EP4469501A1

EP4469501A1 - A polyol composition

Info

Publication number: EP4469501A1
Application number: EP22922818.4A
Authority: EP
Inventors: Yongming GU; Pengfei Wu; Zhijiang Li
Original assignee: Covestro Deutschland AG
Current assignee: Covestro Deutschland AG
Priority date: 2022-01-28
Filing date: 2022-01-28
Publication date: 2024-12-04
Also published as: EP4469501A4; CN118591579A; WO2023141978A1

Abstract

The present invention relates to a polyol composition, a polyurethane reaction system, a polyurethane resin and a polyurethane composite.

Description

A polyol composition

Technical Field

The present invention relates to a polyol composition and a polyurethane reaction system comprising the polyol composition.
Background Technology
The polyurethane resin has many advantages over the unsaturated polyester resin, the epoxy resin and the vinyl resin in the preparation of pultrusion molded composites. For example, a higher pultrusion speed can be met, up to approximately 3 meters per minute. The surface quality of its product is relatively satisfactory, too. Compared to the unsaturated resin, it has low combustion smoke content, while also having excellent corrosion resistance. Because styrene monomers or other volatile substances are not used, it contains less organic volatile compound (VOC) and is more environmentally friendly. In addition, the polyurethane pultrusion composite can also have higher fiber content, high fiber direction tensile strength and high transverse mechanical strength, high impact strength, high abrasion resistance, high rigidity, high product complexity, lower product wall thickness, and high screw pulling strength and the like.
However, one of the greatest challenges for the pultrusion molded polyurethane composite is that it is difficult for the final product to meet the flame retardant requirements in the vertical burning state, especially the requirement of conforming to IEC 60695-11-10: 2013. Meanwhile, the pultrusion molded polyurethane composite, especially the pultrusion molded aromatic polyurethane composite is prone to the surface resin pulverization under the outdoor long-term solarization conditions, and therefore internal fibers are exposed. In order to improve the flame retardant property of the polyurethane composite, it is the general practice in the industry to add a coated red phosphorus or TCPP, however, both of which will cause many problems in the production process and have poor applicability. Because the coated red phosphorus is granular, it easily blocked the glue-injection pipeline and at the same time is hardly distributed uniformly in the composite; and TCPP is liquid and can be distributed uniformly in the composite, but a large smoke is generated in the production process, and the production requirements cannot be met.
CN105859998B discloses a composition for polyurethane foaming, a polyurethane foam and use thereof. The composition of the application comprises two different polyols with a polyethylene oxide ether structure and a polypropylene oxide ether structure, and a specific type of catalyst, flame retardant and water are added thereto; at the same time, the composition contains a small amount of a surfactant and other small molecular alcohols. The traits of the product are that it is pale yellow and transparent, and the product is not layered over long-term storage.
CN111499828A discloses a resin composition for a low density high flame retardant polyurethane material and an application thereof, wherein the composition is comprised of A-component and B-component, A-component: polyether polyol 1: 40-60 parts; polyether polyol 2: 10-20 parts; flame retardant polyether ester polyol: 10-30 parts; foam stabilizing agent: 0.5-2 parts; composite catalyst: 0.5-1.5 parts; chain extender: 5-10 parts; cross-linking agent: 1-5 parts; water: 1-5 parts; flame retardant: 1-5 parts; carbon black: 0.2-1 parts; for the polyether polyol 1, glycerol is used as the starter, propylene oxide is used as the polymerization units, and its functionality is 3; for the polyether polyol 2, pentaerythritol is used as the starter, the polyether polyol is chain-extended with propylene oxide and terminated with ethylene oxide, and has the functionality of 4; B-component: polymethylene polyphenylene polyisocyanate.
CN111333813A discloses a composition for rigid polyurethane foam, which is composed of the following components: 3-5 parts of polyether polyol A, 2-4 parts of polyether polyol B, 2-4 parts of polyester polyol C, 0.1-0.5 parts of foam stabilizing agent, 0.1-0.3 parts of cell-opener, 0.2-0.6 parts of catalyst, 0.2-1.0 parts of water, 1-3 parts of flame retardant.
Despite the foregoing disclosures, there is still an urgent need for a suitable polyol composition for safely and efficiently preparing high quality, high flame retardant polyurethane resins.
Summary of the Invention
In one aspect of the present invention, there is provided a polyol composition for preparation of a polyurethane composite, comprising:
B1) based on the total weight of the polyol composition, 30-60 wt%, preferably 35-55 wt%of an organic polyol, preferably a polyether polyol, having the functionality of 2-5, preferably 2-4 and the average weight-average molecular weight of ≤900 g/mol, preferably ≤800 g/mol, more preferably ≤750 g/mol (measured according to DIN55672-1: 2007) ;
B2) based on the total weight of the polyol composition, 0-30 wt%, preferably 5-25 wt%of a polyether polyol, having the functionality of 2-3 and the average weight-average molecular weight of ≥1200 g/mol, preferably ≥1500 g/mol, more preferably ≥2000 g/mol (measured according to DIN55672-1: 2007) ;
B3) at least one flame retardant comprising phosphorus and halogen;
wherein, the flame retardant has the phosphorus content of 2.7-10 wt%, preferably 3.5-8.3 wt%, based on the total weight of the polyol composition;
the flame retardant has the halogen content of 0.3-8.4 wt%, preferably 0.5-7 wt%, based on the total weight of the polyol composition;
wherein the polyol composition comprises less than 10 wt%, preferably less than 8.0 wt%, based on the total weight of the polyol composition, of solid filler and/or wherein the polyol composition comprises less than 1.0 wt%, preferably 0.50 wt%or less, more preferably 0.30 wt%or less, based on the total weight of the polyol composition, of foaming agent.
Preferably, the weight ratio of the content of phosphorus in the flame retardant to the content of halogen in the flame retardant is 0.6-33, preferably 0.8-16, more preferably 1.1-10.
