USOO5858244A United States Patent (19) 11 Patent Number: 5,858,244 Tang et al. (45) Date of Patent: Jan. 12, 1999

54 USE OF BIODEGRADABLE POLYMERS IN 4,868,287 9/1989 Sikes et al.. PREVENTION SCALE BUILD-UP 4,906,383 3/1990 Chen et al...... 210/697 5,041,291 8/1991 Bader et al...... 424/426 75 Inventors: Jiansheng Tang, Naperville; Ronald V. 5,051,401 9/1991 Sikes. Davis, Geneva, both of Ill. 5,116,513 5/1992 Koskan et al. . 5,247,068 9/1993 Donachy et al.. 73 Assignee: Nalco Chemical Company, Naperville, 5,284.9365,260,272 11/19932/1994 Donachy et al.. III. 5,328,690 7/1994 Sikes. 5,496,914 3/1996 Wood et al...... 528/328 21 Appl. No.: 944,281 5,506,335 4/1996 Uhr et al...... 528/322 5,527,863 6/1996 Wood et al...... 525/432 22 Filed: Oct. 6, 1997 5,658,464 8/1997 Hann et al...... 210/697 5,776,875 7/1998 Tang et al...... 510/247 Related U.S. Application Data Primary Examiner Peter A. Hruskoci 62) Division of Ser. No. 683,001, Jul 16, 1996, Pat. No. Attorney, Agent, Or Firm Hill & Simpson 5,776.875. 57 ABSTRACT (51)52 U.S.Int. Cl.Cl...... 210,698. 252/180: CO2F5/12 210,700 Albiodegradable scale inhibitor- - - - - and dispersant is provided. 58 Field of Search ...... 210/698-701; The scale inhibitor includes a copolymer comprising at least 252/180, 181,510/24. one of N-oxygenated hydrocarbonamide monomers and at s s least one of amino acid monomers. A method of reducing 56) References Cited Scale build-up on heating eXchanger Surfaces that come in contact with an industrial water is provided by adding a U.S. PATENT DOCUMENTS copolymer comprising at least one of 4,534,881 8/1985 Sikes et all N-oxygenated hydrocarbonamide monomers and at least one 4,585,560 4/1986 Sikes et al. of amino acid monomers to the water System Such as cooling 4,587,021 5/1986 Wheeler et al.. to WerS. 4,603,006 7/1986 Sikes et al.. 4.866,161 9/1989 Sikes et al.. 7 Claims, No Drawings 5,858,244 1 2 USE OF BIODEGRADABLE POLYMERS IN Scales in alkaline Solutions or in the presence of other PREVENTION SCALE BUILD-UP precipitating anions Such as phosphate. Finally, clay particulates may be introduced into an aque This is a division of application Ser. No. 08/683,001, ouS System by the presence of clay in the feedwater. Accu filed Jul 16, 1996 now U.S. Pat. No. 5,776,875. mulation of clay particulates tends to form deposits on metallic heat eXchangers or metal Surfaces of boilers. BACKGROUND OF THE INVENTION The aforementioned Scales and deposits reduce heat transfer, accelerate corrosion or cause other problems result The present invention relates generally to the protection ing in reduced System efficiencies. of metallic Surfaces from Scaling and the accumulation of Currently, certain polyacrylates and polyacrylamides are other deposits. More Specifically, the present invention used to inhibit the build-up of Scales in aqueous Systems. relates to Scale inhibiting compositions, dispersants and However, polyacrylates and polyacrylamides are not biode methods of using the Same. gradable and thus accumulate in the environment upon To efficiently transfer heat from a metal Surface, Such as release from the water treatment Systems. Thus, there is need the inside Surface of a boiler or heat eXchanger tube, to any 15 for biodegradable compositions that are capable of inhibit liquid medium Such as water, or Vice versa, the Surface of the ing the build-up of Scales and deposits on metallic Surfaces. metal should be as clean and as free of Scales and deposits Although polyaspartic acid is biodegradable, it does not as possible. Simply put, Scaling and other deposits on the effectively inhibit the build-up or scales and deposits on metal Surface will reduce the rate of heat transfer between metallic Surfaces. the metal Surface and the water or other fluid medium and SUMMARY OF THE INVENTION therefore Scaling and deposits will reduce the efficiency of the System. Further, Scaling and deposits can lead to pre The present invention provides a family of compositions mature corrosion of metallic Surfaces. that reduce or inhibit development and build-up of scales and deposits on metallic Surfaces and a method of reducing The most common way to combat Scaling and deposit development and build-up of Scales and deposits on metallic accumulation in aqueous Systems is to add Scale-inhibiting 25 surfaces. The family of compositions provided by the additives and dispersants to the feedwater or Solution. present invention includes copolymers comprising at least However, currently available scale-inhibiting additives and one of N-oxygenatedhydrocarbonamides and at least one of dispersants are non-biodegradable, which limits the appli amino acids. cability of such additives. The Scale inhibiting compositions of the present invention Scaling and deposits in industrial heat eXchange Systems comprise copolymers comprising at least one may come in a variety of forms and originate from a variety N-oxygenated hydrocarbonamide or its Salt of the general of Sources. Typically, Scales and deposits are caused by formulas I-C. and I-B as shown below with at least one amino calcium ions, magnesium ions, iron ions, Zinc ions and clay acid compound having the general formula (II) as shown particulates. below. More Specifically, Said Scales and deposits include but are 35 The N-oxygenatedhydrocarbonamide or salt thereof of not limited to alkaline earth metal phosphates, alkaline earth the general formulas I-C. and I-B are as follows: metal carbonates, alkaline earth metal Sulfates, iron (hydro) oxides, Zinc hydroxides, manganese oxides, aluminum (OY), (hydro)oxides, clays and Silicates. O y For example, industrial water, Such as the water used in 40 cooling towers, heat eXchangers and boilers, is often treated HN - OM HN 1. R1N with a variety of inorganic and organic phosphorus (CH2), (CH2), containing compounds. These compounds tend to produce coR COM calcium phosphate and magnesium phosphate Scales which 45 adhere to cooling tower Surfaces, heat eXchanger tubes, and X Y(OY). I-B boiler Surfaces. I-C. Further, Soluble iron may be introduced into an aqueous System by its presence in the feedwater or in other ways. or a mixture of forms I-C. and I-8 in ratios ranging from 1:99 Soluble iron is generally believed to be iron in the form of 50 to 99:1 and wherein M may be hydrogen, a metal, an alkali Fe". Soluble iron, as this term is used herein, does not metalion, an alkaline earth metal ion or NH, Al", Fe", exclude, however, other forms of iron that are Soluble in a Fe", Zn' or mixtures thereof, m ranges from 1 to 10; n may given water System. In acqueous Systems, and particularly be 1 or 2; R may be hydrogen, a C to Cao alkyl group or industrial aqueous water Systems, the presence of Soluble an aryl group or an alkyl or aryl group that is Substituted with iron in the feedwater, or the introduction of a Soluble iron 55 one or more of OH, SOM (wherein M is H or a metal), Species into the System by other means Such as corrosion, POM (wherein M is H or a metal), COM (wherein M is can lead to the undesirable precipitation of iron oxides and OH, OR, or NR wherein R is an alkyl of 3 to 4 carbon iron hydroxides which may settle and accumulate as depos atoms); X may be a C to Co alkylene or arylene; Y may be its on Surfaces that come in contact with the water. Such H, a C, to C alkyl, SOM' or a mixture thereof wherein M' precipitates commonly occur where water containing 60 is a H or a metal ion. Soluble iron ions is changed to a more oxidation-prone Further, X may be a Straight or branched-chain alkylene environment. Also, precipitation will occur where an oxi group having one to thirty carbon atoms or a Straight or dizing agent Such as Oxygen, chlorine and the like is branched-chain alkylene or arylene group Substituted with introduced or increased. one or more of the following: OH, SOM' (wherein M' is Further, many industrial water Systems. Such as those used 65 H or metal), POM (wherein M is H or metal), COM in the operation of cooling towers are treated with Soluble (wherein M is OH, OR, or NR wherein R is an alkyl of 3 Zinc Salts. Such Soluble Zinc Salts tend to form undesired to 4 carbon atoms). 5,858,244 3 4 Still further, X(OY), may be —CHRCH(OCHRCH) (OCHCH)OR' or -CH-CH(NRCHCHR), OR O where R is H or CH or mixtures thereof; oranges from Zero to 50; p ranges from Zero to 50, o-p ranges from 1 to N 50; r ranges from zero to 50; R is a C, to C alkyl group; H R is a C, to C alkyl group; R may be H, CH or SOM where M may be H, alkaline metal ions or N(R), where R' COM is H, a benzyl group or a C to C alkyl group. molar unit of aspartic acid (II), C-form The amino acid compound having the general formula (II) COM is as follows: 1O

