Patent Application
20160160071
The present invention relates to functionalized polyolefins suitable as corrosion inhibitors.
Pipe and metal piling corrosion in aqueous or aqueous/hydrocarbon fluids has always been a problem for the oil and gas industry in production and supply pipelines of municipal water and gas/oil. The corrosion is most severe during the oil and gas production as a result of the corrosive and erosive components present in the extracted fluids, such as brines, organic acids, carbon dioxide, hydrogen sulfide, microorganisms, sands and rocks. These aggressive constituents can cause severe corrosion to metal pipes and can be extremely costly and disruptive in deep-sea operations where replacement of corroded equipment is difficult. Therefore it is common practice to employ corrosion inhibitors during the production, transportation, storage, and separation/purification of crude oil and natural gas.
Corrosion inhibitors are usually surface-active compounds that form dynamic coatings on the metal surface to minimize metal surface contacts to corrosive and erosive components and to suppress corrosion. By “dynamic” it is meant that there is an exchange of the corrosion inhibitor between the solution that the metal surface is exposed to and the metal surface. This dynamic exchange necessitates a continuous injection of the corrosion inhibitors into the fluid streams of metal pipes, or treatment of outer pipe/piling surfaces. Thus, it is advantageous for the corrosion inhibitor to bind to the metal surface tightly in order to reduce the rate of exchange.
Present commercial inhibitors are based on the usage of surfactants that have polar heads, most commonly amines, and an alkyl tail, mostly having a carbon number less than 14 to 25 carbons (MW<500 g/mole). These surfactants can help to slow down the corrosion rate by an average reduction rate of 50%. More particularly, common corrosion inhibitors are typically composed of amines, condensation products of fatty acids with polyamines (“PA”), for example, imidazolines, or quaternary ammonium compounds. Among the most frequently used corrosion inhibitors in crude oil and natural gas extraction are imidazoline derivatives. Alternative corrosion inhibitors that can be used alone or in combination with known corrosion inhibitors are being sought by the industry.
In this invention, a polyolefin with a molecular weight of at least 500 g/mole, preferably with a carbon number greater than 14, is used as the building block for the corrosion inhibitor. Most specifically, a vinyl terminated polyolefin is used for the corrosion inhibitor assembly. Raising the alkane carbon numbers requires the redesign of the hydrophilic part from a polar head to blocks of hydrophilic polymers so that the polyolefin block can be dispersed in water. Multiple blocks of hydrophilic, amine-containing, polymers also improve the metal surface affinity and adhesion strength.
Related disclosures include: US 2009/0318644; WO 2009/1555517; WO 2009/155510; WO 2009/1555471; WO 2009/155472; U.S. Pat. No. 8,816,027; US 2013/0197180; WO 2014/052200; WO 2012/134717; U.S. Pat. No. 8,623,974; US 2012/0245293; US 2012/0245300; WO 2012/134716; U.S. Ser. No. 61/704,611, filed on Sep. 24, 2012; U.S. Ser. No. 61/704,725, filed on Sep. 24, 2012; U.S. Ser. No. 61/866,702, filed Aug. 16, 2013; U.S. Ser. No. 61/860,407, filed Jul. 31, 2013; and U.S. Ser. No. 62/068,043, filed Oct. 24, 2014; also, “Hybrid Materials of Different Molecular Architectures,” 39 C
Disclosed herein is a corrosion inhibitor composition comprising the reaction product of a vinyl/vinylidene-terminated polyolefin having within the range from 14 to 2000 carbon atoms and a polyamine having a molecular weight of at least 500 g/mole.
The corrosion inhibitor composition can be formed by the process of reacting the vinyl/vinylidene-terminated polyolefin with a siloxane to form a siloxane functionalized vinyl/vinylidene-terminated polyolefin; reacting the siloxane functionalized vinyl/vinylidene-terminated polyolefin with a allyl-glycol to form a glycol-siloxane vinyl/vinylidene-terminated polyolefin; and reacting the glycol-siloxane vinyl/vinylidene-terminated polyolefin with the polyamine to form the corrosion inhibitor composition.
The corrosion inhibitor composition can also be formed by the process of reacting the vinyl/vinylidene-terminated polyolefin with a hydroformylation agent to form an aldehyde-terminated polyolefin; and reacting the aldehyde-terminated polyolefin with a reducing agent and the polyamine to form the corrosion inhibitor composition.
