Electrostatic dissipative thermoplastic polyurethane compositions

Abstract

This invention relates to thermoplastic polyurethane compositions with electrostatic dissipation, wherein the thermoplastic polyurethane is combined with an electrostatic dissipation additive comprising an imidazolium liquid salt.

Description

Background Technology

[0001] This invention relates to electrostatic dissipation heat dissipation plastic polyurethane (TPU) compositions.

[0002] It is well known that electrostatic charges form and remain on the surfaces of most plastics. Many plastic materials have a significant tendency to accumulate electrostatic charges due to their low electrical conductivity. This type of electrostatic charge formation and retention can be problematic. For example, the presence of electrostatic charges on thermoplastic film sheets can cause the sheets to adhere to each other, making them more difficult to separate for further processing. Furthermore, the presence of electrostatic charges can cause dust to adhere to items, such as those packaged in plastic bags, which can diminish any sales appeal.

[0003] The increasing complexity and sensitivity of microelectronic devices have made electrostatic discharge (ESD) control a particular concern in the electronics industry. Even low-voltage discharges can cause severe damage to sensitive devices. The need to control the accumulation and dissipation of static charge often requires the entire assembly environment of these devices to be constructed of partially conductive materials and / or ESD-dissipating (or discharge) materials. ESD-protective packaging, handling cases, enclosures, and lids made of conductive polymer materials may also be required for storing, transporting, protecting, or supporting electrical devices and equipment.

[0004] The accumulation of electrostatic charge on plastics during manufacturing or use has been prevented through the use of various ESD additives, such as antistatic agents and ESD components. These additives can be applied as coatings, which can be sprayed or dipped onto the article after manufacturing, although this method typically produces a temporary solution. Alternatively, these materials can be incorporated into the polymer used to manufacture the article during processing, thereby providing a greater degree of durability.

[0005] TPU materials possess a variety of properties desired for various applications; however, some TPU materials have been found to be unsuitable for applications requiring ESD protection. Therefore, there is a need for TPU compositions that possess ESD protection as well as known physical properties typically attributable to the TPU material. Summary of the Invention

[0006] This invention provides an electrostatic dissipation thermoplastic polyurethane (ESD-TPU) composition comprising a thermoplastic polyurethane and an electrostatic dissipation additive. The thermoplastic polyurethane comprises a reaction product of a polyol intermediate, a diisocyanate, and a chain extender. In one embodiment, the electrostatic dissipation additive is an imidazolium liquid salt. In another embodiment, the electrostatic dissipation additive is propylene carbonate. In yet another embodiment, the electrostatic dissipation additive is a mixture of an imidazolium liquid salt and propylene carbonate.

[0007] For example, in one embodiment, the electrostatic heat dissipation plastic polyurethane composition comprises (i) a thermoplastic polyurethane prepared by reacting a polyester polyol intermediate, a diisocyanate, and a chain extender, and (ii) an electrostatic heat dissipation additive comprising an imidazolium liquid salt and propylene propionate. As another example, the electrostatic heat dissipation plastic polyurethane composition comprises (i) a thermoplastic polyurethane prepared by reacting a polyether polyol intermediate, a diisocyanate, and a chain extender, and (ii) an electrostatic heat dissipation additive comprising an imidazolium liquid salt. Detailed Implementation

[0008] The various features and embodiments of the present invention will now be described in a non-limiting manner.

[0009] thermoplastic polyurethane

[0010] The thermoplastic polyurethane (TPU) polymer used in this invention is prepared by reacting three reactants. The first reactant is a polyol intermediate, the second reactant is a diisocyanate, and the third reactant is a chain extender. Each of the three reactants is discussed below.

[0011] polyol intermediates

[0012] In one embodiment, the polyol intermediate used to prepare the thermoplastic polyurethane of the present invention is a polyester polyol intermediate. The polyester polyol is prepared by reacting a dialkylene glycol with a dicarboxylic acid or its ester or anhydride.

[0013] The polyester polyol intermediate used in this invention may include at least one terminal hydroxyl group, and in some embodiments, at least one terminal hydroxyl group and one or more carboxylic acid groups. In another embodiment, the polyester polyol intermediate comprises two terminal hydroxyl groups, and in some embodiments, two hydroxyl groups and one or more or two carboxylic acid groups. The polyester polyol intermediate is generally a substantially linear or linear polyester having a number average molecular weight (Mn) of about 500 to about 10,000, about 500 to about 5,000, about 1,000 to about 3,000, or about 2,000.

[0014] In some embodiments, the polyester polyol intermediate may have a low acid value, such as less than 1.5, less than 1.0, or even less than 0.8. The low acid value of the polyester polyol intermediate can generally provide improved hydrolytic stability in the resulting TPU polymer. The acid value can be determined according to ASTM D-4662 and is defined as the amount of alkali required, expressed as the number of milligrams of potassium hydroxide needed to titrate 1.0 gram of acidic component in the sample. Hydrolytic stability can also be improved by adding a hydrolysis stabilizer to the TPU, as is known to those skilled in the art of formulating TPU polymers.

[0015] The diallyl glycols suitable for preparing the polyester polyol intermediates of the present invention can be aliphatic, cycloaliphatic, aromatic, or combinations thereof. Suitable glycols may contain 2, 4, 6 to 20, 14, 8, 6, or 4 carbon atoms, and in some embodiments may contain 2 to 12, 2 to 8, 6, 4 to 6, or even 4 carbon atoms. In some embodiments, the diallyl glycols include oxydiethanol, diethylene glycol, dipropylene glycol, 3,3-oxydiprop-1-ol, dibutanediol, or combinations thereof. In other embodiments, one or more of the listed diallyl glycols may be excluded from the present invention. Blends of two or more glycols may be used. In some embodiments, monoalkylene glycols may be used in combination with the aforementioned diallyl glycols. In other embodiments, the glycols used to prepare the polyester polyol intermediates do not contain monoalkylene glycols.