O (II) NH HN - OM O R3 15 molar unit of aspartic acid (II), f-form wherein R is a radical defined by the list of amino acids and amino acid derivatives appearing below. If formula (II) is All D, L and DL-optical sources of formula I and II aspartic acid, the aspartic acid unit in the copolymer is in its monomers can be utilized. C. form or B form or a mixture form of C.: B ranging from 99:1 The molecular weight of the polymers of the present to 1:99. invention can vary from about 500 to about 200,000. A preferred molecular weight range is from 500 to 80,000; a The amino acids of the general formula (II) (wherein M more preferred molecular weight range is from 500 to is H, a metal, alkaline metal ions, alkaline earth metal ions, 40,000. NH, Al", Fe', Fe" or mixtures thereof) include alanine, The copolymers of the present invention are biodegrad arginine, aspartic acid, asparagine, cysteine, glutamine, able and extremely effective scale inhibitors of alkaline earth glutamic acid, glycine, histidine, isoleucine, leucine, lysine, 25 metal phosphates Such as calcium phosphate and magnesium methionine, Serine, threonine, tryptophan, tyrosine, Valine, phosphate. The above copolymers are also effective in proline and phenylalanine. The following amino acid deriva inhibiting Scales and deposits of alkaline earth metal tives can be utilized as well, hydroxyproline, Sulfates, iron (hydr)oxide, Zinc hydroxide, aluminum (hydr) Y-carboxygluta-mic acids or Salts thereof, o-phosphoSerine, oxide, clays, calcium carbonate, Silicates and other Scales. o-phosphotyrosine, O-SulfoSerine, O-Sulfotyrosine, These biodegradable copolymers are highly calcium toler o-phophothreonine, O-Sulfothreonine, S-Sulfocysteine, ant. The polymers of the present invention are more effective S-phosphocysteine, Side chain N-Substituted asparagine with and efficient as dispersants and Scale inhibitors than unmodi C to Cao alkyl, aryl, alkyl or Sulfoalkyl, o-sulfoaryl, fied polyamino acids such as unmodified polyaspartic acids. o-Sulfoalkyl, o-phospho alkyl, o-phosphoary 1, In an embodiment, the N-oxygenated hydrocarbonamide o-phosphoalkyl, c-Sulfonoary 1, c-Sulfono alkyl, 35 of the general formula (I) is N-2-hydroxyethylaspartamide c -sulfono alkyl, -(-CHCH-O-)-R and or N-2-hydroxyethylglutamide. -(-CHCHNR-), -R, where R' and R are H or a C, In an embodiment, the N-oxygenated hydrocarbonamide to C, alkyl group and R is a C, to C, alkyl group, both S of the general formula (I) N-3-hydroxypropylaspartamide or and trange from 1 to 50. N-3-hydroxypropyglutamide. The repeating molar units of formulas I-C. and I-B linked 40 In an embodiment, the N-oxygenated hydrocarbonamide in the copolymer backbone are described as the following: of the general formula (I) is N-2-hydroxypropylaspartamide or N-2-hydroxypropyglutamide. (OY), In an embodiment, the N-oxygenated hydrocarbonamide O O y of the general formula (I) is N-1-methyl-2,3- 45 N N dihydroxypropylaspartamide or N-1-methyl-2,3- H R1 dihydroxypropyglutamide. (CH2), In an embodiment, the N-oxygenated hydrocarbonamide of the general formula (I) is N-1-ethyl-2,3- (H). O 4. N 1. dihydroxypropylaspartamide or N-1-ethyl-2,3- coR H 50 dihydroxypropyglutamide. X molar unit of I-B In an embodiment, the N-oxygenated hydrocarbonamide Y(OY). of the general formula (I) is N-2,3- molar unit of I-C. dihydroxy propyla Spart amide O N-2,3- dihydroxypropyglutamide. The repeating molar units of formula II linked in the 55 In an embodiment, the N-oxygenated hydrocarbonamide copolymer backbone are described as the following: of the general formula (I) is N-l-hydroxymethyl-2,3- dihydroxypropylaspartamide or N-1-hydroxymethyl-2,3- dihydroxypropyglutamide. In an embodiment, the N-oxygenated hydrocarbonamide 60 of the general formula (I) is N-bis(2-hydroxyethyl) - aspartamide or N-bis(2-hydroxyethyl)glutamide. In an embodiment, the N-oxygenated hydrocarbonamide molar unit of II of the general formula (I) is N-(3-bis(N-hydroxyethyl) amino)propyl-1-amido aspartamide or N-(3-bis(N- If the amino acid of formula II is aspartic acid or its Salts, 65 hydroxyethyl)amino)propyl-1-amidoglutamide. the aspartic acid repeating molar units linked in the copoly In an embodiment, the N-oxygenated hydrocarbonamide mer backbone are described as shown below: of the general formula (I) is N-p or o- or 5,858,244 S 6 m-phenola Spart amide or N-p or o- or Still another advantage of the invention is to provide a m-phenolaspartamideglutamide. family of biodegradable polymers which Simultaneously In an embodiment, the N-oxygenated hydrocarbonamide disperse particulate matter and inhibit many types of Scales of the general formula (I) is N-2(2-hydroxyethoxy) in aqueous Systems, especially in industrial aqueous Sys ethylaspartamide or N-2-(2-hydroxyethoxy)ethylglutamide. temS. In an embodiment, the N-oxygenated hydrocarbonamide Another advantage of the present invention is to provide of the general formula (I) is N-dihydroxyphenylaspartamide a method of achieving high-performance Scale inhibition or N-dihydroxyphenylglutamide. using alkanolamine modified polyamino acids. In an embodiment, the N-oxygenated hydrocarbonamide Another advantage of the present invention is to provide of a general formula (I) is N-2-(2-hydroxyethoxy) ethylaspartamide or N-2-(2-hydroxyethoxy)ethylglutamide. a method of reducing Scale and deposit build-up by utilizing In an embodiment, the N-oxygenated hydrocarbonamide a new family of water soluble polymers which are biode of the general formula (I) is N-2-(2-hydroxyethylamino) gradable and are effective Scale inhibitors and dispersants. ethylaspartamide or N-2(2-hydroxyethylamino) Another advantage of the present invention is to provide ethylglutamide. an improved Scale and deposit inhibiting composition for In an embodiment, the N-oxygenated hydrocarbonamide 15 use in connection with metallic Surfaces. of the general formula (I) is N-2-methoxyethylaspartamide Still another advantage of the present invention is to or N-2-methoxyethylglutamide. provide an improved Scale and deposit inhibiting composi In an embodiment, the N-oxygenated hydrocarbonamide tion that is biodegradable. of the general formula (I) is N-(2-O-Sulfatoethyl)aspartamide A further advantage of the present invention is to provide or N-(2-o-sulfathoethyl)glutamide. an improved Scale and deposit inhibiting composition which In an embodiment, the amino acid compound of the also reduces corrosion. general formula (II) (wherein M is H or metal) is aspartic Yet another advantage of the present invention is to acid. provide a new use for N-oxygenated hydrocarbonamide and In an embodiment, the amino acid compound of the salts thereof. general formula (II) (wherein M is H or metal) is glutamic 25 Another advantage of the present invention is to provide acid. a new use for amino acids and Salts thereof. In an embodiment, the amino acid compound of the A further advantage of the present invention is to provide general formula (II) (wherein M