Controllable stretching of flexible oligomeric diols and methods thereof

Abstract

To provide an extended oligomeric diol material while maintaining flexibility and low cost. The present invention provides an extended diol composition comprising a first component comprising a diol oligomer and a second component comprising a bisdimethylaminosilane species, wherein the first component is in molar excess relative to the second component, and the diol oligomer has a number average molecular weight Mn of about 500 g / mol to about 5,000 g / mol. The diol oligomer can be terminated with α,ω-hydroxyl groups or can further comprise an R group that is a polyether, such as perfluoropolyether, polyoxymethylene, polyethylene glycol, polytetramethylene glycol, or poly(propanediol), or a polyester, such as poly(caprolactone), poly(lactic acid), or poly(glycolic acid). The bisdimethylaminosilane species can comprise an R group that can include CH, vinyl, and phenyl. 1 and R 2 may include:

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to U.S. Provisional Patent Application No. 63 / 681,628, filed August 9, 2024, which is incorporated herein by reference in its entirety.

[0002] Technical Field The teachings of the present application relate generally to the fabrication of flexible oligomeric diol compositions, and specifically to the control and extension of such compositions. [Background technology]

[0003] Many commercially available oligomeric diols are produced in the 500-5,000 dalton range. Stretching these oligomeric diols to higher molecular weight diols is desirable to produce more flexible materials with lower crosslink densities. Flexible oligomeric diol compositions can be used in a variety of materials or material compositions in the aerospace industry, for example, for coatings, adhesives, sealants, and elastomers. However, existing materials can be expensive. While precursors are available and relatively inexpensive, some precursors may be limited by the maximum molecular weight available.

[0004] Due to limitations in the available molecular weight of many commercially available oligomeric diols, such materials can be prohibitively expensive and difficult to synthesize directly. Higher molecular weight species of these materials may offer formulators greater options in producing coatings, adhesives, elastomers, and sealants due to the lower modulus materials that can be achieved through the reduced crosslink density afforded by longer diol precursors.

[0005] Therefore, there is a need for a method to achieve a larger molecular weight range with these precursors while maintaining diol end group functionality and limiting modifications to backbone properties, thereby providing stretched materials while maintaining flexibility and low cost. Summary of the Invention

[0006] The following presents a simplified summary in order to provide a basic understanding of some aspects of one or more embodiments of the present teachings. This summary is not an extensive overview, and it is not intended to identify key or critical elements of the present teachings or to delineate the scope of the disclosure. Rather, the primary purpose of the summary is merely to present one or more concepts in a simplified form as a prelude to the more detailed description that is presented later.

[0007] A stretched diol composition is disclosed. The stretched diol composition includes a first component that can include a diol oligomer. The stretched diol composition also includes a second component that can include a bisdimethylaminosilane species, where the first component is in molar excess relative to the second component, and the diol oligomer has a number average molecular weight Mn of about 500 g / mol to about 5,000 g / mol. Embodiments include those in which the diol oligomer is terminated with α,ω-hydroxyl groups. The diol oligomer can further include an R group that is a polyether or polyester. The polyether can include a perfluoropolyether, where the polyether is selected from the group that can include polyoxymethylene, polyethylene glycol, polytetramethylene glycol, poly(propanediol), and perfluoropolyether, and the polyester is selected from the group that can include poly(caprolactone), poly(lactic acid), and poly(glycolic acid). The bisdimethylaminosilane species are both the same and have R selected from the group which may include CH, vinyl, and phenyl. 1 and R 2 The bisdimethylaminosilane species may comprise R groups that are different from each other and selected from the group that may include CH, vinyl, and phenyl. 1 and R 2The stretched diol composition may comprise a terminally functionalized (telechelic) HO-PEG-PFPE-PEG-OH structure, where PEG is defined as poly(ethylene glycol) and PFPE is defined as perfluoropolyether. The bisdimethylaminosilane species may comprise a disilane compound. The bisdimethylaminosilane species may comprise 1,2-bis(dimethylamine)tetramethyldisilane. The molar ratio of the second component to the first component is from about 0.01:1 to about 0.99:1. The stretched diol composition may comprise a molecular weight distribution having a number average molecular weight Mn of from about 5,000 to about 50,000 g / mol.