The invention described herein includes amphiphilic, polyolefin-based corrosion inhibitors and the synthesis of these materials. The corrosion inhibitors described herein are preferably water (at least at 23° C.) soluble, but, when contacted with a metal surface (e.g., steel, iron, copper, etc.), will preferentially bind/adhere or “precipitate” to the metal surface. The amphiphilic polyolefin-based polymer is a block copolymer of one or more polyolefin blocks and one or more hydrophilic polymer blocks, preferably polyamine (“PA”) blocks. The polyolefin block can be a homopolymer or a random copolymer of linear alpha olefins that is amorphous, crystalline or semi-crystalline, with number average molecular weight (number average) preferred to be at least 500 g/mole, and preferably have a carbon number of at least 14, or 18, or 25. Inventive polyolefin-polyamine block copolymer, and in particular embodiments polyolefin-polyalkylimine and polyolefin-poly(glycol)amine block copolymers are described herein for corrosion inhibitor (“CI”) applications were synthesized in the following sequence:
Thus, the invention includes a corrosion inhibitor composition comprising the reaction product of a vinyl/vinylidene-terminated polyolefin having within the range from 14 to 2000 (or any other value disclosed herein) carbon atoms and a polyalkylimine having a molecular weight of at least 500 g/mole (or any other value disclosed herein). The composition may include other reaction products, or consist essentially of (or consist of) the polyolefin-polyamine block copolymer. The composition may also include other additives such as inorganic salts, lower molecular weight surfactants (e.g., less than 400 g/mole) and/or ionic surfactants, solvents, etc., known in the corrosion inhibitor arts. In any embodiment, the vinyl/vinylidene-terminated polyolefin (VTP) is first functionalized before reacting with the polyamine. Preferably, said functionalization converts the vinyl/vinylidene-terminus into an aldehyde, a glycol, and/or a siloxane. By “functionalize” what is meant is that the VTP is reacted with an agent having a desirable functional group such as an oxide or oxygen, or a silane or siloxane that, upon reaction, will form a covalent bond between the agent and the VTP, leaving the functional group intact and chemically available to react with or bind to a substrate, preferably a metal surface.
By “consisting essentially of” what is meant is that the named composition includes only the named block copolymer with less than 3 wt %, or 2 wt %, or 1 wt %, by weight of the composition, of any other component such as a reaction product (e.g., unreacted polyolefin and/or polyamine, reducing agents, reaction catalysts, etc.), but may still include additives as described above. In a particular embodiment, the compositions described and claimed herein “consist” of the named block copolymer, or and includes less than 3 wt %, or 2 wt %, or 1 wt %, or 0.5, or 0.1 wt % of reaction products and additives. Otherwise, reference to “corrosion inhibitor” or “corrosion inhibitor composition” includes minor amounts of reaction products and/or additives as is common in the art.
Thus, the inventive corrosion inhibitor will have a polyolefin block (e.g., polypropylene, polyethylene, or ethylene-propylene copolymer) and a polyamine block (e.g., polyethyleneimine, or poly(glycol)amine), forming a polyolefin-polyamine block copolymer.
The VTPs useful in the inventive functionalized polymers described herein can be made in any number of ways. By “vinyl/vinylidene”, what is meant is that the polyolefin may be a mixture of both vinyl- and vinylidene-terminated polyolefins, or the polyolefin may be substantially all one form or the other. Preferably, the VTP's useful herein are polymers as first described in US 2009/0318644 having at least one terminus (CH2CHCH2-oligomer or polymer) represented by formula (1):
where the “” here represents the “PO” block of the inventive functionalized polyolefins. In a preferred embodiment the allyl chain ends are represented by the formula (2):
The amount of allyl chain ends is determined using 1H NMR at 120° C. using deuterated tetrachloroethane as the solvent on a 500 MHz machine, and in selected cases confirmed by 13C NMR. These groups (1) and (2) will react to form a chemical bond with a metal as mentioned above to form the M-CH2CH2-polymer. In any case, Resconi has reported proton and carbon assignments (neat perdeuterated tetrachloroethane used for proton spectra while a 50:50 mixture of normal and perdeuterated tetrachloroethane was used for carbon spectra; all spectra were recorded at 100° C. on a Bruker AM 300 spectrometer operating at 300 MHz for proton and 75.43 MHz for carbon) for vinyl-terminated propylene polymers in Resconi et al, 114, J. A
The vinyl/vinylidene-terminated propylene-based polymers may also contain an isobutyl chain end. “Isobutyl chain end” is defined to be an oligomer having at least one terminus represented by the formula (3):
In a preferred embodiment, the isobutyl chain end is represented by one of the following formulae (4):
The percentage of isobutyl end groups is determined using 13C NMR (as described in the example section) and the chemical shift assignments in Resconi for 100% propylene oligomers. Preferably, the vinyl/vinylidene-terminated polymers described herein have an allylic terminus, and at the opposite end of the polymer an isobutyl terminus.
The VTPs can be made by any suitable means, but most preferably the VTPs are made using conventional slurry or solution polymerization processes using a combination of bridged metallocene catalyst compounds (especially bridged bis-indenyl or bridged 4-substituted bis-indenyl metallocenes) with a high-molecular volume (at least a total volume of 1000 Å3) perfluorinated boron activator, for example, as described in US 2012/0245299.
