[MSUTIMO]

Dear all;

    I have a hard time understanding this paragraph

A prescribed amount of the PZT powder was added to a 30 wt% epoxy solution in a mixed solvent of xylene and isobutyl alcohol (80/20 by weight), and was stirred for 30 min in a Red Devil paint shaker, thus obtaining a so-called pigment paste having the PZT/epoxy composition of 92/8 by weight. To this pigment paste, a 30 wt% epoxy solution containing a prescribed amount of the epoxy hardener was added with stirring until the PZT/epoxy composition became 88/12 by weight (53/47 by volume) in the final paint. The amount of the epoxy hardener was prescribed in such a way that the ratio of the active hydrogen of the hardener to the epoxide group of the epoxy resin was 1:1 by mol in the final paint.

This paragraph is talking about the procedure for mixing some chemical product in order to get a piezoelectric paint:
the products are:

1- PZT powder
2-Epoxy
3-Xylene
4-Isobutyl
5-hardner

The description of the mixture is not clear, can some one help me to understand it with more details. I would appreciate if someone give me in steps and if possible quantities the authors used in the paragraph. What is the solute? what is the solvent? how to get the 30wt%?

Thank you so much

[MSUTIMO]

    

No replies..
is it that hard for chemical engineers?

[AWK]

Explanation of all these terms you can find through GOOGLE or WIKIPEDIA

[MSUTIMO]

Thanks  AWK for the suggestion, but my problem it`s not about finding explanations of all the terms rather it is about what are the steps the author followed in mixing the products:

Let me reformulate my question: what are here the solutes, solvents, and how the author got the 92/8 by weight?

Example:

He mixed 30wt% epoxy solution in a mixed (xylene -isobutyl). Does that means he weighted let`s say 30 grams of epoxy and 70 grams of (xylene -isobutyl)  to get a 100 grams of a solution for which he added an amount of PZT powder?
My real problem is that i am trying to do the same thing, but i dont know how much i should weight from  each product.

Thankx

[AWK]

30 wt% epoxy solution in a mixed solvent of xylene and isobutyl alcohol (80/20 by weight)

30 grams of epoxy resin + 56 grams of xylene + 14 grams of isobutyl alcohol (or 70 g of this mixture)
To obtain 92/8 ratio you should add (30/8)x92=345 g of PZT for each 100 g od solution.

[MSUTIMO]

Thx AWK, i really apreciate, one more thing if you don`t mind.

what the author means by "The amount of the epoxy hardener was prescribed in such a way that the ratio of the active hydrogen of the hardener to the epoxide group of the epoxy resin was 1:1 by mol in the final paint".


Thank you again for you great help