is H or metal) is asparagine. improved Scale-inhibiting compositions which have aqueous In an embodiment, the amino acid compound of the and non-aqueous applications. general formula (II) (wherein M is H or metal) is glutamine. Additional features and advantages are described in, and In an embodiment, the amino acid compound of the will be apparent from, the detailed description of the pres general formula (II) (wherein M is H or metal) is histidine. ently preferred embodiments. In an embodiment, the amino acid compound of the DETAILED DESCRIPTION OF THE general formula (II) (wherein M is H or metal) is arginine. PRESENTLY PREFERRED EMBODIMENTS In an embodiment, the amino acid compound of the 35 general formula (II) (wherein M is H or metal) is lysine. The present invention provides an improved Scale and In an embodiment, the amino acid compound of the deposit inhibiting composition that is environmentally general formula (II) (wherein M is H or metal) is alanine. acceptable. In a preferred embodiment, the Scale inhibiting In an embodiment, the amino acid compound of the composition is a copolymer comprising at least one of general formula (II) (wherein M is H or metal) is cysteine. 40 N-oxygenated hydrocarbonamide monomers and at least one In an embodiment, the amino acid compound of the of a mino acid OO C. S. The general formula (II) (wherein M is H or metal) is glycine. N-oxygenated hydrocarbonamides or Salt thereof of the gen In an embodiment, the amino acid compound of the eral formulas I-C. and I-B as shown below: general formula (II) (wherein M is H or metal) is isoleucine. (OY), In an embodiment, the amino acid compound of the 45 general formula (II) (wherein M is H or metal) is leucine. O y In an embodiment, the amino acid compound of the HN - OM HN 1. NR1 general formula (II) (wherein M is H or metal) is methion (CH2), (CH2), C. In an embodiment, the amino acid compound of the 50 coR COM general formula (II) (wherein M is H or metal) is proline. X I-B In an embodiment, the amino acid compound of the Y(OY). general formula (II) (wherein M is H or metal) is serine. I-C. In an embodiment, the amino acid compound of the general formula (II) (wherein M is H or metal) is threonine. 55 or a mixture of forms I-C. and I-8 in ratios ranging from 1:99 In an embodiment, the amino acid compound of the to 99:1 and wherein M may be hydrogen, a metal, an alkali general formula (II) (wherein M is H or metal) is tryptophan. metalion, an alkaline earth metal ion or NH", Al", Fe", In an embodiment, the amino acid compound of the Fe"f, Zn', or mixtures thereof, m ranges from 1 to 10; in general formula (II) (wherein M is H or metal) is tyrosine. may be 1 or 2; R may be hydrogen, a C, to Cao alkyl group In an embodiment, the amino acid compound of the 60 or an aryl group or alkyl or aryl group having from one to general formula (II) (wherein M is H or metal) is valine. thirty carbon atoms, or an alkyl or aryl group that is An advantage of the present invention is to provide a new substituted with one or more of OH, SOM' (wherein M' is family of water soluble polymers which are biodegradable H or a metal), POM (wherein M is H or a metal), COM and which are effective Scale inhibitors and dispersants. (wherein M is OH, OR, or NR wherein R is an alkyl of 3 Another advantage of the present invention is to achieve 65 to 4 carbons); X may be a C to Cao alkylene or arylene high-performance Scale inhibition using alkanolamine modi (straight or branched) or a straight or branched-chain alky fied polyamino acids. lene group having one to thirty carbon atoms or a Straight or 5,858,244 7 8 branched-chain alkylene or arylene group Substituted with tryptophan, tyrosine, Valine, proline, and phenylalamine. one or more of OH, SOM (wherein M' is H or a metal), The metal M is an alkaline metal, a metalion, earth alkaline POM (wherein M is H or a metal), COM (wherein M is metal ion or NH, Al", Fe", Fe"f, Zn". The following OH, OR, or NR wherein R is an alkyl of 3 to 4 carbons); amino acid derivatives can be utilized as well; Y may be H, C to C alkyl, SOM or mixture thereof hydroxyproline, Y-carboxyglutamic acids or Salts thereof, wherein M may be hydrogen or a metal ion. o-phosphoSerine, o-phosphotyrosine, O-Sulfo Serine, Further, X (OY), may be —CHRCH (OCHRCH.) O-Sulfotyrosine, o-phophothreaonine, O-Sulfothreonine, (OCHCH)OR' or - CH-CH(NRCHCHR), OR" S-Sulfocysteine, t-phosphocysteine, Side chain N-Substituted where R is H or CH or mixtures thereof; oranges from asparagine with C to Co alkyl, aryl, alkyl or Sulfoalkyl, Zero to 50; p ranges from Zero to 50, o-p ranges from 1 to O-Sulfoaryl, o-Sulfoalkyl, o-phosphoalkyl, a-phosphoaryl, 50; r ranges from zero to 50; R is a C, to C alkyl group; o-phosphoalkyl, c-Sulfonoary 1, c-Sulfono alkyl, R is a C, to C alkyl group; R may be H, CH or SOM c -sulfono alkyl, -(-CHCHO) R', and where M may be H, alkaline earth metal ions alkalimetal -(-CHCHNR-)-R, wherein R and Rare Hora ions or N(R7), where R7 is H, a benzyl group or a C to C. C. to C alkyl group and R is a C, to C, alkyl group, both alkyl group. S and trange from 1 to 50. Acceptable examples of the 15 The repeating molar units of formulas I-C. and I-B linked N-oxygenated hydrocarbonamide compounds of the general in the copolymer backbone are described as the following: formula (I) include N-2-hydroxyethylaspartamide or N-2- hydroxyethylglutamide, N-3-hydroxypropylaspartamide or O (OY), N-3-hydroxy propyl glutamide, N- 2 - O y hydroxy propyla Spart amide O N-2- N N hydroxy propylglutamide, N-2-methyl-2, - H R1 dihydroxypropyla Spartamide o N-1-methyl-2,3- (CH2), dihydroxy propyl glutamide, N-1-ethyl-1-2, (H). O 4. N 3-dihydroxypropylaspart amide N-1-ethyl-2,3- 1. 25 coR H dihydroxy propyl glutamide, N-2,3- X molar unit of I-B dihydroxy propyla Spart amide O N-2,3- Y(OY). dihydroxypropylglutamide , N-1-hydroxymethyl-2, 3-dihydroxypropylaspartamide or N-1-hydroxymethyl-2, molar unit of I-C. 3-dihydroxypropylglutamide, N-bis (2-hydroxyethyl)aspar tamide or N-bis(2-hydroxyethyl)glutamide, N-(3-bis(N- The repeating molar units of formula II linked in the hydroxyethyl))aminopropylaspartamide or N-bis(2- copolymer backbone are described as the following: hydroxyethyl)aspartamide or N-bis (2-hydroxyethyl) glutamide, N-(3-bis(N-hydroxyethyl)) aminopropylaspartamide or N-bis(2-hydroxyethyl) aminopropylglutamide, N-p or m- or o-phenolaspartamide 35 or N-p or m- or o-phenoglutamide and -- N-dihydroxyphenyla Spart amide O molar unit of II N-dihydroxyphenylglutamide, N-2- (2-hydroxyethoxy ethylaspartamide) or N-2- ( 2-hydroxyethoxy) ethylglutamide, N-2-hydroxyethylamino)ethylaspartamide 40 If the amino acid of formula II is aspartic acid or its Salts, or N-2-(hydroxyethylamino)ethylglutamide, N-2- the aspartic acid repeating molar units linked in the copoly methoxyethylaspartamide or N-2-methoxyethylglutamide, mer backbone are described as shown below: N-(2-o-sulfatoethyl)aspartamide or N-(2-o-sulfatoethyl) glutamide. O 45 The more preferred oxygenated hydrocarbonamides of N the formula (I) are N-2-hydroxyethylaspartamide, N-2- H hydroxy propyla Spart amide, N-1-methyl-2,3- dihydroxypropyla Spart amide, N-1-ethyl-2,3- COM dihydroxypropylaspartamide and N-1-hydroxymethyl-2,3- molar unit of aspartic acid (II), C-form 50 dihydroxypropylaspartamide. COM The amino acid monomer is of the general formula (II) as shown below: NH O (II) 55 O HN - OM molar unit of aspartic acid (II), f-form R3 wherein R is a radical defined by the list of amino acids and The preferred amino acids of the formula II are aspartic amino acid derivatives appearing below. If formula (II) is 60 acid or its Salts, and glutamic acid or its Salts. The more aspartic acid, the aspartic acid unit in the copolymer is in its preferred amino acids of the formula II is aspartic acid or its C. form or B form