[0008] Another extended diol composition is disclosed. The extended diol composition also includes a first component, which may include a diol oligomer. The extended diol composition also includes a second component, which may include a bisdimethylaminosilane species, wherein the first component is in molar excess relative to the second component, the diol oligomer has a number average molecular weight Mn of about 500 g / mol to about 5,000 g / mol, and the bisdimethylaminosilane species has an R selected from CH3, vinyl, and phenyl. 1 and R 2 The stretched diol composition may include an embodiment in which the diol oligomer further includes an R group that is a polyether or polyester. The bisdimethylaminosilane species may include 1,2-bis(dimethylamine)tetramethyldisilane. The molar ratio of the second component to the first component is about 0.01:1 to about 0.99:1. The stretched diol composition may include a molecular weight distribution having a number average molecular weight Mn of about 5,000 to about 50,000 g / mol.

[0009] A method for making an extended diol composition is disclosed. The method includes providing a diol oligomer to a reaction vessel, the diol oligomer having an average molecular weight of about 500 to about 5,000 g / mol. The method also includes heating the diol oligomer at a temperature of about 50° C. to about 110° C. in an inert atmosphere. The method also includes adding a bisdimethylaminosilane compound with stirring. An embodiment of the method for making an extended diol composition can include maintaining a molar excess of the diol oligomer to the bisdimethylaminosilane compound, heating the diol oligomer at a temperature between 90° C. and 100° C. for about 1 hour to about 4 hours, and sparging the reaction vessel with nitrogen gas while adding the bisdimethylaminosilane to remove any residual dimethylamine by-product. The diol oligomer may be selected from polyoxymethylene, polyethylene glycol, polyethylenetetramethylene glycol, and perfluoropolyether, and the bisdimethylaminosilane compound may include 1,2-bis(dimethylamine)tetramethyldisilane.

[0010]

[0010] The above-described features, functions, and advantages can be realized alone in various embodiments or can be combined in other embodiments, further details of which can be found by reference to the following description. DETAILED DESCRIPTION OF THE INVENTION

[0011] Many commercially available oligomeric diols are produced in the 500-5,000 dalton range and can be used in coatings, adhesives, sealants, elastomers, and the like. Stretching diols to higher molecular weights is desirable to produce more flexible materials at lower crosslink densities. This disclosure provides a process for stretching oligomeric diols using small, single O-Si-O bonds as linkages, preserving the flexibility and properties of the primary precursor backbone, as opposed to more bulky stretching strategies, such as urethane coupling with diisocyanates, which can alter backbone properties. This reaction produces a relatively pure reaction product in a single reaction step, allowing target molecular weights to be tailored based on the relative ratios of diol and bisdimethylaminosilane compound. Current oligomeric diols in the desired range for use in coatings, adhesives, sealants, and elastomers are either not commercially available or are expensive. The present disclosure provides alternative compositions that can be stretched at low cost while maintaining compositional flexibility and versatility and control of the molecular weight and structure of the oligomeric diol.

[0012] In known examples, a bisdimethylaminosilane coupling strategy with small molecules such as 1,4 bis-(hydroxydimethylsilyl)benzene can be used to produce poly(silphenylenes), which are high-temperature stable polysiloxanes. However, these compositions do not involve the use of or reaction with oligomeric diols (Mw>500) or non-Si-based compounds.

[0013] In the present disclosure, the siloxane linkages formed during the method herein preserve flexibility in the resulting linear backbone. The method includes fabricating an extended diol oligomer composed of one or more first components selected from diol oligomers having an average Mn of 500 to 5,000 g / mol, the poly-oligomers being terminated with α,ω-hydroxyl groups. A second component selected from bisdimethylaminosilane species is also included, with the first component being in molar excess relative to the second component (the molar ratio of the second component to the first component being <1).

[0014] The present disclosure provides a synthetic strategy for controlled molecular weight growth of oligomeric diols. In this description, molecular weight is referred to as the number-average molecular weight, Mn, which can be defined as the ordinary arithmetic mean or average of the molecular weights of the individual constituents. Mn can be determined by measuring the molecular weights of n molecules, adding them together, and dividing by n. This method provides a means for controlled molecular weight growth (Mn) of oligomeric diols. Using a common diol oligomer as a precursor, bisdimethylaminosilane compounds can be used as chain extenders in a step-growth reaction scheme. In a preferred embodiment, the reaction can be carried out at high temperatures (up to 100°C) without the need for solvents, and releases only dimethylamine gas as a by-product.

