Composite materials formed using polyols polymerized with lewis acids and methods of making same

Abstract

A method includes forming a composite material, the method comprising reacting: an isocyanate component; an isocyanate-reactive component comprising at least one Lewis acid catalyzed polyether polyol, based on the weight of the isocyanate-reactive component, the weight of the at least one Lewis acid catalyzed polyether polyol being less than the weight of the at least one Lewis acid catalyzed polyether polyol; the polyether polyol having 90 weight percent (wt.%) or more of polypropylene oxide, a primary hydroxyl group concentration of at least 30 wt.%, a functionality of at least 2, an OH number in the range of 100 mg KOH / g to 800 mg KOH / g, an average acetal content of at least 0.05 wt.%, and a water content in the range of 0.1 wt.% to 2 wt.%; and wherein a reinforcing material is present in at least one of the isocyanate component, the isocyanate reactive component, or the third component.

Description

TECHNICAL FIELD

[0001] Embodiments relate to polyurethane compositions for making polyurethane composites and reinforced materials having improved mechanical properties. BACKGROUND

[0002] Polyurethane (PU) formulations can be made into reinforced composites for structural parts using a variety of methods including long fiber injection (LFI), reinforced reaction injection molding (RRIM), and the like. For the LFI method, PU resin is simultaneously sprayed or cast with short fiber glass into an open mold. When the mold is covered with LFI-PU material, the mold is closed and compression occurs at elevated temperature, triggering the cure of the polyurethane. An advantage of the LFI-PU fabrication process is the ability to employ discontinuous lengths of reinforcing fiber, which can be concentrated at targeted structural locations. The final composite article can then exhibit good surface quality and low thermal expansion.

[0003] As with most fabrication techniques, reducing the demolding time while maintaining or improving product quality results in increased productivity. To reduce the demolding time, higher loadings of catalyst or polyols containing higher concentrations of reactive primary hydroxyl groups (e.g., EO derivatives) can be used. However, the use of polyurethane catalysts can be too expensive and can increase the volatility and shorten the cure time of the formulation during processing. Polyols containing high concentrations of primary hydroxyl groups can be obtained using EO as the alkoxylating agent, which results in higher hygroscopicity and can result in the accumulation of water in the formulation when exposed to the atmosphere. The increased polarity of the EO-containing polyols can also result in problems with compatibility with non-polar formulation components and the generation of haze and cloudiness. SUMMARY

[0004] In one aspect, embodiments of the present disclosure include a method of forming a composite material, the method comprising reacting: an isocyanate component; an isocyanate-reactive component, the isocyanate-reactive component comprising at least one Lewis acid-catalyzed polyether polyol having 90 weight percent (wt%) or more polypropylene oxide, a primary hydroxyl concentration of at least 30 wt%, a functionality of at least 2, an OH number in the range of 100 mg KOH / g to 800 mg KOH / g, an average acetal content of at least 0.05 wt%, and a water content in the range of 0.1 wt% to 2 wt%, based on the weight of the isocyanate-reactive component; and wherein a reinforcing material is present in at least one of the isocyanate component, the isocyanate-reactive component, or a third component. BRIEF DESCRIPTION OF DRAWINGS

[0005] Figure 1is a plot of compressive strength as a function of displacement measured according to ASTM D1621 for comparative polyols and Lewis acid polymerized polyols. DETAILED DESCRIPTION

[0006] Embodiments relate to two-component polyurethane compositions for composite manufacturing, where the composition includes a specific type of Lewis acid catalyzed polyether polyol produced by polymerization in the presence of a perfluoroalkyl-substituted aryl borane catalyst. The polyurethane composition includes an isocyanate component and an isocyanate-reactive component, which includes at least the Lewis acid catalyzed polyether polyol. The Lewis acid catalyzed polyether polyols disclosed herein can have 90 percent by weight (wt%) or more polypropylene oxide, a primary hydroxyl concentration of at least 30 wt%, a functionality of at least 2, an OH number in the range of 100 mg KOH / g to 800 mg KOH / g, and an average acetal content of at least 0.05 wt%. Methods also include forming a composite, which includes combining the components using a suitable process such as LFI in the presence of a reinforcing material.

