STUDY OF PECULIARITIES OF THE STRUCTURE OF POLYMER - POLYMER COMPOSITES BASED ON POLYPROPYLENE

ИЗУЧЕНИЕ ОСОБЕННОСТЕЙ СТРУКТУРЫ ПОЛИМЕР–ПОЛИМЕРНЫХ КОМПОЗИТОВ НА ОСНОВЕ ПОЛИПРОПИЛЕНА

Лингерт Александр Теодорович

магистрант, кафедра НТМ, Карагандинский технический университет,

РК, г. Караганда

Набоко Елена Петровна

научный руководитель, канд. техн. наук, доц., Карагандинский технический университет,

РК, г. Караганда

ABSTRACT

The aim of this work is to study the thermal properties and study the structure of polymer-polymer composites based on polypropylene.

To achieve this goal, the following tasks were solved:

- investigation of thermophysical properties of polymer-polymer composites based on polypropylene and a copolymer of ethylene with vinyl acetate (sevilene);

- formation of the structure and processes of crystallization of mixtures;

 - study of the thermal stability of the obtained composites.

АННОТАЦИЯ

Целью данной работы являлось исследование термических свойств и изучение особенностей структуры полимер–полимерных композитов на основе полипропилена.

Для достижения поставленной цели решались следующие задачи:

- исследование теплофизических свойств полимер-полимерных композитов на основе полипропилена и сополимера этилена с винилацетатом (сэвилена);

- выявление особенностей структуры и процессов кристаллизации смесей;

- изучение термостойкости полученных композитов.

Keywords: polymer-polymer composites, polypropylene, ethylene.

Ключевые слова: полимер-полимерные композиты, полипропилен, этилен.

Studies of the thermal properties of polymers, in particular polypropylene, and their thermal degradation are of paramount importance from a scientific point of view. They not only explain the behavior of polymers under high temperature conditions and help in the selection of the most suitable type from existing materials, but, which is sometimes even more important, make it possible to predetermine the structure and synthesis routes for new materials with desired properties.

Natural and synthetic polymers have recently been widely used in new fields of science, technology and industry, where the temperatures used are much higher than usual. These materials are very often exposed to high temperatures during their processing, for example during pressing, extrusion or casting. Therefore, it is very important to know what effect heat has on polymers. From the available information, it can be seen that the molecular weight initially, when the weight loss is a few percent, falls very quickly, and then the decrease in molecular weight is slow. [1].

For the correct use of polypropylene in various fields, it is very important to know the processes of its destruction. During the thermal decomposition of polypropylene in an inert atmosphere or vacuum, the molecular weight decreases and volatile products are formed. The decrease in the molecular weight of the polymer depends on the temperature and duration of pyrolysis and is expressed by the equation:

                                                       (1)

where M is the molecular weight of PP after pyrolysis;

M₀ - is the molecular weight of the original PP sample;

g - is the mass of the sample, g;

S - is the number of links broken per minute;

N - is Avogadro's number;

T - is the duration of pyrolysis, min.

The literature provides the following S/g 10^-17 : [2].

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