[0016] The dicarboxylic acid suitable for preparing the polyester polyol intermediates of the present invention can be aliphatic, cycloaliphatic, aromatic, or a combination thereof. Suitable acids may contain 2, 4, or 6 to 20, 15, 8, or 6 carbon atoms, and in some embodiments may contain 2 to 15, 4 to 15, 4 to 8, or even 6 carbon atoms. In some embodiments, the dicarboxylic acid includes succinic acid, glutaric acid, adipic acid, pimelic acid, octanoic acid, azelaic acid, sebacic acid, dodecanoic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, or a combination thereof. In other embodiments, one or more of the listed dicarboxylic acids may be excluded from the present invention.

[0017] The polyester polyol intermediates of the present invention may also be derived from one or more of the above-mentioned dicarboxylic acids, esters or anhydrides, or combinations thereof. Suitable anhydrides include succinic anhydride, alkyl and / or alkenyl succinic anhydride, phthalic anhydride, and tetrahydrophthalic anhydride. In some embodiments, the acid is adipic acid. Blends of two or more acids may be used.

[0018] The polyester polyol intermediates of the present invention are prepared by reacting one or more of the aforementioned diallyl glycols with one or more of the aforementioned dicarboxylic acids and / or one or more of their esters or anhydrides. In some embodiments, more than one equivalent of glycol is used for each amount of acid. The preparation comprises: (1) an esterification reaction of one or more diallyl glycols with one or more dicarboxylic acids or anhydrides or (2) a transesterification reaction, i.e., a reaction of one or more diallyl glycols with a dicarboxylic acid ester. To obtain a linear chain with terminal hydroxyl groups predominating, a molar ratio of glycol to acid greater than one mole is generally preferred.

[0019] In another embodiment, the polyol intermediate used to prepare the thermoplastic polyurethane of the present invention is a polyether polyol. Polyether polyol intermediates include polyether polyols derived from diols or polyols having a total of 2 to 15 carbon atoms, and in some embodiments, alkyl diols or glycols reacting with an ether containing an alkylene oxide (typically ethylene oxide or propylene oxide or mixtures thereof) having 2 to 6 carbon atoms. For example, hydroxyl-functionalized polyethers can be prepared by first reacting propylene glycol with propylene oxide, followed by a reaction with ethylene oxide. The primary hydroxyl groups produced by ethylene oxide are more reactive than secondary hydroxyl groups and are therefore preferred. Available commercial polyether polyols include poly(ethylene glycol) containing ethylene oxide reacted with ethylene glycol, poly(propylene glycol) containing propylene oxide reacted with propylene glycol, and poly(tetramethylene ether glycol) containing water reacted with tetrahydrofuran, which can also be described as polytetrahydrofuran and is commonly referred to as PTMEG. In some embodiments, the polyether intermediate comprises PTMEG. Suitable polyether polyols also include polyamide adducts of epoxides and may include, for example, ethylenediamine adducts comprising the product of the reaction of ethylenediamine and propylene oxide, diethylenetriamine adducts comprising the product of the reaction of diethylenetriamine and propylene oxide, and similar polyamide-type polyether polyols. Coethers may also be used in the compositions. Typical coethers comprise the product of the reaction of THF and ethylene oxide or THF and propylene oxide. These can be purchased from BASF, such as the block copolymer PolyTHF. ® B and random copolymer PolyTHF ® R. Various polyether intermediates typically have a number-average molecular weight (Mn) determined by measuring terminal functional groups, with an average molecular weight greater than about 700, such as about 700 to about 10,000, about 1,000 to about 5,000, or about 1,000 to about 2,500. In some embodiments, the polyether intermediate comprises a blend of two or more polyethers with different molecular weights, such as a blend of 2,000 Mn and 1,000 Mn PTMEG.

[0020] In some embodiments, the polyol intermediate comprises or is composed of polyester polyols. In this invention, the polyol intermediate comprises or is composed of polyether polyols. Mixtures of polyester polyols and / or polyether polyols are also within the scope of this invention.

[0021] diisocyanate

[0022] The second reactant used in the preparation of the TPU of the present invention is a diisocyanate. Suitable diisocyanates include: (i) aromatic diisocyanates, such as 4,4'-methylenebis(phenyl isocyanate) (MDI), isophenyl diisocyanate (XDI), phenylene-1,4-diisocyanate, 1,5-naphthalene diisocyanate, diphenylmethane-3,3'-dimethoxy-4,4'-diisocyanate (TODI), and toluene diisocyanate (TDI); and (ii) aliphatic diisocyanates, such as isophorone diisocyanate (IPDI), 1,4-cyclohexyl diisocyanate (CHDI), decane-1,10-diisocyanate, hexamethylene diisocyanate (HDI), and dicyclohexylmethane-4,4'-diisocyanate. In some embodiments, the diisocyanate is 4,4'-methylenebis(phenyl isocyanate) (MDI). In other embodiments, one or more of the listed diisocyanates may be excluded from the present invention.

[0023] Mixtures of two or more diisocyanates can be used. Additionally, small amounts of isocyanates with a functionality greater than 2, such as triisocyanates, can be used in conjunction with diisocyanates. Large amounts of isocyanates with a functionality of 3 or greater should be avoided, as they will cause crosslinking of the TPU polymer.

[0024] Chain extender

[0025] The third reactant in the thermoplastic polyurethane used in this invention is a chain extender component. Suitable chain extenders include diols, and may be aliphatic, aromatic, or combinations thereof. In some embodiments, the chain extender is a diol having 2 to about 12 carbon atoms.

[0026] In some embodiments, the diol chain extender is a lower aliphatic or short-chain diol having about 2 to about 10 carbon atoms, and includes, for example, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,3-butanediol, 1,5-pentanediol, 1,4-cyclohexanediol, neopentanediol, etc. In some embodiments, the chain extender includes 1,4-butanediol.

