Thermal Analysis and Quality Control of Polyolephines

Author Name(s): Lenar N. Shafigullin, Natalia V. Romanova, Gulgena D. Shakirova
Author Email: Romanova.NV@kamaz.ru

Abstract

In the work, thermal studies of compositions based on polypropylene were carried out and, depending on the composition of the composition, a comprehensive assessment of the quality of materials of polymer automotive components was carried out, since comprehensive quality control of materials is the confidence that the finished products are of high quality, which is always maintained at the official level. Comprehensive studies of the quality of the material of automotive components products depending on the content of filler-talc and high-density polyethylene HDPE in the polypropylene composition are proposed, consisting in evaluating the thermophysical parameters of the composition and the effect of the composition on the physicomechanical properties of the finished product. It was revealed that the samples of the details of various batches differ in the composition of the polymer matrix from the initial required raw material of the PP composition. It was determined that HDPE is present in the PP composition, which can have a negative effect on the quality of finished products according to the required level of physical and mechanical characteristics. Thus, studies using differential scanning calorimetry showed that two minimums are observed in the samples of materials of automotive components products: the first of two minima (endotherm) indicates the melting of polyethylene (130-135 0C), which occurs at a lower temperature, and the second, observed at a higher temperature, corresponds to the melting of polypropylene (165-170 0C). Peak area is a measure of the relative content of components in a material. The calculation of the relative content of polyethylene and polypropylene in all studied samples of the composition details was carried out. It was found that, on average, the relative calculated value of the polyethylene content in the composition varies from 20 to 25% of the mass, and the relative calculated value of the polypropylene content in the composition is from 74 to 82% by mass. It is shown that the lack of quality of the material can be established at the stage of input control. A method for evaluating the composition of the material of products is proposed, which indicates the difference between batches of products of automotive components and can serve as a basis for accepting or rejecting this lot by conducting a sufficiently short-term DSC analysis and calculating the relative content of polyolefins in the composition.

Introduction

Polyethylene and polypropylene occupy 54% of the total world production of polymers and are the basis for the production of many composite materials, due to the diversity of their properties, determined by the synthesis of the polymer matrix and the nature of other components that make up the polymer composition [1-10]. In the auto industry from the compositions based on polyolefins, in particular, polypropylene makes the large spectrum of the components of auto-components, for example, such as the silencers of the rotary headlight, casing of air of filters, different tanks, etc One of the important factors, which determines the success of complex quality control in the production, this is confidence in the fact that the materials possess the high quality, which always remains at the official level. If they take place of the fluctuation of the indices of the properties of the source material, then this forces the processor to continuously regulate the technological process to compensate these fluctuations. So that the articles would be highquality, the obtained by production raw material must answer the specification of the customer, and the indices of his properties must be plotted in the framework of the requirements of production. Some fluctuations of properties are permitted. Thus, for instance, all parties raw material, even relating to the same stamp, and the like nevertheless slightly are differed from each other, even if they are set by the same producer and are obtained in the continuous process.

Conclusion

It is shown that the lack of quality of the material can be established at the stage of input control. A method for evaluating the composition of the material of products is proposed, which indicates the difference between batches of products of automotive components and can serve as a basis for accepting or rejecting this lot by conducting a sufficiently short-term DSC analysis and calculating the relative content of polyolefins in the composition

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