[0007] The use of Lewis acid polymerization catalysts (e.g., perfluoroalkyl-substituted aryl borane catalysts) to produce polyether polyols can improve the reactivity of the polyol with the isocyanate component by increasing the percentage of primary hydroxyl groups, particularly for polyether polyols based on (or containing) polypropylene oxide. The increased concentration of primary hydroxyl groups is associated with faster cure times and improved appearance of the final product. Comparative formulations that include a concentration of polyethylene oxide to increase the percentage of primary OH end groups produce some reduction in the demold time during manufacturing. However, the presence of polyethylene oxide also results in reduced compatibility with non-polar polymer phases and layers, such as PVC skin layers, produces open cell structures that are prone to discoloration by oxidative gases, and scorch associated with high reactivity. On the other hand, polypropylene oxide based polyether polyols show good compatibility with non-polar phases, but production of the polyether polyols by standard KOH alkoxylation catalysis from monomers with carbon number greater than 2 (i.e., propylene oxide, butylene oxide) produces products with >95% secondary OH groups.

[0008] The PU compositions and composites disclosed herein include polyether polyols produced by Lewis acid catalyzed polymerization, which increases the percentage of primary hydroxyl groups and associated performance properties (e.g., reactivity, demold time, etc.). The PU compositions and composites disclosed herein exhibit fast demold and cycle times, while unexpectedly exhibiting enhanced mechanical strength relative to comparative reactive polyols (e.g., PO based polyols). In some cases, PU formulations containing Lewis acid catalyzed polyether polyols can enable the formation of composites with good mechanical properties and good adhesion to PVC skin layers. According to ASTM D7487-18, as measured by FOAMAT™ The PU compositions disclosed herein can be fast curing with long operation times as determined by the Foam Qualification System (Foamat Messtechnik GmbH, Karlsruhe, DE).

[0009] The PU compositions disclosed herein generally include the product obtained by combining a isocyanate component (“A-side”) and an isocyanate-reactive component (“B-side”). During application, the isocyanate and isocyanate-reactive components are mixed, the curing reaction is initiated, and a PU composition or composite material is formed. During formation of the PU composite material, the isocyanate component and the isocyanate-reactive component can be combined in the presence of a reinforcing material (e.g., carbon fiber, fiberglass). In some cases, the reinforcing material can be combined with at least one of the isocyanate or isocyanate-reactive components prior to PU formation, or can be present as a third component that is combined after the mixture of the isocyanate and isocyanate-reactive components.

[0010] The isocyanate component can contain one or more isocyanate compounds, such as polymeric isocyanates, aromatic isocyanates, or carbodiimide-modified isocyanates. The isocyanate compounds can be monomeric, oligomeric, prepolymers, and the like. The isocyanate component can include, for example, one or more isocyanate and / or polyisocyanate compounds. The isocyanate component can include isocyanate compounds having a nominal functionality of 1.5 or greater, or > 2.0 or greater.

[0011] The isocyanate component can include isocyanate compounds having a number average molecular weight of 150 g / mol to 750 g / mol. In some cases, the number average molecular weight of the isocyanate compounds can be a low value of 150 g / mol, 200 g / mol, 250 g / mol, or 300 g / mol to a high value of 350 g / mol, 400 g / mol, 450 g / mol, 500 g / mol, or 750 g / mol. The number average molecular weight values reported herein are determined by end group analysis, gel permeation chromatography, and other methods known in the art. The isocyanate compounds can be monomeric and / or polymeric, as known in the art.

[0012] The isocyanate component can include one or more of aliphatic polyisocyanates, cycloaliphatic polyisocyanates, araliphatic polyisocyanates, aromatic polyisocyanates, and the like. Examples of isocyanates include, but are not limited to, polymethylene polyphenyl isocyanate; toluene 2,4- / 2,6-diisocyanate (TDI); methylene diphenyl diisocyanate (MDI, including its isomers); polymeric and prepolymeric MDI; triisocyanatononane (TIN); naphthyl diisocyanate (NDI); 4,4'-diisocyanate dicyclohexyl-methane; 3-isocyanatomethyl-3,3,5-trimethylcyclohexyl isocyanate (isophorone diisocyanate, IPDI); tetramethylene diisocyanate; hexamethylene diisocyanate (HDI); 2-methyl-pentamethylene diisocyanate; 2,2,4-trimethylhexamethylene diisocyanate (THDI); dodecamethylene diisocyanate; 1,4-diisocyanatocyclohexane; 4,4'-diisocyanato-3,3'-dimethyl-dicyclohexylmethane; 4,4'-diisocyanato-2,2-dicyclohexylpropane; 3-isocyanatomethyl-1-methyl-1-isocyanatocyclohexane (MCI); 1,3-diisooctylcarbonyl-4-methylcyclohexane; 1,3-diisocyanato-2-methylcyclohexane; and combinations thereof, and the like. In addition to the isocyanates mentioned above, partially modified polyisocyanates can be utilized, including uretdione, isocyanurate, carbodiimide, uretonimine, allophanate, or biuret structures, and combinations thereof, and the like. Examples of commercial isocyanates include, but are not limited to, polyisocyanates available from Dow Chemical Company under the trade names VORANATE ™ , VORATRON ™ , PAPI ™ , VORAFORCE ™ , and ISONATE ™ .