[0027] Aromatic glycols can also be used as chain extenders to prepare TPU, including phenylene glycol and xylene glycol. Xylene glycol is a mixture of 1,4-di(hydroxymethyl)benzene and 1,2-di(hydroxymethyl)benzene. Phenylene glycols specifically include hydroquinone, bis(β-hydroxyethyl) ether, also known as 1,4-di(2-hydroxyethoxy)benzene; resorcinol, bis(β-hydroxyethyl) ether, also known as 1,3-di(2-hydroxyethyl)benzene; catechol, bis(β-hydroxyethyl) ether, also known as 1,2-di(2-hydroxyethoxy)benzene; and combinations thereof.

[0028] A mixture of two or more diols may be used as a chain extender in the TPU of the present invention. In some embodiments, the chain extender is a mixture of 1,4-butanediol and 1,6-hexanediol. In other embodiments, one or more of the listed chain extenders may be excluded from the present invention.

[0029] Diamines can also be used as chain extenders, as is well known in the art. In one embodiment of the invention, the chain extender comprises a combination of a diamine as a co-chain extender and one or more of the above-mentioned chain extenders. In other embodiments, the invention does not use any diamine in the preparation of its compositions.

[0030] preparation TPU Method

[0031] Three reactants (polyol intermediate, diisocyanate, and chain extender) are reacted together to form the TPU of the present invention. Any known process for reacting these three reactants can be used to manufacture TPU. In one embodiment, the method is a so-called "one-step" process in which all three reactants are added to an extruder reactor and reacted. The equivalent weight ratio of the diisocyanate to the total equivalent weight of the hydroxyl-containing component (i.e., the polyester polyol intermediate and the chain extender diol) can be from about 0.95 to about 1.10, or from about 0.96 to about 1.02, and even from about 0.97 to about 1.005. The reaction temperature using a urethane catalyst can be from about 175°C to about 245°C, and in other embodiments from 180°C to 220°C.

[0032] Typically, diisocyanates can be reacted with polyester polyol intermediates or chain extenders using any conventional catalyst. Examples of suitable catalysts include various alkylamines, alkyl ethers, or alkyl thiols ethers of bismuth or tin, wherein the alkyl moiety has 1 to approximately 20 carbon atoms; specific examples include bismuth octanoate, bismuth laurate, etc. Preferred catalysts include various tin catalysts, such as stannous octanoate, dibutyltin dioctanoate, dibutyltin dilaurate, etc. The amount of such catalysts is typically small, such as from about 20 parts per million parts to about 200 parts per million parts based on the total weight of the reactants forming the polyurethane.

[0033] This TPU can also be prepared using a prepolymer process. In the prepolymer pathway, a polyester polyol intermediate is typically reacted with an equivalence excess of one or more diisocyanates to form a prepolymer solution containing free or unreacted diisocyanates. The reaction is typically carried out in the presence of a suitable urethane catalyst at temperatures of about 80°C to about 220°C, or about 150°C to about 200°C. Subsequently, a chain extender, as indicated above, is added in an equivalence typically equal to that of the isocyanate end groups and any free or unreacted diisocyanate compounds. Thus, the overall equivalence ratio of total diisocyanates to the total equivalence of the hydroxyl-terminated polyester and the chain extender is about 0.95 to about 1.10, or about 0.96 to about 1.02, and even about 0.97 to about 1.05. The chain extension reaction temperature is typically about 180°C to about 250°C or about 200°C to about 240°C. Generally, the prepolymer pathway can be carried out in any conventional apparatus, including an extruder. In such embodiments, a polyester polyol intermediate is reacted with an equivalent excess of diisocyanate in the first section of an extruder to form a prepolymer solution, and subsequently, a chain extender is added in a downstream section and reacts with the prepolymer solution. Any conventional extruder can be used, including extruders equipped with a barrier screw having a length-to-diameter ratio of at least 20, and in some embodiments at least 25.

[0034] In one embodiment, the components are mixed in a single-screw or twin-screw extruder having multiple heating zones and multiple feed ports, between its feed end and its die end. Components can be added at one or more feed ports, and the resulting TPU composition exiting the extruder die end can be granulated.

[0035] In some embodiments, component (a), the polyester polyol intermediate, includes poly(diethylene adipate), component (b), the diisocyanate, including 4,4'-methylene bis-(phenyl isocyanate), and component (c), the chain extender, includes butanediol, HQEE (hydroquinone bis(2-hydroxyethyl) ether), or combinations thereof.

[0036] The ESD additives described herein can be combined with TPU in any manner or method understood by those skilled in the art, whether now known or to be developed in the future. For example, ESD additives can be incorporated in situ into TPU compositions during TPU synthesis or can be compounded with previously prepared TPU.