Preferably, the flame retardant comprises at least one halogen-free phosphorus-containing flame retardant and at least one halogen-containing flame retardant. The halogen-containing flame retardant is preferably a chlorine-containing flame retardant. The halogen-free phosphorus-containing flame retardant refers to a flame retardant which does not contain halogen but contains phosphorus. The halogen-containing flame retardant refers to a flame retardant containing halogen.
Preferably, the weight ratio of the content of the halogen-free phosphorus-containing flame retardant to the content of the halogen-containing flame retardant is ≥0.8, preferably ≥1.0, and more preferably 1.1-10.
Preferably, the halogen-free phosphorus-containing flame retardant is selected from halogen-free phospho-acid esters, preferably tricresyl phosphate, diethyl ethylphosphonate (DEEP) , triethyl phosphate (TEP) , dimethyl propylphosphonate, dimethyl methylphosphonate (DMPP) , cresyl diphenyl phosphate (CDP) , triphenyl phosphate. The halogen-free phosphorus-containing flame retardant can also be selected from halogen-free phosphorus-containing polyols, preferably glycol bis (2-chloroethyl) phosphate, tris (polyoxyalkylene) phosphate, tris (polyoxyalkylene) phosphite, tri (dipropylene glycol) phosphite, tris (hydroxymethyl) phosphine oxide, or a combination thereof. The halogen-free phosphorus-containing flame retardant is more preferably triethyl phosphate, trimethyl phosphate, dimethyl methylphosphonate, tris (hydroxymethyl) phosphine oxide or a combination thereof, particularly preferably triethyl phosphate.
Preferably, the halogen-containing flame retardant is selected from halogen-containing phosphates, preferably tri (2-chloroethyl) phosphate, tri (2-chloropropyl) phosphate (TCPP) , tri (1, 3-dichloropropyl) phosphate or a combination thereof, more preferably tri (2-chloropropyl) phosphate, tri (1, 3-dichloropropyl) phosphate or a combination thereof, particularly preferably tri (2-chloropropyl) phosphate (TCPP) .
Preferably, the content of the halogen-free phosphorus-containing flame retardant is ≥50 wt%, preferably 50-95 wt%, based on the total weight of the flame retardant.
Preferably, the content of the flame retardant is 20-60 wt%, preferably 30-50 wt%, based on the total weight of the polyol composition.
Preferably, the polyol composition also comprises B4) at least one metal catalyst.
Preferably, the flame retardant is selected from a mixture of tri (2-chloropropyl) phosphate and triethyl phosphate, wherein the weight ratio of the content of triethyl phosphate to the content of tri (2-chloropropyl) phosphate is ≥0.8, preferably ≥1.0, more preferably 1.1-10.
Surprisingly, we have found that the polyol composition of the present invention comprising the flame retardant containing specific contents of halogen and phosphorus, the specific polyol, the polyether polyol and other components that are mutually adaptive can prepare the polyurethane resin and the polyurethane composite with high flame retardance, and the production process is good, particularly with a small amount of smoke at the mold outlet, so that the safety and comfort of the production line can be ensured, the production efficiency can be promoted, and the production is more environment-friendly. Especially when used for preparation of a polyurethane composite, the polyol composition can be used together with a solid filler, such as solid type flame retardant, in an amount of less than 10wt%, preferably less than 8 wt%, more preferably less than 5 wt%, based on the total weight of the polyol composition, most preferably without a filler. Usually, a solid filler can make the storage of the polyol composition more stable, but in the invention, having the selected proportion of abovementioned components, both stable storage and improve smoke circumstance are achieved.
In a further aspect of the present invention, there is provided a polyurethane reaction system, comprising:
Component A, comprising: at least one isocyanate;
Component B, comprising: the polyol composition of the present invention;
wherein the polyurethane reaction system comprises less than 10 wt%, preferably less than 8.0 wt%, based on the total weight of the polyol composition, of solid filler and/or wherein the polyurethane reaction system comprises less than 1.0 wt%, preferably 0.50 wt%or less, more preferably 0.30 wt%or less, based on the total weight of the polyol composition, of foaming agent.
Preferably, the isocyanate is selected from toluene diisocyanate, diphenylmethane diisocyanate, polyphenylmethane polyisocyanate, 1, 5-naphthalene diisocyanate, hexamethylene diisocyanate, methylcyclohexyl diisocyanate, 4, 4'-dicyclohexylmethane diisocyanate, isophorone diisocyanate, p-phenylene diisocyanate, p-xylylene diisocyanate, tetramethyldimethylene diisocyanate and their polymers, prepolymer, or a combination thereof.
Preferably, the isocyanate index of the polyurethane reaction system is 1.05-2.5, preferably 1.15-2.0, more preferably 1.2-1.8. We have surprisingly found that when the isocyanate index is in the aforementioned range, its flame retardant property is further improved.
Preferably, the flame retardant comprises at least one halogen-free phosphorus-containing flame retardant and at least one halogen-containing flame retardant.
Preferably, the halogen-free phosphorus-containing flame retardant is selected from halogen-free phospho-acid esters, preferably tricresyl phosphate, diethyl ethylphosphonate (DEEP) , triethyl phosphate (TEP) , dimethyl propylphosphonate (DMPP) , dimethyl methylphosphonate (DMPP) , cresyl diphenyl phosphate (DPK) , triphenyl phosphate. The halogen-free phosphorus-containing flame retardant can also be selected from halogen-free phosphorus-containing polyols, preferably glycol bis (2-chloroethyl) phosphate, tris (polyoxyalkylene) phosphate, tris (polyoxyalkylene) phosphite, tri (dipropylene glycol) phosphite, tris (hydroxymethyl) phosphine oxide, or a combination thereof. The halogen-free phosphorus-containing flame retardant is more preferably triethyl phosphate, trimethyl phosphate, dimethyl methylphosphonate, tris (hydroxymethyl) phosphine oxide or a combination thereof, particularly preferably triethyl phosphate.
Preferably, the halogen-containing flame retardant is selected from halogen-containing phosphates, preferably tri (2-chloroethyl) phosphate, tri (2-chloropropyl) phosphate (TCPP) , tri (1, 3-dichloropropyl) phosphate or a combination thereof, preferably tri (2-chloropropyl) phosphate, tri (1, 3-dichloropropyl) phosphate or a combination thereof, more preferably tri (2-chloropropyl) phosphate (TCPP) .