[0015] The O-Si-O bond generated as a linkage in this synthesis method preserves the flexibility of the linear backbone compared to alternative extension strategies, such as urethane coupling with diisocyanates. A method for increasing the molecular weight of an oligomeric diol includes providing a first polymer precursor that forms a polymer chain and extending the length of the polymer chain by reacting the polymer chain with a second polymer precursor (bisdimethylaminosilane), where the first polymer precursor is a diol oligomer. This method allows for the extension of oligomeric diols using a short spacer in a single reaction without significantly altering the properties of the oligomeric diol. This method also provides enhanced chemical stability. In an example, if the required molecular weight is in the shorter Mn range, the diol can be provided in excess in the reaction.

[0016] This synthetic strategy requires first obtaining an oligomeric diol. The reaction can be carried out with or without a solvent, although a solvent-free process is preferred if the viscosity of the pure resin is low enough for stirring and homogenization. Also, elevated temperatures, such as from about 50°C to about 110°C, and alternatively from 90°C to about 110°C, are desirable. The bisdimethylamino compound can be introduced slowly over time into an inert atmosphere to avoid excessive evolution of dimethylamine gas and the temperature increase associated with the heat of reaction.

[0017] A general representation of a bisdimethylaminosilane species is shown in formula (I): TIFF2026041662000001.tif31170 [where, by way of example, R1 and R2 can be CH3, vinyl or phenyl, and can be the same or different].

[0018] Alternatively, the following compound, 1,2-bis(dimethylamino)tetramethyldisilane, shown in formula (II), can also be used. TIFF2026041662000002.tif23170

[0019] In the examples, the oligomeric diol in the reaction has the following general structure shown in (III): TIFF2026041662000003.tif10170

[0020] In the above oligomeric diol of Formula III, R can be an oligomer having an Mn of about 500 to about 5,000 daltons. The R species can be a polyether, polyester, or polysiloxane. Specific examples of polyethers can include, but are not limited to, polyoxymethylene, polyethylene glycol, polytetramethylene glycol, and perfluoropolyether. Specific examples of polyesters can include, but are not limited to, polycaprolactone, polylactic acid, and polyglycolic acid. R can also include combinations of the above elements in random or block copolymer configurations. The general reaction shown in Scheme 1 below is representative of the reactions disclosed herein, where R1 can be a polyether, polyester, polysiloxane, or perfluoropolyether, R2 and R3 can be methyl, vinyl, or phenyl, and R2 and R3 can be the same or different: TIFF2026041662000004.tif30170

[0021] A particular form of oligomeric diol precursor has a CF2 group β to the hydroxyl in formula (IV). TIFF2026041662000005.tif15170

[0022] In the example of formula (IV), the structure is unique to R, a perfluoropolyether, with a CF group adjacent to the terminal OH group. The broadest scope of the present teachings is the use of the extended oligomer diol product in Scheme 1. More specific examples of interest can include the use of commercially available terminally functionalized precursors based on the HO-PEG-PFPE-PEG-OH structure, where PEG is defined as poly(ethylene glycol) and PFPE is defined as a perfluoropolyether.

[0023] In an embodiment, the stretched diol composition can include a first component including a diol oligomer of Formulas I to IV and a second component including a bisdimethylaminosilane species, wherein the first component is in molar excess relative to the second component in the stretched diol composition. The diol oligomer has a number-average molecular weight Mn of about 500 g / mol to about 5,000 g / mol. Furthermore, the diol oligomer is terminated with α,ω-hydroxyl groups. The stretched diol composition can include a case where the diol oligomer further includes an R group, which can be a polyether, or a case where the bisdimethylaminosilane species includes different R2 and R3 selected from the group consisting of CH3, vinyl, and phenyl, as in Scheme 1 above. In other embodiments, R2 and R3 can be different. The stretched diol composition can include a case where the diol oligomer includes a terminally functionalized HO-PEG-PFPE-PEG-OH structure, or where the polyether includes a perfluoropolyether. In embodiments, the diol oligomers of Formulas I to IV are selected from the group consisting of polyoxymethylene, polyethylene glycol, polyethylenetetramethylene glycol, and perfluoropolyether, or combinations thereof. Other embodiments include those in which the bisdimethylaminosilane species includes a disilane compound, such as 1,2-bis(dimethylamine)tetramethyldisilane. The molar ratio of the second component to the first component in the final stretched diol composition is from about 0.01:1 to about 0.99:1. In other embodiments, a ratio of from about 0.7 to about 0.9 is applicable. Exemplary stretched diol compositions having the first and second components can have a molecular weight distribution with a number average molecular weight Mn of from about 5,000 to about 50,000 g / mol, or from about 5,000 to about 25,000, or from about 10,000 to about 30,000.

