Wyniki wyszukiwania - Biblioteka Nauki

1

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

100%

Barszczewska-Rybarek I.

Polimery

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2008

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tom T. 53, nr 3

190-194

PL

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.

EN

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.

2

Calorimetric study of thermally-activated polymerization of urethane-dimethacrylate monomers

100%

Barszczewska-Rybarek I.

Polish Journal of Applied Chemistry

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2009

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tom Vol. 53, nr 2

117-122

EN

The thermally activated curing behaviour of a series of urethane-dimethacrylates, derived from dicarbamatcs of oligocthylcne glycols monomethacrylates and aliphatic, cycloaliphatic and aromatic diisocyanates, were examined by differential scanning calorimetry (DSC). The effect of monomer structure on the onset (T") and peak temperatures (Tp), the degree of double bonds conversion (DC) and the activation energy (Ea) were studied. A distinct dependence of the molar mass and chemical structure of the monomer on the above parameters is seen from the collected data.

3

Calorimetric study of polymerisation of dimethacrylate monomers

63%

Barszczewska-Rybarek I. , Gibas M.

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2001

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tom z. 146

55-58

EN

The new urethane-dimethacrylates were examined by Differential Scanning Calorimetry (DSC) in order to evaluate conversion of double bonds and then the network parameter values of the polymer networks formed. The latter were calculated for: ideal Flory network, non-ideal network with tetrafunctional junction points and non-ideal network with trifunctional junction points to compare with DMTA results.

4

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

51%

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

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2015

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tom Vol. 17, no. 3

13--22

EN

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.

5

Nowe monomery, makromonomery i polimery metakrylanowe

51%

Gibas M. , Barszczewska-Rybarek I. , Korytkowska-Wałach A.

Przemysł Chemiczny

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2005

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tom T. 84, nr 6

402-404

PL

Przedstawiono w zarysie możliwości syntezy kilku nowych monomerów i makromonomerów metakrylanowych. Produkty te oraz ich polimery scharakteryzowano przy pomocy NMR, GPC, ESI-MS i DMTA. Otrzymane materiały mogą być użyteczne dla medycyny, szczególnie dentystyki oraz w zastosowaniach technicznych.

EN

New monomers of the urethane-dimethylacrylate type were prepd. Their dicarbamate structures differed in diisocyanate-derived central units and in the length of the methacrylate group-terminated oligooxyethylene chains. Poly(urethane-dimethacrylates) prepd. thermally (benzoyl peroxide) or photochemically (camphorquinone–N,N-dimethylaminoethyl methacrylate) at room temp., ranged from hard and stiff to soft and elastic; their glass transition temps. varied with the no. of oxyethylenic units. Macromonomers were prepd. by NaH- or t-BuOK-catalyzed step-growth polyaddition of glycol monomethacrylates. Adhesive monomers were prepd. from oligoethylene glycol monomethacrylates and pyromellitic anhydride. The new materials are believed to be applicable in dentistry, medicine and technology.