Home /
T.O.C.
FAQs
 
Good
Books
Ref.
Libr.
Advertise
Here
Help
Wanted
Current
Q&A's
Search 🔍
the Site

Problem? Solution? Chime right in!
(perhaps the world's last 'no registration' site)

-----

"How to obtain a PUD [Polyurethane Dispersion?]"



November 14, 2016

Q. I have trying to stabilize a 2k-PU paint so I can use it for plating jewelry. I have used the following procedure:

- mix the 2k PU paint;
- dilute it by 20%;
- add acetic acid to disperse the PU;
- lastly, add water (about 80%).

However, 1 day after mixing it, the PU does not remain in suspension. It sediments and forms a kind of ball. Please, can anyone give me clue on what to do?

Walter Okpala
Plating shop employee - São Paulo,Brazil
^


November 2016

Hi Walter. Sorry but I'm not familiar with this. Are you suggesting that you believe that you can make a proper solution for CED electrocoating by dispersing reacted polyurethane into a solution of acetic acid and water?

Regards,

pic of Ted Mooney
Ted Mooney, P.E. RET
Aloha -- an idea worth spreading
finishing.com - Pine Beach, New Jersey
^


November 14, 2016

Q. Thank you for your quick response. As I said in my first question. I did the following:

(1) mixed the 2k-PU paint;

(2) diluted the 2k-PU by 20%;

(3) obtained the PU dispersion by adding 3% by volume of acetic acid as recommended in books;

(4) finally adding water (80% by volume) and mix it thoroughly so the dispersed PU can remain in suspension.

However, the PU dispersion did not remain in suspension for a long time. After 1 day, it started forming a kind o ball. I do not what to do to keep it in suspension before coating. Is there a special additive to be used for that purpose?

Walter Okpala
- São Paulo, Brazil
^

none
finishing.com is made possible by ...
this text gets replaced with bannerText
spacer gets replaced with bannerImages

Q, A, or Comment on THIS thread SEARCH for Threads about ... My Topic Not Found: Start NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact    -    Privacy Policy    -    ©1995-2021 finishing.com, Pine Beach, New Jersey, USA