[0024] Diol oligomers with molecular weights ranging from approximately 500 to 5,000 grams per mole can be synthesized according to the present disclosure through the reaction of bisdimethylaminosilane compounds with polyether or polyester precursors. The resulting extended diols exhibit improved thermal stability due to the O-Si-O bonds formed during polymerization. In one example, a terminally functionalized HO-PEG-PFPE-PEG-OH structure is used as the precursor material, which can be prepared by reacting a perfluoropolyether with a polyethylene glycol or polycaprolactone-based diol. In this example, polyethylene glycol (PEG), perfluoropolyether (PFPE), and hydroxide groups (OH) are present. The presence of hydroxide groups provides a structure and material that can be classified as a prepolymer, capable of initiating further polymerization or other reactions via these reactive hydroxide end groups.

[0025] In another example, polyester precursors such as polycaprolactone, polylactic acid, and polyglycolic acid can alternatively be used to produce more flexible backbones. The bisdimethylaminosilane compounds used in the reaction shown in Scheme 1 can also be substituted with various R2 and R3 groups, including methyl (CH3), vinyl (-C=CH), or phenyl (-Ph). In one aspect, R2 and R3 can be the same or different alkyl groups, such as ethyl (C2H5), propyl (-n-C3H7), or butyl (-n-C4H9), where the "n" designation indicates a linear hydrocarbon chain. In another example, these substituents can include a phenyl ring. The bisdimethylaminosilane compound can have a linear chain of repeating units between the dimethylamine groups. In another example, R1 and R2 can be methyl (CH3) or vinyl (-C=CH). Another example includes bisdimethylaminosilanes with a phenyl ring on the silicon atom. In another embodiment, the disilane compound may be tetramethyldisilane or other suitable derivatives of dimethylamine and silylene dihydrate (SiH). The R and R substituents may also contain heteroatoms such as oxygen (-O-) or nitrogen (-Nh-). The selection of R and R substituents affects the reactivity, compatibility, and properties of the bisdimethylaminosilane used as a chain extender for the diol oligomer extension reaction. By selecting an appropriate compound from this class, optimal results can be achieved in terms of molecular weight control during polymerization while maintaining flexibility. In one example, bisdimethylaminosilane can be prepared by reacting dichlorosilane with dimethylamine in an inert solvent. The resulting product is then reacted with a diol oligomer to form an extended polymer material. In another example, mixtures of different R, R, or R substituents are prepared and then reacted with a diol oligomer to form extended polymer materials with different properties, such as thermal stability or chemical resistance.

[0026] The synthesis of diol oligomers can be carried out in the presence of a solvent such as tetrahydrofuran (THF), dichloromethane (DCM), xylene, toluene, chloroform, or dimethylformamide (DMF). The choice of solvent depends on factors such as reactivity, viscosity, and solubility of the product. In some cases, no solvent is used during processing due to the low viscosity of the starting material.

[0027] The temperature range for this reaction can be adjusted from about 50°C to about 110°C depending on the characteristics of the reactants and the desired end group functionality. For example, higher temperatures tend to promote a faster condensation reaction, while lower temperatures may reduce side reactants or decomposition products. Alternatively, temperatures from about 25°C to about 90°C may be applicable. The molar ratio of the bisdimethylaminosilane compound to the diol oligomer is also useful for controlling the molecular weight increase during stretching.

[0028] In one example, the reaction mixture can be heated to about 90° C. to about 100° C. by slowly adding the bisdimethylaminosilane compound over a period of time (e.g., approximately 30 minutes). This allows for gradual consumption by the diol oligomers and maintains control over the molecular weight distribution. The rate can vary, for example, from about 1 minute to about 120 minutes, or from about 30 minutes to about 60 minutes, depending on reactant concentration, temperature, or desired product properties.

[0029] The resulting stretched diol may be further functionalized with additives, such as flame retardants, to enhance its performance in various applications, such as coatings, adhesives, sealants, and elastomers. These materials inherently exhibit improved thermal stability due to the presence of O-Si-O bonds formed during polymerization. In embodiments, additives can be blended or mixed with the stretched diol after the reaction or incorporated via an additional reaction during the stretching reaction. Additional additives can include pigments, antioxidants, and UV stabilizers. Examples include carbon black. Note that the incorporation of fillers may be most applicable to incorporating the compositions of the present disclosure into the final resin or sealant composition.

