METHOD OF CONTROLLING SCALE IN AQUEOUS SYSTEMS

1 . A water treatment polymer formed from a polymerization mixture comprising:

(i) at least one water-soluble carboxylic acid monomer, or salt or anhydride thereof, present in an amount of 10-99.999 mol % based on 100 mol % of the polymer;

(ii) at least one quarternized naphthalimide fluorescent monomer comprising either (a) Structure (I) comprising less than 8 mol %, based on 100 mol % of total Structure (I), of Structure (III) or (b) Structure (II) comprising less than 8 mol %, based on 100 mol % of Structure (II), of Structure (VI), wherein:

Structure (I) is:

wherein

R 4 and R 41 are independently selected from H, hydroxy, alkoxy, aryloxy, arylalkoxy, alkylaryloxy, (meth)allyloxy, vinylbenzyloxy, heteroaryl, —NO 2 , C 1 -C 4 alk-O—(CHR 5 CH 2 O—) n , —CO 2 H or a salt thereof, —SO 3 H or a salt thereof, —PO 3 H 2 or a salt thereof, -alkylene-CO 2 H or a salt thereof, -alkylene-SO 3 H or a salt thereof, and -alkylene-PO 3 H 2 or a salt thereof;

n=1-10;

R 1 and R 2 are independently C 1 -C 4 alkyl;

R 3 is selected from (meth)allyl, (meth)acryl, 2-hydroxy-3-(meth)allyloxypropyl, 1-hydroxy-3-(meth)allyloxypropyl, 2-(hydroxy)-3-(ethoxy)-propyl, 3-(allyloxy)-2-(3-(allyloxy)-2-hydroxypropoxy)-propyl, vinylbenzyl, 3-(meth)acrylamidopropyl, and 2-(meth)acryloyloxy ethyl, or alkyl;

R 5 is selected from H and C 1 -C 4 alkyl;

A is selected from the group consisting of alkyl, alkoxyalkyl, alkylamidoalkyl, arylalkyl or nonexistent; with the proviso that when A is nonexistent, B is nitrogen and B is bonded directly to the imide nitrogen;

B is sulfur or nitrogen with the proviso that when B is sulfur only one of R 1 or R 2 is present; and

X − is an anionic counter ion;

Structure (II) is:

wherein

m=1-10;

R 7 and R 8 and R 9 are each independently an alkyl and may be the same or different;

R 6 is selected from the group consisting of vinyl, alkenyl, and (meth)allyl;

D is oxygen or nonexistent, with the proviso that when D is nonexistent, (CH 2 ) m is bonded directly to a carbon on the ring; and

X − is an anionic counter ion;

Structure (III) is:

wherein A, B, R 1 , R 2 , R 4 , and R 41 are as defined above; and

Structure (VI) is:

wherein D, m, R 7 -R 9 , and X − are as defined above and R 66 is H or alkyl;

said quaternized naphthalimide fluorescent monomer being present in said water treatment polymer in an amount of 0.001-10 mol % based on 100 mol % of the water treatment polymer; and

said quaternized napthalimide fluorescent monomer being incorporated into said water treatment polymer to an extent equal to or greater than 90%.

2 . The polymer of claim 1 , wherein the polymerization mixture includes at least one monomer of Structure (I), wherein R 4 is alkoxy selected from methoxy, ethoxy, propyloxy, isopropyloxy, n-butoxy, isobutoxy, and tert-butoxy or hydroxy, and R 41 is H and R 3 is selected from (meth)allyl, (meth)acryl, 2-hydroxy-3-(meth)allyloxypropyl, 1-hydroxy-3-(meth)allyloxypropyl, 2-(hydroxy)-3-(ethoxy)-propyl, 3-(allyloxy)-2-(3-(allyloxy)-2-hydroxypropoxy)-propyl, vinylbenzyl, 3-(meth)acrylamidopropyl, and 2-(meth)acryloyloxy ethyl.

3 . The polymer according to claim 1 , wherein the polymerization mixture includes at least one monomer of Structure (I), wherein R 4 and R 41 are both other than H.