[0013] The isocyanate component can include isocyanate prepolymers resulting from the reaction of an isocyanate-reactive compound with a stoichiometric excess of a polyisocyanate compound or polymeric isocyanate compound under conditions that do not result in gelling or curing, which isocyanate prepolymers can have a higher average isocyanate equivalent weight of > 140 g / eq. The formation of isocyanate prepolymers is known in the art and can include reacting (1) at least one isocyanate compound and (2) at least one polyol compound. The isocyanate prepolymers can be described by NCO%, which is defined as the weight percent of residual isocyanate groups remaining after the reaction of an isocyanate compound with a stoichiometrically deficient isocyanate-reactive compound. The isocyanate component disclosed herein can include one or more isocyanate compounds having an NCO content of 20 wt% or more, such as in the range of 20 wt% to 50 wt% or 20 wt% to 48 wt%.

[0014] The isocyanate component includes at least one isocyanate group-containing material, such as a polyisocyanate and / or an isocyanate-terminated prepolymer. For example, the isocyanate component includes at least one aromatic polyisocyanate, such as methylene diphenyl diisocyanate (MDI) and / or toluene diisocyanate (TDI). To form the polyurethane polymer, the isocyanate and isocyanate-reactive components can be mixed prior to use and applied to the substrate, and / or applied separately to the substrate and allowed to mix on the substrate. The isocyanate component can include at least 50 wt% (at least 60 wt%, at least 70 wt%, at least 80 wt%, at least 90 wt%, at least 95 wt%, at least 98 wt%, etc.) of one or more polyisocyanates, based on the total weight of the isocyanate component.

[0015] The PU compositions disclosed herein can include an isocyanate component in the range of 15 wt% to 80 wt%, 20 wt% to 80 wt%, or 20 wt% to 70 wt%.

[0016] The PU compositions can include an isocyanate-reactive component containing at least one polyether polyol prepared using a Lewis acid catalyst. Lewis acid catalyzed polyether polyols can be prepared by polyaddition (alkoxylation) of an alkylene oxide onto an initiator (i.e., a polyhydroxy-functional starter compound) in the presence of a catalyst known in the art, which can shape the ratio of primary and secondary hydroxyl groups in the resulting polymer or oligomer. For example, alkoxylation using a Lewis acid catalyst results in an increased amount of primary hydroxyl groups, while the use of a basic catalyst produces secondary hydroxyl groups as the primary product. Representative methodologies for producing polyether polyols using Lewis acid catalysts are discussed, for example, in WO2019055725 and WO2019055727.

[0017] The initiator comprises one or more compounds having a low molecular weight and a numerical hydroxyl functionality of at least 2. The initiator is any organic compound that will be alkoxylated in the polymerization reaction. The initiator can contain up to 10 hydroxyl groups. For example, the initiator can be a diol or triol. Mixtures of initiators can be used. The hydroxyl equivalent weight of the initiator will be less than the hydroxyl equivalent weight of the polyether product, for example, can have a hydroxyl equivalent weight of less than 500 g / mol equivalent, less than 300 g / mol equivalent, greater than 20 g / mol equivalent, 20 g / mol to 300 g / mol equivalent, 20 g / mol to 200 g / mol equivalent, 30 g / mol to 150 g / mol equivalent, etc. Exemplary initiator compounds such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,8-octanediol, cyclohexanedimethanol, bisphenol A, glycerol, trimethylolpropane, trimethylolethane, pentaerythritol, sugars and sugar alcohols such as sorbitol and sucrose, and / or alkoxylates, any of these having a weight average molecular weight less than the weight average molecular weight of the polymerization product.