or a mixture form of C.: B ranging from 99:1 Salts. The aspartic acid molar units in the copolymer chains to 1:99. are in the form of C-form or 3-form or a mixture at a ratio The amino acids the general formula (II) (wherein M is H of C.: B ranging from 1:99 to 99:1. or metal) include alanine, arginine, aspartic acid, asparagine, 65 All D, L and DL optical sources of formula I and II cysteine, glutamine, glutamic acid, glycine, histidine, monomers can be utilized. Mole ratios of the two monomer isoleucine, leucine, lysine, methionine, Serine, threonine, units in the polymer can range from 1:99 to 99:1. Examples 5,858,244 10 of effective mole ratios are provided in the examples pre tively. An equal amount of orthophosphate (10 ppm as PO) sented below. Preferably, the ratio of formula (I) to formula was added to each test Solution, and the inhibitor concen (II) ranges from 80:20 to 10:90, more preferably from 40:60 to 15:85. trations are listed in Table 1. The temperature of the test Appropriate dosages will depend upon the water treated solution was maintained at 158° F (70° C.). Using dilute and the minerals present in the water as indicated in the acqueous NaOH, the pH was slowly increased to 8.5 and examples presented below. Effective dosages can range from maintained during the four hour duration of the test. Mineral 0.1 ppm to 500 ppm, more preferably 5 to 50 ppm, still more preferably from 5 to 30ppm. Solubility calculations indicate that SuperSaturation values By way of example, and not limitation, examples of the for the calcium phosphate of greater than 10,000 ppm and present invention will now be given. Other Scales which can magnesium phosphate of greater than 600 ppm were initially be reduced by using the polymers invented are barium present. As a result, the System was under highly a stressed Sulfate, calcium carbonate, calcium oxylate, calcium Sulfate, condition. At the conclusion of each test, each Solution was etc. filtered with a 0.45 um filter and the orthophosphate con EXAMPLES centration was determined spectrophotometrically after for The inhibitory power of the polymers of the present 15 mation of a blue phosphomolybdate complex. invention were evaluated using activity tests employing test chemicals of reagent grade. Specifically, calcium, The inhibition of calcium and magnesium phosphate Scale magnesium, Zinc and bicarbonate were respectively Supplied by reagent grade CaCl2.H2O, MgSO.7H2O, ZnSO.7H2O, formation is determined using Equation 1 below: and NaHCO.7HO respectively. The orthophosphate was Equation 1 Supplied by HPO. The polymer concentrations used in % inhibition = filtered - blank (Eq ) each test were indicated in Tables 1-5. initial - blank Each test Solution was stirred with a teflon coated stir bar in a jacketed glass beaker. The temperature was maintained where, using a Landa recirculating, constant-temperature basin. The pH was determined with Fisher Accumat meter (model 25 filtered=concentration of phosphate ion in filtrate in the 6100A) and a combination electrode. The pH meter was presence of the inhibitor of the present invention after calibrated with two standard buffers (pH 7 and 10) and four hours, corrections were made for temperature changes. initial=concentration of phosphate ion in the test Solution EXAMPLE I at time Zero; and Calcium and Magnesium Phosphate Scale blank=concentration of phosphate ion in the filtrate in the Inhibition Test absence of any inhibitor after four hours. Soluble calcium and magnesium were added to provide Using the above method, a number of polymer composi initial concentrations of 250 and 125 ppm as CaCO, respec tions were tested. The results are listed in Table 1.

TABLE 1. Calcium and Magnesium Phosphate Scale Inhibition with N Oxygenated hydrocarbonamidefamino acid copolymers (250 ppm Ca"/125 ppm Mg"/10 ppm PO unless where it is indicated % Phosphate salt inhibition ppm polymer dose Sample Polymer composition, Mol % MW 2 3 4 5 6 7 8 10 15 20 3O A1 50/50 L-2-hydroxyethylaspartamide/aspartic 6OOO 9 8 23 SO 67 82 86 96 98 acid A1 50/50 L-2-hydroxyethylaspartamide/aspartic 6OOO 4 5* 11* 35* 57* acid A2 28/72 L-2-hydroxyethylaspartamide/aspartic 33OOO 8 9 89 98 acid A3 50/50 L-2-hydroxyethylaspartamide/aspartic 6SOO 9 10 31 61 81 88 82 acid A4 10/90 L-2-hydroxyethylaspartamide/aspartic 6400 9 1O 1O 1O acid A5 20/80 L-2-hydroxyethylaspartamide/aspartic 6SOO 8 1O 12 1O acid A6 80/20 L-2-hydroxyethylaspartamide/aspartic 33OO 9 9 11 42 acid B1 29/71 L-2-(2-methyl-1,3- 34OOO 9 9 86 95 dihydroxypropylaspartamidefaspartic acid C1 polyaspartic acid 7OOO 8 C2 polyaspartic acid 25OOO 9 C3 polyaspartic acid 9OOOO 4 C4 polyaspartic acid 92OOO 4 C5 polyaspartic acid 94OOO 6 D1 non-biodegradable commercial product 1 8 13 91 99 *These tests were done under high hardness stress conditions (1200 ppm Ca" and 10 ppm orthophosphate). 5,858,244 11 12 EXAMPLE II EXAMPLE III Iron (Hydr)oxide Scale Inhibition Test In a Standard test, Soluble calcium and magnesium were Zinc Hydroxide Scale Inhibition Test added to provide initial concentrations of 360 and 200 ppm as CaCO respectively. An equal amount of Soluble iron (10 ppm) was added to each test Solution, and the inhibitor In a Standard test, Soluble calcium and magnesium were concentrations are listed in Table 2. The temperature of the added to provide initial concentrations of 150 and 100 ppm test solution was maintained at 140° F (60° C.). Using a as CaCO respectively. An equal amount of Soluble Zinc (5 dilute aqueous NaOH solution, the pH was slowly increased ppm) was added to each test Solution, and the inhibitor to 8.5 and maintained during the two hour duration of concentrations are listed in Table 3. The testing bottles were heating at 140 F. (60° C.). At the end of 2 hour heating Sealed. The temperature of the test Solution was maintained period, the Samples were removed from the water bath and at 110° F (43° C.). Using a dilute aqueous NaOH solution, allowed to stand undisturbed at room temperature for 24 the pH was slowly increased to 9.1 and maintained during hours. The Samples were then taken from the top portion of 15 the 24 hour duration of the test. At the end of 24 hour heating each aliquot and analyzed for iron content by atomic absorp period, the solution was filtered (0.2 um) and the filtered tion analysis. The iron concentration in the aliquot correlates Sample was analyzed for Zinc concentration by atomic directly with the inhibition activity of the polymer. That is, absorption analysis. the higher the iron concentration in the top part of the aliquot, the higher was the inhibition activity of the polymer The inhibition of zinc (hydr)oxide is determined as indi tested. cated as Equation 3: The inhibition of iron (hydr)oxide is determined as indi filtered - blank (Equation 3) cated as Equation 2: % inhibition = x 100 initial - blank 25 final - blank (Equation 2) % inhibition = x 100 initial - blank where, where, final=concentration of iron ion in unfiltered Samples of the filtered=concentration of Zinc ion in filtrate in the pres top portion after 2 hours heating and 24 hours Standing ence of the inhibitor of the present invention after 24 in the presence of inhibitor; hours, initial=concentration of iron ion in the test Solution at time initial=concentration of Zinc ion in the test Solution at Zero; and time Zero; blank=concentration of iron ion in unfiltered Samples of blank=concentration of Zinc ion in filtrate Samples in the the top portion after 2 hours heating and 24 hours 35 absence of the inhibitor of the present invention after Standing in the absence of inhibitor. 24 hours. Using the above method, a number of polymer composi Using the above method, a number of polymer composi tions were tested. The results are listed in Table 2. tions were tested. The results are listed in Table 3.

