AU2018340584A1

AU2018340584A1 - Polyurethane composites

Info

Publication number: AU2018340584A1
Application number: AU2018340584A
Authority: AU
Inventors: Xue Dong Li; Zhen Yu QIAN; Jian Feng XU; Yang Chun ZHOU
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2017-09-29
Filing date: 2018-09-12
Publication date: 2020-04-16
Also published as: CN111183166B; KR20200062302A; WO2019063294A1; CN111183166A

Abstract

The invention relates to a polyurethane composition, comprising: (1) an isocyanate; and (2) an isocyanate reactive compound; wherein the isocyanate comprises 2,2'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate, and the amount of 2,2'-diphenylmethane diisocyanate is in the range of 10-100wt% based on the total weight of 2,2'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate.The invention also relates to a polyurethane composite comprising said polyurethane composition and a reinforcing material, and an article produced from said polyurethane composite.

Description

Polyurethane Composites

Technical field

The present invention relates to a polyurethane composition, a polyurethane composite comprising said polyurethane composition and a reinforced material, and an article produced from said polyurethane composite.

Background of art

Polyurethane (PU) composites are nowadays used in many applications because of their broad properties. Particularly, polyurethane composites exhibit excellent performance and unique advantages in pultrusion process compared with the traditional structure materials such as concrete, steel, aluminum, and conventional thermosetting resins.

The pultrusion process is a continuous process for producing fiber-reinforced profiles, wherein the fibers are impregnated by polyurethane composition in an open bath or in a closed injection box, and then shaped and hardened. Although polyurethane has various advantages, its relatively short processing time makes it challenging to produce large size parts by pultrusion process, such as bridge components, large artificial wood, large pole structure, complex window profile, reefer container, etc.

CN104045806A discloses a polyurethane composition for preparing a polyurethane composite, comprising: a) a polyisocyanate component, wherein the polyisocyanate component comprises 2,2'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate; and b) an isocyanate reactive component.

US2013/0309924A1 discloses a reinforced pultruded polyurethane obtainable via reacting A) polyether polyols, B) epoxides with C) organic polyisocyanates.

US8,663,414B2 discloses a pultrusion resin system, comprising a) a di- or polyisocyanate, b) a compound having at least two groups reactive toward an isocyanate, c) a catalyst, d) a polybasic acid having a functionality greater than or equal to 2 and, optionally, e) a further auxiliary or additive, where a boiling point of the polybasic acid is at least 200°C at standard pressure and the polybasic acid is soluble in the compound having at least two groups reactive toward an isocyanate.

However, there is still a need to find a polyurethane composition having relatively long processing time to allow the production of larger size parts.

Invention summary

Thus, the present invention provides a polyurethane composition, comprising:

(1) an isocyanate; and (2) an isocyanate reactive compound;

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PCT/EP2018/074631 wherein the isocyanate comprises 2,2'-diphenylmethane diisocyanate (2,2’-MDI) and 2,4'diphenylmethane diisocyanate (2,4’-MDI), and the amount of 2,2'-diphenylmethane diisocyanate is in the range of 10-100wt% based on the total weight of 2,2'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate.

The present invention provides a polyurethane composite, comprising:

(1) a polyurethane composition above; and (2) a reinforcing material.

The present invention also provides an article produced from said polyurethane composite above.

The polyurethane compositions of the present invention have prolonged gel time such that the polyurethane compositions are particularly suitable for producing large size parts such as bridge components, large artificial wood, large pole structure, complex window profile, reefer container, etc.

Embodiments

In one embodiment of the invention, a polyurethane composition is provided, wherein the polyurethane composition comprises: (1) an isocyanate; and (2) an isocyanate reactive compound; wherein the isocyanate comprises 2,2'-diphenylmethane diisocyanate and 2,4'diphenylmethane diisocyanate, and the amount of 2,2'-diphenylmethane diisocyanate is in the range of 10-100wt%, preferably 15-70wt%, more preferably 20-50wt%, still more preferably 2030wt% based on the total weight of 2,2'-diphenylmethane diisocyanate and 2,4'diphenylmethane diisocyanate.

In the polyurethane composition, the total amount of 2,2'-diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate is in the range of 50-100wt%, preferably 60-90wt%, more preferably 60-80wt% based on the total weight of the isocyanate.

The polyurethane composition can be compact or foam. In one embodiment of the invention, the polyurethane composition has a free rise density of from 30g/l to 900g/l.