[0018] The Lewis acid catalyzed polyether polyols can have a functionality of at least 2 or more, such as in the range of 2 to 6 or 2 to 4. The Lewis acid catalyzed polyether polyols can have an average primary hydroxyl content of at least 25% or more or 30% or more, such as in the range of 25% to 85%, or 30% to 80%. The Lewis acid catalyzed polyols disclosed herein can have a low VOC content (e.g., propionaldehyde and acetal), and a selectivity of up to 65% for PO derived primary hydroxyl terminated polyol chains. The Lewis acid catalyzed polyether polyols can have an average acetal content of at least 0.05 wt%, or at least 0.1 wt%.

[0019] The Lewis acid catalyst can be an aryl borane catalyst having at least one fluoro / chloro or fluoroalkyl substituted phenyl group, which can allow for improved reaction yields. The polymerization catalyst can be fed into the reactor in an amount greater than 0 and less than or equal to 0.005 (e.g., greater than 0.0001, less than or equal to 0.003, less than or equal to 0.001, etc.) mole equivalents per mole of initiator. The Lewis acid catalyst can be active at lower temperature ranges (e.g., 60°C - 110°C).

[0020] The Lewis acid polymerization catalyst has the general formula M(R 1 )1(R 2 )1(R 3 )1(R 4 ) 0或1 where M is boron, aluminum, indium, bismuth, or erbium, R 1 comprises (e.g., consists of) a first fluoro / chloro or fluoroalkyl substituted phenyl group, R 2comprises, for example, a second fluoro / chloro or fluoroalkyl substituted phenyl group, R 3 comprises, for example, a third fluoro / chloro or fluoroalkyl substituted phenyl group or a first functional group or a functional polymer group, and optionally R 4 is a second functional group or a functional polymer group. As used herein, a fluoro / chloro or fluoroalkyl substituted phenyl group refers to a phenyl group having a fluoro / chloro substituted phenyl group or a fluoroalkyl substituted phenyl group as described below. A fluoroalkyl substituted phenyl group refers to a phenyl group comprising at least one hydrogen atom replaced by a fluoroalkyl group. A fluoro substituted phenyl group refers to a phenyl group comprising at least one hydrogen atom replaced by a fluorine atom. A chloro substituted phenyl group refers to a phenyl group comprising at least one hydrogen atom replaced by a chlorine atom. A fluoro / chloro substituted phenyl group refers to a phenyl group comprising at least one hydrogen atom replaced by a fluorine or chlorine atom, and the phenyl group can comprise a combination of fluorine atom and chlorine atom substituents. 1 , R 2 , and R 3 may each independently comprise or may each independently consist essentially of a fluoro / chloro or fluoroalkyl substituted phenyl group. M in the general formula can exist as a metal salt ion or as an integral bonded portion of the formula.

[0021] With respect to R 3 and optional R 4 , the functional group or functional polymer group can be a Lewis base that forms a complex with a Lewis acid catalyst (e.g., a boron-based Lewis acid catalyst) and / or a molecule or moiety that contains at least one electron pair available to form a dative bond with a Lewis acid (e.g., a cyclic ether such as tetrahydrofuran). The Lewis base can be a polymeric Lewis base. The functional group or functional polymer group refers to a molecule that contains at least one of the following: water, an alcohol, an alkoxy group (examples include linear or branched ethers and cyclic ethers), a ketone, an ester, an organosiloxane, an amine, a phosphine, an oxime, and substituted analogs thereof. Each of the alcohol, linear or branched ether, cyclic ether, ketone, ester, alkoxy group, organosiloxane, and oxime can comprise 2-20 carbon atoms, 2-12 carbon atoms, 2-8 carbon atoms, and / or 3-6 carbon atoms. For example, the functional group or functional polymer group can have the formula (OYH) n where O is oxygen, H is hydrogen, Y is H or a hydrocarbyl group, and n is an integer (e.g., an integer from 1 to 100). However, other known functional polymer groups that can be combined with a Lewis acid catalyst (such as a boron-based Lewis acid catalyst) can be used. Exemplary cyclic ethers include tetrahydrofuran and tetrahydropyran.

[0022] In some cases, the Lewis acid polymerization catalyst can be a Lewis acid polymerization catalyst as shown in Structure I.