Preferably, the content of the halogen-free phosphorus-containing flame retardant is ≥50 wt%, preferably 50-95 wt%, further preferably 60-85 wt%, based on the total weight of the flame retardant.
Preferably, the content of the flame retardant is 20-60 wt%, preferably 25-55 wt%, more preferably 30-50 wt%, based on the total weight of the polyol composition.
Preferably, the flame retardant is a mixture of tri (2-chloropropyl) phosphate and triethyl phosphate.
Preferably, the polyurethane reaction system has a gel time at 25℃ of 15-90 minutes, preferably 20-70 minutes, more preferably 25-50 minutes.
A method for preparing a polyurethane resin, comprising reacting the inventive polyurethane reaction system, i.e., a polyurethane reaction system comprising the following components to obtain the polyurethane resin:
Component A, comprising: at least one isocyanate;
Component B, comprising: the polyol composition of the present invention;
wherein the polyurethane reaction system comprises less than 10 wt%, preferably less than 8.0 wt%, based on the total weight of the polyol composition, of solid filler and/or wherein the polyurethane reaction system comprises less than 1.0 wt%, preferably 0.50 wt%or less, more preferably 0.30 wt%or less, based on the total weight of the polyol composition, of foaming agent.
A method for preparing a polyurethane composite comprising:
providing the polyurethane reaction system of the present invention, which specifically comprises:
Component A, comprising: at least one isocyanate;
Component B, comprising: the polyol composition of the present invention, which specifically comprises:
B1) based on the total weight of the polyol composition, 30-60 wt%, preferably 35-55 wt%of an organic polyol, preferably a polyether polyol, having the functionality of 2-5, preferably 2-4 and the average weight-average molecular weight of ≤900 g/mol, preferably ≤800 g/mol, more preferably ≤750 g/mol (measured according to DIN55672-1: 2007) ;
B2) based on the total weight of the polyol composition, 0-30 wt%, preferably 5-25 wt%of a polyether polyol, having the functionality of 2-3 and the average weight-average molecular weight of ≥1200 g/mol, preferably ≥1500 g/mol, more preferably ≥2000 g/mol (measured according to DIN55672-1: 2007) ;
B3) at least one flame retardant comprising phosphorus and halogen; and,
Component C, at least one fiber-reinforced material;
wherein, the flame retardant has the phosphorus content of 2.7-10 wt%, preferably 3.5-8.3 wt%, based on the total weight of the polyol composition; and
the flame retardant has the halogen content of 0.3-8.4 wt%, preferably 0.5-7 wt%, based on the total weight of the polyol composition;
wherein the polyurethane reaction system comprises less than 10 wt%, preferably less than 8.0 wt%, based on the total weight of the polyol composition, of solid filler and/or wherein the polyurethane reaction system comprises less than 1.0 wt%, preferably 0.50 wt%or less, more preferably 0.30 wt%or less, based on the total weight of the polyol composition, of foaming agent;
bringing the polyurethane reaction system into contact with Component C; and
reacting the polyurethane reaction system.
Preferably, the method is selected from pultrusion process, winding molding process, hand lay-up molding process, spray molding process, heating dual-track continuous molding process, or a combination thereof.
The methods for preparing the polyurethane resin and the polyurethane composite of the present invention can prepare the polyurethane resin and the polyurethane composite with high flame retardance and satisfactory surface conditions from the polyol composition comprising the flame retardant containing specific contents of halogen and phosphorus, the polyol, the polyether polyol and other components that are mutually adaptive. Moreover, the production process is more optimized, particularly with a small amount of smoke at the mold outlet, so that the safety and comfort of the production line can be ensured, the production efficiency can be promoted, and the production is more environment-friendly.
In this invention, fiber-reinforced material refers to a material that plays a reinforcing role in composite materials. Specifically, fiber-reinforced material can be selected from glass fibers, aramid fibers, carbon fibers, natural fibers, metal fibers or a mixture thereof. Preferably the fiber-reinforced material is the glass fiber. The glass fiber can be used in the form of untwisted roving, untwisted roving fabric, glass fiber mat and glass fiber fabric.
In a further aspect of the present invention, there is provided a polyurethane composite prepared by the aforementioned method for preparing a polyurethane composite according to the present invention.
Preferably, the content of the fiber-reinforced material is 50-85 wt%, preferably 55-82 wt%, more preferably 72-80 wt%, based on the total weight of the polyurethane composite.
Preferably, the density of the polyurethane composite is 0.6-2.2 g/cm ³, preferably 1.2-2.1 g/cm ³, further preferably 1.7-2.1 g/cm ³.
Preferably, the content of phosphorus in the flame retardant in the polyurethane composite is 0.4-5 wt%, preferably 0.63-3.73 wt%, more preferably 0.7-2.32 wt%, based on the total mass of the polyurethane composite; the content of halogen in the flame retardant in the polyurethane composite is 0.045-4.2 wt%, preferably 0.09-3.15 wt%, more preferably 0.1-1.96 wt%, based on the total mass of the polyurethane composite.
Preferably, the total burning time for the polyurethane composite vertically burning in the fiber direction is ≤150 seconds, preferably ≤145 seconds, more preferably ≤130 seconds (with reference to IEC 60695-11-10: 2013 test method B: Vertical Burning Test) .
In a further aspect of the present invention, there is provided a polyurethane product comprising the polyurethane composite of the present invention. The polyurethane product of the present invention can be selected from: cable trays, frames of doors, windows and curtain walls, frames of ladders, tent poles or pipes, anti-glare shields, floors, sucker rods, telegraph poles and cross arms, guardrails, gratings, architectural sectional materials, container sectional materials and plates, bike racks, fishing rods, cable cores, insulator core rods, antenna housings, single-layer or sandwiched continuous plates, sleeper or sheets for producing main spars of the turbine fan blade.