The vinyl/vinylidene-terminated polyolefin can be any polyolefin having a vinyl/vinylidene-terminal group, and is preferably selected from the group consisting of vinyl/vinylidene-terminated isotactic polypropylenes, atactic polypropylenes, syndiotactic polypropylenes, propylene-butene copolymers, propylene-hexene copolymers, and propylene-ethylene copolymers (wherein the copolymers may be random, elastomeric, impact and/or block), and combinations thereof, each having a number-average molecular weight (Mn) of at least 300 g/mole. In any embodiments, the VTP may be a copolymer or terpolymer wherein the C2 content (ethylene derived units) of the vinyl/vinylidene-terminated polyolefin is from 3 to 50 wt %, the C3 content (propylene derived units) is from 50 to 97 wt %; in yet another embodiment, the VTP may contain a third comonomer, thus, the C4 through C14 content (units derived from C4 to C14 α-olefins or dienes) is from 5 to 30 wt % in those embodiments, while the C2 content is from 5 to 50 wt % and the C3 content is from 20 to 90 wt %.
In any embodiment, greater than 70, or 80, or 90, or 94, or 96% of the VTP polymer chains comprises terminal vinyl or vinylidene groups; or within the range of from 50, or 60 wt % to 70, or 80, or 90, or 95, or 98 or 99% of the polymer chains. As described above, the vinyl/vinylidene-terminated polyolefins preferably have a number average molecular weight (Mn) value of at least 200, or 500, or 1000, or 5000, or 20,000 g/mole, or within a range from 200, or 600, or 800 g/mole to 1000, or 1400, or 1600, or 1800, or 2000, or 4000, or 6000, or 8000, or 10,000 g/mole. The vinyl/vinylidene-terminated polyolefins preferably have a weight-average molecular weight (Mw) value of at least 500, or 800, or 1000, or 5000, or 20,000 g/mole, or within the range of from 500, or 800, or 1000, or 2000, g/mole to 6,000, or 10,000, or 12,000, or 20,000, or 30,000, or 40,000 or 50,000, or 100,000, or 200,000, or 300,000 g/mole. Preferably, the VTP useful herein is amorphous polypropylene, and desirably has a glass transition temperature (Tg) of less than 10 or 5 or 0° C., more preferably less than −10° C.; or within the range of from 0, or −5, or −10° C. to −30, or −40, or −50° C. or as described herein.
The VTPs are preferably linear, meaning that there is no polymeric or oligomeric branching from the polymer backbone, or described quantitatively, having a branching index “g” (or g′(vis avg)) of at least 0.90 or 0.96 or 0.97 or 0.98, wherein the “branching index” is well known in the art and measurable by published means, and the value of such branching index referred to herein is within 10 or 20% of the value as measured by any common method of measuring the branching index for polyolefins as is known in the art such as in US 2013/0090433.
A particularly preferred VTP is one wherein the vinyl terminated polyolefin is a compound or mixture of compounds represented by the formula (5):
wherein each “R” is selected from hydrogen and C1 to C4 or C10 alkyls, preferably hydrogen or methyl, or a mixture thereof; and n is an integer from 14, or 16, or 18, or 20, or 25, or 50 to 100, or 200, or 500, or 800, or 1000, or 1500, or 2000. In any embodiment, the vinyl/vinylidene-terminated polyolefin is a vinyl/vinylidene-terminated atactic polypropylene or polyethylene, or mixture thereof, meaning that it is an ethylene-propylene copolymer. It is these VTPs that are reacted, under suitable conditions, with a functionalizing agent to form the functionalized polyolefins which can react with the functionalized siloxanes described herein to form siloxane functionalized polyolefins.
The “polyamine” (“PA”) as used herein is a polymeric amine (or, “imine”) having multiple amine and/or imine groups. Useful PAs can be represented by the formula: (R—NH)x, where “R—NH” is a polymeric or monomeric unit where “R” contains from 1 to 4, or 6, or 10, or 20 carbon atoms; “x” is an integer from 1 to 50, or 100, or 200, or 500 or 100,000. In any embodiment, the number average molecular weight (Mn) of the polyamine is within a range from 500, or 1000 g/mole to 800, or 1000, or 1200, or 1600, or 2000, or 2200, or 2600, or 3000 g/mole. The polyalkyleneimine may comprise one or more ether or glycol groups as well, and most preferably, as at least one terminal amine group, preferably each end of the polymer chains is a terminal amine.
More particularly, the PA is a “polyalkylimine” (PAI) and may be represented by the following general formula: (—NHCH2CH2—)m[—N(CH2CH2NH2)CH2CH2—], wherein m is from 10, or 20, or 50 to 200, or 500, or 1,000, or 10,000, or 20,000, and n is from 10, or 20, or 50 to 200, or 500, or 1,000, or 10,000, or 20,000. Useful PAIs may also comprise secondary amines and/or tertiary amines, such as represented in (—NRCH2CH2—)m[—N(CH2CH2NR2)CH2CH2—], wherein each “R” is independently a C1 to C10, or C20 alkyl, alkylamine, aryl, or arylamine. The PAIs preferably have a level of secondary amines within the range of from 20 or 30 or 40% to 60 or 70 or 80% relative to all the nitrogens on the PAI. Also, the PAIs preferably have, independently, a level of primary and tertiary amines within the range of from 5 or 10 or 15% to 30 or 35 or 40 or 50% relative to all the nitrogens on the PAI.