[0030] The solvent used in this reaction is optional and can be selected from a variety of solvents that facilitate efficient mixing of the reactants without interfering with the condensation reaction between the diol oligomer and the bisdimethylaminosilane compound. Suitable examples include, but are not limited to, tetrahydrofuran, dichloromethane, dimethylformamide, toluene, xylene, cyclohexanone, and methyl isobutyl ketone (MIBK). In one embodiment, the solvent can be a mixture of two or more solvents selected from this list to achieve optimal solubility characteristics for specific reactants.

[0031] In another example, if the diol oligomer is of a viscosity that facilitates mixing with the bisdimethylaminosilane compound without further assistance or effort, no solvent may be used at all, which may simplify product purification and reduce waste generation during processing.

[0032] In some embodiments of the present disclosure, it may be desirable to dissolve the mixture of diol oligomer and bisdimethylaminosilane compound in a suitable solvent before heating or during stretching. This can facilitate efficient mixing, heat transfer, and reaction rate while minimizing potential side reactants or impurities resulting from undissolved reactants. Suitable solvents for this purpose include tetrahydrofuran (THF), dichloromethane (DCM), and dimethylformamide (DMF). For example, a 1:2 ratio of THF to diol oligomer can be used in combination with a bisdimethylaminosilane compound concentration ranging from 0.5% to 10%. In another embodiment, DCM can be used for the dissolution process at temperatures between -20°C and room temperature (RT). In certain embodiments, during stretching reactions using perfluoropolyethers as R groups, THF can be added gradually over several hours while maintaining constant stirring conditions. This can help minimize the potential for degradation or side reaction products associated with high-temperature processing of these sensitive materials. In some cases where a solvent is not useful or desirable, insoluble reactants can still achieve efficient mixing and heat transfer through mechanical agitation alone. This can be particularly useful when working with highly viscous diol oligomers or bisdimethylaminosilane compounds, where minimal solvent addition is required for optimal reaction conditions. In some examples where specific functional groups are incorporated into the diol oligomer, solvents such as dimethoxybenzene (DMB) or 1-methyl-2-pyrrolidinone can be used as a medium for efficient dissolution. These solvents can help maintain the concentration of reactants and facilitate the formation of desired chemical bonds.

[0033] The process for providing the diol oligomers involves multiple steps that can be tailored to the particular embodiment and application. In one example, the starting material can include polyethylene glycol (PEG) or other types of polyethers having a molecular weight ranging from approximately 500 to about 5,000 g / mol. PEG can be used in a precursor molecular weight range of about 200 to about 2,000,000. Further examples can include poly(THF) or poly(tetramethylene glycol). These materials can be used in the range of 500 to about 3,000, or about 500 to about 10,000, or up to about 20,000. The PEG is then subjected to an esterification reaction using a suitable catalyst, such as dibutyltin dilaurate and diisophthalic acid, in the presence of tetrahydrofuran (THF) or other solvent at a temperature of 50° C. to 100° C. for several hours, resulting in the formation of poly(ethylene glycol-co-ester). In another example, polyester-based diol oligomers can be obtained through a similar process using polycaprolactone (PCL) or other types of polyesters having molecular weights ranging from about 500 to about 5,000 g / mol.

[0034] In another example, the starting material includes one or more perfluoropolyethers, such as an HO-PEG-PFPE-PEG-OH structure. These diol oligomers can be synthesized through a ring-opening reaction between PEG and PFPE diols at temperatures ranging from 50° C. to 100° C. over several hours, resulting in the formation of perfluoropolyether-based poly(ethylene glycol-block-perfluoropolyether). In another example, the diol oligomers can include polysiloxanes having molecular weights ranging from approximately 500 to about 5,000 g / mol. The foregoing reactions can be monitored by techniques such as gel permeation chromatography and nuclear magnetic resonance spectroscopy.

[0035] In all examples, it is useful to maintain precise control over reactant concentrations, temperature, pressure, and other process parameters during synthesis to ensure consistent molecular weight and properties of diol oligomers for subsequent extension reactions or applications in various industries, such as coatings, adhesives, sealants, and elastomers.