TABLE 2 Iron (Hydr)oxide Scale Inhibition with N-oxygenated hydrocarbonamide? amino acid copolymers Iron (hydr)oxide Scale inhibition at ppm polymer dose Sample Polymer composition Mol % MW 3 5 1O 2O A1 50/50 L-2-hydroxyethylaspartamide/aspartic 16OOO 21 92 92 acid A2 28/72 L-2-hydroxyethylaspartamide/aspartic 33000 O 92 1OO 95 acid A4 10/90 L-2-hydroxyethylaspartamide/aspartic 16400 O O 5 acid A5 20/80 L-2-hydroxyethylaspartamide/aspartic 165OO O 29 76 acid A6 80/20 L-2-hydroxyethylaspartamide/aspartic 133OO 4 28 1OO acid B1 29/71 L-2-(2-methyl-1,3- 34OOO 85 dihydroxypropylaspartamidefaspartic acid C1 polyaspartic acid 17OOO 7 C2 polyaspartic acid 25OOO 14 C3 polyaspartic acid 90OOO 7 C4 polyaspartic acid 92OOO 1. C5 polyaspartic acid 94OOO D1 non-biodegradable commercial product 1 O 5,858,244 13 14

TABLE 3 Zinc Hydroxide Scale Inhibition with N-oxygenated hydrocarbonamide aspartic acid copolymers Zinc Hydroxide Inhibition at ppm polymer dose Sample copolymer composition MW 1O A1 50/50 L-2- 16OOO 24 71 hydroxyethylaspartamide/aspartic acid A4 10/90 L-2- 16400 4 13 hydroxyethylaspartamide/aspartic acid A5 20/80 L-2- 16400 75 8O hydroxyethylaspartamide/aspartic acid B1 29/71 L-2-(2-methyl-1,3- 34OOO 70 63 dihydroxypropyl)aspartamide/aspartic acid D1 non-biodegradable commercial product 1 87 92

EXAMPLE IV 2O % clay disp. = final treatment turb. - final blank turb. X (Equation 4) Clay Particulate Inhibition Test initial blank turb. - final blank turb. This test examines the dispersion ability of the polymers of the present invention for particulate matter. The assump tion is that polymers which promote disperSancy will reduce

TABLE 4 Clay Particulate Dispersancy with N-oxygenated hydrocarbonamide?amino acid copolymers Clay particulate dispersancy at Sample copolymer composition MW ppm polymer dose 5 ppm A4 10/90 L-2- 16400 40 hydroxyethylaspartamidefaspartic acid A5 20/80 L-2- 165OO 32 hydroxyethylaspartamidefaspartic acid A6 80f2O L-2- 133OO 52 hydroxyethylaspartamidefaspartic acid B1 29/71 L-2-(2-methyl-1,3- 34OOO 40 dihydroxypropyl)aspartamide/aspartic acid D1 non-biodegradable commercial product 1 50 the Settling rate of clay particles and particulate matter in EXAMPLE V general. The dispersed clay causes higher turbidity. 45 A standard Suspension of particulate (clay) was prepared Polymer Calcium Tolerance Test (Polymer in an aqueous Solution of 300 ppm Soluble calcium as Solubility Test) CaCO. One liter of this solution was placed in a Waring This test evaluates anionic polymers for use as dispersants blender to which 100 ml of china clay was added. The clay or Scale inhibitors. Dispersant polymers prevent deposition was dispersed for 60 Seconds on low Setting then immedi 50 of Suspended particles Such as calcium and magnesium ately dispersed equally amount in four 250 ml graduated phosphate, iron (hydr)oxide, Zinc hydroxide, calcium cylinders. One cylinder became the blank while the remain carbonate, calcium Sulfate, barium Sulfate, calcium oxylate ing three test inhibitor treatment. The blank was returned to clays, etc., which are either present in the make-up water, the blender and re-dispersed for 20 seconds on low. This added as treatments, or which form due to corrosion or Suspension was returned to its graduated cylinder. A Sample 55 precipitation in the System. HardneSS can be varied to was withdrawn from a level of 100 ml and the turbidity was determine conditions where the polymer can be an effective determined with a turbidimeter (Hach 2100A). This repre dispersant. This test predicts the dispersant (Scale inhibitor) Sented the initial reading for blank. The Suspension was activity of anionic polymers. Anionic polymers become returned to the graduated cylinder and allowed to Settle for insoluble at high calcium concentration and elevated tem 2 hours. Treatment cylinders are prepared by returning the 60 perature. The higher the calcium, the lower the temperature remaining Suspensions, in turn, to the blender, followed by at which turbidity occurs. Polymers tend to be good dis the addition of 5ppm inhibitor and re-dispersed for 20 persants if they are Soluble at conditions of calcium and Seconds on low. Treatment cylinders are allowed to Settle for temperature. Conversely, polymers will be poor dispersants 2 hours. At the end of 2 hours, samples are withdrawn from under conditions where they precipitate. a level of 100 ml and turbidity readings taken. 65 Dilute calcium and polymer Solutions were mixed at room Percent clay disperSancy is determined using the follow temperature to give 100 ppm actives and either 200 or 400 ing Equation 4 and the results are listed in Table 4. ppm soluble calcium as CaCO. The pH was adjusted to 8.5 5,858,244 15 16 with dilute NaOH solution. A thermometer was inserted and phoric acid, a phosphonic acid (such as HEDP, PBTC), or the test vessel was covered with an aluminum foil. The test POs or a mixture of them or a Sulfur-containing dehydrating Solution was then heated gradually. The temperature was agent Such as Sulfurtrioxide, Sulfurtrioxide precursors, Sulfur noted when turbidity occurred. oxygen acids, Sulfonic acids or any other acid or in the Using this method, a number of polymers were tested and absence of a catalyst as would be apparent to those skilled the results are listed in Table 5. For polymers provided in in the art and as described in the journal literature. The accordance with the present invention, no turbidity was polySuccinimide can also be Synthesized from maleic anhy visible even after the samples reached 100° C. Additional dride and ammonium, maleic acid and ammonium or from aliquots of calcium Stock Solutions were added to the boiling mono or diammonium moleate. The poly(Succinimide) solutions to give 800 and 1600 ppm Ca. After several obtained may or may not be purified before it is used to react minutes, there was still no turbidity. These results predict with alkanolamines or other amine derivatives. excellent dispersant and Scale inhibition activity for these The reaction Solvent is water, where the polySuccinimide polymers in the present invention under conditions of high is Suspected and the oxygenated hydrocarbonamine is then hardneSS and high temperature. added at a pH ranging from 2 to 13, with a preferred pH

TABLE 5 Polymer Calcium Tolerance (Polymer Solubility) Test Results Turbidity Temperature at ppm Calcium

Sample Polymer composition MW 2OO 400 8OO 1OOO 16OO A1 50/50 L-2 16OOO CAB CAB CAB CAB hydroxyethylaspartamide/aspartic acid copolymer A2 28/72 L-2- 33OOO CAB CAB CAB CAB hydroxyethylaspartamide/aspartic acid copolymer C1 polyaspartic acid 17000 60° C. - C2 polyaspartic acid 25OOO 47 C. - D1 non-biodegradable commercial CAB 74°C - 59 C polymer I E1 non-biodegradable commercial CAB polymer II F1 non-biodegradable commercial 55 C. - polymer III G non-biodegradable commercial CAB polymer IV * CAB = Clear At Boiling.