The isocyanate can comprise the mixtures of monomeric diphenylmethane diisocyanates and of diphenylmethane diisocyanate homologs having a greater number of rings (polymeric MDI), tolylene diisocyanate (TDI), for example tolylene diisoyanate isomers such as tolylene 2,4- or 2,6-diisocyanate, or a mixture of these, naphthylene diisocyanate (NDI), or a mixture thereof, preferably 2,2'-diphenylmethane diisocyanate, 2,4'-diphenylmethane diisocyanate, 4,4'diphenylmethane diisocyanate (4,4'-MDI), polymeric MDI, or combination thereof.

The isocyanate reactive compound, also termed “polyols” for the purposes of this invention, can comprise any of the compounds having at least two groups reactive toward isocyanates, examples being OH, SH, NH, NH2, -COON, and CH-acidic groups.

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Isocyanate reactive compounds are known to the person skilled in the art and are described byway of example in “Kunststoffhandbuch, 7, Polyurethane” [Plastics Handbook, 7, Polyurethanes] Carl Hanser-Verlag, 3rd edition, 1993, chapter 3.1. Examples of the isocyanate reactive compounds are polyetherols or polyesterols. The isocyanate reactive compounds can be polyetherols or polyesterols comprising secondary OH groups, an example being polypropylene oxide. The functionality of these polyetherols or polyesterols is preferably from 2 to 4, particularly preferably from 2 to 3.

It is usual to use polyetherols and/or polyesterols having from 2 to 8 hydrogen atoms reactive toward isocyanate, and to use low-molecular-weight polyols, such as glycerol, dipropylene glycol, and/or tripropylene glycol. The OH number of these compounds is usually in the range from 30 to 2000 mg KOH/g, preferably in the range from 40 to 1000 mg KOH/g. The average OH number of all of the isocyanate reactive compound used here having at least two groups reactive toward isocyanates is from 100 to 1000 mg KOH/g, preferably from 300 to 900 mg KOH/g.

The polyetherols are obtained by known processes, for example via anionic polymerization of alkylene oxides with addition of at least one starter molecule comprising from 2 to 8, preferably from 2 to 6, and particularly preferably from 2 to 4, reactive hydrogen atoms, in the presence of catalysts. Catalysts used can comprise alkali metal hydroxides, such as sodium hydroxide or potassium hydroxide, or alkali metal alcoholates, such as sodium methoxide, sodium ethoxide, potassium ethoxide, or potassium isopropoxide, or, in the case of cationic polymerization, Lewis acids, such as antimony pentachloride, boron trifluoride etherate, or bleaching earth. Other catalysts that can be used are double-metal cyanide compounds, known as DMC catalysts.

The alkylene oxides used preferably comprise one or more compounds having from 2 to 4 carbon atoms in the alkylene moiety, e.g. tetrahydrofuran, ethylene oxide, propylene 1,2-oxide, butylene 1,2-oxide or butylene 2,3-oxide, in each case alone or in the form of a mixture, and preferably propylene 1,2-oxide and/or ethylene oxide, in particular propylene 1,2-oxide.

Examples of starter molecules that can be used are ethylene glycol, diethylene glycol, glycerol, trimethylolpropane, pentaerythritol, sugar derivatives, such as sucrose, hexitol derivatives, such as sorbitol, methylamine, ethylamine, isopropylamine, butylamine, benzylamine, aniline, toluidine, toluenediamine, naphthylamine, ethylenediamine, diethylenetriamine, 4,4'methylenedianiline, 1,3-propanediamine, 1,6-hexanediamine, ethanolamine, diethanolamine, triethanolamine, and also other di- or polyhydric alcohols, or di- or polybasic amines.

The polyester alcohols used are mostly produced via condensation of polyhydric alcohols having from 2 to 12 carbon atoms, e.g. ethylene glycol, diethylene glycol, butanediol, trimethylolpropane, glycerol, or pentaerythritol, with polybasic carboxylic acids having from 2 to 12 carWO 2019/063294

PCT/EP2018/074631 bon atoms, e.g. succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, and the isomers of naphthalenedicarboxylic acids, or their anhydrides.