In any embodiment, the PAIs that are useful herein have a weight average molecular weight (Mw) of from 400, or 500, or 600, or 800 or 1,000 g/mole to 10,000 or 20,000 or 30,000 or 50,000 g/mole. In any embodiment, the number average molecular weight (Mn) of the polyalkylimine is within a range from 500, or 1000 g/mole to 800, or 1000, or 1200, or 1600, or 2000, or 2200, or 2600, or 3000 g/mole. Examples of desirable commercial PAIs include those sold by Sigma-Aldrich™, or Lupasol™ FG, G20, G35, G100, HF, and P from BASF, and Epomin™ SP012, SP018, SP200, and P1050 from Nippon Shokubai.
In any embodiment, the polyalkylimine is a polyalkylimine having the following general structure (6):
wherein n has a value within the range from 2, or 6, or 10, to 20, or 40, or 60; and wherein the branching depicted in the structure can vary such that the value of a, b, and c can independently be within a range of from 0, or 1, or 2, or 4, to 5 or 10.
In any embodiment, the polyamine also comprises glycol subgroups in the backbone and/or side chains (poly(glycol)amine). More particularly, the polyamine may have the following general structure (7):
wherein the values of x, y, and z can be, independently within a range of from 2, or 4, or 6, or 10, or 20 to 30, or 40, or 50, or 60, and wherein each R is, independently, selected from hydrogen and C1 to C10 alkyls, or C6 to C20 aryls or alkylaryls.
The corrosion inhibitors can be formed by any chemical reaction that will couple the VTP block to a siloxane block. In any embodiment, the corrosion inhibitor is formed by the process of first reacting the vinyl/vinylidene-terminated polyolefin with a siloxane to form a siloxane functionalized vinyl/vinylidene-terminated polyolefin. With or without isolating and/or purifying the first reaction product, the siloxane functionalized vinyl/vinylidene-terminated polyolefin is reacted with an allyl-glycol to form a glycol-siloxane vinyl/vinylidene-terminated polyolefin. Finally, the glycol-siloxane vinyl/vinylidene-terminated polyolefin is reacted with the polyamine such as a polyalkylimine to form the corrosion inhibitor composition (polyolefin-siloxane-polyamine block copolymers, or simply “polyolefin-polyamine block copolymer”). By “reacted with” or “reacting” what is meant is that the components that will form the desired end product are combined together as a liquid or in a desirable solvent at a desirable temperature, and optionally, with catalysts or promoters that facilitate the formation of the desired end product.
Other types of reactions can also be used to form the inventive corrosion inhibitor composition. In any embodiment, a vinyl/vinylidene-terminated polyolefin is reacted with a hydroformylation agent to form an aldehyde-terminated polyolefin. Then, with or without isolating and/or purifying the product, the aldehyde-terminated polyolefin is reacted with a reducing agent and the polyamine such as a polyalkylimine to form the corrosion inhibitor composition. Examples of a suitable reducing agents include lithium aluminum hydride, boron hydride compounds, atomic hydrogen, oxalic acid, diisobutylaluminum hydride, diborane, sodium amalgam, and other electron donating chemical compounds capable of facilitating the desired reaction.
In any case, the inventive corrosion inhibitor will have a polyolefin block (e.g., polypropylene, polyethylene, or ethylene-propylene copolymer) and a polyamine block(s), forming a block copolymer. In any preferred embodiment, the inventive corrosion inhibitor composition is a reaction product having a 1:1, or 2:1, or 3:1, or 4:1 molar ratio of the polyolefin block and the polyamine block, the polyolefin block having a number average molecular weight (Mn) within the range from 500 g/mole to 1000 g/mole. In any preferred embodiment, the corrosion inhibitor has an overall carbon number of greater than 25, or 30, or 40, or 100; or within a range from 25, or 30 to 500, or 800, or 1000 carbons.
The corrosion inhibitor will have in any embodiment a high affinity for polar surfaces, especially metal (iron, aluminum, nickel, etc.) surfaces. This can be determined by any number of means, but in one embodiment, weight loss from a steel surface due to corrosion (reaction and/or loss to the surrounding medium of iron, typically in the form of iron oxide, from the metal surface being tested) by acidic solution and carbon dioxide is a desirable indicator of a corrosion inhibitor's affinity for metal surfaces, and the inventive corrosion inhibitor in any embodiment herein will have a weight loss of less than 3.5 or 3.0 or 2.5 wt % a week, meaning that, by weight, only that percentage of the corrosion inhibitor will detach from the metal surface. This makes the inventive corrosion inhibitors highly desirable as a pipe coating, on its inside, outside, or both surfaces. It can also be used on other surfaces, especially metal surfaces that are exposed to the elements, such as metal pilings, ship hulls, etc., and those surfaces can comprise any type of metal such as iron, steel, zinc, nickel, copper, aluminum, and combinations thereof as is known in the art.