4 . The polymer of claim 1 , wherein the polymerization mixture includes at least one monomer of Structure (I) wherein R 4 and R 41 are both alkoxy.

5 . The polymer of claim 1 , wherein the polymerization mixture includes (a) N-(3-dimethylaminopropyl)-4-methoxy-1,8-naphthalimide, 1 or 2-hydroxy-3-(meth)allyloxypropyl quaternary salt comprising less than 5 mol % of (b)N-(3-dimethylaminopropyl)-4-methoxy-1,8-naphthalimide, based on 100 mol % of (a).

6 . The polymer of claim 5 , wherein (a) is incorporated into the polymer to the extent of at least 98%.

7 . The polymer of claim 1 , wherein the polymerization mixture includes at least one monomer of Structure (II).

8 . A method of controlling scale in a water system, the method comprising the steps of:

(a) dosing the water system with a water treatment polymer according to claim 1 ; and

(b) monitoring the fluorescent signal emitted from said industrial water system.

9 . A process of preparing the water treatment polymer according to claim 1 , the process comprising the following steps:

(a) polymerizing a polymerization mixture comprising:

(i) at least one water-soluble carboxylic acid monomer, or salt or anhydride thereof, present in an amount of 10-99.999 mol % based on 100 mol % of the polymer;

(ii) at least one quarternized naphthalimide fluorescent monomer of either (a) Structure (I) comprising less than 8 mol %, based on 100 mol % of Structure (I), of Structure (III) or (b) Structure (II) comprising less than 8 mol %, based on 100 mol % of Structure (II), of Structure (VI); and

(b) ensuring the fluorescent monomer is incorporated into the water treatment polymer to an extent equal to or greater than 90%.

10 . A fluorescent monomer suitable for use in the process of claim 9 , said monomer comprising either (a) Structure (I) comprising less than 8 mol %, based on 100 mol % of total naphthalimide fluorescent monomer, of Structure (III) or (b) Structure (II) comprising less than 8 mol %, based on 100 mol % of total naphthalimide fluorescent monomer, of Structure (VI), wherein:

Structure (I) is:

wherein

R 4 and R 41 are independently selected from H, hydroxy, alkoxy, aryloxy, arylalkoxy, alkylaryloxy, (meth)allyloxy, vinylbenzyloxy, heteroaryl, —NO 2 , C 1 -C 4 alk-O—(CHR 5 CH 2 O—) n , —CO 2 H or a salt thereof, —SO 3 H or a salt thereof, —PO 3 H 2 or a salt thereof, -alkylene-CO 2 H or a salt thereof, -alkylene-SO 3 H or a salt thereof, and -alkylene-PO 3 H 2 or a salt thereof;

n=1-10;

R 1 and R 2 are independently C 1 -C 4 alkyl;

R 3 is selected from (meth)allyl, (meth)acryl, 2-hydroxy-3-(meth)allyloxypropyl, 1-hydroxy-3-(meth)allyloxypropyl, 2-(hydroxy)-3-(ethoxy)-propyl, 3-(allyloxy)-2-(3-(allyloxy)-2-hydroxypropoxy)-propyl, vinylbenzyl, 3-(meth)acrylamidopropyl, and 2-(meth)acryloyloxy ethyl, or alkyl;

R 5 is selected from H and C 1 -C 4 alkyl;

A is selected from the group consisting of alkyl, alkoxyalkyl, alkylamidoalkyl, arylalkyl or nonexistent; with the proviso that when A is nonexistent, B is nitrogen and B is bonded directly to the imide nitrogen;

B is sulfur or nitrogen with the proviso that when B is sulfur only one of R 1 or R 2 is present; and

X − is an anionic counter ion;

Structure (II) is:

wherein

m=1-10;

R 7 and R 8 and R 9 are each independently an alkyl and may be the same or different;

R 6 is selected from the group consisting of vinyl, alkenyl, and (meth)allyl;

D is oxygen or nonexistent, with the proviso that when D is nonexistent, (CH 2 ) m is bonded directly to a carbon on the ring; and

X − is an anionic counter ion;

Structure (III) is:

wherein A, B, R 1 , R 2 , R 4 , and R 41 are as defined above; and

Structure (VI) is:

wherein D, m, R 7 -R 9 , and X − are as defined above and R 66 is H or alkyl.