Other starting materials that can also be used concomitantly in producing the polyesters are hydrophobic substances. The hydrophobic substances are substances insoluble in water which comprise a nonpolar organic moiety, and which also have at least one reactive group selected from hydroxy, carboxylic acid, carboxylic ester, or a mixture thereof. The equivalent weight of the hydrophobic materials is preferably from 130 to 1000 g/mol. Examples of materials that can be used are fatty acids, such as stearic acid, oleic acid, palmitic acid, lauric acid, or linoleic acid, and also fats and oils, e.g. castor oil, maize oil, sunflower oil, soybean oil, coconut oil, olive oil, or tall oil. If polyesters comprise hydrophobic substances, the proportion of the hydrophobic substances, based on the total monomer content of the polyester alcohol, is preferably from 1 to 30 mol %, particularly preferably from 4 to 15 mol %.

The functionality of the polyesterols used is preferably from 1.5 to 5, particularly preferably from 1.8 to 3.5.

In one particularly preferred embodiment, the isocyanate-reactive compounds comprise polyetherols, in particular exclusively polyetherols. The actual average functionality of the polyetherols is preferably from 2 to 4, particularly preferably from 2.5 to 3.5, in particular from 2.8 to 3.2, and their OH number is preferably from 300 to 900 mg KOH/g, and their content of secondary OH groups is preferably at least 50%, with preference at least 60%, with particular preference at least 70% and in particular at least 80%. The polyetherol used here preferably comprises polyetherol based on glycerol as starter and on propylene-1,2-oxide.

The polyurethane composition can further comprise additives. Said additives can comprise any of the auxiliaries and additives known for producing polyurethanes. Examples that may be mentioned are surfactant, release agents, coupling agents, fillers, dyes, pigments, flame retardants, hydrolysis stabilizers, viscosity reducers, water scavengers, antifoaming agents, and also substances having fungistatic and bacteriostatic action. Substances of this type are known and are described by way of example in “Kunststoffhandbuch, Band 7, Polyurethane” [Plastics Handbook, volume 7, Polyurethanes] Carl HanserVerlag, 3rd edition 1993, chapter 3.4.4 and 3.4.6 to 3.4.11.

Examples of viscosity reducers that can be used are y-butyrolactone, propylene carbonate, and also reactive diluents, such as dipropylene glycol, diethylene glycol, and tripropylene glycol.

Coupling agents that can be used comprise silanes, such as isocyanate silanes, epoxysilanes, or aminosilanes. Substances of this type are described by way of example in E. P. PluedWO 2019/063294

PCT/EP2018/074631 demann, Silane Coupling Agents, 2nd ed., Plenum Press, New York, 1991 and in K. L. Mittal, ed., Silanes and Other Coupling Agents, VSP, Utrecht, 1992.

Release agents that can be used are any of the conventional release agents used in producing polyurethanes, examples being long-chain carboxylic acids, in particular fatty acids, such as stearic acid, amines of long-chain carboxylic acids, e.g. stearamide, fatty acid esters, metal salts of long-chain carboxylic acids, e.g. zinc stearate, or silicones. Particularly suitable materials are the internal release agents obtainable specifically for the pultrusion process, e.g. from Axel Plastics or Technick Products. The internal release agents from Technick Products probably comprise phosphoric acid and fatty acids. The internal release agents from Axel Plastics probably comprise fatty acids.

In one embodiment of the present invention, the molar ratio of the isocyanate reactive compound to the isocyanate is in the range of 1:0.5 to 1:2.

Polyurethane composites are also provided, wherein the polyurethane composite comprises:

(1) a polyurethane composition above; and (2) a reinforcing material.

Preferably, the reinforcing material is a fiber material. The fiber material used can comprise any of the types of continuous-filament fibers. Continuous-filament fiber here means a fiber material the length of which is at least a plurality of meters. These materials are by way of example unwound from rolls. The fiber material used here can comprise individual fibers, known as fiber rovings, braided fibers, fiber mats, fiber scrims, and woven fibers. Particularly in the case of fiber composites, such as braided fibers, twisted fibers, fiber scrims, or woven fibers, there can also be shorter individual fibers comprised within the individual fibers comprised within said fiber structures. It is preferable that the fiber material comprises or is composed of glass fiber, glass mats, carbon fiber, polyester fiber, natural fiber, aramid fiber, basalt fiber, or nylon fiber, and it is particularly preferable to use carbon fibers or glass fibers.

In one embodiment of the present invention, the weight ratio of the polyurethane composition to the reinforcing material is in the range of 10:90 to 70:30, preferably 15:85 to 50:50, more preferably 18:82 to 30:70.

In general, the polyurethane composites are prepared by mixing components of the polyurethane composition to give a polyurethane reaction mixture, and then impregnating the reinforcing material with the resultant reaction mixture.

The present invention also provides an article produced from a polyurethane composite above by pultrusion.