Detailed description of the invention

In one aspect, the present invention provides a polyol composition comprising the following components:
B1) based on the total weight of the polyol composition, 30-60 wt%, preferably 35-55 wt%of an organic polyol, preferably a polyether polyol, having the functionality of 2-5, preferably 2-4 and the average weight-average molecular weight of ≤900 g/mol, preferably ≤800 g/mol, more preferably ≤750 g/mol (measured according to DIN55672-1: 2007) ;
B2) based on the total weight of the polyol composition, 0-30 wt%, preferably 5-25 wt%of a polyether polyol, having the functionality of 2-3 and the average weight-average molecular weight of ≥1200 g/mol, preferably ≥1500 g/mol, more preferably ≥2000 g/mol (measured according to DIN55672-1: 2007) ;
B3) at least one flame retardant comprising phosphorus and halogen;
wherein, the flame retardant has the phosphorus content of 2.7-10 wt%, preferably 3.5-8.3 wt%, based on the total weight of the polyol composition;
the flame retardant has the halogen content of 0.3-8.4 wt%, preferably 0.5-7 wt%, based on the total weight of the polyol composition;
wherein the polyol composition comprises less than 10 wt%, preferably less than 8.0 wt%, based on the total weight of the polyol composition, of solid filler and/or wherein the polyol composition comprises less than 1.0 wt%, preferably 0.50 wt%or less, more preferably 0.30 wt%or less, based on the total weight of the polyol composition, of foaming agent.
The present invention also provides a polyurethane reaction system comprising the aforementioned polyol composition and a polyisocyanate suitable thereto, and further provides a polyurethane composition comprising the polyurethane reaction system and a fiber-reinforced material, the corresponding methods for preparing a polyurethane resin and a polyurethane composite, and the prepared polyurethane resin and the prepared polyurethane composite and the like.
In an embodiment of the present invention, the organic polyisocyanate may be represented by a general formula R (NCO) _n, wherein R represents an aliphatic hydrocarbon group having 2-18 carbon atoms, an aromatic hydrocarbon group having 6-15 carbon atoms or an araliphatic hydrocarbon group having 8-15 carbon atoms, and n is an integral number of 2-4.
The example of the organic polyisocyanate includes, but is not limited to diphenylmethane-4, 4'-diisocyanate, diphenylmethane-2, 4'-diisocyanate, diphenylmethane-2, 2'-diisocyanate, ethylene diisocyanate, tetramethylene 1, 4-diisocyanate, hexamethylene diisocyanate (HDI) , dodecylene 1, 2-diisocyanate, cyclobutane-1, 3-diisocyanate, cyclohexane-1, 3-diisocyanate, cyclohexane-1, 4-diisocyanate, 1-isocyanato-3, 3, 5-trimethyl-5-isocyanatomethylcyclohexane, hexahydrotoluene-2, 4-diisocyanate, hexahydrophenyl-1, 3-diisocyanate, hexahydrophenyl-1, 4-diisocyanate, perhydro-diphenylmethane-2, 4-diisocyanate, perhydro-diphenylmethane-4, 4-diisocyanate, phenylene-1, 3-diisocyanate, phenylene-1, 4-diisocyanate, durene-1, 4-diisocyanate, stilbene-1, 4-diisocyanate, 3, 3-dimethyl-4, 4-diphenyldiisocyanate, toluene-2, 4-diisocyanate, toluene-2, 6-diisocyanate, or a mixture of the above-mentioned polyisocyanates, or isomers of the above-mentioned polyisocyanates, or a mixture of the above-mentioned polyisocyanates and isomers thereof. Diphenylmethane-4, 4'-diisocyanate, diphenylmethane-2, 4'-diisocyanate, diphenylmethane-2, 2'-diisocyanate, toluene-2, 4-diisocyanate, toluene-2, 6-diisocyanate, or a mixture thereof is preferred. Particular preference is given to diphenylmethane-4, 4'-diisocyanate, diphenylmethane-2, 4'-diisocyanate or diphenylmethane-2, 2'-diisocyanate.
The organic polyisocyanate can also comprise polyisocyanates obtained by modification with a carbodiimide, an allophanate or an isocyanate. Its example includes, but is not limited to diphenylmethane diisocyanate, diphenylmethane diisocyanate modified with carbodiimide, or their isomers, or a mixture of the above-mentioned modified polyisocyanate and an isomer thereof.
The polyol that can be used in the present invention can be an organic polyol conventionally used in the art for preparing a polyurethane, and comprises, but is not limited to: a polyether polyol, a polyether carbonate polyol, a polyester polyol, a polycarbonate diol, a polymeric polyol, a vegetable oil-based polyol or a combination thereof.
The polyether polyol can be prepared by known processes, for example, obtained by reacting an alkylene oxide with an starter in the presence of a catalyst. The catalyst is preferably, but not limited to, an alkaline hydroxide, an alkaline alkoxide, antimony pentachloride, boron fluoride etherate, or a mixture thereof. The alkylene oxide is preferably, but not limited to, tetrahydrofuran, ethylene oxide, propylene oxide, 1, 2-butylene oxide, 2, 3-butylene oxide, styrene oxide or a mixture thereof, particularly preferably ethylene oxide and/or propylene oxide. The starter is preferably, but not limited to, polyhydroxyl compounds or polyamino compounds, the polyhydroxyl compound is preferably, but not limited to, water, ethylene glycol, 1, 2-propylene glycol, 1, 3-propylene glycol, diethylene glycol, trimethylolpropane, glycerol, bisphenol A, bisphenol S or a mixture thereof, and the polyamino compound is preferably, but not limited to, ethylene diamine, propylene diamine, butylene diamine, hexamethylene diamine, diethylene triamine, toluene diamine or a mixture thereof.
