В ПНИПУ изучили, как высокие температуры влияют на разрушение медицинских полимеров.

The article was published in The International Journal of Advanced Manufacturing Technology. The research was conducted as part of a government assignment from the Ministry of Education and Science of Russia for fundamental scientific investigations.

Polyetheretherketone (PEEK) and polylactic acid (PLA) materials are widely utilized in the production of medical instruments due to their biocompatibility and high mechanical strength. PEEK boasts a high melting point (300 °C) and effectively replaces metallic implants, while PLA is well-suited for 3D printing and is sourced from renewable resources such as corn starch and sugarcane, making this biodegradable polymer both cost-effective and environmentally friendly.

Researchers at Perm Polytechnic University conducted a series of experiments to investigate the degradation processes of PEEK and PLA, as well as the substances that may accelerate this degradation. The scientists printed a series of samples using a 3D printer made from polyetheretherketone and polylactic acid, and subsequently submerged them in various liquid environments – a sodium chloride solution and distilled water. Elevated temperatures of 45 °C and 70 °C were used to expedite degradation. Observations were made over a period of one to seven days, after which tensile tests were performed on the samples to evaluate their mechanical properties and strength based on the duration of exposure to the liquids.

“The degradation of PLA samples in distilled water at 70 °C occurred rapidly. The strength of the material dropped sharply on the very first day of the experiment, and by the fifth day, tensile testing became impossible as the samples had become too brittle. In contrast, this was not observed in the samples immersed in the sodium chloride solution at the same temperature, although gradual material breakdown was noted there as well,” explains Mikhail Tashkinov, head of the research laboratory "Mechanics of Biocompatible Materials and Devices" at PNIPU, PhD in Physical and Mathematical Sciences.

“The PEEK samples proved to be significantly more resistant to the degrading effects of both liquids. Over the course of a week at 70 °C, their properties remained virtually unchanged, with deviations not exceeding two percent. This can be attributed to the polymer's higher melting point,” clarifies Ilya Vindokurov, junior researcher at the "Mechanics of Biocompatible Materials and Devices" research laboratory at PNIPU.

The study conducted by the researchers at Perm Polytechnic University demonstrated that the PEEK and PLA polymers exhibit different levels of degradation resistance depending on temperature and liquid exposure. The findings will aid in developing recommendations for the use and sterilization of medical instruments to ensure their durability and safety.