In one embodiment of the present invention, the articles are bridge components, large artificial wood, large pole structure, complex window profile, reefer container.

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Examples

The present invention is now further illustrated by reference to the following examples, however, the examples are used for the purpose of explanation and not intended to limit the scopes of the present invention.

All materials used in the examples are available in the market, and their amounts used are listed in Table 1.

Comparative example 1

Component A and component B are mixed for 1 min using SpeedMixer available from FlackTek Inc. at 25°C. Then, gel time is measured by gel timer available from SHYODU INSTRUMENT COMPANY.

In addition, PU panel sample is prepared by mixing component A and component B for 1 min using SpeedMixer at 25°C, and vacuum pumping for 7 min at 70°C and placing for 8 min at 70°C, then curing for 1 h at 150°C.

Comparative example 2

Comparative example 2 are carried out by same procedure as comparative example 1 except that the amounts of 2,2’-MDI and 2,4’-MDI and their ratio vary.

Examples 1-5

Examples 1-5 are carried out by same procedure as comparative example 1 according to the components and amounts listed in Table 1.

The pure PU resin’s mechanical properties of Comparative example 1, Examples 1-3 are listed in Table 2. The preparation of PU panel sample can be referred to Comparative example

1.

In addition, glass fiber reinforced PU composite is prepared using a mixture of glass fiber and sample from Example 1 by pultrusion process, wherein the content of glass fiber is 80wt% based on the weight of the PU composite. The measured result is shown in Table 3.

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Table 1: Components and properties of polyurethane composition

LO ω CL E 05 X LB	Elastocoat CC6226/103 CA (47g)	009	Isocyanate? (53g)	45	29.4	36.9	14.4	1/0.39	19.3	1.22	00	42
^r ω CL E 05 X LB	Elastocoat CC6226/103 CA (47g)	009	Isocyanate6 (53g)	45	29.4	21.8	29.5	1/1.35	19.3	1.22	78	42
CO ω CL E 05 X LB	Elastocoat CC6226/103 CA (47g)	009	Isocyanate5 (53g)	30	17.6	17.1	52.4	1/3.1	12.9	1.22	94	42
CM ω CL E 05 X LB	Elastocoat CC6226/103 CA (47g)	009	Isocyanate4 (53g)	35	23.5	14.6	45.3	1/3.1	16.6	1.22	76	T~
ω CL E 05 X LB	Elastocoat CC6226/103 CA (47g)	009	Isocyanate3 (53g)	45	29.4	12.2	38.2	1/3.1	20.2	1.22	63	T~
Comparative Example 2	Elastocoat CC6226/103 CA (48g)	009	Isocyanate2 (52g)	20	5.9	2.4	46.8	1/20	40.8	1.22	00 co	42
Comparative Example 1	Elastocoat CC6226/103 CA (46g)	009	Isocyanatel (54g)	45	29.4	GOO	25.8	1/516	44.75	1.22	37	40
	Component A	Viscosity of Component A (mPa.s)	Component B	Viscosity of Component B (mPa.s)	Wt% of Polymeric-MDI in Component B	Wt% of2,2’-MDI in Component B	Wt% of2,4’-MDI in Component B	Wt ratio of 2,2’-MDI/2,4’MDI	Wt% of4,4’-MDI in Component B	Isocyanate index	Gel time at room temperature (min)	Curing Time (s) @200°C

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Table 1 shows that the gel times of Example 1-3 are significantly greater than that of Comparative example 1 and Comparative example 2, even about 2 times or above of the gel time of Comparative example 1 and Comparative example 2, which indicates that appropriate amount of 2,2’-MDI based on the total amount of 2,2’-MDI and 2,4’-MDI used is important to prolong the 5 processing time. Furthermore, the prolonging of the gel time does not compromise its curing speed. Example 1, Example 4 and Example 5 show that the gel times become longer with the ratio of 2,2’-MDI/2,4’-MDI increasing even if the total amount of 2,2’-MDI and 2,4’-MDI is about same.

Physical properties of PU panel samples prepared from polyurethane compositions are 10 measured as shown in table 2.

Table 2: Physical properties of PU panel samples

Properties	Testing methods	Comparative Example 1	Example 1	Example 2	Example 3
Tensile strength (MPa)	ISO 527	76	77	76	77
Elongation (%)	ISO 527	4.7	4.6	4.9	4.8
E-modulus (MPa)	ISO 527	3230	3223	3150	3160
Flexural strength (MPa)	ISO 178	92	94	93	92
Flexural modulus (MPa)	ISO 178	1905	1920	1895	1910
Hardness (Shore D)	ISO 7619-1	85±5	85±5	85±5	85±5
Tg (°C)	DMA	82	82	81	81

In Table 2, the physical performances of PU panel samples of Example 1-3 are comparable to Comparative example 1, which indicates that the prolonging of the gel time does not compromise its physical performances.