The polyether carbonate polyol may also be used in the present invention. The polyether carbonate polyol can be prepared by the addition reaction of carbon dioxide and alkylene oxide with a double metal cyanide catalyst in the presence of an active hydrogen-containing starter.
Said polyester polyol is prepared by reacting dicarboxylic acid or dicarboxylic anhydride with polyol. The dicarboxylic acid is preferably, but not limited to, an aliphatic carboxylic acid having 2-12 carbon atoms, and the aliphatic carboxylic acid having 2-12 carbon atoms is preferably, but not limited to, succinic acid, malonic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, lauryl acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid, or a mixture thereof. The dicarboxylic anhydride is preferably, but not limited to, phthalic anhydride, tetrachlorophthalic anhydride, maleic anhydride, or a mixture thereof. The polyol that is reacted with dicarboxylic acid or dicarboxylic anhydride is preferably, but not limited to ethylene glycol, diethylene glycol, 1, 2-propylene glycol, 1, 3-propylene glycol, dipropylene glycol, 1, 3-methylpropylene glycol, 1, 4-butylene glycol, 1, 5-pentylene glycol, 1, 6-hexylene glycol, neopentyl glycol, 1, 10-decanediol, glycerol, trimethylolpropane, or a mixture thereof. The polyester polyol also comprises a polyester polyol prepared from lactone. The polyester polyol prepared from lactone is preferably, but not limited to ε-caprolactone. Preferably, the polyester polyol has the molecular weight of 200-3000 and the functionality of 2-6, preferably 2-5, more preferably 2-4.
The polycarbonate diol can be prepared by reacting a diol with a dihydrocarbyl carbonate or a diaryl carbonate or phosgene. The diol is preferably, but not limited to, 1, 2-propylene glycol, 1, 3-propylene glycol, 1, 4-butylene glycol, 1, 5-pentylene glycol, 1, 6-hexylene glycol, diethylene glycol, trioxymethylene diol, or a mixture thereof. The dihydrocarbyl carbonate or the diaryl carbonate is preferably, but not limited to, diphenyl carbonate.
The polymeric polyol may be a polymer-modified polyether polyol, preferably a grafted polyether polyol, a polyether polyol dispersion. The grafted polyether polyol is preferably a grafted polyether polyol based on styrene and/or acrylonitrile; said styrene and/or acrylonitrile can be formed by in- situ polymerization of styrene, acrylonitrile and a mixture of styrene and acrylonitrile; in said mixture of styrene and acrylonitrile, the ratio of styrene to acrylonitrile is 90: 10-10: 90, preferably 70: 30-30: 70. The polymeric polyol of the present invention can also be a bio-based polyol such as castor oil and wood tar. The polymeric polyether polyol dispersion comprises a dispersion phase, such as inorganic filler, polyurea, polyhydrazide and polyurethane containing tertiary amino groups and/or melamine in a bonded form. The amount of the dispersion phase is 1-50 wt%, preferably 1-45 wt%, based on 100 wt%of the weight of the polymeric polyether polyol. Preferably the polymeric polyether polyol has the polymer solid content of 20%-45%, based on 100%of the weight of said polymeric polyether, and the hydroxyl value of 20-50 mg KOH/g.
When used in the present invention, the vegetable oil-based polyol includes a vegetable oil, a vegetable oil polyol or a modified product thereof. The vegetable oil is a compound prepared from an unsaturated fatty acid and glycerol, or is an oil and fat extracted from fruits, seeds and germs of plants, and is preferably, but not limited to, peanut oil, soybean oil, linseed oil, castor oil, rapeseed oil, and palm oil. The vegetable oil polyol is a polyol initiated from one or more vegetable oils. The starter for synthesizing the vegetable oil polyol includes, but is not limited to, soybean oil, palm oil, peanut oil, low erucic acid rapeseed oil, and castor oil. A hydroxyl group can be introduced into the starter of the vegetable oil polyol through the process such as cracking, oxidation, or trans-esterification, and then the corresponding vegetable oil polyol can be prepared by a process for preparing an organic polyol well known to those skilled in the art.
When used in the present invention, unless otherwise specified, the functionality and the hydroxyl value of the organic polyol refer to the average functionality and the average hydroxyl value.
The flame retardant of the present invention comprises a halogen-free phosphorus-containing flame retardant and a halogen-containing flame retardant.
Preferably, the halogen-free phosphorus-containing flame retardant is selected from halogen-free phospho-acid esters, preferably tricresyl phosphate, diethyl ethylphosphonate (DEEP) , triethyl phosphate (TEP) , dimethyl propylphosphonate, dimethyl methylphosphonate (DMPP) , cresyl diphenyl phosphate (CDP) , triphenyl phosphate. The halogen-free phosphorus-containing polyol can also be selected from halogen-free phosphorus-containing polyols, preferably glycol bis (2-chloroethyl) phosphate, tris (polyoxyalkylene) phosphate, tris (polyoxyalkylene) phosphite, tri (dipropylene glycol) phosphite, tris (hydroxymethyl) phosphine oxide, or a combination thereof. The halogen-free phosphorus-containing flame retardant is more preferably triethyl phosphate, trimethyl phosphate, dimethyl methylphosphonate, tris (hydroxymethyl) phosphine oxide or a combination thereof, particularly preferably triethyl phosphate.