The various descriptive elements and numerical ranges disclosed herein for the inventive corrosion inhibitor composition and methods of forming such can be combined with other descriptive elements and numerical ranges to describe the invention(s); further, for a given element, any upper numerical limit can be combined with any lower numerical limit described herein, including the examples. The features of the inventions are demonstrated in the following non-limiting examples.
Polyolefin-polyetheramine and polyolefin-polyamine block copolymers for corrosion inhibitor (“CI”) applications were synthesized in the following general sequence:
Polymer molecular weight (weight-average molecular weight, Mw number-average molecular weight, Mn and z-averaged molecular weight, Mz), and molecular weight distribution (Mw/Mn) were determined using Size-Exclusion Chromatography (“GPC”). Equipment consists of a High Temperature Size Exclusion Chromatograph (either from Waters Corporation or Polymer Laboratories), with a differential refractive index detector (DRI), an online light scattering detector, and a viscometer (SEC-DRI-LS-VIS). For purposes of the claims, SEC-DRI-LS-VIS shall be used. Three Polymer Laboratories PLgel 10 mm Mixed-B columns are used. The nominal flow rate is 0.5 cm3/min and the nominal injection volume is 300 μL. The various transfer lines, columns and differential refractometer (the DRI detector) are contained in an oven maintained at 135° C. Solvent for the SEC experiment is prepared by dissolving 6 grams of butylated hydroxy toluene as an antioxidant in 4 liters of reagent grade 1,2,4-trichlorobenzene (TCB). The TCB mixture is then filtered through a 0.7 μm glass pre-filter and subsequently through a 0.1 μm Teflon filter. The TCB is then degassed with an online degasser before entering the SEC.
Polymer solutions are prepared by placing dry polymer in a glass container, adding the desired amount of TCB, then heating the mixture at 160° C. with continuous agitation for about 2 hours. All quantities are measured gravimetrically. The TCB densities used to express the polymer concentration in mass/volume units are 1.463 g/ml at room temperature and 1.324 g/ml at 135° C. The injection concentration can range from 1.0 to 2.0 mg/ml, with lower concentrations being used for higher molecular weight samples.
A round-bottomed flask was charged with tetrakis(dimethylsiloxy)silane (TDMS, 1.5 grams, 4.56 millimoles) and toluene (10 milliliters). The mixture was stirred under nitrogen at ambient temperature. Vinyl-terminated atactic polypropylene (1.5 grams, Mn 978 g/mole, 1.63 millimoles) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex were dissolved in toluene (40 milliliters) and the solution was transferred into an addition funnel, then dropwise added into the round-bottomed flask. After the addition was complete, the mixture was stirred for another 2 hours, after which 1H NMR showed that the vinyl was gone. Allyl glycidyl ether (6 grams, 52.6 millimoles) was then added. Platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex was replenished. The reaction mixture was stirred for 2 hours, after which 1H NMR showed that the Si—H was not present (CDCl3, 25° C.). The reaction mixture was slowly poured into pre-chilled methanol with stirring, the liquid phase was decanted, and the product aPP-epoxide was dried under vacuum.
A round-bottomed flask was charged with Jeffamine™ ED-2003 (approx. Mw 2000 g/mole, poly(ethylene oxide-co-propylene oxide)diamine) and xylene (10 milliliters). The Jeffamine used here has the following structure, where y is an average value of 39, and x+z is an average value of 6:
The mixture was stirred under nitrogen at 110° C. Atactic PP-epoxide (0.7 gram, 0.51 millimoles) was dissolved in xylene (40 milliliters) and the solution was transferred into an addition funnel, then dropwise added into the round-bottomed flask. After the addition was complete, the mixture was stirred at 110° C. overnight, after which the solvent was removed under vacuum. 1H NMR of aPP-polyetheramine copolymer (CDCl3, 25° C.) confirmed the product. The Scheme (1) below shows the synthesis of aPP-polyetheramine copolymer (Example 1):
A round-bottomed flask was charged with tetrakis(dimethylsiloxy)silane (TMDS, 1.5 grams, 4.56 millimoles) and toluene (10 milliliters). The mixture was stirred under nitrogen at ambient temperature. Vinyl-terminated aPP (1.2 grams, Mn 908 g/mole, 1.32 millimoles) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex were dissolved in toluene (40 milliliters) and the solution was transferred into an addition funnel, then dropwise added into the round-bottomed flask. After the addition was complete, the mixture was stirred for overnight. Allyl glycidyl ether (6 grams, 52.6 millimoles) was then added. Platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex was replenished. The reaction mixture was stirred for 4 hours, after which 1H NMR showed that the Si—H was gone. The reaction mixture was slowly poured into pre-chilled methanol with stirring, the liquid phase was decanted, and the product was dried under vacuum. 1H NMR of aPP-epoxide (CDCl3, 25° C.) confirmed the product.