[0023]

[0024] Lewis acid-catalyzed polyether polyols may have OH values ​​in the range of 100 mg KOH / g to 900 mg KOH / g, 100 mg KOH / g to 800 mg KOH / g, or 100 mg KOH / g to 750 mg KOH / g. Lewis acid-catalyzed polyether polyols may have number-average molecular weights of 400 Da or greater, 450 Da or greater, or 500 Da or greater (such as in the range of 400 Da to 2000 Da, or 400 Da to 1500 Da).

[0025] Lewis acid-catalyzed polyether polyols may have a polypropylene oxide content of 80% by weight or higher, or 90% by weight or higher. In some cases, Lewis acid-catalyzed polyether polyols may include polypropylene oxide homopolymers (including polypropylene oxide homopolymers polymerized in the presence of polyhydroxy initiator compounds).

[0026] Lewis acid-catalyzed polyether polyols may be present in the isocyanate reactive component at a weight percentage (wt%) of at least 50 wt% or at least 60 wt% (such as in the range of 40 wt% to 95 wt%, 45 wt% to 95 wt%, or 50 wt% to 90 wt%).

[0027] The method of the present invention may include a long fiber injection molding process for preparing combustion-modified fiber-reinforced polyurethane composites. Long fiber injection (LFI) is a well-known technology in the automotive market for the rapid curing of two-component polyurethanes. The combustion-modified fiber-reinforced polyurethane composite of the present invention can be prepared by performing a long fiber injection molding process, providing a curable polyurethane resin component comprising a reactive polyurethane component, a polyol and an isocyanate, and an isocyanate reactive bromide compound, along with metal hydrate particulate fillers and fibers, and optionally with a phosphorus-based compound, to a suitable mixing head, and expelling the wetted fibers onto a mold. This is done according to ASTM D7487-18, as per FOAMAT. ™ The PU composition disclosed herein has been determined by the Foam Detection System (Foamat Measurement Technologies GmbH, Karlsruhe, Germany) to have rapid curing over long working times. According to ASTM D3574-17 Test A, the density of the PU composition is less than 0.850 g / mL, or in the range of 0.3 g / mL to 0.85 g / mL, or 0.3 g / mL to 0.85 g / mL.

[0028] The polyurethane foam composition can include one or more blowing agents, including water and aqueous fluids; chemical blowing agents, such as hydrocarbons, acids, volatile organics, and the like; and physical blowing agents, including gases, such as nitrogen, air, carbon dioxide, and the like. The blowing agent can be added to the foam-forming composition during mixing in a weight percentage (wt%) ranging from 0.1 wt% to 15 wt% or 1 wt% to 10 wt%. The blowing agent can be added to the isocyanate component and / or the isocyanate-reactive component in an amount sufficient to provide a mixture having the corresponding weight percentages described above. In some cases, the blowing agent can be water and added in a weight percentage ranging from 0.1 wt% to 2 wt% of the composition, based on the weight of the foam-forming composition.

[0029] The isocyanate component and / or the isocyanate-reactive component can have one or more functional additives, as can be used in the particular manufacturing method used or to impart desired properties to the resulting foam. These include, for example, catalysts, chain extenders, odor modifiers, fillers, colorants, flame retardants, pigments, antistatic agents, reinforcing fibers, antioxidants, preservatives, acid scavengers, and the like.

[0030] The polyurethane composition and composite structural parts, particularly for larger vehicles, such as buses. The polyurethane system for LFI composite parts includes a two-component polyurethane formulation that is mixed and injected together into a PVC skin deep draw metal mold during LFI to manufacture the final article. The PU composition can be used to prepare molded composite parts by processes including mixing or injecting the PU composition into a reinforcing material (e.g., by LFI, reinforced reaction injection molding (RRIM), structural reaction injection molding (SRIM), resin transfer molding (RTM), vacuum assisted resin transfer molding (VARTM), and other reactive processing techniques). The reactive processing techniques can include the creation of a composite material in a single step, such as polymer material formation and reinforcement occurring in the same step or cycle. The composition and methods have been discussed with respect to polyurethane composites produced by LFI, however, it is contemplated that the polyurethane composites can be produced by any suitable method without departing from the scope of the present disclosure.