[0037] Static dissipation additives

[0038] The electrostatic dissipation heat-dissipating plastic polyurethane composition of the present invention further comprises an electrostatic dissipation additive. In one embodiment, the electrostatic dissipation additive comprises or is composed of an imidazolium liquid salt. The imidazolium salt is made from discrete organic cation and anion pairs. In the present invention, the organic cation comprises or is composed of an imidazolium cation. Examples of useful imidazolium liquid salts include 1-methyl-3-octylimidazolium chloride; 1-methyl-3-octylimidazolium bromide; 1-methyl-3-octylimidazolium iodide; 1-methyl-3-octylimidazolium hexafluorophosphate; 1-methyl-3-octylimidazolium tetrafluoroborate; 1-methyl-3-octylimidazolium hexafluoroantimonate; 1-methyl-3-octylimidazolium trifluoromethanesulfonate; 1-methyl-3-octylimidazolium methyl sulfate; 1-methyl-3-octylimidazolium ethyl sulfate; 1-methyl-3-octylimidazolium acetate; 1-methyl-3-octylimidazolium thiocyanate; and 1-methyl-3-octylimidazolium dicyandiamide. 1-Methyl-3-octylimidazolium bis(trifluoromethanesulfonyl)amide; 1-Butyl-3-methylimidazolium tetrafluoroborate; 1-Octyl-2,3-dimethylimidazolium chloride; 1-Octyl-2,3-dimethylimidazolium bromide; 1-Octyl-2,3-dimethylimidazolium iodide; 1-Octyl-2,3-dimethylimidazolium hexafluorophosphate; 1-Octyl-2,3-dimethylimidazolium tetrafluoroborate; 1-Octyl-2,3-dimethylimidazolium hexafluoroantimonate; 1-Octyl-2,3-dimethylimidazolium trifluoromethanesulfonate; 1-Octyl-2,3-dimethylimidazolium methyl sulfate; 1-Octyl-2,3-dimethylimidazolium Ethyl sulfate; 1-Octyl-2,3-dimethylimidazolium acetate; 1-Octyl-2,3-dimethylimidazolium thiocyanate; 1-Octyl-2,3-dimethylimidazolium dicyanamide; 1-Octyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)amide; 1-Ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide; 1-Decyl-3-methylimidazolium chloride; 1-Decyl-3-methylimidazolium bromide; 1-Decyl-3-methylimidazolium iodide; 1-Decyl-3-methylimidazolium hexafluorophosphate; 1-Decyl-3-methylimidazolium tetrafluoroborate; 1-Decyl-3-methylimidazolium hexafluoroantimonate; 1-Decyl-3-methylimidazolium trifluoromethanesulfonate; 1-Decyl-3-methylimidazolium methyl sulfate; 1-Decyl-3-methylimidazolium ethyl sulfate; 1-Decyl-3-methylimidazolium acetate; 1-Decyl-3-methylimidazolium thiocyanate; 1-Decyl-3-methylimidazolium dicyanamide; 1-Decyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide; 1-Ethyl-3-methylimidazolium ethyl sulfate; 1-Dodecyl-3-methylimidazolium chloride; 1-Dodecyl-3-methylimidazolium bromide; 1-Dodecyl-3-methylimidazolium iodide; 1-Dodecyl-3-methylimidazolium hexafluorophosphate;1-Dodecyl-3-methylimidazolium tetrafluoroborate; 1-Dodecyl-3-methylimidazolium hexafluoroantimonate; 1-Dodecyl-3-methylimidazolium trifluoromethanesulfonate; 1-Dodecyl-3-methylimidazolium methyl sulfate; 1-Dodecyl-3-methylimidazolium ethyl sulfate; 1-Dodecyl-3-methylimidazolium acetate; 1-Dodecyl-3-methylimidazolium thiocyanate; 1-Dodecyl-3-methylimidazolium dicyandiamide; 1-Dodecyl-3-methylimidazolium bis(trifluoro) Methylsulfonyl amide; 1-Tetradecyl-3-methylimidazolium chloride; 1-Tetradecyl-3-methylimidazolium bromide; 1-Tetradecyl-3-methylimidazolium iodide; 1-Tetradecyl-3-methylimidazolium hexafluorophosphate; 1-Tetradecyl-3-methylimidazolium tetrafluoroborate; 1-Tetradecyl-3-methylimidazolium hexafluoroantimonate; 1-Tetradecyl-3-methylimidazolium trifluoromethanesulfonate; 1-Tetradecyl-3-methylimidazolium methyl sulfate; 1-Tetradecyl-3-methylimidazolium... 1-Tetradecyl-3-methylimidazolium ethyl sulfate; 1-Tetradecyl-3-methylimidazolium acetate; 1-Tetradecyl-3-methylimidazolium thiocyanate; 1-Tetradecyl-3-methylimidazolium dicyanamide; 1-Tetradecyl-3-methylimidazolium bis(trifluoromethylsulfonyl)amide; 1-Hexadecyl-3-methylimidazolium chloride; 1-Hexadecyl-3-methylimidazolium bromide; 1-Hexadecyl-3-methylimidazolium iodide; 1-Hexadecyl-3-methylimidazolium hexafluorophosphate; 1-Hexadecyl-3-methylimidazolium... 1-Methylimidazolium tetrafluoroborate; 1-Hexadecyl-3-methylimidazolium hexafluoroantimonate; 1-Hexadecyl-3-methylimidazolium trifluoromethanesulfonate; 1-Hexadecyl-3-methylimidazolium methyl sulfate; 1-Hexadecyl-3-methylimidazolium ethyl sulfate; 1-Hexadecyl-3-methylimidazolium acetate; 1-Hexadecyl-3-methylimidazolium thiocyanate; 1-Hexadecyl-3-methylimidazolium dicyanamide; 1-Hexadecyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide.

[0039] In this invention, imidazolium liquid salt is added to thermoplastic polyurethane in an amount of 0.5 parts / 100 to 25 parts / 100, or 1 part / 100 to 20 parts / 100, or even 1 part / 100 to 16 parts / 100 (based on 100 parts of thermoplastic polyurethane).

[0040] In another embodiment, the invention includes a co-solvent in addition to the imidazolium liquid salt. Suitable co-solvents include ethylene carbonate, propylene carbonate, dimethyl sulfoxide, tetramethylene sulfone, triethylene glycol dimethyl ether and tetraethylene glycol dimethyl ether, γ-butyrolactone, and N-methyl-2-pyrrolidone. Specifically, it has been surprisingly found that propylene carbonate reduces the surface resistivity of thermoplastic polyurethane compositions.

[0041] In one embodiment of the invention, propylene carbonate is added to the thermoplastic polyurethane in an amount of 5 to 40 parts per 100 parts or 10 to 30 parts per 100 parts (based on 100 parts of thermoplastic polyurethane).

[0042] In some embodiments of the invention, the thermoplastic polyurethane composition is substantially free of or contains no or all metal-containing salts, such as lithium salts. As used herein, “substantially free” means that the amount of the substance in question is below a level that would affect fluid-related properties in a measurable manner. “Substantially free” can also mean that the substance in question was not intentionally added to the composition, but does not exclude the presence of such materials as contaminants. “Substantially free” can also mean that the substance in question may be present in amounts below the detection limits of standard test methods now known to or developed by those skilled in the art. In some embodiments, “substantially free” can mean less than 10 ppm by weight or even less than 5 ppm by weight.