Preferably, the halogen-containing flame retardant is selected from tri (2-chloroethyl) phosphate, tri (2-chloropropyl) phosphate (TCPP) , tri (1, 3-dichloropropyl) phosphate, or a combination thereof, preferably tri (2-chloropropyl) phosphate, tri (1, 3-dichloropropyl) phosphate or a combination thereof, more preferably tri (2-chloropropyl) phosphate.
Preferably, the weight ratio of the content of phosphorus in the flame retardant to the content of halogen in the flame retardant is ≥0.8, preferably ≥1.0, further preferably ≥1.2.
Preferably, the flame retardant comprises at least one halogen-free phosphorus-containing flame retardant and at least one halogen-containing flame retardant. The halogen-containing flame retardant is preferably a chlorine-containing flame retardant.
Preferably, the weight ratio of the content of the halogen-free phosphorus-containing flame retardant to the content of the halogen-containing flame retardant is 0.6-33, preferably 0.8-16, more preferably 1.1-10.
Preferably, the content of the halogen-free phosphorus-containing flame retardant is ≥50 wt%, preferably 50-95 wt%, based on the total weight of the flame retardant.
Preferably, the content of the flame retardant is 20-60 wt%, preferably 30-50 wt%, based on the total weight of the polyol composition.
Preferably, the polyol composition also comprises B4) at least one catalyst, preferably a metal catalyst. The catalyst is preferably, but not limited to an amine catalyst, an organometallic catalyst or a mixture thereof. The amine catalyst is preferably, but not limited to triethylamine, tributylamine, triethylenediamine, N-ethylmorpholine, N, N, N', N'-tetramethyl-ethylene diamine, pentamethyldiethylene-triamine, N, N-methylaniline, N, N-dimethylaniline, or a mixture thereof. The metal catalyst comprises an organometallic catalyst. The organometallic catalyst is preferably, but not limited to an organotin-tpye compound, an organocopper-type catalyst, an organobismuth-type catalyst, for example: tin (II) acetate, tin (II) octoate, tin ethylhexanoate, tin laurate, dibutyltin oxide, dibutyltin dichloride, dibutyltin diacetate, dibutyltin maleate, dioctyltin diacetate, bismuth neodecanoate, or a mixture thereof. The amount of the catalyst is 0.001-3 wt%, based on the total weight of the polyol composition.
Optionally, the above-mentioned polyol composition can also contain auxiliaries or additives comprising, but not limited to: filler, internal release agent, flame retardant, smoke suppressant, dye, pigment, antistatic agent, antioxidant, UV stabilizer, diluent, organic acid, inorganic acid, masking agent, organic ligand, defoamer, coupling agent, surface wetting agent, leveling agent, water-removing agent, catalyst, molecular sieve, thixotropic agent, plasticizer, foaming agent, foam stabilizing agent, foam stabilizer, free radical reaction suppressant or a combination thereof, and these component may be optionally contained in the component A) isocyanate and/or the polyol composition of the present invention. These components can also be independently stored as a further component and, when used for preparing a polyurethane composite, are mixed with the component A) isocyanate and/or the polyol composition before the preparation.
In some embodiments of the present invention, the filler is selected from: aluminum hydroxide, bentonite, pulverized fuel ash, wollastonite, perlite powder, hollow microsphere, calcium carbonate, talcum powder, mica powder, porcelain clay, fumed silica, expandable microsphere, diatomite, volcanic ash, barium sulfate, calcium sulfate, glass microsphere, stone powder, wood flour, wood chip, bamboo powder, bamboo chip, rice grain, straw chips, sorghum straw chips, graphite powder, metal powder, thermosetting composite recycled powder, plastic particle or powder, or a combination thereof. Among others, the glass microspheres can be solid or hollow.
Preferably, the flame retardant is a mixture of tri (2-chloropropyl) phosphate and triethyl phosphate, wherein the weight ratio of the content of triethyl phosphate to the content of tri (2-chloropropyl) phosphate is ≥0.8, preferably ≥1.0, more preferably 1.1-10.
In a preferred embodiment of the present invention, in step ii) , the fiber-reinforced material is selected from glass fibers, aramid fibers, carbon fibers, natural fibers, metal fibers or a mixture thereof. Preferably the fiber-reinforced material is the glass fiber. The glass fiber can be used in the form of untwisted roving, untwisted roving fabric, glass fiber mat and glass fiber fabric.
The pultrusion molded polyurethane composite of the present invention not only has the excellent flame retardant property, but also has the improved weather resistance. The weather resistance of the material refers to the durability of the material when exposed to climatic conditions such as sunlight, cold and hot weather, wind and rain, and the like. The method for measuring the weather resistance comprises the aging test, which simulates natural climatic conditions to proceed the measurement.
