Abstract
Currently, methods for predicting the properties of polymers are very popular, since they simplify the work of synthetic chemists. Instead of lengthy and time-consuming experiments, many properties of polymers can be predicted in advance based on their chemical structure. Naturally, such tasks must be computerized so that the properties are predicted after the chemical structure of the repeating polymer unit is displayed on the display screen. This is the so-called direct task. The inverse problem is more complex and interesting. It consists in entering the intervals of the desired characteristics into the computer. Then computer synthesis of polymers possessing these characteristics are realized. The work consists in writing a computer program that allows the computer synthesis of polymers of different classes with specified intervals of water permeability. These classes include polyurethanes, polysulfones, polysulfides, polyethers and polyesters, polyamides, polyketones and polyethyrketones, polycarbonates, polyolefins, vinyl polymers, polystyrene, acrylic and methacrylic polymers. On the basis of this program, water permeability compatibility diagrams are constructed with various physical characteristics of polymers – glass transition temperature, temperature of the onset of intensive thermal degradation, cohesion energy, density, solubility parameter (Hildebrand parameter).
Highlights
Materials used in the construction industry often require polymers that possess a combination of a number of properties
Our work is devoted to constructing compatibility diagrams of the water permeability of polymers with such physical characteristics as the glass transition temperature, the temperature of the onset of intensive degradation, and the cohesion energy
For polymer materials for construction purposes, polymers with very low water permeability are of interest, if they are designed to work in outdoor conditions of a humid environment
Summary
Materials used in the construction industry often require polymers that possess a combination of a number of properties. For exterior finishing materials, a combination of low water permeability and high glass transition temperature (softening) is required. This is necessary so that the material does not pass into a rubbery state and changes its shape when heated, but remains solid while maintaining its shape. The compatibility diagram contains a very large (many thousands) number of points inside some area that is outlined. If there are points inside this region, the existence of polymers with coordinates X1 and X2, Y1 and Y2 is possible (case I). If the points with coordinates X'1 and X'2, Y'1 and Y'2 are outside this region, polymers with the given values Y'1 and Y'2 do not exist (case II)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have