Patent Application
20180079986
The present invention is related to improved metal working additives. More specifically, the present invention is related to non-chlorinated alkoxylated alcohol phosphates for metal working.
While chlorinated paraffin (CP) has been a highly effective metal working additive, in terms of cost and performance, for nearly a century their continued use is being limited by the U.S. Environmental Protection Agency (EPA). Beginning in 1985, short-chain CPs were listed in the EPA's toxic release inventory. More recently, medium-chain CPs have come under similar scrutiny and their continued use is likely to be banned in the near future.
Although CPs are cost-effective in use, removal of these medium to high viscosity additives is both difficult and expensive. In addition, used fluids containing these chemistries are classified as hazardous wastes under the U.S. Resource Conservation And Recovery Act (RCRA). CPs are classified as persistent in the environment and thus have a high potential for bioaccumulation.
There is a significant demand for metal working additives which do not contain chlorides. Unfortunately, the activity of such materials has been lacking. An improved metal working additive is provided herein.
The present invention is related an improved metal working additive.
More specifically, the present invention is related to an improved metal working additive which does not contain chloride and is considered less toxic than prior art additives. Phosphate esters, such as those of the present invention, are known to readily biodegrade.
A particular feature of the invention is the ability for removal and disposal of the metal working additive with water.
Another particular feature of the invention is the suitability of the metal working additive in water-based systems or oil-based systems.
These and other embodiments, as will be realized, are provided in an improved metal working composition comprising an additive defined by Formula I:
[R1—(CO)yO(CH2CHR2O)z]nPO4-nX3-n Formula I
wherein:
R1 is a saturated or unsaturated, branched or linear, alkyl or aryl hydrocarbon group comprising at least 10 to no more than 24 carbons;
each R2 is independently selected from H and alkyl of 1-5 carbons;
X is a cation or hydrogen;
y is 0 or 1;
z is an integer of 1 to 20; and
n is 1 or 2.
Yet another embodiment is provided in a method of forming a metal working composition comprising:
alkoxylating an alcohol defined as:
R1OH;
or a carboxylic acid defined as:
R1COOH;
and terminating the alkoxylated alcohol with phosphate thereby providing a compound of Formula I:
[R1—(CO)yO(CH2CHR2O)z]nPO4-nX3-n Formula I
wherein:
R1 is a saturated or unsaturated, branched or linear, alkyl or aryl hydrocarbon group comprising at least 10 to no more than 24 carbons;
each R2 is independently selected from H and alkyl of 1-5 carbons;
X is a cation or hydrogen;
y is 0 or 1;
z is an integer of 1 to 20; and
n is 1 or 2.
Yet another embodiment is provided in a method of working metal comprising:
applying a metal working composition to said metal wherein said metal composition comprises an additive defined by Formula I:
[R1—(CO)yO(CH2CHR2O)z]nPO4-nX3-n Formula I
wherein:
R1 is a saturated or unsaturated, branched or linear, alkyl or aryl hydrocarbon group comprising at least 10 to no more than 24 carbons;
each R2 is independently selected from H and alkyl of 1-5 carbons;
X is a cation or hydrogen;
y is 0 or 1;
z is an integer of 1 to 20; and
n is 1 or 2;
and
stamping, drilling or shaping said metal.
The present invention is related to an improved additive for metal working. More specifically, the present invention is related to a phosphated, alkoxylated medium-long chain alcohol.
The improved additive is defined by Formula I:
[R1—(CO)yO(CH2CHR2O)z]nPO4-nX3-n Formula I
wherein:
R1 is a saturated or unsaturated, branched or linear, alkyl or aryl hydrocarbon group comprising at least 10 to no more than 24 carbons;
each R2 is independently selected from H and alkyl of 1-5 carbons;
X is a cation or hydrogen;
y is 0 or 1;
z is an integer of 1 to 20; and
n is 1 or 2.
The improved additive is formed by alkoxylating an alcohol, defined as R1OH, or carboxylic acid, defined as R1COOH, followed by formation of the terminal phosphate. Alkoxylation is well known to those of skill in the art and further discussion of the reaction conditions to alkoxylate an alcohol or carboxylic acid is not necessary. In Formula I, subscript y being 0 is achieved by alkoxylation of an alcohol and subscript y being 1 is achieved by alkoxylation of a carboxylic acid. It is known in the art that alkoxylation provides a statistical average distribution as opposed to an equal distribution of alkoxy groups on each molecule. Therefore, a representation of the number of alkoxy groups is understood to be the average with a statistical distribution of molecules having more or less alkoxy groups.
Formation of a terminal phosphate after alkoxylation is well known to those of skill in the art and further elaboration of the reaction is not necessary. Formation of the terminal phosphate can be accomplished by reacting with a phosphating agent, such as polyphosphoric acid or by phosphoric pentoxide, under elevated temperature. The formation of the terminal phosphate is known to provide some small fraction of byproducts such as the presence of molecules with two alkoxylated alcohol moieties per phosphoric acid reactant. In an embodiment of the invention, a polyphosphate such as polyphos 115% is used for the phosphation step. This reaction will yield predominantly monosubstituted phosphate products (n=1), with minor amounts of di-substituted phosphate compounds (n=2) as well as some residual phosphoric acid. If phosphoric pentoxide is used, higher yields of the di- and trisubstituted phosphates will be obtained. While these more highly substituted phosphates are a part of this invention, it has been found that in most cases improved results are obtained from monosubstituted phosphate compounds.
