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The novel semi-biodegradable interpenetrating polymer networks based on urethane-dimethacrylate and epoxy-polyester components as alternative biomaterials

Barszczewska-Rybarek I., Jaszcz K., Jurczyk S., Chladek G

Acta of Bioengineering and Biomechanics

2015

Vol. 17, no. 3

13--22

Purpose: This paper presents the pilot study aimed at the development of new full interpenetrating polymer networks based on urethane-dimethacrylate and biodegradable epoxy-polyester as the proposition of new biomaterials with gradually emerging porosity. Methods: The urethane-dimethacrylate monomer was obtained from 4,4’-methylenebis(phenyl isocyanate) and tetraethylene glycol monomethacrylate. The redox-initiating system was employed for its radical polymerization. The epoxy-polyester was produced by oxidation of the polyester, synthesized from succinic anhydride and allyl glicydyl ether. It was cured in a step-growth process with biogenic, aliphatic amine – spermidine. The mixtures of both monomers with adequate curing agents were room temperature polymerized. The hardened materials were characterized for damping behavior and dynamic modulus, hardness, water sorption, the course of hydrolytic degradation as well as the morphology – before and during the degradation process. Results: The cured materials revealed the nonporous, dense morphology. In the hydrolytic environment, the epoxy-polyester network degraded and the porous urethane-dimethacrylate scaffold remained. The epoxy-polyester appeared to prevent the urethane-dimethacrylate from attaining a high degree of conversion, even if the polymerization rate and the molecular mobility of the latter one are higher than those of the epoxy-polyester. The most homogeneous material with the best physico-mechanical properties was obtained when the urethane-dimethacrylate content was smaller than the epoxy-polyester content, respectively 25 and 50 wt%. Conclusions: The system presented in this work could be useful in tissue engineering, where at the beginning of the tissue regeneration process it would meet the implant mechanical properties and then would deliver its porosity, facilitating the tissue regeneration process.

Badanie wpływu struktury uretano-dimetakrylanów na morfologię i właściwości otrzymywanych z nich polimerów

Barszczewska-Rybarek I.

Polimery

2008

T. 53, nr 3

190-194

monometakrylanów glikoli: mono-, di-, tri- i tetraetylenowego oraz diizocyjanianów: heksametylenu (HMDI), 4,4'-dicykloheksylometylenu (CHMDI) i 4,4'-difenylometylenu (MDI), zsyntezowano monomery, z których w procesie fotopolimeryzacji otrzymano trzy szeregi homologiczne poli(uretano-dimetakrylanów) [poli(UDMA)]. Zbadano wpływ budowy chemicznej monomerów na wybrane właściwości mechaniczne (dynamiczny moduł sprężystości podłużnej i twardość Brinella) oraz morfologię tych polimerów. Morfologię badano za pomocą mikroskopii sił atomowych (AFM) i rentgenografii proszkowej (XRPD). XRPD wykorzystano do ilościowego opisu niejednorodności sieci poli(UDMA). Wyniki badań wskazują, że właściwości mechaniczne poli(UDMA) zależą od budowy chemicznej monomerów, konwersji wiązań podwójnych oraz wymiarów obszarów uporządkowanych.

The monomers were synthesized from monomethacrylates of glycols: mono-, di-, tri or tetraethylene one and diisocyanates: hexamethylene diisocyanate (HMDI), 4,4'-methylenebis(cyclohexyl isocyanate) (CHMDI) or 4,4'-methylenebis(phenyl isocyanate) (MDI) (Scheme A). Three homologous series of poly(urethane-dimethylacrylate) polymers [poly(UDMA)] were obtained by photopolymerization of these monomers. The effect of monomers chemical structure on selected mechanical properties (dynamic elastic modulus, Brinell hardness) and on morphology of the polymers obtained were investigated (Fig. 1-3). Polymer morphology was studied by atomic force microscopy (AFM) and X-ray powder diffraction (XRPD) methods (Fig. 4 and 5). XRPD method was used for quantitative description of poly(UDMA) network's heterogeneity (Fig. 6). The results show that mechanical properties of poly(UDMA) depend on monomer chemical structure, double bond conversion and dimensions of ordered zones.