Method for coating pipe segments

Patent metadata

Field	Value
Publication number	US-2015267856-A1
Application number	US-201414223181-A
Country	US
Kind code	A1
Filing date	Mar 24, 2014
Priority date	Mar 24, 2014
Publication date	Sep 24, 2015
Grant date	—

Abstract

A method for coating a segment of pipe is disclosed. The method comprises applying by electrodeposition a coating composition to the segment of pipe wherein the coating composition comprises:
(i) a (meth)acrylic polymer dispersed in aqueous medium prepared by polymerizing in the presence of a cationic salt group containing polymeric dispersant a polymerizable ethylenically unsaturated monomer composition comprising a mixture of ethylenically unsaturated monomers at least one of which contains at least two ethylenically unsaturated groups per molecule;
(ii) an electrodepositable cationic resinous vehicle containing active hydrogen groups; and
(iii) a curing agent reactive with the active hydrogen groups.

First claim

1 . A method comprising applying by electrodeposition a coating composition to the segment of pipe wherein the coating composition comprises:
(i) a (meth)acrylic polymer dispersed in aqueous dispersion medium prepared by polymerizing in the presence of a cationic salt group containing polymeric dispersant a polymerizable ethylenically unsaturated monomer composition comprising a mixture of ethylenically unsaturated monomers at least one of which contains at least two ethylenically unsaturated groups per molecule; (ii) an electrodepositable cationic resinous vehicle containing active hydrogen groups; and (iii) a curing agent reactive with the active hydrogen groups.

2 . The method of claim 1 in which the segment is a segment of pipe joining two linear sections of pipe.

3 . The method of claim 2 in which the segment is non-linear.

4 . The method of claim 3 in which the segment is elbow shape.

5 . The method of claim 1 in which the monomer containing at least two ethylenically unsaturated monomers comprises a poly(meth)acrylate.

6 . The method of claim 5 in which the poly(meth)acrylate comprises a tri- and/or tetra(meth)acrylate.

7 . The method of claim 1 in which the mixture of ethylenically unsaturated monomers comprises a (meth)acrylic monomer containing active hydrogen groups.

8 . The method of claim 1 in which the dispersion medium comprises water, organic solvent and the cationic salt group-containing polymeric dispersant that is different from the electrodepositable cationic resinous vehicle.

9 . The method of claim 1 in which the cationic salt group-containing polymeric dispersant comprises a (meth)acrylic resin.

10 . The method of claim 9 in which the cationic salt group comprises amine salt groups and/or sulfonium salt groups.

11 . The method of claim 1 in which (i) has an Mz of at least 500,000.

12 . The method of claim 1 in which (ii) comprises a (meth)acrylic polymer.

13 . The method of claim 1 in which (ii) is prepared in organic solvent and inverted into aqueous medium.

14 . The method of claim 1 wherein the coating composition is substantially free of bisphenol A and derivatives thereof.

15 . A pipe segment coated in accordance with the method of claim 1 .

16 . A pipe segment coated in accordance with the method of claim 14 .

Assignees

• Ppg Ind Ohio Inc

Inventors

• Sandala Michael
• Hsu Lorraine
• Wilson Craig

Classifications

• F16L58/1009

  the coating being placed inside the pipe · CPC title

• C09D5/4473

  Mixture of polymers · CPC title

• C09D5/4476

  comprising polymerisation in situ · CPC title

• C25D13/14

  Tubes; Rings; Hollow bodies · CPC title

• F16L58/1054

  the coating being placed outside the pipe · CPC title