". In example 1, no "x" was found in all the evaluations, and the initial formability, the forming retention property, and the compressive residual strain were all good, so that the hot compression forming was possible and the strain characteristics were good.

Example 2 is an example in which, in 65.9 parts by weight of the total of the crosslinking agent and the polyol component, the polymer polyol, polyol 4(POP, solid content ratio of 43 wt%) was set to 20 parts by weight, the polymer polyol content in the polyurethane reaction composition was set to 13.2 wt%, the polymer polyol solid content was set to 5.7 wt%, the acid-modified polyethylene powder addition ratio in the polyurethane reaction composition was set to 3.3 wt%, and the total resin ratio was set to 9.0 wt%. In example 2, the foam state was "very good", the initial moldability was 97.9%, the evaluation was "very good", the molding retention property (room temperature × 24h) was 91.3%, the evaluation was "very good", the molding retention property (room temperature × 1 week) was 84.8%, the evaluation was "good", the 25% CLD was 0.715MPa, the compression residual strain was 3.3%, the evaluation was "very good", and the comprehensive evaluation was "good". In example 2, all evaluations were "good" or more, and the initial formability, the forming retention property, and the compressive residual strain were good, so that the hot compression forming was possible and the strain characteristics were good.

Example 3 is an example in which, in 65.9 parts by weight of the total of the crosslinking agent and the polyol component, polyol 4(POP, solid content ratio of 43 wt%) as a polymer polyol was 40 parts by weight, and 10 parts by weight of the acid-modified polyethylene powder was added so that the content ratio of the polymer polyol in the polyurethane reaction composition was 26.6 wt%, the solid content ratio of the polymer polyol was 11.4 wt%, the addition ratio of the acid-modified polyethylene powder in the polyurethane reaction composition was 6.6 wt%, and the total resin ratio was 18.0 wt%. In example 3, the foam state was "very good", the initial moldability was 95.4%, the evaluation was "very good", the molding retention property (room temperature × 24h) was 92.2%, the evaluation was "very good", the molding retention property (room temperature × 1 week) was 88.5%, the evaluation was "good", the 25% CLD was 1.073MPa, the compression residual strain was 3.7%, the evaluation was "very good", and the comprehensive evaluation was "good". In example 3, all evaluations were "good" or more, and the initial formability, the forming retention property, and the compressive residual strain were good, so that the hot compression forming was possible and the strain characteristics were good.

Example 4 is an example in which, in 65.9 parts by weight of the total of the crosslinking agent and the polyol component, 30 parts by weight of polyol 4(POP, solid content ratio of 43 wt%) as a polymer polyol was added, the content ratio of the polymer polyol in the polyurethane reaction composition was 19.8 wt%, the solid content ratio of the polymer polyol was 8.5 wt%, the addition ratio of the acid-modified polyethylene powder in the polyurethane reaction composition was 19.8 wt%, and the total resin ratio was 28.3 wt%. In example 4, the foam state was "very good", the initial moldability was 97.0%, the evaluation was "very good", the molding retention property (room temperature × 24h) was 96.8%, the evaluation was "very good", the molding retention property (room temperature × 1 week) was 95.2%, the evaluation was "very good", the 25% CLD was 0.669MPa, the compression residual strain was 3.1%, the evaluation was "very good", and the comprehensive evaluation was "very good". In example 4, all of them were evaluated as ". circinata", and the initial formability, the forming retention property, and the compressive residual strain were all good, so that the hot compression forming was possible and the strain characteristics were good.