Through repeated experiments, we have surprisingly found that the polyol composition of the present invention can be used for safely and effectively preparing the polyurethane resin and the polyurethane composite which have good flame retardant property, excellent quality and satisfactory surface condition.
Explanation of the performance parameter tests in examples of the present application:
Functionality, refers to the value determined according to the industry formula: functionality= hydroxyl value*molecular weight/56100; wherein the hydroxyl value can be determined according to ISO14900-2017 and the molecular weight is determined by GPC high performance liquid chromatography (with reference to DIN 55672-1: 2007) ;
Isocyanate index, refers to the value calculated by the following formula:
Isocyanate index=mole number of isocyanate groups (NCO) in A-component/mole number of isocyanate-reactive hydrogens in B-component
NCO content, refers to the content of the NCO groups in the system, and is measured according to ISO14896-2009.
wt%, refers to the percent by weight.
Gel time refers to the time from when the component A and B of the reaction system start mixing until the viscosity reaches a certain value (for example, about 10000 mPa·s) . The gel time of the present invention is tested using a gel tester. In the test, component A and B are mixed evenly, and then placed in the gel tester. The time from pressing the start button until the gel tester stops working is recorded as the gel time. Gel time of this invention is tested by a gel tester GT-STHP-220 from Shanghai Sen Lan Scientific Instrument Co. Ltd..
Examples
The present invention will be further described with reference to the following examples. The following examples are for the purpose of enabling those of ordinary skill in the art to better understand the present invention, which is for illustrative purposes only, and is not intended to limit the scope of the present invention.
Description of raw material and equipment
Flame retardance test of the pultrusion molded polyurethane composite
Method of vertical burning test in the fiber direction, refers to such a test, in which the length direction of a sample strip of the polyurethane composite to be tested is regarded as the fiber direction, and the flame is made parallel to the fiber direction, the sample strip placed in the vertical direction is ignited with a small flame ignition source in a specified test box, and the burning resistance of the sample/sample strip is evaluated by measuring the total burning time according to IEC 60695-11-10: 2013 Test Method B. The shorter the total burning time, indicating the better the burning resistance of the sample strip.
The weather resistance of the material refers to the durability of the material when exposed to climatic conditions such as sunlight, cold and hot weather, wind and rain, and the like. The method for measuring the weather resistance comprises the aging test, which simulates natural climatic conditions to carry out the measurement.
Preparation of polyurethane composite
Taking the production of a 3mm*100mm flat plate as an example, the process of producing a matted glass fiber reinforced polyurethane pultrusion composite is described in detail. Firstly, a glass fiber roving and a glass fiber mat were passed through a preform rack and sequentially into a glue-injection box and a mold. The polyurethane composition was removed from a raw material tank with a metering and mixing tool and injected into the glue-injection box/soakage box. In the glue-injection box/soakage box, the polyurethane composition soaked the glass fiber roving and the glass fiber mat to the full. The fully soaked glass fiber roving and glass fiber mat were sent into the heating mold cavity for curing and shaping. The molded product was pulled out of the mold with a pultrusion machine, and the state at the mold outlet such as the smoke amount and the surface quality of the plate was observed and recorded. The cutting was performed according to the length requirement of the product to obtain the polyurethane composite. The vertical burning performance of the sample was tested and recorded. According to the aforementioned method for preparing the polyurethane composite, Comparative Examples C1-C5 and Examples 1-4 were obtained according to the proportion of various components as shown in Table 1 below and tested, and the results were shown in Table 1. Wherein, P content wt%, refers to the content of phosphorus in the flame retardant based on the total weight of the isocyanate-reactive component (namely the polyol composition of the present invention) ; halogen content wt%, refers to the content of the halogen (in the preferred examples of the present invention, the halogen is selected from chlorine) in the flame retardant based on the total weight of the isocyanate-reactive component (namely the polyol composition of the present invention) . P/halogen weight ratio, refers to the weight ratio of the phosphorus content to the halogen content in the flame retardant based on the total weight of the isocyanate-reactive component (namely the polyol composition of the present invention) .

