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Purpose. Investigate the attenuation of ultrasonic waves for non-contact control of composite materials. Methodology. In this work non-contact ultrasonic method of control of thickness of the polymer coating of textile materials is used, this method considers the attenuation of ultrasonic waves. Findings. Attenuation of ultrasonic signal for most fabrics can be neglected in comparison with the attenuation in a polymer coating and that is proved. Results researches of influence of thickness of polymer coating and fabric on attenuation of ultrasonic signal are resulted. Originality. In article considered dependences of amplitudes of ultrasonic waves, one of them, that passing through the polymer coating, other of them, that passing through the fabric, and other waves, that reflecting from the polymer coating and from the fabric, with attenuation. Practical value. Optimal frequency of ultrasonic waves to decreasing attenuation of signal for non-contact control of thickness of the polymer coating was suggested. [ABSTRACT FROM AUTHOR]

Purpose: Investigation of physical and chemical conversions and reactions in extrusion processing of polyester polymer blends. Methodology: Melt flow index, extensional and impact mechanical testing, reactive extrusion methods were used. Findings: For polymer blend PET with PC melt intermolecular reaction was carried out and changes in rheological and mechanical properties was investigated in accordance with reactions rate and experimental conditions. Influence of different type of additives for reaction rate was evaluated, activating and inhibiting action was find. Intermolecular reactions in the melt are confirmed by partial dissolution and changes in rheological properties of the blends with dependents to reaction time and temperature. During intermolecular reaction evidence of melt foaming was find after extend of some reaction time. Originality: The influence of different additive and process conditions on reaction rate was investigated. Practical Value: Practical aspects of polyester blend processing on extrusion equipment. [ABSTRACT FROM AUTHOR]