Example 5 is an example in which the value of the total resin proportion was made almost the same as 28.4 wt% of example 4, and the proportion of the polymer polyol to the acid-modified polyethylene powder was changed. In example 5, of 65.9 parts by weight in total of the crosslinking agent and the polyol component, polyol 4(POP, solid content ratio of 43 wt%) as a polymer polyol was 10 parts by weight, and 40 parts by weight of the acid-modified polyethylene powder was added so that the content ratio of the polymer polyol in the polyurethane reaction composition was 6.6 wt%, the solid content ratio of the polymer polyol was 2.8 wt%, the addition ratio of the acid-modified polyethylene powder in the polyurethane reaction composition was 26.2 wt%, and the total resin ratio was 29.0 wt%. In example 5, the foam state was "very good", the initial moldability was 97.1%, the evaluation was "very good", the molding retention property (room temperature × 24h) was 98.1%, the evaluation was "very good", the molding retention property (room temperature × 1 week) was 97.2%, the evaluation was "very good", the 25% CLD was 0.550MPa, the compression residual strain was 3.6%, the evaluation was "very good", and the comprehensive evaluation was "very good". In example 5, all the test pieces were evaluated as ". circinata", and the initial formability, the forming retention property, and the compressive residual strain were all good, so that the hot compression forming was possible and the strain characteristics were good.

Example 6 is an example in which the acid-modified polyethylene powder was increased to 50 parts by weight so that the content ratio of the polymer polyol (polyol 4, solid content ratio of 43 wt%) in the polyurethane reaction composition was 6.3 wt%, the solid content ratio of the polymer polyol was 2.7 wt%, the addition ratio of the acid-modified polyethylene powder in the polyurethane reaction composition was 31.3 wt%, and the total resin ratio was 34.0 wt%. In example 6, the foam state was "very good", the initial moldability was 97.7%, the evaluation was "very good", the molding retention property (room temperature × 24h) was 98.8%, the evaluation was "very good", the molding retention property (room temperature × 1 week) was 97.9%, the evaluation was "very good", the 25% CLD was 0.405MPa, the compressive residual strain was 4.6%, the evaluation was "very good", and the comprehensive evaluation was "very good". In example 6, all the test pieces were evaluated as ". circinata", and the initial formability, the forming retention property, and the compressive residual strain were all good, so that the hot compression forming was possible and the strain characteristics were good.

Example 7 is an example in which the content ratio of the polymer polyol (polyol 4, solid content ratio 43 wt%) in the polyurethane reaction composition was 26.6 wt%, the solid content ratio of the polymer polyol was 11.4 wt%, the addition ratio of the acid-modified polypropylene powder in the polyurethane reaction composition was 6.6 wt%, and the total resin ratio was 18.0 wt%, in the same manner as in example 3, except that the acid-modified polypropylene was added instead of the acid-modified polyethylene. In example 7, the foam state was "very good", the initial moldability was 94.2%, the evaluation was "very good", the molding retention property (room temperature × 24h) was 91.5%, the evaluation was "very good", the molding retention property (room temperature × 1 week) was 87.2%, the evaluation was "good", the 25% CLD was 1.082MPa, the compression residual strain was 3.8%, the evaluation was "very good", and the comprehensive evaluation was "good". In example 7, all evaluations were "good" or more, and the initial formability, the forming retention property, and the compressive residual strain were good, so that the hot compression forming was possible and the strain characteristics were good.

Example 8 is an example in which polyol 3(POP, solid content ratio of 20 wt%) as a polymer polyol was 30 parts by weight, 30 parts by weight of an acid-modified polyethylene powder was added as a thermoplastic resin powder in 65.9 parts by weight in total of a crosslinking agent and a polyol component, the content ratio of the polymer polyol in the polyurethane reaction composition was 19.8 wt%, the solid content ratio of the polymer polyol was 4.0 wt%, the addition ratio of the acid-modified polyethylene powder in the polyurethane reaction composition was 19.8 wt%, and the total resin ratio was 23.8 wt%. In example 8, the foam state was "excellent", the initial moldability was 89.8%, the evaluation was "good", the molding retention property (room temperature × 24h) was 75.4%, the evaluation was "good", the molding retention property (room temperature × 1 week) was 73.6%, the evaluation was "good", the 25% CLD was 0.187MPa, the compression residual strain was 4.8%, the evaluation was "excellent", and the comprehensive evaluation was "good". In example 8, all evaluations were "good" or more, and the initial formability, the forming retention property, and the compressive residual strain were good, so that the hot compression forming was possible and the strain characteristics were good.