11 . The monomer of claim 10 , which contains Structure (I) and less than 8 mol %, based on 100 mol % of total naphthalimide fluorescent monomer, of compounds of Structure (III).

12 . The monomer of claim 11 , which is (a)N-(3-dimethylaminopropyl)-4-methoxy-1,8-naphthalimide, 1 or 2-hydroxy-3-(meth)allyloxypropyl quaternary salt comprising less than 5 mol % of (b)N-(3-dimethylaminopropyl)-4-methoxy-1,8-naphthalimide, based on 100 mol % of (a).

13 . A fluorescent monomer suitable for use in the process of claim 9 , said monomer comprising Structure (I):

wherein

R 4 and R 41 are independently selected from H, hydroxy, and C 1 -C 4 alk-O—(CHR 5 CH 2 O) n with the proviso R 4 and R 41 are not both H; or R 4 and R 41 are both alkoxy;

n=1-10;

R 1 and R 2 are independently C 1 -C 4 alkyl;

R 3 is selected from (meth)allyl, (meth)acryl, 2-hydroxy-3-(meth)allyloxypropyl, 1-hydroxy-3-(meth)allyloxypropyl, 2-(hydroxy)-3-(ethoxy)-propyl, 3-(allyloxy)-2-(3-(allyloxy)-2-hydroxypropoxy)-propyl, vinylbenzyl, 3-(meth)acrylamidopropyl, and 2-(meth)acryloyloxy ethyl;

R 5 is selected from H and C 1 -C 4 alkyl;

A is selected from the group consisting of alkyl, alkoxyalkyl, alkylamidoalkyl, arylalkyl or nonexistent; with the proviso that when A is nonexistent, B is nitrogen and B is bonded directly to the imide nitrogen;

B is sulfur or nitrogen with the proviso that when B is sulfur only one of R 1 or R 2 is present; and

X − is an anionic counter ion.

14 . The monomer of claim 13 , which is N-(3-dimethylaminopropyl)-4-hydroxy-1,8-naphthalimide, 1 or 2-hydroxy-3-(meth)allyloxypropyl quaternary salt.

15 . The monomer of claim 13 , wherein R 4 and R 41 are both alkoxy.

16 . The monomer of claim 13 , which is a mixture of two monomers of Structure (I), a first wherein R 4 is alkoxy and R 41 is H and a second wherein R 4 and R 41 are both alkoxy.

17 . A polymer prepared by polymerizing the monomer of claim 10 with other monomers.

18 . The polymer according to claim 17 , wherein the other monomers are selected from the group consisting of cationic, anionic, and/or nonionic monomers.

19 . The polymer according to claim 17 , wherein the fluorescent monomer is incorporated into the polymer to an extent equal to or greater than 90%.

20 . A method for coagulation or flocculation in a water treatment system, the method comprising the steps of:

(a) dosing the water system with the water treatment polymer according to claim 1 ; and

(b) monitoring the fluorescent signal emitted from the water treatment system.

21 . A method for determining whether a given location has been cleaned comprising the steps of:

(a) applying the water treatment polymer according to claim 1 to the location;

(b) cleaning the location at least once; and

(c) attempting to detect the presence of the fluorescent naphthalimide derivative remaining at the location after said cleaning, which, presence, if detected, indicates that additional cleaning is needed.

22 . A method for coagulation or flocculation in a water treatment system, the method comprising the steps of:

(a) dosing the water system with the water treatment polymer according to claim 17 ; and

(b) monitoring the fluorescent signal emitted from the water treatment system.

23 . A method for determining whether a given location has been cleaned comprising the steps of:

(a) applying the water treatment polymer according to claim 17 to the location;

(b) cleaning the location at least once; and

(c) attempting to detect the presence of the fluorescent naphthalimide derivative remaining at the location after said cleaning, which, presence, if detected, indicates that additional cleaning is needed.