The data presented in Tables 1-5 demonstrate that the 40 ranging from 5 to 11. The reaction temperature is 0 to 100 polymers provided in accordance with the present invention C., preferred 20 to 60° C. The reaction time is 1 to 24 hours, are capable of functioning positively as a Scale inhibitor and preferably 2 to 10 hours. The unreacted polysuccinimide dispersant at a Sufficient dose in environments Such as mol units in the polymer are then hydrolyzed with a base cooling towers, boilers and the like. The polymers provided such NaOH, KOH or NHOH or another base to produce the in accordance with the present invention can be used alone 45 copolymers or terpolymers or polypolymers. This method or combined with any other biodegradable or non usually produces a polymer with high molecular weight. biodegradable ingredients for the purpose of Scale inhibition The reaction solvent is DMF, DMSO or other organic and/or dispersion. Solvents, where the poly Succinimide is dissolved in the Solvent. The oxygenated hydrocarbonamine or a Solution of SYNTHESIS OF N 50 the oxygenated hydrocarbonamine is added to the Solution of OXYGENATEDHYDROCARBONAMIDE the poly Succinimide. The reaction product is then precipi AMINO ACID COPOLYMERS tated with a leSS polar Solvent Such as alcohol or acetone. The above-described copolymers were Synthesized using The precipitate is collected dried or undried and Sus pended in water. Abase such as NaOH is added to hydrolyze the following procedures. First, polysuccinimide with MW the remaining poly Succinimide mol units to produce the weight of 500 to 20,000 of L- or D- or DL-aspartic acid or 55 copolymer. The reaction conversion is usually quantitative. glutamic acid was reacted with an oxygenated hydrocarbon Thus, the composition (the molar ratio of amine or with a mixture of an oxygenated hydrocarbonamine oxygenated hydrocarbonamine/amino acid) can be con and one or more other oxygenated hydrocarbonamine at trolled by controlling the reactant molar ratio ratioS of oxygenated hydrocarbonamine/polySuccinimide oxygenated hydrocarbonamine/poly Succinimide. The ranging from 0.01/1.00 to 0.99/1.00 in an organic solvent 60 molecular weight of the resulting copolymer can be con such as DMF, DMSO and the like or in an aqueous medium trolled by controlling the reaction temperature and reaction or an aqueous-organic medium at a Suitable temperature for time as well as the molecular weight of the Starting poly Suc a Suitable reaction period. cinimide. Next, the poly(succinimide of L- or D- or DL-aspartic Specific examples of copolymers are listed in Table 6 and acid) was Synthesized by heating L- or D- or DL-aspartic 65 the Synthesis of those examples is explained below. acid either in the presence of an acid catalyst Such as For polymer numbers 4 and 5 of Table 6 a solution of orthophosphoric acid, polyphosphoric acid, Super polyphoS ethanolamine (1.53 g, 0.025 mol 1.0 equivalent) in deion 5,858,244 17 18 ized water was added to a magnetically Stirred Suspension of aspartic acid copolymer was dialyzed (membrane MWCO polysuccinimide (2.5g, 0.025 mol) in deionized water (20.4 500) for 30 hours. The dialyzed solution was concentrated to g) over a 17 minute period. The Suspension was stirred at give pure polymer No. 2. The product molecular weight room temperature for 28 hours. Almost all Solids disap determined by GPC and composition determined by C peared within 50 minutes to form a clear Solution. The pH NMR spectroscopy are summarized in Table 6. range was then adjusted from 9.4 to 8.7 to afford crude Polymer No. 19 was prepared as follows: 2-amino-2- N-2-hydroxyethylaspartamide/aspartic acid copolymer. methyl-1,3 propanediol (1.39 g, 0.0125 mol) in dry DMF Dialysis of polymer no. 4 to afford pure (polymer no. 5). The (10 ml) was added to a stirred Solution of polySuccinimide product molecular weights determined by GPC and compo (1.23g, 0.0125 mol) in dry DMF (15 g). After the solution sitions determined by C NMR spectroscopy are summa was stirred at room temperature for 20 hours, 150 ml of 1:2 rized in Table 6. ethanol/cyclohexane was added. The resultant precipitate Polymer No. 1 was similarly prepared but only 0.50 was centrifuged. The Supernatant was decanted and the equivalent of ethanolamine was charged. After a Suspension solids was washed with ethanol. This procedure was of polysuccinimide (5.0 g, 0.050 mol) in deionized water (35 repeated once. The Solids were dried at 50 C. under a g) was stirred with ethanolamine (1.53 g, 0.0251 mol, 0.50 Vacuum and then Suspended in deionized water. 5.0 g of equivalents) at room temperature for 20.8 hours, 0.041 15 10.0% NaOH solution was added dropwise to the stirred moles of NaOH solution was added dropwise to form a clear Suspension to form a clear Solution. The Solution was solution of pH 12.98. The solution was further stirred for I acidified to pH 2.1 and then dialyzed (membrane MWCO 12 hour and then neutralized with dilute HCl to pH 6.7. Dialysis to 14K) for 3 days. The dialyzed solution was concentrated (membrane MWCO 12 to 14K) of the crude product to afford pure polymer no. 16. The product MW determined afforded polymer No. 1. C NMR analysis indicated that with GPC and composition determined with "C NMR most of residual ethanolamine was not removed. The Spectroscopy are Summarized in Table 6. molecular weight and ethanolamine incorporation are Sum For polymer No. 22, to a stirred solution of poly(suc) marized in Table 6. (10.0 g, 0.102 mol) in DMF (80 ml) was added dropwise a Polymer No. 2 was prepared by adding dry DMF (60 g) solution of ethanolamine (1.87 g., 0.0306 mol) in DMF (15 and ethanolamine (4.66 g., 0.0765 mol, 0.50 equivalent) in 25 ml). The solution was further stirred at room temperature for dry DMF(10 ml) to a stirred powder of polysuccinimide 15 hours. SODMF(14.0 g, 0.092 mol) and pyridine (10.0 (15.0 g, 0.153 mol) in a 250 ml flask. The solution was g) were added. The solution was stirred at 22°–40° C. for 24 stirred at room temperature for 4 hours and at 120 to 150 hours. 180 ml of ethanol was added. The precipitated C. for 1 hour 35 min. After the Solution was cooled to room polymer product was collected by filtration, dried in vacuo, temperature, 200 ml of ethanol was added. The precipitate ground and Suspended in deionized water (60 g). 50% of was filtered in vacuum, dried at 70 to 80 C. and vacuumed NaOH (8.16 g) was added dropwise to the stirred suspension to give 9.7 g of Solids. The Solids were ground and SuS at pHs 11 to afford crude EAS/ASP copolymer. Dialysis of pended in deionized water (60 g). A NaOH solution (4.1 g the crude product gave pure EAS/ASP copolymer polymer of 50% NaOH and 7.0 g of deionized water) was added over No. 22. The produce MW determined with GPC and com 25 minutes at pH less than or equal to 11.8. The resultant 35 position determined with "C NMR spectroscopy are sum Solution was further stirred for 50 minutes and then neu marized in Table 6. tralized to pH 7.5 to afford almost pure ethanolamine Examples of the copolymerS Synthesized in addition to polyaspartic acid. Part of N-2-hydroxyethylaspartamide/ those discussed above are listed in Table 6.

