Computer Chemistry Consultancy - XML4Pharma, Katzelbachweg 18, A-8052 Thal, Austria,

Calculation of Hoy Solubility Parameters

Example of a killer application

In the past, an applet was constructed for a major Chemical/Coatings company. This applet predicts the well-known Hoy Solubility Parameter for organic compounds and polymers. All the "science" was embedded in the applet.

Before this applet was constructed, only a few specialists within the company had access to this technology, so the technology was not generally available to all researchers. This not only meant that it could take days before a calculation was performed by the specialist on request of a researcher, but also that many researchers were even unaware of the existence of the technology, so that they simply didn't use it.

After this technology was made available on the corporate intranet of the company, many more researchers started using the technology. It led to an enormous increase in efficiency, as it now became possible to predict, not only whether a new resin/polymer would be soluble in a certain solvent, but also to predict which solvents were most suitable for the resin/polymer. Before the applet was available on the intranet, it happened many times that a resin was developed (taking some 2-5 man-weeks of work) and then it was found that it was not soluble at all in the envisaged solvent !

For the BU involved, this intranet tool was really a killer application. The word spread, and more and more researchers of other BU's started to use the tool too, so that after a few months, the number of users had increased to several hundreds, whereas before the start of the project, only about 3-4 people had access to the technology.

How the applet works

The Hoy method of calculating Solubility Parameters is essentially a "group contribution method". This means that for each chemical group there is a contribution to 3 independend parts of the solubility parameter (the nonpolar or dispersive part, the polar part and the hydrogen bond part), with corrections for rings, aromaticity, cis- or trans-, etc..
The applet has an input screen (very user-friendly) for entering the chemical information, using buttons and number input fields. On pressing the "Calculate" button the solubility parameter is calculated and given in sqrt(cal/cm3) as well as sqrt(J/cm3).

If the "Search Best Solvents" button is clicked, the applets loads a little database with over 750 solvents and sorts the solvents according to their compability with the compound for which the Solubility Parameter was calculated. It displays the result in an interactive table. The compounds in these table can then be sorted in several ways, e.g. on basis of density, boiling point, vapor pressure, relative evaporation rate, etc..

If you want to know more about or try out this applet, contact us, so that we can make it available through the internet for a limited amount of time (for test purposes only - not for production).

Future Developments - Customization

On your request, we can modify/extend this applet further. For example, for a PVC-additives producing company, we adapted the applet so that it automatically calculates the compability with PVC. Also there it became a killer application: before the tool was available, only experiment made it clear whether a new compound was suitable as e.g. a softener in PVC. The tool made it possible to limit the number of compounds to be synthesized considerably, saving large amounts of money, and shortening the time-to-market.
We can also interface the applet with your company's solvents/materials database, so that it calculates the compability with solvents/materials from this database.

Why an applet ?

Why did we make this tool available as an applet? Why not make an interface to a program on the server and do all the calculations on the server ? Well, this is simply a matter of consideration. An applet loads slower, but it has the advantage that traffic is limited to this (once-only) loading. If the program runs on the server, the web page has to be refreshed to give the results, which also takes some time. Especially if the user performs several calculations, the longer loading time for the applet is easily compensated by the fact that no reloading to show each result is necessary.
This example shows, that in the design of an application, the future amount of use of an application has already to be taken into account, in order to get optimal performance of the application.


See our products page for the availability of this software.

Computer Chemistry Consultancy, June 2001