[0036] Various embodiments can be used to heat the diol oligomer to an optimal temperature range of about 90 to about 100°C under an inert atmosphere, depending on the specific reaction conditions and desired product properties. In one embodiment, the heating step is carried out in a three-neck flask equipped with a reflux condenser and two septa to allow efficient heat transfer while minimizing exposure to atmospheric oxygen or moisture. The diol oligomer may be dissolved in any solvent, such as tetrahydrofuran (THF), dichloromethane (DCM), or dimethylformamide (DMF), if necessary, before heating. In another embodiment, the reaction mixture is heated when the bisdimethylaminosilane compound is introduced stepwise into the reactor containing the diol oligomer over a period of 30 minutes to 1 hour. In yet another embodiment, a microwave-assisted heating method is employed using a dedicated reaction vessel specially designed for this purpose. The diol oligomer and bisdimethylaminosilane compound are mixed in a reactor under an inert atmosphere and then subjected to controlled microwave irradiation in a specific frequency range (e.g., 2-5 GHz) at a power level of 100-500 W. In a further example, an ultrasonically assisted heating method is used, in which high-frequency sound waves generated by a transducer or piezoelectric device are applied directly to the reaction mixture. This method allows for efficient heat transfer and mixing without introducing external mechanical stresses that could degrade the product quality. Regardless of the heating protocol selected, it is useful to maintain a constant temperature range of 90-100°C throughout the entire stretching process while minimizing exposure to atmospheric oxygen or moisture. In this way, diol oligomers with precisely controlled molecular weights can be achieved through a controlled condensation reaction without compromising their chemical stability and reactivity.

[0037] Slow addition of the bisdimethylaminosilane compound to the diol oligomer reaction mixture can be achieved through various experiments to optimize molecular weight control and product properties. In one example, the bisdimethylaminosilane species is introduced into a 250-mL flask containing approximately 100 g of a fluorochemical-based terminally functionalized precursor (e.g., HO-PEG-PFPE-PEG-OH) at an elevated temperature ranging from 90°C to 110°C. The rate of addition can be controlled by adjusting the flow rate or volumetric delivery system, allowing for gradual consumption of the bisdimethylaminosilane compound over approximately 30 minutes to 1 hour while maintaining optimal reaction conditions.

[0038] In another example, a gradual addition process is facilitated by the use of an automated dispensing device that precisely controls the amount and timing of bisdimethylaminosilane species introduction. This is achieved by programming a syringe pump or other precision dosing system to deliver small amounts (e.g., 0.1-10 mL) at regular intervals, ensuring consistent reaction conditions throughout the entire extension process.

[0039] In yet another embodiment, manual addition through the use of a syringe, dropper, or pipette is employed, allowing precise control over the delivery of the bisdimethylaminosilane compound and minimizing the potential contamination risks associated with automated systems. This approach is particularly useful when working with small-scale reactions (e.g., 10-50 mL), where precise dosing is more challenging. In yet another embodiment, the slow addition process is optimized by incorporating a temperature-controlled reaction vessel or heat transfer system to maintain optimal conditions during the introduction of the bisdimethylaminosilane compound. This can be achieved through the use of a thermally controlled reactor with precise temperature control (±0.1 °C) and / or an external heating / cooling system. In yet another embodiment, the slow addition process is further optimized by incorporating a gas flow or sparging system to maintain an inert atmosphere during the reaction conditions to minimize side reactions and decomposition products associated with atmospheric exposure. Sparging refers to the chemistry-related process of sparging a gas through a liquid to remove other gases or volatile compounds during a reaction process or step. This can be achieved through the use of nitrogen (N), argon (Ar), or other gases as reactants. In yet another example, the slow addition process is further optimized by incorporating a mechanical stirring device, such as a magnetic stir bar, overhead mixer, or impeller, to ensure uniform mixing and reaction conditions throughout the stretch reaction. This is particularly useful when working with viscous materials or large-scale reactors where flow patterns become more complex. These examples demonstrate various methods for achieving optimal slow addition of the bisdimethylaminosilane compound with stirring during the diol oligomer stretch process, allowing for precise control of molecular weight gain and product properties under a wide range of reaction conditions.

