Solubility parameter (SP value) is an index of solubility. This is an application that can calculate the SP value of resin and solvent from the molecular structure. Currently, this app supports "Japanese" and "English".

The Fedors calculation method is a relatively simple and easy-to-understand calculation method among the methods for obtaining the SP value from the molecular structure.
See the references below for the data used to calculate this software. 「塗料・インクにおける溶液物性の基礎とその制御・評価」

【user manual】

◆ An example of calculation with 1-hexanol is shown below.
Hexanol is composed of one [-CH3], five [-CH2-], and one [-OH]. The density is 0.8153 g / cm³.
(1) Use the [↑] [↓] buttons to change the number of each substituent. Please fill in the density.
(2) Click the [Calculate] button to calculate the SP value.
(3) The SP value will be 16.9.

◆ An example of polypropylene (PP) calculation is shown below. For polymers, enter the molecular structure of 1 unit.
One unit of polypropylene consists of one [-CH3], one [-CH2-], and one [> CH-]. The density is 0.855 g / cm³.
(1) Use the [↑] [↓] buttons to change the number of each substituent. Please fill in the density.
(2) Click the [Calculate] button to calculate the SP value.
(3) The SP value will be 15.6.

【Application】

The SP value is also effective as an index of compatibility of high molecular polymers. When mixing two types of polymers, if the SP values are close, the compatibility is good, and if the SP values are far, a "sea island structure" is likely to occur.