Example 9 is an example in which, in 65.9 parts by weight of the total of the crosslinking agent and the polyol component, the polymer polyol, polyol 3(POP, solid content ratio of 20 wt%) was 40 parts by weight, the polymer polyol content in the polyurethane reaction composition was 26.6 wt%, the polymer polyol solid content was 5.3 wt%, the acid-modified polyethylene powder addition ratio in the polyurethane reaction composition was 19.9 wt%, and the total resin ratio was 25.2 wt%. In example 9, the foam state was "excellent", the initial moldability was 89.6%, the evaluation was "good", the molding retention property (room temperature × 24h) was 81.2%, the evaluation was "good", the molding retention property (room temperature × 1 week) was 80.8%, the evaluation was "good", the 25% CLD was 0.212MPa, the compression residual strain was 4.5%, the evaluation was "excellent", and the comprehensive evaluation was "good". In example 9, all evaluations were "good" or more, and the initial formability, the forming retention property, and the compressive residual strain were good, so that the hot compression forming was possible and the strain characteristics were good.

Example 10 is an example in which the acid-modified polyethylene powder was added in an amount of 40 parts by weight, the content of the polymer polyol (polyol 3, solid content ratio of 20 wt%) in the polyurethane reaction composition was 18.6 wt%, the solid content of the polymer polyol was 3.7 wt%, the acid-modified polyethylene powder was added in an amount of 24.8 wt%, and the total resin ratio was 28.5 wt%. In example 10, the foam state was "excellent", the initial formability was 96.2%, the evaluation was "excellent", the forming retention property (normal temperature × 24h) was 90.1%, the evaluation was "excellent", the forming retention property (normal temperature × 1 h) was 88.9%, the evaluation was "good", the 25% CLD was 0.183MPa, the compression residual strain was 5.5%, the evaluation was "good", and the comprehensive evaluation was "good". In example 10, all evaluations were "good" or more, and the initial formability, the forming retention property, and the compressive residual strain were good, so that the hot compression forming was possible and the strain characteristics were good.

Example 11 is an example in which the acid-modified polyethylene powder was added in an amount of 40 parts by weight, the content of the polymer polyol (polyol 3, solid content ratio of 20 wt%) in the polyurethane reaction composition was 24.9 wt%, the solid content of the polymer polyol (polyol 3, solid content ratio of 20 wt%) was 5.0 wt%, the acid-modified polyethylene powder was added in an amount of 24.9 wt%, and the total resin content was 29.9 wt%. In example 11, the foam state was "very good", the initial moldability was 90.2%, the evaluation was "very good", the molding retention property (room temperature × 24h) was 87.5%, the evaluation was "good", the molding retention property (room temperature × 1 week) was 86.1%, the evaluation was "good", the 25% CLD was 0.240Pa, the compression residual strain was 3.3%, the evaluation was "very good", and the comprehensive evaluation was "good". In example 10, all evaluations were "good" or more, and the initial formability, the forming retention property, and the compressive residual strain were good, so that the hot compression forming was possible and the strain characteristics were good.

Example 12 is an example in which, out of 65.9 parts by weight of the total of the crosslinking agent and the polyol component, 30 parts by weight of polyol 5(POP, solid content ratio of 40 wt%) as a polymer polyol was added, 30 parts by weight of acid-modified polyethylene powder was added as a thermoplastic resin powder, the content ratio of the polymer polyol in the polyurethane reaction composition was 19.8 wt%, the solid content ratio of the polymer polyol was 7.9 wt%, the addition ratio of the acid-modified polyethylene powder in the polyurethane reaction composition was 19.8 wt%, and the total resin ratio was 27.7 wt%. In example 12, the foam state was "very good", the initial moldability was 97.6%, the evaluation was "very good", the molding retention property (room temperature × 24h) was 91.5%, the evaluation was "very good", the molding retention property (room temperature × 1 week) was 82.6%, the evaluation was "good", the 25% CLD was 0.139MPa, the compression residual strain was 5.7%, the evaluation was "good", and the comprehensive evaluation was "good". In example 12, all evaluations were "good" or more, and the initial formability, the forming retention property, and the compressive residual strain were good, so that the hot compression forming was possible and the strain characteristics were good.