[0043] The ESD-TPU compositions of the present invention have improved ESD properties compared to other ESD-TPU compositions, and in some embodiments, the combination of imidazolium liquid salt and propylene carbonate solvent shows a synergistic improvement in ESD properties.

[0044] In some embodiments, the ESD-TPU polymer composition of the present invention has a content of not greater than or less than 1.0 × 10⁻⁶. 8 Surface resistivity in ohms / square, and / or not greater than or less than 1.0 × 10⁻⁶ 7 Ohm-square volume resistivity.

[0045] The electrostatic dissipation composition of the present invention may have several embodiments. For example, the present invention is an electrostatic dissipation thermoplastic polyurethane composition comprising: (a) a thermoplastic polyurethane comprising a reaction product of a polyester polyol intermediate, a diisocyanate, and a chain extender; (b) an imidazolium liquid salt; and (c) propylene carbonate, wherein the imidazolium liquid salt is selected from: 1-ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, 1-butyl-3-methylimidazolium tetraborate, and the like. The mixture comprises, wherein propylene carbonate is added to the thermoplastic polyurethane in an amount of 5 to 40 parts or 10 to 30 parts per 100 parts, based on the thermoplastic polyurethane, and imidazolium liquid salt is added to the thermoplastic polyurethane in an amount of 0.5 to 25 parts per 100 parts, 1 to 20 parts per 100 parts, or 2 to 16 parts per 100 parts, based on the thermoplastic polyurethane. In another example of the invention, the electrostatic dissipation thermoplastic polyurethane composition comprises: (a) a thermoplastic polyurethane comprising a reaction product of a polyester polyol intermediate, 4,4'-methylene bis-(phenyl isocyanate) and 1,4-butanediol; (b) an imidazolium liquid salt; and (c) propylene carbonate, wherein the imidazolium liquid salt is selected from: 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, 1-butyl-3-methylimidazolium Tetraborates and mixtures thereof, wherein propylene carbonate is added to the thermoplastic polyurethane in an amount of 5 to 40 parts or 10 to 30 parts per 100 parts, and imidazolium liquid salt is added to the thermoplastic polyurethane in an amount of 0.5 to 25 parts per 100 parts, 1 to 20 parts per 100 parts, or 2 to 16 parts per 100 parts, based on the thermoplastic polyurethane. In yet another example, the present invention is an electrostatic dissipation thermoplastic polyurethane composition comprising: (a) a thermoplastic polyurethane comprising a reaction product of a polyether polyol intermediate, a diisocyanate, and a chain extender, and (b) an imidazodium liquid salt, wherein the imidazodium liquid salt is 1-butyl-3-methylimidazodium tetrafluoroborate, wherein the imidazodium liquid salt is added to the thermoplastic polyurethane in an amount of 0.5 parts / 100 to 25 parts / 100, or 1 part / 100 to 20 parts / 100, or 2 parts / 100 to 16 parts / 100, or 2 parts / 100 to 6 parts / 100, based on 100 parts of the thermoplastic polyurethane.In another example, the present invention is an electrostatic dissipation thermoplastic polyurethane composition comprising: (a) a thermoplastic polyurethane comprising a reaction product of a polyether polyol intermediate, 4,4'-methylene bis-(phenyl isocyanate) and 1,4-butanediol, and (b) an imidazolium liquid salt, wherein the imidazolium liquid salt is 1-butyl-3-methylimidazolium tetrafluoroborate, wherein the imidazolium liquid salt is added to the thermoplastic polyurethane in an amount of 0.5 parts / 100 to 25 parts / 100, or 1 part / 100 to 20 parts / 100, or 2 parts / 100 to 16 parts / 100, or 2 parts / 100 to 6 parts / 100, based on 100 parts of thermoplastic polyurethane.

[0046] Additional additives

[0047] The compositions of the present invention may also contain additional useful additives, wherein such additives may be used in suitable amounts. These optional additional additives include opaque pigments, colorants, mineral and / or inert fillers, stabilizers (including light stabilizers), lubricants, UV absorbers, processing aids, antioxidants, anti-ozone agents, and other additives as needed. Useful opaque pigments include titanium dioxide, zinc oxide, and titanate yellow. Useful colorants include carbon black, yellow oxides, brown oxides, raw ochre or calcined ochre or raw ochre or calcined ochre, chromium oxide green, cadmium pigments, chromium pigments, and other mixed metal oxides and organic pigments. Useful fillers include diatomaceous earth clay, silica, talc, mica, wollastonite, barium sulfate, and calcium carbonate. If desired, useful stabilizers, such as antioxidants, including phenolic antioxidants, may be used, while useful light stabilizers include organophosphates and organotin thiols (thiols). Useful lubricants include metal stearates, paraffin oils, and amide waxes. Useful UV absorbers include 2-(2'-hydroxyphenol)benzotriazole and 2-hydroxybenzophenone. Additives can also be used to improve the hydrolytic stability of TPU polymers. Each of these optional additives may be present in or excluded from the compositions of the present invention.

[0048] When present, these additional additives may be present in the compositions of the present invention at a rate of 0% or 0.01% to 5% or 2% by weight. These ranges may be applied individually to each additional additive present in the composition or to all additional additives present in total.

[0049] Blends containing polymers

[0050] The ESD-TPU polymer of the present invention can be blended with a matrix or base polymer to form polymer blends. These blends can also be prepared using the salt-modified ESD-TPU polymer described above.

[0051] As defined herein, a suitable base polymer can be a homopolymer or a copolymer. The base polymer can be a blend of multiple base polymers and may also include any of the aforementioned additional additives, including ESD additives. In some embodiments, the base polymers and / or compositions of the present invention are substantially free of or contain no ESD additives.