[0040] The final sparging step of the extension reaction involves introducing nitrogen (N2) into the reactor to remove residual dimethylamine by-products and maintain an inert atmosphere during extension of the diol oligomer chain. This useful step ensures the elimination of all dissolved bisdimethylaminosilane compounds, thereby preventing unwanted side reactions when the extended diol resin is used in subsequent compositions. In one example, the nitrogen gas flow rate is controlled between 0.1 and 10 standard liters per minute (SLPM) to achieve optimal sparging conditions for efficient removal of dimethylamine by-products and maintenance of an inert atmosphere. In another example, N2 gas is introduced through an inlet located at least 5 cm above the surface of the reaction mixture to prevent entrainment or contamination. In a further example, multiple nitrogen inlets can be used simultaneously, with the flow rate controlled between 0.1 and 10 SLPM for each inlet, to bubble the inert gas through the solution during the reaction to push out the dissolved dimethylamine. In yet another example, an N2 gas pressure regulator is used to maintain a constant flow within the reaction vessel during sparging. In some embodiments, the nitrogen flow rate can be adjusted based on real-time monitoring of reactant concentrations or product characteristics using techniques such as infrared spectroscopy (IR), nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry (MS), and gas chromatography-mass spectrometry (GC-MS). In other embodiments, the sparging step can be carried out at different temperatures between 20°C and 100°C or at pressures up to 10 bar. In one embodiment, a combination of nitrogen flow rate control and temperature regulation is used during sparging. For example, increasing the N2 gas flow rate to 0.1-5 SLPM while maintaining ambient reaction temperature (25°C) can increase the efficiency of dimethylamine removal and minimize product degradation. In another embodiment, reducing the N2 gas flow rate to less than 0.01 SLPM at higher reaction temperatures of approximately 80°C can be beneficial to reduce side reactions or by-product formation. In some embodiments, sparging with nitrogen is carried out in combination with other techniques, such as vacuum distillation, centrifugation, and / or filtration steps following the stretching process. In such cases, precise control over the N2 flow rate can help optimize product purity while minimizing waste production.

[0041] An exemplary method for producing a stretched diol composition can include providing a diol oligomer to a reaction vessel, wherein the diol oligomer has an average molecular weight of about 500 to about 5,000 g / mol, heating the diol oligomer to a temperature of about 50 to about 110°C in an inert atmosphere, and adding a bisdimethylaminosilane compound with stirring. The method for producing a stretched diol composition can further include maintaining a molar excess of the diol oligomer relative to the bisdimethylaminosilane compound and heating the diol oligomer to a temperature between 90°C and 100°C while adding the bisdimethylaminosilane compound over a period of 30 to 60 minutes. Heating is then continued for about 1 hour to about 4 hours. Finally, following stretching, the reaction solution is sparged with nitrogen gas to remove any residual dimethylamine by-product. As noted above, methods for making the extended diol composition can include where the diol oligomer is selected from polyoxymethylene, polyethylene glycol, polyethylene tetramethylene glycol, and perfluoropolyether, and the bisdimethylaminosilane compound includes 1,2-bis(dimethylamine)tetramethyldisilane, as well as variants of the aforementioned methyl, vinyl, or phenyl functional groups.

[0042] While the present teachings have been illustrated with respect to one or more embodiments, changes and / or modifications can be made to the illustrated examples without departing from the spirit and scope of the claims. For example, while a process is described as a series of acts or events, it should be understood that the present teachings are not limited by the ordering of such acts or events. Some acts may occur in a different order than described herein and / or concurrently with acts or events other than those described herein. Also, not all process steps are required to implement a methodology in accordance with one or more aspects or embodiments of the present teachings. It should be understood that structural objects and / or processing steps may be added, or existing structural objects and / or processing steps may be removed or modified. Furthermore, one or more of the acts described herein may be performed in one or more separate acts and / or phases. Furthermore, to the extent that the terms "including," "includes," "having," "has," "with," or variations thereof are used in either the detailed description or the claims, such terms are intended to be as inclusive as the term "comprising." The phrase "at least one of" is used to mean that one or more of the listed items may be selected. Furthermore, in this specification and claims, the term "on" when used in connection with two materials, such as one "on" the other, means that there is at least some contact between the materials, whereas "over" means that the materials are in close proximity to each other but may involve one or more additional intervening materials, e.g., contact is possible but not required. Neither "on" nor "over" imply any directionality when used herein. The term "conformal" describes a coating material in which the angle of the underlying material is preserved by the conformal material.The term "about" indicates that the recited value may be varied somewhat without causing incompatibility of the process or structure with the illustrated embodiment. The terms "couple," "coupled," "connect," "connection," "connected," "in connection with," and "connecting" refer to "directly connected with" or "connected with via one or more intermediate elements or members." Finally, the term "example" or "exemplary" indicates that the description is used as an example, rather than to imply ideality. Other embodiments of the present teachings will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure herein. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the present teachings being indicated by the following claims.