[0031] Suitable reinforcing materials include any one or more of glass fibers, electronic grade glass fibers (e-glass fiber), carbon nanotubes, carbon fibers, polyester fibers, natural fibers, glass fibers, aramid fibers, nylon fibers, mineral fibers, basalt fibers, boron fibers, silicon carbide fibers, asbestos fibers, whiskers, hard particles, metal fibers, and the like. The reinforcing material can include fibers having an aspect ratio (length / diameter) ratio ranging from 600 to 1000. In some cases, the reinforcing material includes fibers (e.g., carbon or glass) having a filament diameter ranging from 15 pm to 25 pm.

[0032] Fiber reinforced polymer composites and methods and systems for making fiber reinforced polymer composites. Embodiments of the invention also include architectural structures comprising the fiber reinforced composites of the invention, such as doors, door skins, structural panels for walls and doors (e.g., garage door panels), door frame components, door and window components (e.g., claddings for window components, window and door frames, plant-ons for doors), shingles, shutters, siding, and other architectural structures comprising the fiber reinforced polymer composites.

[0033] While formulation components and properties have been disclosed individually, it is contemplated that any of the above concentration ranges and nested subranges therein can be utilized to include, exclude, or combine component elements (e.g., compounds in isocyanate or isocyanate-reactive components) in any manner or subcombination. Further, the formulation properties can similarly be achieved by various combinations of the components within the ranges described.

[0034] All parts and percentages are by weight unless otherwise indicated. All molecular weight values are based on number average molecular weight unless otherwise indicated.

[0035] Examples

[0036] The following examples are provided to illustrate embodiments of the invention and are not intended to limit the scope of the invention. Table 1 provides the materials used in the following examples.

[0037]

[0038] Example 1 : Properties of polyurethane compositions

[0039] In this example, samples containing polyurethane compositions were prepared by varying the polyol component of the formulation, combining with isocyanate in the specified ratio, and determining the polyurethane reactivity. The polyurethane was prepared as a 112 g sample. The components were equilibrated to 25 °C and combined using a Heidolph mixer at 3000 rpm. After 10 seconds, the cream time (CT) was determined when the PU started to swell. The gel time (GT) was then measured by repeatedly dipping a rod into the foam, and the time for a wire to be formed was determined as the gel time. The tack free time (TFT) was the time for the surface of the resulting polymer to be free of tackiness. The free rise density (FRD) of the sample was measured after waiting 24 h. The foam was cut at the center (core) in a size of 5 cm x 5 cm x 2.5 cm

[0040] The inventive sample II includes a Lewis acid catalyzed polyol according to the present disclosure, which is a PO based polyol containing about 60 to 65% primary OH content. Comparative polyol 1 in CI is a PO based polyol having similar properties to the Lewis acid catalyzed polyol, but prepared by standard KOH alkoxylation catalysis resulting in >95% secondary OH groups. Comparative polyol 2 in C2 is an EO based polyol having similar OH value and functionality to the Lewis acid catalyzed polyol with 100% primary OH content. Sample formulations and results are provided in Table 2.

[0041]

[0042] In Table 2, the isocyanate index corresponds to 100 (a / b), where a = 72 parts of isocyanate groups in equivalents in the isocyanate component, and b = 40 parts of isocyanate reactive groups in equivalents in the formulated polyol component.

[0043] The polyurethane reactivity in Table 2 shows that C2 containing an EO based polyol has the fastest reactivity in terms of rise time and tack free time, while CI is the slowest. II has similar reactivity to C2.

[0044] Example 2: Compression stress testing of polyurethane compositions

[0045] In the next example, polyurethane samples prepared substantially as described in Example 1 were tested to quantify compressive strength and modulus. Compression stress testing was performed according to ASTM D1621 at 1 mm / minute. The point of deformation was calculated from the stress at 10%. Foam samples were prepared, aged for 24 hours, and sized to 50 mm x 50 mm x 25 mm, with a density of 160 kg / m3. 3 .

[0046] As Figure 1 shown, II formulated with the Lewis acid catalyzed polyol exhibits similar compressive strength and modulus to C2 containing polyol 2 (EO based polyol), while the performance associated with CI containing polyol 1 (PO based, primarily secondary OH) is lower.

[0047] Example 3: Polyol formulation compatibility and storage stability

[0048] In this example, isocyanate-reactive (B-side) formulations containing the sample polyols were prepared and the storage stability was determined. The samples were prepared as shown in Table 2, allowed to sit and observed for signs of separation every 24 hours. The samples prepared with Lewis acid catalyzed polyols or with Comparative Polyol 1 did not exhibit separation over the investigation period. On the other hand, Comparative Polyol 2, an EO-based polyol, was incompatible and the corresponding formulated polyol showed phase separation upon storage, forming a layer corresponding to about 15% of the total polyol formulation on top.