TABLE 6 Examples of N-oxygenated hydrocarbonamidefamino acid Copolymers M% of alkanol MW of amine reaction temp & reaction reaction product product polymer No. polysuc charged time medium conversion composition MW 1. 94OOO 50% EA rt, 20 h. water 56% 28/72 33OOO HEA/ASP 2. 72OOO 50% EA rt, 4 h DMF 100 50/50 16OOO 120-50° C., 1.5 h HEA/ASP 3. 72OOO 50% EA rt, 4 h DMF 100 50/50 165OO 120-50, 1.4 h. HEA/ASP 4. 66OOO 100% EA rt, 27 h water 30 30/70 6OOOO HEA/ASP 5. 28/72 33OOO HEA/ASP 6. 48OOO 10% EA rt, 3.3 h. DMF 100 10/90 16400 120-50, 1.6 h HEA/ASP 7. 48OOO 20% EA rt, 4 h DMF 100 20/80 165OO 120-65 C., 4.2 h HEA/ASP 8. 72OOO .4% EA rt, 4 h DMF 100 4/96 94OO 120-65 C., 4.2 h HEA/ASP 9. 6794 96.OO HEA/ASP 10. 72OOO 6% EA 150-80° C., 5 h DMF 100 6794 7100 HEA/ASP 11. 48OOO 35% EA rt, 4 h DMF 100 35/65 94OO 130-75° C., HEA/ASP 1.3 h. 5,858,244 19 20

TABLE 6-continued Examples of N-oxygenated hydrocarbonamidefamino acid Copolymers M% of alkanol MW of amine reaction temp & reaction reaction product product polymer No. polysuc charged time medium conversion composition MW 2. 48OOO 30% EA rt, 4 h DMF OO 30/70 1OOOO 20-60° C., 1 h HEA/ASP 3. 48OOO 25% EA rt, 5 h DMF OO 25/75 11OOO 40–55° C., 0.9 h HEA/ASP 4. 48OOO 40% EA rt, 3.5 h DMF OO 40/60 8300 20-60° C., HEA/ASP .3 h. 5. 48OOO 27% EA rt, 4.4 h. DMF OO 30/70 29OOO 80-100° C., HEA/ASP h 6. 48OOO 30% EA rt, 5 h DMF OO 30/70 35OOO 10–30°C., HEA/ASP O.S. h. 7. 48OOO 80% EA rt, 3 h DMF OO 80f2O 133OO 20-65 C., HEA/ASP .3 h. 8. 48000 30% APO rt, 22 h DMF OO 30/70 37OOO 60-80° C., HPA/ASP h 9. 94OOO 100% rt, 20 h. water 29 29/71 34OOO AMPDe MDHA/ASPf 2O. 94OOO 10% Tris8 50° C., 5 h. DMF 10 10/90 46OOO Tris/ASP 21. 72OOO 7% rt, 2 h DMF 100 7/93 MEA/ASP 107OO MEA rt-145° C., 1.3 h. 145–160° C., O.S. h. 22. 72OOO 30% EA rt, 15 h DMF 98 29/71 SEA/ASP 51000 then SO.DMF/py 22-40, 24 h. EA: ethanolamine. HEA/ASP copolymer = N-(2-hydroxyethyl)aspartamide/aspartic acid copolymer: APO: 1-amino-2-propanol. "HPA/ASP copolymer: N-(2-hydroxypropyl)aspartamide/aspartic acid copolymer. AMPD: 2-amino-2-methyl-1,3-propanediol. N-(1-methyl-2,3-dihydroxypropyl)aspartamide/aspartic acid copolymer. 8Tris: tris(hydroxymethyl) amino methane. "Tris: N-(1-hydroxymethyl-2,3-dihydroxypropyl)aspartamide/ aspartic acid copolymer. 40 This invention is applicable to industries where Scale acids in amounts ranging from 0.1 to 500 ppm may also be inhibition in aqueous Systems is desirable, Such as industries used alone or in combination with one or more other using cooling towers and the like. Copolymers comprising at corrosion inhibitorS Such as phosphorous containing inor least one of N-oxygenated hydrocarbonamides and at least ganic chemicals. Such as phosphates, pyrophosphates, poly one of amino acids in amounts ranging from 0.1 to 500 ppm 45 phosphates, hydroxycarboxylic acids or their Salts. Such as may be used alone or in combination with one or more Scale gluconic acid, glucaric acid; Zn", Ce'", MoC), VO, inhibitorS Such as polyacrylate, polymethylacrylate, a WO. Such combinations may exert a synergistic effect in copolymer of acrylic acid and methacrylic acid, a copolymer terms of corrosion inhibition. of acrylic acid and acrylamide, polymaleic anhydride, a Copolymers comprising at least one of copolymer of acrylic acid and maleic acid copolymer, polyol 50 N-oxygenated hydrocarbonamides and at least one of amino esters, 1-hydroxyethylidene-1,1-diphosphonic acid, acids in amounts ranging from 0.1 to 1000 ppm may also be 2-phosphono-butane-1,2,4-tricarboxylic acid (PBTC), used alone or in combination with one or more biocides Such amino tri(methylene phosphonic acid), an acrylic acid/ as oxidizing biocides, e.g., Cl, NaOCl, NaOBr, or nonoxi acrylamide/amino methane Sulfonate terpolymer, polyaspar dizing biocides, e.g., glutaldehyde, isothiazolinones (i.e., tic acid and mixtures thereof. Such combined compositions 55 5-chloro-2-methyl-4-isothiazolin-3-one or 2-methyl-4- may exert a Synergistic effect in terms of corrosion isothiazoli-3-one) or Kathon WT, (a product of Rohm and inhibition, Scale inhibition and disperSancy. Haas Company of Philadelphia, Pa.) sulfamic acid Copolymer S comprising at least one of stabilized bleach and Sulfamic acid-stabilized bromine. Such N-oxygenated hydrocarbonamides and at least one of amino combinations may exert a Synergistic effect in terms of acids in amounts ranging from 0.1 to 500 ppm may also be 60 corrosion inhibition, Scale inhibition and bacterium control. used alone or in combination with one or more yellow metal In addition, copolymers comprising at least one of corrosion inhibitorS Such as benzotriazole, tolyltriazole, N-oxygenated hydrocarbonamides and at least one of amino mercaptobenzothiazole and other azole compounds. Such acids in amounts ranging from 0.1 to 100 ppm may be used combinations may exert a Synergistic effect in terms of alone or in combination with Scale inhibitors, yellow metal corrosion inhibition. 65 corrosion inhibitors, biocides and other chemical additives. Copolymer S comprising at least one of It should be understood that various changes and modi N-oxygenated hydrocarbonamide and at least one of amino fications to the presently preferred embodiments described 5,858,244 21 22 herein will be apparent to those skilled in the art. Such thereof, wherein M' is selected from the group consisting of changes and modifications can be made without departing H and a metal; R is selected from the group consisting of from the Spirit and Scope of the present invention and hydrogen, an alkyl group and an aryl group; X is Selected without diminishing its attendant advantages. It is therefore from the group consisting of alkylene and arylene; X(OY), intended that Such changes and modifications be covered by is selected from the group consisting of -CHRCH the appended claims. (OCHRCH),(OCH2CH2)2OR" and -CHCH What is claimed: (NRCHCHR)-OR" wherein R is selected from the group consisting of H, CH and mixtures thereof, oranges 1. A method of reducing Scale build-up on metallic from Zero to 50; p ranges from Zero to 50, o-p ranges from Surfaces caused by an aqueous System, the method compris 1 to 50; r ranges from zero to 50; R' is an alkyl group; R ing: is an alkyl group; R is selected from the group consisting adding a Scale inhibiting composition to the aqueous of H, CH and SOM wherein M is selected from the System at a Sufficient dose to reduce Scale build-up, the group consisting of H and alkaline earth metal ions and composition comprising a polymer formed from at least N(R7), wherein R7 is selected from the group consisting of one N-oxygenated hydrocarbonamide monomer and at H, a benzyl group and an alkyl group. least one of amino acid monomer. 