A round-bottomed flask was charged with polyethyleneimine (branched, Mn about 600 g/mole, 2.69 grams) and chloroform (10 milliliters). The mixture was stirred under nitrogen at ambient temperature. Atactic PP-epoxide (0.76 gram) was dissolved in chloroform (40 milliliters) and the solution was transferred into an addition funnel, then dropwise added into the round-bottomed flask. After the addition was complete over 3 days, the solvent was removed under vacuum. 1H NMR of aPP-polyethyleneimine copolymer (CDCl3, 25° C.) confirmed the product, as shown in
A round-bottomed flask was charged with tetrakis(dimethylsiloxy)silane (0.8 gram, 2.43 millimoles) and xylene (10 milliliters). The mixture was stirred under nitrogen at ambient temperature. Vinyl-terminated aPP (2.0 grams, Mn 908 g/mole, 2.20 millimoles) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex were dissolved in xylene (50 milliliters) and the solution was transferred into an addition funnel, then dropwise added into the round-bottomed flask. After the addition was complete, the mixture was heated to 50° C. for 2 hours. Allyl glycidyl ether (0.82 gram, 7.18 millimoles) was then added. Platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex was replenished. The reaction mixture was stirred for 2 hours, after which the reaction mixture was transferred into an addition funnel. A second flask was charged with polyethyleneimine (branched, Mn about 600 g/mole, 4.3 grams) and chlorobenzene (10 milliliters). The mixture was stirred under nitrogen and heated to reflux (132° C.). The reaction mixture in the addition funnel was then added to the second flask dropwise. When the addition was complete, the reaction mixture was maintained at reflux for overnight, after which the solvent was distilled out and final product was dried under vacuum.
A round-bottomed flask was charged with tetrakis(dimethylsiloxy)silane (1.0 grams, 3.04 millimoles) and xylene (10 milliliters). The mixture was stirred under nitrogen at ambient temperature. Vinyl-terminated aPP (1.0 gram, Mn 2077 g/mole, 0.48 millimoles) and platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex were dissolved in xylene (30 milliliters) and the solution was transferred into an addition funnel, then dropwise added into the round-bottomed flask. After the addition was complete, the mixture was heated to 50° C. for 2 hours. Allyl glycidyl ether (1.8 grams, 15.8 millimoles) was then added. Platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex was replenished. The reaction mixture was stirred for 2 hours, after which heat was removed and the reaction mixture was slowly added to pre-chilled methanol (300 milliliters) with stirring. The solid was isolated by centrifuging and dried under vacuum. 1H NMR (CDCl3, 25° C.) showed that all vinyl was consumed and glycidyl ether was attached to aPP. There was still some unreacted Si—H.
The above product was dissolved in chlorobenzene (30 milliliters) and the solution was transferred to an addition funnel. A round-bottomed flask was charged with polyethyleneimine (branched, avg. Mn (GPC) of 600 g/mole, 1.0 gram) and chlorobenzene (20 milliliters). The mixture was stirred under nitrogen and heated to reflux (132° C.). The solution in the addition funnel was then added to the flask dropwise. When the addition was complete, the reaction mixture was maintained at reflux for overnight, after which the solvent was distilled out and final product was dried under vacuum.
A bottle was charged with vinyl polyethylene (1.0 gram, 0.728 millimole), platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex and xylene (80 milliliters) and was then sealed and sonicated for 99 minutes, generating a slurry, which was transferred to an addition funnel. A round-bottomed flask was charged with tetrakis(dimethylsiloxy)silane (1.0 grams, 3.04 millimoles) and xylene (40 milliliters). The solution was heated to 110° C. under nitrogen with stirring. The mixture was stirred under nitrogen at 110° C. The slurry in the addition funnel was then added to the flask dropwise. After the addition was complete, the reaction mixture was maintained at 110° C. for 2 hours. Allyl glycidyl ether (2.4 grams, 21.0 millimoles) was added. Platinum(0)-1,3-divinyl-1,1,3,3-tetramethyldisiloxane complex was replenished. The mixture was maintained at 110° C. for 2 hours. The solvent was removed by vacuum distillation. Pentane (100 milliliters) was added to the solid and stirred for 30 minutes. Then the mixture was filtered and the solid was collected and dried under vacuum. 1H NMR (CDCl2CDCl2, 110° C.) showed that vinyl and Si—H were gone and glycidyl ether was attached to PE.