[0052] The base polymer may contain: (i) Polyolefins (PO), such as polyethylene (PE), polypropylene (PP), polybutene, ethylene propylene rubber (EPR), polyoxyethylene (POE), cyclic olefin copolymers (COC) or combinations thereof; (ii) Styrene-based materials, such as polystyrene (PS), acrylonitrile butadiene styrene (ABS), styrene-acrylonitrile (SAN), styrene-butadiene rubber (SBR or HIPS), poly-α-methylstyrene, methyl methacrylate-styrene (MS), styrene-maleic anhydride (SMA), styrene-butadiene copolymers (SBC) (such as styrene-butadiene-styrene copolymers (SBS) and styrene-ethylene / butadiene-styrene copolymers (SEBS)), styrene-ethylene / propylene-styrene copolymers (SEPS), styrene-butadiene latex (SBL), SAN (EPDM) modified with ethylene propylene diene monomer, and / or acrylic elastomers (e.g., PS-SBR copolymers) or combinations thereof; (iii) Thermoplastic polyurethane (TPU); (iv) Polyamides, such as Nylon ™ It includes polyamide 6,6 (PA66), polyamide 1,1 (PA11), polyamide 1,2 (PA12), copolyamide (COPA) or combinations thereof; (v) Acrylic polymers, such as polymethyl acrylate, polymethyl methacrylate, or combinations thereof; (vi) Polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), or combinations thereof; (vii) Polyoxymethylene, such as polyacetal; (viii) Polyesters, such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), copolyesters and / or polyester elastomers (COPE), including polyether-ester block copolymers, such as glycol-modified polyethylene terephthalate (PETG), polylactic acid (PLA) or combinations thereof. (ix) Polycarbonate (PC), polyphenylene sulfide (PPS), polyphenylene oxide (PPO) or combinations thereof; Or a combination of them.

[0053] As used herein, polyvinyl chloride (PVC), vinyl polymers, or vinyl polymer materials refer to homopolymers and copolymers of vinyl halides and vinylidenes, and include post-halogenated vinyl halides such as CPVC. Examples of these vinyl halides and vinylidenes are vinyl chloride, vinyl bromide, vinylidene chloride, etc. Vinyl halides and vinylidenes can be copolymerized with each other or each with one or more polymerizable olefin monomers having at least one terminal CH2=C< group. Examples of such olefin monomers may include α,β-olefinic unsaturated carboxylic acids, such as acrylic acid, methacrylic acid, ethylacrylic acid, α-cyanoacrylic acid, etc.; esters of acrylic acid, such as methyl acrylate, ethyl acrylate, butyl acrylate, octyl acrylate, cyanoethyl acrylate, hydroxyethyl acrylate, etc.; esters of methacrylic acid, such as methyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate, etc.; nitriles, such as acrylonitrile, methacrylonitrile, etc.; acrylamides, such as methacrylamide, N-hydroxymethylacrylamide, N-butoxymethylacrylamide, etc.; vinyl ethers, such as ethyl vinyl ether, chloroethyl vinyl ether, etc.; vinyl ketones; styrene and styrene derivatives, such as α-methylstyrene, vinyltoluene, chlorostyrene, etc.; vinylnaphthalene, allyl chloroacetate and vinyl chloroacetate, vinyl acetate, vinylpyridine, methyl vinyl ketone; dienes, including butadiene, isoprene, chloroprene, etc.; and other polymerizable olefin monomers of types known to those skilled in the art. In one embodiment, the base polymer includes polyvinyl chloride (PVC) and / or polyethylene terephthalate (PET).

[0054] Industrial applications

[0055] The compositions of the present invention (including the blends described above) can be used in a wide variety of applications. Some examples are tubing, paper pallets, floor tiles, machine housings, building and manufacturing equipment, and polymer sheets and films. More specifically, examples include fuel handling equipment, such as fuel lines and vapor return equipment, commercial equipment, coatings for floors (such as for cleanrooms and building areas), applications, cleanroom equipment (including clothing, flooring, mats, electronic packaging and housings), chip holders, chip tracks, transport boxes and transport box tops, medical applications, battery components (such as separators and / or partitions), and generally molded articles.

[0056] In one embodiment, the compositions of the present invention are used to prepare polymer articles used as: packaging materials for electronic components; internal battery separators for the construction of lithium-ion batteries; cleanroom supplies and building materials; antistatic conveyor belts; components for office equipment; antistatic clothing and shoes, or combinations thereof.

[0057] Electronic components include ESD-sensitive components, which include semiconductors. Articles of the invention can also be durable or consumable components for cleanroom equipment and applications. They also include building and / or construction materials for cleanrooms and data centers, which may include items such as soft walls, curtains, flooring, benches, etc. Articles of the invention also include laminated sheets, conveyor belts, or combinations thereof for manufacturing food, pharmaceutical, medical devices, and electronic components.

[0058] Furthermore, the compositions of the present invention can be used to prepare separators and other components for lithium-ion batteries, lithium polymer batteries, and fuel cells. Such uses of the compositions and articles of the present invention offer advantages over current batteries and fuel cells in terms of improved safety, performance, cost, or combinations thereof. The compositions of the present invention can be used to construct separator layers disposed between the anodes of a battery, as well as polymer electrolyte membranes.

[0059] The composition can be used with a variety of molding techniques, including injection molding, compression molding, slush molding, extrusion, thermoforming casting, rotational molding, sintering, and vacuum molding. Articles of the present invention can also be made from resins produced by suspension, bulk, emulsion, or solution methods.

[0060] It is known that some of the substances described above can interact in the final formulation, such that the composition of the final formulation may differ from those initially added. For example, metal ions (e.g., metal ions in detergents) can migrate to other acidic or anionic sites of other molecules. The resulting products, including those formed when the compositions of the present invention are used for their intended purpose, may not be easily described. However, all such modifications and reaction products are included within the scope of the present invention; the present invention includes compositions prepared by mixing the aforementioned components.

[0061] Example

[0062] The invention will be further illustrated by the following embodiments, which illustrate particularly advantageous implementations. While embodiments are provided to illustrate the invention, they are not intended to limit the invention.

