Poly(urea-urethane)s (PUUR), wherein the polyol substrates of petrochemical origin, partly replaced by vegetable polyols, were synthesized. Various contents of polyols derived from rapeseed oil-from 0 to 50 wt % were used. In order to determine the chemical structure of the obtained samples, they were examined using Fourier transform infrared spectroscopy (FT-IR). Physicochemical and mechanical properties were determined using, among others, methods of differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA), as well as the tribological tests were performed. Studies have shown that new material obtained using the highest content of the polyol of vegetable origin (50 wt %) was characterized by the best storage modulus and friction coefficient. This material can be applied where low abrasive wear and volume resistivity is required.

Selected mechanical and biological properties of biodegradable elastomeric poly(ester-carbonate-urea-urethane)s (PECUUs) point towards their potential to be applied as scaffolds in tissue engineering. Here we explore their medical applicability taking into account their hemocompatibility and cytotoxicity. The influence of the ester monomer (derivatives of adipic and succinic acids), as well as diisocyanate type (IPDI and HDI) on the investigated PECUUs properties is presented. The presence of aliphatic diisocyanates, cyclic IPDI or linear HDI, governs the adhesion of Candida cells to these polymers offering the possibility to control the biofilm formation on their surface. In comparison to the linear form, cyclic diisocyanates with pentamethylene succinate or adipate fragments had two to three times lower biofilm mass formation on their surface. Reduced hemoglobin release from red blood cells observed during incubation of tested polymers with human erythrocytes suspension indicates their potential biocompatibility with human tissues. PECUUs were also able to support the growth of human keratinocytes HaCaT on their surface when coated with collagen. In effect, IPDI derivatives might possess a high potential for use in biomedical applications.

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Fretting and fretting-corrosion processes in elements of kinematic pairs used for medical applications are observed in metallic orthopedic implants, dental prosthetics elements, and orthodontic appliances. In most cases, the degradation of biomaterials significantly limits their useful life and the comfort of patients. The products formed as a result of wear may lead to poisoning of the body and the occurrence of inflammatory states, which often results in the failure of medical therapy. Fretting-corrosion processes are being paid more and more attention, although there is not much data concerning the stomatognathic system. This article presents the results of fretting-corrosion studies of one of the most frequently used metallic biomaterials, CoCrMo cobalt alloy, in the presence of human saliva and its substitutes. The results of studies indicate that friction has a large influence on corrosion processes (fretting-corrosion). Artificial saliva compositions with favorable tribological and anti-corrosion properties were successfully developed and may find applications in the stomatognathic system, e.g. for the purpose of reducing the unfavorable effects of bruxism. Fretting-corrosion studies were performed using a self-designed original device. The obtained results of studies are of great significance in scientific and applicatory terms.

Otrzymano seriê poli(wêglanouretanów), o zawartooeci 30, 34 i 45 % mas. segmentów sztywnych, z diizocyjanianu 4,4'-dicykloheksylometanu (HMDI) i oligowêglanodiolu. Scharakteryzowano w³aoeciwooeci oraz strukturê wytworzonych poli(wêglanouretanów) za pomoc¹ spektroskopii w podczerwieni FT-IR, ró¿nicowej kalorymetrii skaningowej (DSC), analizy dynamicznych w³aoeciwooeci mechanicznych (DMA), analizy termograwimetrycznej (TGA) oraz skaningowej mikroskopii elektronowej (SEM). Oceniono równie¿ w³aoeciwooeci wytrzyma³ooeciowe, odpornooeae na zu¿ycie oecierne, a tak¿e wykonano testy tribologiczne, oznaczono twardooeae, elastycznooeae przy odbiciu, gêstooeae i k¹t zwil¿ania oraz obliczono swobodn¹ energiê powierzchniow¹. Przeprowadzono wstêpne badania biologiczne, okreoela-j¹ce toksycznooeae opracowanych materia³ów. Wybrane próbki otrzymanych materia³ów testowano na symulatorze segmentu ruchowego krêgos³upa. Wytworzony implant kr¹¿ka miêdzykrêgowego po 3 mln cykli nie wykazywa³ oeladów niszczenia spowodowanego u¿yciem oeciernym i nie zmieni³ swojej charakterystyki wytrzyma³ooeciowej.S³owa kluczowe: poli(wêglanouretan), synteza, charakterystyka poliuretanów, kr¹¿ek miêdzykrêgowy. Effect of the content of rigid segments on the properties of polycarbonate urethanes for use in intervertebral disc implantsAbstract: A series of polycarbonate urethanes (PUR) containing 30, 34 and 45 wt % hard segments was synthesized from oligocarbonate diol (OCD) and dicyclohexylmethane 4,4'-diisocyanate (HMDI). The structure and properties of the obtained polymers were characterized using infrared spectroscopy with Fourier transformation (FT-IR), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMA), thermogravimetric analysis (TGA) and scanning electron microscopy (SEM). The tensile strength properties, hardness, resilience and density of PUR were determined and abrasive wear resistance was evaluated in a tribological test. The surface properties were examined using contact angle measurements and free surface energy was calculated. The preliminary cytotoxicity tests were performed. The selected samples of the obtained materials were tested using the simulator of spine motion segment. The intervertebral disc implant produced from polycarbonate urethane with 34 wt % hard segments showed no signs of decay caused by abrasion wear and did not change its mechanical characteristics after 3 million cycles.