15 5. The method of claim 1, where in the 2. The method of claim 1, wherein said Sufficient dose N-oxygenated hydrocarbonamide has a formula Selected ranges from about 0.1 ppm to about 500 ppm. from the group consisting of 3. The method of claim 1, where in the N-oxygenated hydrocarbonamide has the formula (OY), O y O HN - OM HN 1. NR1 HN - OM (CH2), and (CH2), (CH2), 25 coR COM CONR1 X Y(OY). I-B Y(OY). I-C. I-C. wherein M is Selected from the group consisting hydrogen, alkaline earth metals, alkali metals, NH, Al". Fe', Fe" wherein M is Selected from the group consisting hydrogen, and Zn'; n is selected from the group consisting of 1 and alkaline earth metals, alkali metals, NH, Al", Fe', Fe" 2, m ranges from 1 to 10; Y is Selected from the group and Zn'; n is selected from the group consisting of 1 and consisting of H, an alkyl group and SOM' and mixtures 2, m ranges from 1 to 10; Y is Selected from the group thereof, wherein M' is selected from the group consisting of consisting of H, an alkyl group and SOM and mixtures 35 H and a metal; R is selected from the group consisting of thereof, wherein M' is selected from the group consisting of hydrogen, an alkyl group and an aryl group; X is Selected H and a metal; R is selected from the group consisting of from the group consisting of alkylene and arylene; X (OY), hydrogen, an alkyl group and an aryl group; X is Selected is selected from the group consisting of -CHRCH from the group consisting of alkylene and arylene; X(OY), (OCHRCH) (OCH2CH)OR" and —CHCH is selected from the group consisting of -CHRCH 40 (NRCHCHR)-OR wherein R is selected from the (OCHRCH)(OCHCH), OR" and —CHCH group consisting of H, CH and mixtures thereof, oranges (NRCHCHR)-OR" wherein R is selected from the from Zero to 50; p ranges from Zero to 50, o-p ranges from group consisting of H, CH and mixtures thereof, oranges 1 to 50; r ranges from zero to 50; R' is an alkyl group; R from Zero to 50; p ranges from Zero to 50, o-p ranges from is an alkyl group; R is selected from the group consisting 1 to 50; r ranges from zero to 50; R' is an alkyl group; R 45 of H, CH and SOM’ wherein M° is selected from the is an alkyl group; R is selected from the group consisting group consisting of H and alkaline earth metal ions and of H, CH and SOM wherein M° is selected from the N(R7), wherein R7 is selected from the group consisting of group consisting of H and alkaline earth metal ions and H, a benzyl group and an alkyl group. N(R), wherein R is selected from the group consisting of 6. The method of claim 1, wherein the amino acid is H, a benzyl group and an alkyl group. 50 Selected from the group consisting of alanine, arginine, 4. The method of claim 1, where in the aspartic acid, asparagine, cysteine, glutamine, glutamic acid, N-oxygenated hydrocarbonamide has the formula glycine, histidine, isoleucine, leucine, lysine, methionine, Serine, threonine, tryptophan, tyrosine, Valine, proline, (OY), phenylalanine, hydroxyproline, Y-carboxyglutamic acids, O y 55 Salts of Y-carboxyglutamic acids, o-phosphoSerine, o-phosphotyrosine, O-SulfoSerine, O-Sulfotyrosine, HN - R1N o-phophothreonine, O-Sulfothreonine, S-Sulfocysteine, (CH2), S-phosphocysteine, Side chain N-Substituted asparagine with COM C to Cao alkyl, aryl, alkyl or Sulfoalkyl, O-Sulfoaryl, 60 o-Sulfo alkyl, o-phospho alkyl, o-phosphoary 1, I-B o-phosphoalkyl, c-Sulfonoalkyl, -(-CHCH-O-)-R' and -(-CHCH-NR-)-R, wherein R' and R are wherein M is Selected from the group consisting hydrogen, Selected from the group consisting of H and a C to C alkyl alkaline earth metals, alkali metals, NH, Al", Fe', Fe" group and R is a C, to C, alkyl group, both S and trange and Zn'; n is selected from the group consisting of 1 and 65 from 1 to 50. 2, m ranges from 1 to 10; Y is Selected from the group 7. The method of claim 1 , where in the consisting of H, an alkyl group and SOM and mixtures N-oxygenated hydrocarbonamide is Selected from group 5,858,244 23 24 consisting of N-2-hydroxyethylaspartamide, N-2- hydroxyethyl)) a mino propylglutamide, N-p- hydroxyethyglutamide, N-3-hydroxypropylaspartamide, phenolaspartamide or N-p-phenolglutamide, N-m- N-3-hydroxy propyl glutamide, N- 2 - phenola Spartamide, N-m-phenolglutamide, N-o- hydroxypropylaspartamide, N-2-hydroxypropylglutamide, p he no la Spart amide, N-m-phenol glutamide, N-1-methyl-2,3-dihydroxypropylaspartamide, N-1-methyl 2,3-dihydroxy propylglutamide, 1 - ethyl-2,3- N-dihydroxyphenylaspartamide dihydroxyphenylglutamide, dihydroxy propyla Spart amide, 1 - ethyl-2,3- N-2 (2-hydroxyethylamino)ethylaspartamide, N-2-(2- dihydroxy propyl glutamide, 2,3- hydroxyethylamino) ethylglutamide, N-2- dihydroxy propyla Spart amide, N-2,3- methoxyethylaspartamide, N-2-methoxyethylglutamide, N dihydroxypropylglutamide, N-1-hydroxymethyl-2,3- (2-o-sulfatoethyl) aspartamide, N-(2-o-sulfatoethyl) dihydroxypropylaspartamide, N-1-hydroxymethyl-2,3- glutaraide, N-2-(2-hydroxyethoxy) ethylaspartamide, and dihydroxypropylglutamide, N-bis(2-hydroxyethyl) N-2-(2-hydroxyethoxy) ethylglutamide. aspartamide, N-bis(2-hydroxyethyl)glutamide, N(3-bis(N- hydroxyethyl))aminopropylaspartamide, N-(3-bis(N-