Claims

1. 1. A stretched diol composition comprising: a first component comprising a diol oligomer; and a second component comprising a bisdimethylaminosilane species, wherein the first component is in molar excess relative to the second component, and the diol oligomer has a number average molecular weight Mn of about 500 g / mol to about 5,000 g / mol; 1. A stretched diol composition comprising:

2. 2. The stretched diol composition of claim 1, wherein the diol oligomer is terminated with α,ω-hydroxyl groups.

3. The diol oligomer is and R groups containing polyether or polyester The stretched diol composition of claim 1 comprising:

4. The bisdimethylaminosilane species is and Both are the same, CH ３ R selected from the group consisting of , vinyl, and phenyl １ and R ２ The stretched diol composition of claim 1 comprising:

5. The bisdimethylaminosilane species is and Different from each other, CH ３ R selected from the group consisting of , vinyl, and phenyl １ and R ２ The stretched diol composition of claim 1 comprising:

6. 10. The stretched diol composition of claim 1, further comprising a terminally functionalized HO-PEG-PFPE-PEG-OH structure.

7. The extended diol composition of claim 3 , wherein the polyether comprises a perfluoropolyether.

8. the polyether is selected from the group consisting of polyoxymethylene, polyethylene glycol, polytetramethylene glycol, poly(propanediol), and perfluoropolyether; the polyester is selected from the group consisting of poly(caprolactone), poly(lactic acid), and poly(glycolic acid); The stretched diol composition of claim 3.

9. The extended diol composition of claim 1 , wherein the bisdimethylaminosilane species comprises a disilane compound.

10. The extended diol composition of claim 1, wherein the bisdimethylaminosilane species comprises 1,2-bis(dimethylamine)tetramethyldisilane.

11. 10. The extended diol composition of claim 1, wherein the molar ratio of said second component to said first component is from about 0.01:1 to about 0.99:

1.

12. 10. The stretched diol composition of claim 1 comprising a molecular weight distribution having a number average molecular weight Mn of about 5,000 to about 50,000 g / mol.

13. 1. A stretched diol composition comprising: a first component comprising a diol oligomer; A second component comprising a bisdimethylaminosilane species Including, the first component is in molar excess relative to the second component; the diol oligomer has a number average molecular weight Mn of about 500 g / mol to about 5,000 g / mol; the stretched diol composition has a number average molecular weight Mn greater than 5,000 g / mol; The bisdimethylaminosilane species is: Including, In the above formula, R １ and R ２ is CH ３ , vinyl, phenyl; Stretched diol composition.

14. The diol oligomer is: and R groups containing polyether or polyester The stretched diol composition of claim 13, comprising:

15. The extended diol composition of claim 13, wherein the bisdimethylaminosilane species comprises 1,2-bis(dimethylamine)tetramethyldisilane.

16. 14. The extended diol composition of claim 13, wherein the molar ratio of the second component to the first component is from about 0.01:1 to about 0.99:

1.

17. 14. The stretched diol composition of claim 13, comprising a molecular weight distribution having a number average molecular weight Mn of about 5,000 to about 50,000 g / mol.

18. 1. A method for making an extended diol composition, comprising: providing a diol oligomer to a reaction vessel, the diol oligomer having an average molecular weight of about 500 to about 5,000 g / mol; heating the diol oligomer in an inert atmosphere at a temperature of about 50 to about 110°C; adding the bisdimethylaminosilane compound with stirring; 1. A method for making an extended diol composition, comprising:

19. maintaining a molar excess of the diol oligomer relative to the bisdimethylaminosilane compound; heating the diol oligomer at a temperature between 90°C and 100°C for about 1 hour to about 4 hours; sparging the reaction vessel with nitrogen gas while adding the bisdimethylaminosilane to remove any residual dimethylamine by-product; 20. The method for making the stretched diol composition of claim 18, further comprising:

20. the diol oligomer is selected from polyoxymethylene, polyethylene glycol, polyethylenetetramethylene glycol, and perfluoropolyether; the bisdimethylaminosilane compound includes 1,2-bis(dimethylamine)tetramethyldisilane; 20. A method for making the stretched diol composition of claim 18.

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