[0063] Example

[0064] The TPU compositions were prepared from 4,4'-methylene bis-(phenyl isocyanate), 1,4-butanediol, and the polyol components shown in Table 1. Each TPU composition was then doped with the amounts of electrostatic dissipative additives shown (based on 100 parts of TPU, in parts per hundred parts (phr)), as shown in Table 1. ESD additive 1 (ADD 1) was a lithium salt of bis((trifluoromethyl)sulfonyl) azide, ESD additive 2 (ADD 2) was 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, and ESD additive 3 (ADD 3) was 1-butyl-3-methylimidazolium tetrafluoroborate.

[0065] Table 1

[0066] 1 ESD characteristics were measured using ASTM D-257 at 50% relative humidity (RH). The resistance results were formatted so that 1.0E+10 indicates 1.0 × 10⁻⁶. 10 The result is the same, and so on.

[0067] The results show that the ESD TPU polymer of the present invention has superior ESD properties compared to ESD TPUs using metals, and alternatively, the combination of imidazolium liquid salt and propylene carbonate exhibits an unexpected synergistic effect on ESD properties.

[0068] Each document mentioned above is incorporated herein by reference. Unless expressly indicated in the examples or otherwise elsewhere, all numerical quantities of material amounts, reaction conditions, molecular weights, carbon number, etc., specified in this specification should be understood as being modified by the word “about.” Unless otherwise specified, all percentage values, ppm values, and parts are based on weight. Unless otherwise stated, each chemical or composition mentioned herein should be interpreted as a commercial-grade substance that may contain isomers, byproducts, derivatives, and other such substances generally understood to be present in commercial-grade substances. However, unless otherwise stated, the amount of each chemical component does not include any solvents or diluents that are generally present in commercial substances. It should be understood that the upper and lower limits of the amounts, ranges, and proportions described herein can be combined independently. Similarly, the ranges and amounts of each element of the invention can be used in conjunction with the ranges or amounts of any other elements. As used herein, the expression “consisting substantially of…” allows for the inclusion of substances that do not materially affect the basic and novel properties of the composition under consideration.

Claims

1. A static dissipation heat dissipation plastic polyurethane composition, said polyurethane composition comprising: (a) A thermoplastic polyurethane, said thermoplastic polyurethane comprising a reaction product of a polyol intermediate, a diisocyanate, and a chain extender; and (b) Imidazolium liquid salt.

2. The polyurethane composition according to claim 1, wherein the polyol intermediate comprises or is composed of a polyester polyol intermediate.

3. The composition according to claim 2, wherein the polyester polyol intermediate comprises a reaction of a dialkylene glycol with a dicarboxylic acid or its ester or anhydride.

4. The composition according to claim 3, wherein the dicarboxylic acid contains 4 to 15 carbon atoms, and the dialkyldiol contains 2 to 8 carbon atoms.

5. The composition according to claim 3 or 4, wherein the dicarboxylic acid is selected from the group consisting of succinic acid, glutaric acid, adipic acid, pimelic acid, octanoic acid, azelaic acid, sebacic acid, dodecanoic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, and combinations thereof.

6. The composition according to any one of claims 2 to 5, wherein the dialkylene glycol is selected from the group consisting of: oxydiethanol, diethylene glycol, dipropylene glycol, 3,3-oxydiprop-1-ol, dibutanediol, and combinations thereof.

7. The composition according to any one of claims 2 to 6, wherein the composition further comprises a cosolvent selected from the group consisting of ethylene carbonate, propylene carbonate, dimethyl sulfoxide, tetramethylene sulfone, triethylene glycol dimethyl ether and tetraethylene glycol dimethyl ether, γ-butyrolactone, N-methyl-2-pyrrolidone, and mixtures thereof.

8. The composition according to claim 7, wherein the co-solvent comprises or is composed of propylene carbonate.

9. The composition according to claim 8, wherein the propylene carbonate is added to the thermoplastic polyurethane in an amount of 5 to 40 parts per 100 parts or 10 to 30 parts per 100 parts, based on 100 parts of the thermoplastic polyurethane.

10. The composition of claim 1, wherein the polyol intermediate comprises or is composed of a polyether polyol intermediate.

11. The composition according to any one of the preceding claims, wherein the diisocyanate is selected from the group consisting of: 4,4'-methylene bis-(phenyl isocyanate), hexamethylene diisocyanate, 3,3'-dimethyldiphenyl-4,4'-diisocyanate, isophenyl diisocyanate, phenylene-1,4-diisocyanate, naphthalene-1,5-diisocyanate, diphenylmethane-3,3'-dimethoxy-4,4'-diisocyanate, toluene diisocyanate, isophorone diisocyanate, 1,4-cyclohexyl diisocyanate, decane-1,10-diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, and mixtures thereof.

12. The composition of claim 11, wherein the diisocyanate comprises or is composed of 4,4'-methylenebis-(phenyl isocyanate).

13. The composition according to any one of the preceding claims, wherein the chain extender is selected from the group consisting of: ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,3-butanediol, 1,5-pentanediol, 1,4-cyclohexanediol, hydroquinone di(hydroxyethyl) ether, neopentyl glycol, 1,4-bis(2-hydroxyethoxy)benzene, and mixtures thereof.