The above product was mixed with xylene (80 milliliters) in a bottle and the mixture was sonicated for 60 minutes. The resulting slurry was transferred to an addition funnel. A round-bottomed flask was charged with polyethyleneimine (branched, avg. Mn (GPC) of 600 g/mole, 1.0 grams, 1.67 millimoles) and chlorobenzene (40 milliliters) and the mixture was heated to reflux (132° C.) under nitrogen with stirring. The slurry in the addition funnel was then added to the flask dropwise. After the addition was complete, the reaction mixture was maintained at reflux for overnight. The solvents were distilled out, and the solid was washed with hexanes and dried under vacuum. The Scheme (3) below shows the synthesis of PE-polyethyleneimine copolymer (example 5):
Three pre-weighed steel coupons were secured to a glass rod by three O-rings as shown in
Conditioned water was prepared by first adjusting the pH of deionized water using sulfuric acid until pH reaches 5, then 100 ppm NaCl were added. Corrosion inhibitor was subsequently added to the conditioned water and agitated vigorously to form a homogeneous solution. The solution was then filled into the flask to the brim. Air was blown into the flask. The flask was maintained at certain temperature for 14 days, after which the steel coupons were removed from the glass rod, cleaned and dried, and weighed individually using the following procedure:
The weight loss on each steel coupon is the weight loss due to corrosion. Greater than 50% reduction in weight loss is demonstrated for all except for the aPP-polyetheramine. These results are shown in Table 1. Note that Example 4 was not tested.
To a round bottom flask containing atactic polypropylene with an aldehyde end-group (2 g, 2.70 mmol) was added THF (15 mL) and PEI (CAS#25987-06-8, avg. Mn (GPC) of 600 g/mole, 1.62 g, 2.70 mmol, very viscous oil, will solidify in THF at approximately 22° C.). The reaction mixture was refluxed at 105° C. under N2 atmosphere for 3 hours Imine formation/incorporation was confirmed by NMR (400 MHz). The reaction mixture exhibited no color change. It was allowed to reach room temperature (approximately 22° C.) and was treated with methanol (5 mL, turned cloudy), followed by addition of NaBH4 (Mw: 37.83 g/mole, 166.45 mg, 4.40 mmol) in 5 portions. The resulting homogeneous solution was stirred at room temperature for 2 hours. The solvents were removed to afford a colorless, viscous oil which was further dried under 50° C. vacuum oven (theoretical yield 3.62 g, 2.70 mmol). Scheme (4) shows the reaction:
To a round bottom flask containing atactic polypropylene with an aldehyde end-group (3.6 g, 4.86 mmol) was added THF (35 mL) and PEI (avg. Mn (GPC) of 600 g/mole, 1.46 g, 2.43 mmol, very viscous oil, will solidify in THF at approximately 22° C.). The reaction mixture was refluxed at 105° C. under N2 atmosphere for 3 hrs Imine formation/incorporation was confirmed by NMR (400 MHz). The reaction mixture exhibited no color change. It was allowed to reach room temperature (approximately 22° C.) and was treated with methanol (10 mL, turned cloudy), followed by addition of NaBH4 (Mw: 37.83 g/mole, 340 mg, 9 mmol) in 5 portions. The resulting homogeneous solution was stirred at room temperature for 2 hours. The solvents were removed to afford a colorless, viscous oil which was further dried under 50° C. vacuum oven (theoretical yield 4.97 g, 2.43 mmol). Scheme (5) shows this reaction:
To a round bottom flask containing atactic polypropylene with an aldehyde end-group (1.20 g, 0.91 mmol) was added THF (35 mL) and PEI (avg. Mn (GPC) of 600 g/mole, 546 mg, 0.91 mmol, very viscous oil, will solidify in THF at approximately 22° C.). The reaction mixture was refluxed at 105° C. under N2 atmosphere for 3 hrs. The imine formation/incorporation was confirmed by NMR (400 MHz). The reaction mixture exhibited no color change. It was cooled to room temperature (approximately 22° C.) and was treated with methanol (2 mL, turned cloudy), followed by addition of NaBH4 (Mw: 37.83 g/mole, 56.75 mg, 1.5 mmol) in 5 portions. The reaction mixture was stirred at approximately 22° C. for 2 hours. The solvents were removed to afford a colorless, viscous oil which was further dried under 50° C. vacuum oven (theoretical yield 2.26 g, 0.91 mmol).