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

The surface state was evaluated as "x" when the surface of the polyurethane foam after preliminary heating was visually observed, and as "excellent" when the surface was not burned or roughened and the surface state was smooth.

Regarding the molding retention, the thickness of the molded article was measured at each time immediately after the hot compression molding, after 1 day, and after 1 week, and the molding retention (%) was calculated by the following equation, and evaluated as "x" in the case where the calculated molding retention (%) was less than 50%, as "Δ" in the case where 50% to less than 70%, as "good" in the case where 70% to less than 90%, and as "excellent" in the case where 90% to 100%.

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

Example 4-1 is an example in which the preheating temperature is 190 ℃ and the preheating time is 3 minutes, the surface state is "excellent", the molding retention after forming is "excellent", the molding retention after 1 day is "good", the molding retention after 1 week is "good", and the surface state and the molding retention (formability) are both good.

Example 4-2 is an example in which the preheating temperature was 200 ℃ and the preheating time was 3 minutes, the surface state was "excellent", the molding retention immediately after molding was "excellent", the molding retention after 1 day was "good", the molding retention after 1 week was "good", and both the surface state and the molding retention (moldability) were good.

Example 4-3 is an example in which the preheating temperature was 210 ℃ and the preheating time was 3 minutes, and the surface state was "excellent", the molding retention immediately after molding was "excellent", the molding retention after 1 day was "excellent", the molding retention after 1 week was "excellent", and both the surface state and the molding retention (moldability) were the best.

Comparative example 4-1 was an example in which the preheating temperature was 220 ℃ and the preheating time was 3 minutes, the surface state was "x", the molding retention immediately after molding was "excellent", the molding retention after 1 day was "excellent", the molding retention after 1 week was "excellent", and the surface state was poor because the preheating temperature was too high.

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

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

Comparative example 4-3 was an example in which the preheating temperature was 150 ℃ and the preheating time was 5 minutes, the surface state was "excellent", the molding retention immediately after molding was "excellent", the molding retention after 1 day was "Δ", the molding retention after 1 week was "Δ", and the preheating temperature was too low, so that the molding retention (moldability) was poor.

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

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

Thus, the polyurethane foam of the present invention can be thermally compression molded and has good strain characteristics. The molded article of the polyurethane foam of the present invention can maintain the surface roughness of the molded article formed by the thermocompression molding and has good strain characteristics. Further, the process for producing a molded article of a polyurethane foam of the present invention can provide a molded article having good strain characteristics, which can maintain the unevenness of the surface of a sheet to be shaped by thermocompression molding, has a flat state with no surface burn and good roughness, and has good moldability retention (moldability).

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

In addition, the present application is based on japanese patent application filed on 10/2019 (japanese patent application 2019-. Further, the entire referenced disclosures cited therein are incorporated in their entirety into the present application.

Description of the reference numerals

10 polyurethane foam molded body

101. 103 recess

102. 104, 106 convex part

107 general portion without concavities and convexities

Claims

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

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

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 content 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 any one of claims 1 to 3, wherein the polyurethane foam has a foam strength based on JIS K6401: 2011 has a compression residual strain of 10% or less.

5. A molded article of a polyurethane foam having unevenness shaped 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 body having irregularities shaped by thermocompression molding on a surface of a sheet of a polyurethane foam, comprising:

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

and performing thermal compression molding by compression-pressing the preheated sheet using a normal-temperature mold having a mold surface provided with irregularities, and shaping the irregularities of the mold surface on the surface of the sheet.

7. The method for producing a formed body according to claim 6, wherein a compression ratio of the sheet by the compression pressing is 25 to 75%.