14. The composition of claim 13, wherein the chain extender comprises or is composed of 1,4-butanediol.

15. The composition according to any one of the preceding claims, wherein the imidazolium liquid salt is selected from the group consisting of: 1-methyl-3-octylimidazolium chloride; 1-methyl-3-octylimidazolium bromide; 1-methyl-3-octylimidazolium iodide; 1-methyl-3-octylimidazolium hexafluorophosphate; 1-methyl-3-octylimidazolium tetrafluoroborate; 1-methyl-3-octylimidazolium hexafluoroantimonate; 1-methyl-3-octylimidazolium trifluoromethanesulfonate; 1-methyl-3-octylimidazolium methyl sulfate; 1-methyl-3-octylimidazolium ethyl sulfate; 1-methyl-3-octylimidazolium acetate; 1-methyl-3-octylimidazolium thiocyanate; 1-methyl-3-octylimidazolium dicyandiamide. ; 1-Methyl-3-octylimidazolium bis(trifluoromethanesulfonyl)amide; 1-Butyl-3-methylimidazolium tetrafluoroborate; 1-Octyl-2,3-dimethylimidazolium chloride; 1-Octyl-2,3-dimethylimidazolium bromide; 1-Octyl-2,3-dimethylimidazolium iodide; 1-Octyl-2,3-dimethylimidazolium hexafluorophosphate; 1- Octyl-2,3-dimethylimidazolium tetrafluoroborate; 1-octyl-2,3-dimethylimidazolium hexafluoroantimonate; 1-octyl-2,3-dimethylimidazolium trifluoromethanesulfonate; 1-octyl-2,3-dimethylimidazolium methyl sulfate; 1-octyl-2,3-dimethylimidazolium ethyl sulfate; 1-octyl-2,3-dimethylimidazolium acetate; 1 -Octyl-2,3-dimethylimidazolium thiocyanate; 1-Octyl-2,3-dimethylimidazolium dicyanamide; 1-Octyl-2,3-dimethylimidazolium bis(trifluoromethanesulfonyl)amide; 1-Ethyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide; 1-Decyl-3-methylimidazolium chloride; 1-Decyl-3-methylimidazolium bromide; 1-Decyl-3-methylimidazolium iodide; 1-Decyl-3-methylimidazolium hexafluorophosphate; 1-Decyl-3-methylimidazolium tetrafluoroborate; 1-Decyl-3-methylimidazolium hexafluoroantimonate; 1-Decyl-3-methylimidazolium trifluoromethanesulfonate; 1-Decyl-3-methylimidazolium methyl sulfate; 1-Decyl-3-methylimidazolium ethyl sulfate ; 1-Decyl-3-methylimidazolium acetate; 1-Decyl-3-methylimidazolium thiocyanate; 1-Decyl-3-methylimidazolium dicyanamide; 1-Decyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide; 1-Ethyl-3-methylimidazolium ethyl sulfate; 1-Dodecyl-3-methylimidazolium chloride; 1-Dodecyl-3-methylimidazolium bromide; 1-Dodecyl-3-methylimidazolium iodide; 1-Dodecyl-3-methylimidazolium hexafluorophosphate; 1-Dodecyl-3-methylimidazolium tetrafluoroborate; 1-Dodecyl-3-methylimidazolium hexafluoroantimonate; 1-Dodecyl-3-methylimidazolium trifluoromethanesulfonate; 1-Dodecyl-3-methylimidazolium methyl sulfate;1-Dodecyl-3-methylimidazolium ethyl sulfate; 1-Dodecyl-3-methylimidazolium acetate; 1-Dodecyl-3-methylimidazolium thiocyanate; 1-Dodecyl-3-methylimidazolium dicyanamide; 1-Dodecyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide; 1-Tetradecyl-3-methylimidazolium chloride; 1-Tetradecyl-3-methylimidazolium bromide; 1-Tetradecyl-3-methylimidazolium iodide; 1-Tetradecyl-3-methylimidazolium hexafluorophosphate; 1-Tetradecyl-3-methylimidazolium tetrafluoroborate; 1-Tetradecyl-3-methylimidazolium hexafluoroantimonate; 1-Tetradecyl-3-methylimidazolium trifluoromethanesulfonate; 1-Tetradecyl-3-methylimidazolium methyl sulfate; 1-Tetradecyl-3-methylimidazolium ethyl sulfate; 1-Tetradecyl-3-methylimidazolium acetate; 1-Tetradecyl-3-methylimidazolium thiocyanate Salts; 1-Tetradecyl-3-methylimidazolium dicyandiamide; 1-Tetradecyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide; 1-Hexadecyl-3-methylimidazolium chloride; 1-Hexadecyl-3-methylimidazolium bromide; 1-Hexadecyl-3-methylimidazolium iodide; 1-Hexadecyl-3-methylimidazolium hexafluorophosphate; 1-Hexadecyl-3-methylimidazolium tetrafluoroborate; 1-Hexadecyl-3-methylimidazolium hexafluorophosphate Fluoroantimonates; 1-hexadecyl-3-methylimidazolium trifluoromethanesulfonate; 1-hexadecyl-3-methylimidazolium methyl sulfate; 1-hexadecyl-3-methylimidazolium ethyl sulfate; 1-hexadecyl-3-methylimidazolium acetate; 1-hexadecyl-3-methylimidazolium thiocyanate; 1-hexadecyl-3-methylimidazolium dicyanamide; 1-hexadecyl-3-methylimidazolium bis(trifluoromethanesulfonyl)amide, and mixtures thereof.

16. The composition according to any one of the preceding claims, wherein the imidazodium liquid salt comprises or is composed of 1-ethyl-3-methylimidazodium bis(trifluoromethylsulfonyl)imide.

17. The composition according to any one of claims 1 to 13, wherein the imidazodium liquid salt comprises or is composed of 1-butyl-3-methylimidazodium tetrafluoroborate.

18. The composition according to any one of the preceding claims, wherein the imidazolyl liquid salt is added to the thermoplastic polyurethane in an amount of 0.5 parts / 100 to 25 parts / 100, or 1 part / 100 to 20 parts / 100, or 2 parts / 100 to 16 parts / 100, based on 100 parts of the thermoplastic polyurethane.

19. A molded polymer article comprising the electrostatic dissipation heat-dissipating plastic polyurethane composition according to any one of claims 1 to 18.

20. The polymer article of claim 19, wherein the article is selected from the group consisting of: packaging materials for ESD-sensitive semiconductors and electronic components, durable or consumable components for cleanroom equipment and applications, construction materials for cleanrooms and data centers, fibers, laminated sheets, conveyor belts, pharmaceutical products, medical devices, electronic components, separators for constructing lithium-ion batteries, and polymer electrolyte membranes for constructing lithium polymer batteries and fuel cells.

21. A method for reducing the surface resistivity of a polymer article, the method comprising molding the article using a thermoplastic polyurethane composition according to any one of claims 1 to 17.