Computer Program for Designing Polymers

For more than thirty years Dr. Akadski from the Institute of Element-Organic Substances of RAS with his colleagues had developed methods of polymer materials properties calculation. At last he has achieved success. A computer program for polymer structure building was created and actively used for the construction of new types of materials.

The software solves both the direct task -- determining properties by examining a material's structure -- and the inverse task -- taking a set of properties and returning a set of corresponding substances. The program can propose thousands of substances with necessary properties. To limit this number, a researcher can specify a set of initial substances from which he wants to receive a necessary polymer, and the computer will propose a subset of variants. The results of the calculations are in good agreement with experiments.

While inputting data, the researcher constructs the polymer on a screen. The programmer uses individual atoms, not atom groups, so he can construct almost any structure he wishes. If the structure is reasonable one, the program will calculate the values of more than 60 parameters (for instance, temperature of vitrification, density, dielectric coefficient, etc.). It is possible to see the dependence of one parameter on the other. Moreover, there is an option to predict polymer compatibility and solubility in organic substances. Besides ordinary polymers, the program can operate with cross-linked polymers.

Using this program, the scientists have created gradient polymers: the elasticity of these materials is different in various areas of a unit. For example, in a rod-like unit one end is as hard as plastic and the other is as soft as rubber. The polymer network structure of such gradient materials is very unusual. Its large sites are linked by very short and flexible chains that lead to a tapering of properties. The program helped to compute how to change the structure of the polymer for grading its modulus of elasticity. A unit is obtained absolutely elastic and resizes after deformation. "We can make with gradient elasticity polymers, for example, props for any technical equipment. Such props will be soft from below to not scratch the table or the floor and hard at the top. Dental prosthesis from such materials are very useful. They must be soft at the top to not injure the gum and hard from below to gnaw nuts", said Dr. Akadsky

Russian Science News Service, Moscow
+095 267-54-18, chelife@glas.apc.org

Original Russian article will issue from the magazine "CHEMISTRY AND LIFE - XXI CENTURY" 1999, 9

For further information, contact:
Dr. Akadsky A.A., Polymer materials laboratory of Element-organic Substances Institute of Russian Academy of Sciences, Moscow, (095) 135-93-98, andrey@ineos.as.ru