[0049] Example 4: Properties of polyurethane compositions containing fillers

[0050] The samples were prepared essentially as described in Example 1. The filler was dried at 80°C for 24 hours before being loaded into the formulated polyol component.

[0051] Reactivity profiles of the reaction mixture were prepared at 145 g of sample and analyzed using the FOAMAT Foam Identification System. Plaques were prepared for thermal and mechanical properties at an application density of 600 g / l using a horizontal laboratory mold of 200 mm x 200 mm x 3 mm. The flexural properties were measured using a full-thickness sample and using the standard UNI EN ISO 178 at a speed of 10 mm / min.

[0052] Thermal analysis was performed using a UNIVERSAL V TA Q800-DMA instrument to determine the glass transition temperature (Tg). The test method used: Double Cantilever Beam, 1 Hz, heating rate 3°C / min; sample size 60 mm x 12 mm x 4 mm; initial temperature 45°C; final temperature 240°C.

[0053] Samples were manufactured using a flat mold sized at 300 mm x 300 mm x 12 mm, with water heated to a maximum of 90°C. Although the systems tested are used for composite products produced by the LFI process, the samples produced did not contain glass fibers to evaluate only the behavior of the PU foam. Acmos 37-7009 was used as external release agent. The reaction components were allowed to equilibrate at 25°C before reaction. The liquid weight was 650 g. The combined reaction temperature was 50°C. The top of the mold was kept at 45°C and the bottom of the mold was kept at 35°C. The sample demolding time was 18 minutes. The estimated sample volume was 1.11 L. The average sample weight was 570 g and the average density of the sample was 515 g / L ± 5 g / L.

[0054] The formulations and results are shown in Table 3.

[0055]

[0056] As shown in Table 3, I2 is much more reactive than C3, and a surprising improvement in intensity and module performance is obtained with I2 compared to C3.

[0057] While the foregoing is directed to embodiments of the present application, other and further embodiments can be devised without departing from the basic scope of the application, and the scope of the application is determined by the claims that follow.

Claims

1. A method of forming a composite material, the method comprising reacting: an isocyanate component; an isocyanate-reactive component, the isocyanate-reactive component comprising at least one Lewis acid-catalyzed polyether polyol having 90 weight percent (wt%) or more polypropylene oxide, a primary hydroxyl concentration of at least 30 wt%, a functionality of at least 2, an OH number in the range of 100 mg KOH / g to 800 mg KOH / g, an average acetal content of at least 0.05 wt%, and a water content in the range of 0.1 wt% to 2 wt%, based on the weight of the isocyanate-reactive component; and wherein a reinforcing material is present in at least one of the isocyanate component, the isocyanate-reactive component, or a third component.

2. The method of claim 1, wherein the isocyanate-reactive component comprises at least 50 wt% of the polyether polyol.

3. The method of claim 1, wherein the polyether polyol is a polypropylene oxide polyol.

4. The method of claim 1, wherein the composite material has a density of less than 0.85 g / mL.

5. The method of claim 1, wherein the polyether polyol has a weight average molecular weight of 200 Da to 1,000 Da and a functionality of 2 to 4.

6. The method of claim 1, wherein the Lewis acid catalyst used to produce the polyether polyol has the general formula M(R 1 )1(R 2 )1(R 3 )1(R 4 ) 0或1 where M is boron, aluminum, indium, bismuth, or erbium, R 1 , R 2 , R 3 , and R 4 are each independent, R 1 comprises a first fluoro / chloro or fluoroalkyl substituted phenyl group, R 2 comprises a second fluoro / chloro or fluoroalkyl substituted phenyl group, R 3 comprises a third fluoro / chloro or fluoroalkyl substituted phenyl group or a first functional group or functional polymeric group, and optional R 4 is a second functional group or functional polymeric group.

7. The composition of claim 1, wherein the Lewis acid catalyst forms a dative bond with tetrahydrofuran.

8. The method of claim 1, wherein the isocyanate component is present in a weight percent (wt%) in the range of 56 wt% to 86 wt%.

9. The method of claim 1, wherein the composite material is produced by long fiber injection (LFI).

10. An article produced by the method of claim 1.

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