Preferably, R1 is an alkyl or alkene group. Particularly preferred R1 are those organic residues of oleyl alcohol, oleic acid, stearic acid, stearyl alcohol, coconut fatty acids, styrenated phenols, or tall oil fatty acids. R1 can be linear or branched with linear being preferred and oleyl being particularly preferred.
R2 is preferably either —H or —CH3. Preferably, each R2 is mixture —H and —CH3. In another preferred embodiment at least one R2 is —CH3. In a particularly preferred embodiment up to ten R2 groups are —CH3 and more preferably 3-7 R2 groups are —CH3. In another preferred embodiment no more than 10 R2 groups are —H and more preferably 1-3 R2 groups are —H. Similar R2 groups can be arranged in blocks or arranged randomly. For example, with a mixture or —H and —CH3 groups as R2 the —H groups may be in a block and the —CH3 groups may be in a block as represented by the moiety:
—(CH2CH2O)a(CH2CHCH3O)b—
wherein the sum of a and b taken together represent integer z. The alkoxylate chains can be obtained by reacting a suitable alcohol or acid with ethylene oxide or propylene oxide. These oxides can be added in a stepwise fashion in order to obtain blocked alkoxylates, or they can be pre-mixed to provide a statistical mixture.
The number of alkoxy groups, represented by integer z, is more preferably at least 4 to no more than 14.
The cation, represented by X, is preferably a cation of a material selected from the group consisting of hydrogen which is a non-neutralized phosphate, sodium, potassium, ammonium, calcium, magnesium, lithium and an amine. Particularly preferred is a hydrogen cation or non-neutralized phosphate. Particularly preferred are cations of aromatic or alkyl amines and alkanol amines with ethanolamine and ethylene amine being particularly preferred.
The improved additive is preferably used in a composition for metal working comprising a base oil. Particularly preferred base oils include mineral oils, vegetable oils and synthetic oils. The improved additive preferably represents about 1 wt % to about 20 wt % with the balance being base oil and additional additives as known in the art. It is preferable that the composition for metal working comprise about 80 wt % to about 99 wt % base oil.
The improved additive has a non-tacky, easy to use, medium viscosity. It is soluble in a wide range of base fluids, including mineral and vegetable oils and esters. It is also compatible with other extreme pressure and lubricity additives, such as esters, sulfurized fats and sulfurized hydrocarbons.
The acid functionality of this invention allows ease of removal using alkaline cleaners. Simple neutralization of this acid with common mineral and organic bases also allow its use in emulsifiable, water-extendable metalworking formulations.
The effect that mixed alkoxylation has on 4-Ball wear performance as compared to purely ethoxylated analogs provides a surprising advantage. While formulations using only ethylene oxide in Formula I are suitable for metal working applications, propylene oxide incorporation provides improved properties. Furthermore, unsaturation in the alcohol chain provides a performance benefit, which is contrary to expectations for lubrication applications. Likewise, the strong 4-ball wear performance of an additive having low-to-medium viscosity is contrary to expectations in the art. The improved additive is particularly suitable for use in combination with other lubricant additives and film strength improvers such as higher viscosity esters, fats, and/or hydrocarbons, extends the use for heavy-duty metal forming applications.
The inventive additive is suitable for use with any metal. The inventive additive is particularly suitable for use in the stamping, drilling and shaping of ferrous and non-ferrous metal. The inventive additive is particularly suitable for use in aluminum, copper, magnesium iron, steel and ferrous alloy.
Oleyl alcohol was reacted with five molar equivalents of propylene oxide, followed by reaction with one and a half moles of ethylene oxide to yield a propoxylated and ethoxylated alcohol. This material was then reacted with 0.33 molar equivalents of PPA 115 polyphosphoric acid to yield Compound 1.
Compound 1 was subjected to a 4-ball wear test according to ASTM D2783-03. Compound 1 was mixed with a paraffinic oil having a Saybolt Universal Second (SUS) viscosity of 100 at 10% by weight and compared to a medium chain chlorinated paraffin also used at 10% by weight. The load wear index and weld load for the medium chain chlorinated paraffin were 41 kgf and 200 kg, respectively, as reported in Table 1. The load wear index and weld load for Compound 1 were above 216 kgf and above 620 kg, respectively as reported in Table 1. This compared favorably to a commercially available chlorinated paraffin replacement with 2.6 wt % phosphorous added.
The procedure for Example 1 was repeated using 5% Compound 1 in paraffinic oil and tested against 5% chlorinated paraffin in paraffin oil. The load wear index and weld load for the medium chain chlorinated paraffin were 57 kgf and 315 kg, respectively. The load wear index and weld load for compound 1 were 77 kgf and above 380 kg, respectively.
To evaluate the impact of structural variations, the above tests were carried out on a version of this material prepared from P2O5 rather than polyphosphoric acid (Compound 2), using saturated stearyl alcohol in place of oleyl alcohol (Compound 3), and using five moles of ethylene oxide in place of an ethylene oxide/propylene oxide mixture (Compound 4). Compounds 2-4 were also shown to be superior to chlorinated paraffins as presented in Table 1.
The invention has been described with reference to the preferred embodiments without limit thereto. Additional embodiments and improvements may be realized which are not specifically set forth herein but which are within the scope of the invention as more specifically set forth in the claims appended hereto.
The present application claims priority to pending U.S. Provisional Appl. No. 62/396,911 filed Sep. 20, 2016, which is incorporated herein by reference
| Number | Date | Country | |
|---|---|---|---|
| 62396911 | Sep 2016 | US |