Claims

A polyol composition for preparing a polyurethane composite, comprising:

B1) based on the total weight of the polyol composition, 30-60 wt%, preferably 35-55 wt%of an organic polyol, preferably a polyether polyol, having the functionality of 2-5, preferably 2-4 and the average weight-average molecular weight of≤900 g/mol, preferably≤800 g/mol, more preferably≤750 g/mol (measured according to DIN55672-1: 2007) ;

B2) based on the total weight of the polyol composition, 0-30 wt%, preferably 5-25 wt%of a polyether polyol, having the functionality of 2-3 and the average weight-average molecular weight of≥1200 g/mol, preferably≥1500 g/mol, more preferably≥2000 g/mol (measured according to DIN55672-1: 2007) ;

B3) based on the total weight of the polyol composition, 20-60 wt%, preferably 25-55 wt%, more preferably 30-50 wt%of a flame retardant comprising at least two flame retardants each independently comprising halogen and/or phosphorus;

wherein, the phosphorus content of the flame retardant is 2.7-10 wt%, preferably 3.5-8.3 wt%, based on the total weight of the polyol composition;

the halogen content of the flame retardant is 0.3-8.4 wt%, preferably 0.5-7 wt%, based on the total weight of the polyol composition;

wherein the polyol composition comprises less than 10 wt%, preferably less than 8wt%, based on the total weight of the polyol composition, of solid filler and/or wherein the polyol composition comprises less than 1.0 wt%, preferably 0.50 wt%or less, more preferably 0.30 wt%or less, based on the total weight of the polyol composition, of foaming agent.
The polyol composition according to claim 1, characterized in that the weight ratio of the content of phosphorus in the flame retardant to the content of halogen in the flame retardant is 0.6-33, preferably 0.8-16, more preferably 1.1-10.
The polyol composition according to claim 1 or 2, characterized in that the flame retardant comprises at least one halogen-free phosphorus-containing flame retardant and at least one halogen-containing flame retardant.
The polyol composition according to claim 3, characterized in that the weight ratio of the content of the halogen-free phosphorus-containing flame retardant to the content of the halogen-containing flame retardant is≥0.8, preferably≥1.0, more preferably 1.1-10.
The polyol composition according to claim 3 or 4, characterized in that the content of the halogen-free phosphorus-containing flame retardant is≥50 wt%, preferably 50-95 wt%, based on the total weight of the flame retardants.
The polyol composition according to claim 1 or 2, characterized in that the flame retardants are tri (2-chloropropyl) phosphate and triethyl phosphate, the weight ratio of the content of triethyl phosphate to the content of tri (2-chloropropyl) phosphate is≥0.8, preferably≥1.0, more preferably 1.1-10.
A polyurethane reaction system, comprising:

Component A, comprising: at least one isocyanate;

Component B, comprising: the polyol composition according to any of claims 1-6,

wherein the polyurethane reaction system comprises less than 10 wt%, preferably less than 8.0 wt%, based on the total weight of the polyol composition, of solid filler and/or wherein the polyurethane reaction system comprises less than 1.0 wt%, preferably 0.50 wt%or less, more preferably 0.30 wt%or less, based on the total weight of the polyol composition, of foaming agent.
The polyurethane reaction system according to claim 7, characterized in that the isocyanate index of the polyurethane reaction system is 1.05-2.5, preferably 1.15-2.0, more preferably 1.2-1.8.
The polyurethane reaction system according to claim 7 or 8, characterized in that the polyurethane reaction system has a gel time at 25℃ of 15-90 minutes, preferably 20-70 minutes, more preferably 25-50 minutes.
A method for preparing a polyurethane resin comprising reacting the polyurethane reaction system according to any one of claims 7 to 9.
A method for preparing a polyurethane composite comprising:

providing the polyurethane reaction system according to any one of claims 7 to 9 and

Component C, at least one fiber-reinforced material;

bringing the polyurethane reaction system into contact with Component C; and

reacting the polyurethane reaction system.
A polyurethane composite obtained by the method for preparing a polyurethane composite according to claim 11.
The polyurethane composite according to claim 12, characterized in that the content of phosphorus in the flame retardant in the polyurethane composite is 0.4-5 wt%, preferably 0.63-3.73 wt%, more preferably 0.7-2.32 wt%, based on the total mass of the polyurethane composite; the content of halogen in the flame retardant in the polyurethane composite is 0.045-4.2 wt%, preferably 0.09-3.15 wt%, more preferably 0.1-1.96 wt%, based on the total mass of the polyurethane composite.
The polyurethane composite according to claim 12 or 13, characterized in that the total burning time for the polyurethane composite vertically burning in the fiber direction is≤150 seconds, preferably≤145 seconds, more preferably≤130 seconds.
A polyurethane product, comprising the polyurethane composite according to any of claims 12 -14, characterized in that the polyurethane product is selected from: cable trays, frames of doors, windows and curtain walls, frames of ladders, tent poles or pipes, anti-glare shields, floors, sucker rods, telegraph poles and cross arms, guardrails, gratings, architectural sectional materials, container sectional materials and plates, bike racks, fishing rods, cable cores, insulator core rods, antenna housings, single-layer or sandwiched continuous plates, sleepers, main spars and auxiliary spars of the turbine fan blade, preferably sleepers or sheets for producing main spars and/or auxiliary spars of the turbine fan blade.