Adapted from 61(11) J. Org. Chem. (1996): The reaction vessel system was purged with N2 for 1 min. While purging with N2, to the 100 mL round bottom flask was added PEI (avg. Mn (GPC) of 600 g/mole, 1.87 g, 3.12 mmol), Octadecanal (C18) (CAS#638-66-4, molecular mass of 268.5 g/mole, 836 mg, 3.12 mmol) and THF (20 mL). After addition, N2 was turned off but the adaptor was still connected to the condenser without security clip to keep the system under N2 atmosphere throughout the experiment and release pressure if necessary. Reaction mixture was refluxed at 105° C. (heating metal temperature, otherwise not collecting) for 3 hrs. NMR (1H, 400 MHz) confirmed reaction completion. The reaction mixture was run almost until colorless and cooled to room temperature. To the mixture was added methanol (5 mL) and NaBH4 (Mw: 37.83 g/mole, 340 mg, 9.00 mmol) in portions. Bubbles formed every time NaBH4 was added. After NaBH4 was all consumed and bubbles were all gone, it was stirred at room temperature for 1 hour to afford an oil, which was further dried under vacuum. Scheme (6) shows this reaction:
A stir bar containing the sample was introduced into the three-neck flask as in
Clarke Solution Application:
The coupons were removed from the testing apparatus to assess their final weight. The coupons were washed with distilled water. The coupon were then placed in the Clarke solution and stirred for one minute. The coupons were then taken out of the Clarke solution and placed in a beaker filled with distilled water. The coupons were then placed in a jar with acetone and blown dry with N2, and finally heated under N2 at 50° C. for 30 minutes. (The acetone was used to help facilitate the drying of the coupon.) The coupons were then weighed.
No CI: Test without any corrosion inhibitor added to the acidified brine solution
PEI: polyethyleneimine, Mn=600 g/mole
741aPP-PEI: atactic polypropylene (Mn=741 g/mole) linked to PEI in 1:1 ratio
C18-PEI: CH3(CH2)17-PEI
(741aPP)2-PEI: atactic polypropylene (Mn=741 g/mole) linked to PEI in 2:1 ratio
1316aPP-PEI: atactic polypropylene (Mn=1316 g/mole) linked to PEI in 1:1 ratio
EC1304A: Commercial corrosion inhibitor from Nalco
Having described the various features of the inventive corrosion inhibitors (polyolefin-siloxane-polyamine block copolymers, or simply “polyolefin-polyamine block copolymers”), described here in numbered paragraphs is:
P1. A corrosion inhibitor composition comprising (or consisting essentially of, or consisting of) the reaction product of a vinyl/vinylidene-terminated polyolefin having a carbon number of at least 14 or 18 or 25, or more preferably within the range from 14, or 16, or 18, or 20, or 25, or 50 to 100, or 200, or 500, or 800, or 1000, or 1500, or 2000 carbon atoms, and a polyamine having a molecular weight of at least 500, or 800, or 1000, or 5000, or 20,000 g/mole.
P2. The corrosion inhibitor composition of numbered paragraph 1 (e.g., P1, P2, etc.), wherein the vinyl/vinylidene-terminated polyolefin is first functionalized before reacting with the polyamine.
P3. The corrosion inhibitor composition of numbered paragraph 2, wherein the functionalization converts the vinyl/vinylidene-terminus into an aldehyde, a glycol, and/or a siloxane.
P4. The corrosion inhibitor composition of any one of the previous numbered paragraphs, wherein the number average molecular weight (Mn) of the polyamine is within a range from 500, or 1000 g/mole to 800, or 1000, or 1200, or 1600, or 2000, or 2200, or 2600, or 3000 g/mole.
P5. The corrosion inhibitor composition of any one of the previous numbered paragraphs, wherein the number average molecular weight (Mn) of the vinyl/vinylidene-terminated polyolefin is within a range from 200, or 600, or 800 g/mole to 1000, or 1400, or 1600, or 1800, or 2000, or 4000, or 6000, or 8000, or 10,000 g/mole.
P6. The corrosion inhibitor composition of any one of the previous numbered paragraphs, wherein the vinyl/vinylidene-terminated polyolefin is a vinyl/vinylidene-terminated atactic polypropylene or polyethylene, or mixture thereof.
P7. The corrosion inhibitor composition of any one of the previous numbered paragraphs, wherein the polyamine also comprises glycol subgroups in the backbone and/or side chains.
P8. The corrosion inhibitor composition of numbered paragraph 7, wherein the polyamine has the following general structure:
Also disclosed is the use of the corrosion inhibitor of any one of the previous numbered paragraphs as a coating on (and/or in) pipes, hulls, and pilings.
Also disclosed is the use of a polyamine-siloxane-polyolefin block copolymer as described above as a corrosion inhibitor.
For all jurisdictions in which the doctrine of “incorporation by reference” applies, all of the test methods, patent publications, patents and reference articles are hereby incorporated by reference either in their entirety or for the relevant portion for which they are referenced.
This invention claims priority to, and the benefit of, U.S. Ser. No. 62/087,377, filed Dec. 4, 2014; also, the present application is related to U.S. Ser. No. 62/154,340 filed Apr. 29, 2015 (Docket No. 2015EM090).
| Number | Date | Country | |
|---|---|---|---|
| 62087377 | Dec 2014 | US | |
| 62154340 | Apr 2015 | US |