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Table 3: Physical properties of PU composite samples prepared via pultrusion

Properties	Testing methods	Example 1
Tensile Strength (MPa)	GB/T 1447	1120
E-modulus (GPa)	GB/T 1447	51
Flexural strength (MPa)	GB/T 1449	1450
Flexural modulus (GPa)	GB/T 1449	52
Longitudinal Shear Strength (MPa)	GB/T 1447	63
Transverse Shear Strength (MPa)	GB/T 1447	16.4
Hardness (Shore D)	ISO 7619-1	> 85
Heat Deformation Temperature(°C)	GB 1634	250

PU composite samples are prepared via pultrusion process by impregnating glass fiber (Owens Corning PS4100) with sample of example 1. The physical properties of the PU composites are excellent, as shown in Table 3, which are particularly suitable for producing large size composite parts, e.g. bridge components, large artificial wood, large pole structure, complex window profile, reefer container.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the present invention. Thus, it is intended that the present invention cover such modifications and variations as come within the scope of the appended claims and their equivalents.

Claims

Claims

1. A polyurethane composition, comprising:

(1) an isocyanate; and (2) an isocyanate reactive compound;

wherein the isocyanate comprises 2,2'-diphenylmethane diisocyanate and 2,4'diphenylmethane diisocyanate, and the amount of 2,2'-diphenylmethane diisocyanate is in the range of 10-100wt% based on the total weight of 2,2'-diphenylmethane diisocyanate and 2,4'diphenylmethane diisocyanate.
2. The polyurethane composition according to claim 1, wherein the total amount of 2,2'diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate is in the range of 50100wt%, preferably 60-90wt%, more preferably 60-80wt% based on the total weight of the isocyanate.
3. The polyurethane composition according to claim 1 or 2, wherein the molar ratio of the isocyanate reactive compound to the isocyanate is in the range of 1:0.5 to 1:2.
4. The polyurethane composition according to claim 1 or 2, wherein the isocyanate further comprises 2,4'-diphenylmethane diisocyanate, polymeric MDI, or combination thereof.
5. The polyurethane composition according to claim 1 or 2, wherein the amount of 2,2'diphenylmethane diisocyanate is in the range of 15-70wt% based on the total weight of 2,2'diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate.
6. The polyurethane composition according to claim 1 or 2, wherein the amount of 2,2'diphenylmethane diisocyanate is in the range of 20-50wt% based on the total weight of 2,2'diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate.
7. The polyurethane composition according to claim 1 or 2, wherein the amount of 2,2'diphenylmethane diisocyanate is in the range of 20-30wt% based on the total weight of 2,2'diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate.
8. The polyurethane composition according to claim 1 or 2, wherein the isocyanate reactive compound is selected from polyether polyol, polyester polyol and combination thereof.
9. The polyurethane composition according to claim 1 or 2, wherein the 2,2'diphenylmethane diisocyanate and 2,4'-diphenylmethane diisocyanate further react with polyols to form prepolymers.
10. The polyurethane composition according to claim 1 or 2, wherein the polyurethane composition is compact or foam.
11. The polyurethane composition according to claim 10, wherein the polyurethane composition has a free rise density of from 30g/l to 900g/L
12. A polyurethane composite, comprising:

(1) a polyurethane composition according to anyone of claims 1 to 11; and

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13. The polyurethane composite according to claim 12, wherein the reinforcing material is a fiber.
14. The polyurethane composite according to claim 13, wherein the reinforcing material is a 5 glass fiber.
15. The polyurethane composite according to any one of claims 11 to 14, wherein the weight ratio of the polyurethane composition to the reinforcing material is in the range of 10:90 to 70:30, preferably 15:85 to 50:50, more preferably 18:82 to 30:70.
16. An article produced from a polyurethane composite according to anyone of claims 11 to

10 15.
17. The article according to claim 16, wherein the articles are produced by pultrusion, filament winding, resin transfer molding, vacuum assisted resin infusion, hand lay up method, or resin injection molding.
18. The article according to claim 16 or 17, wherein the articles are bridge components, 15 large artificial wood, large pole structure, complex window profile, reefer container.