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In the paper, we demonstrate a series of azobenzene polyimides with azomoieties located in the main chain for potential applications as membranes for controlled gas separation. Since azobenzene derivatives can exist in two forms, that is, thermodynamically stable trans and photoinduced cis, both isomers can be utilized for membrane preparation. The long term stability of the cis form is a precondition for such an application. Thus, the effect of polymer structure on the stability of cis-trans isomerization process in polymer films was investigated. The prepared azopolymers exhibited high stability of cis isomers and the return cis-trans reaction was not completed during 7 days after switching off the excitation light (405 nm). The stability of the cis-trans isomerization was discussed in the context of the fragility parameter. To the best of our knowledge, it is the first time when the main chain azopolymer was tested as a membrane for the gas separation. Two types of azomembranes, that is, bearing azobenzene derivatives as trans, and cis isomers and a reference membrane without azochromophore were prepared. Our investigations showed that the presence of trans-azomoieties increases the permeability of the gases (N2, O2, He and CO2) in comparison to the reference polyimide and that the permeability increase is not accompanied by any losses of the selectivity.

Nonwoven polymeric materials for urological applications have been prepared from different kinds of polymers: poly(glycolide-ɛ-caprolactone) (PGCL) and poly( d , l -lactide-co-glycolide) (PLGA) with the use of electrospinning technique. In order to modify properties of the electrospun nonwovens, the mixture of PGCL and PLGA have been additionally prepared. The aim of this modification was to obtain materials with intermediated properties. Additionally, diastolic drug was incorporated into the polymeric matrix in order to achieve enhanced functionality. It appeared that selected copolymers enriched with diastolic drug possess excellent fiber-forming ability. Moreover, by this incorporation, drug delivery systems for local administration for urological purposes have been obtained. The idea of local administration of a drug is highly desirable. It provides the possibility of reducing the drug dose and might enhance the efficiency of the therapy. For all nonwoven materials burst release of papaverine was observed, what was desired and expected result. This study is based on our experience with various drug delivery systems intended for different therapies. The obtained results indicate high potential of the developed polyester-based nonwovens for urological applications and local release of incorporated drug. As the possibility of designing proper, nonwoven, polyester-based materials have been confirmed, it is planned to expand range of incorporated drugs, so as to obtain various biodegradable systems for urological applications.

To the best of our knowledge, for the first time the effect of the presence of pyridine vs benzene structure in azochromophore on thermally driven cis-trans isomerization in a solid state is presented. The influence of the molar mass of the polymer matrix, in which the chromophores were molecularly dispersed, was revealed. The poly(etherimide) with a weight-average molecular weight within the range of 2 600–33 300 g/mol was applied as a matrix. The fragility parameter of the matrices was discussed also in the context of observed relationship between cis-trans isomerization in various matrixes. Additionally, thermal back reaction from the cis to the trans-form of 4-[4-(6-hydroxyhexyloxy)phenylazo]pyridine and 4-[4-(6-hydroxyhexyloxy)phenylazo]benzene in DMF solution was investigated. The holographic grating recording was realized in the poly(etherimide) containing azopyridine of different content.

The comprehensive investigations including the influence of architecture, intra– and intermolecular interactions and backbone conformation on the glass transition activation energy and the temperature dependence of segmental relaxation (fragility) in a series (azo)polyimides are presented. The studies were carried out using DSC measurements. To understand the microscopic parameters that control the glass transition phenomenon the activation energy was calculated using two different approaches, i.e., Kissinger and Moynihan models. The behavior of polyimides near the glass transition was investigated in the context of formation intra- and intermolecular H-bonds, which impact on rigidity and conformation of main and side chains of the polymers. Presence of the H-bonds was confirmed experimentally by 1H NMR and FTIR spectroscopes and theoretically by DFT simulations. Our investigations showed, that the presence of intra- and intermolecular interactions cause different conformations of the polymer chain, what may be the key to solve the puzzle of fragility parameter of polymers.

This paper presents ex-ante examination of advanced polymer materials to detect defects and define and minimize the potential failure of novel polymer products before they arise. The effect of build directions on the properties of dumbbell-shaped specimens obtained by three-dimensional printing from polylactide and polylactide/polyhydroxyalkanoate commercial filaments was investigated, as well as the hydrolytic degradation of these specimens at 50 °C and 70 °C. Taking into account previous studies, we have found further dependences of the properties of 3D printed species before and during abiotic degradation from the orientation of printing. The initial assumption that only the contact time with the 3D printer platform leads to an increase in the crystalline phase during printing turned out to be insufficient. Further investigations of individual parts of the dumbbell-shaped specimens showed that the size of the specimens' surface in contact with the platform also affected the structural ordering of the material.

Biodegradable coatings containing caprolactone units additionally enriched with ciprofloxacin formed on Ti6Al4V alloys have been developed. The polymer coatings were investigated as a carrier for ciprofloxacin-antibacterial drug. Coatings have been obtained according to the dip-coating method. Two kinds of polymers containing caprolactone units have been used: poly(glycolide-ɛ-caprolactone) and poly(glycolide-ɛ-caprolactone- d , l -lactide). The properties of the layered metal/polymer + drug system have been presented and the influence of the kind of polymer on the drug release has been evaluated. Different types of drug release profile depend on the type of used system. The CFX release from poly(glycolide-ɛ-caprolactone) is uniform with one stage, contrary to poly(glycolide-ɛ-caprolactone- d , l -lactide). The mechanism of ciprofloxacin release from GCap and GCapL matrices is different. The release from GCap and GCapL matrix fit to the Peppas-Sahlin and Korsmeyer-Peppas model, respectively. The release exponent indicates anomalous transport for GCap and case II transport for GCapL.

The use of biobased plastics is of great importance for many applications. Blending thermoplastic polylactide (PLA) with polyhydroxyalkanoate (PHA) enables the formulation of a more mechanically powerful material and this enables tailored biodegradation properties. In this study we demonstrate the 3D printing of a PLA/PHA blend as a potential candidate for biocompatible material applications. The filament for 3D printing consisted of PHA, which contains predominantly 3-hydroxybutyrate units and a small amount of 3-hydroxyvalerate units, as revealed by multistage mass spectrometry (ESI-MSn). This research found that the properties of 3D printed species before and during abiotic degradation are dependent on printing orientation. Furthermore, the 3D printed specimens exhibited good biocompatibility with HEK293 cells, indicating real promise as biological scaffolds for tissue engineering applications.

Metallic implants are very popular and frequently used. However, the implantation procedure is often associated with accompanying infections. To reduce this problem mono- and multi-drug loaded biodegradable poly(lactide-trimethylene carbonate) P(L/TMC) coatings have been developed. Three antibiotics were chosen for that purpose: azithromycin dihydrate (AZT), fusidic acid (FA) and ciprofloxacin (CFX). Popular titanium alloy, Ti6Al7Nb was used as a metal substrate. Since regular degradation process is very advantageous for medical applications, drug delivery systems were characterized during degradation. The 20% weight loss was detected after 4 weeks and this effect was similar for all samples. NMR analysis indicated stable course of degradation that was characterized by the similar content of the comonomer unit in the polymer chain at every stage of degradation. The addition of ciprofloxacin and fusidic acid molecules caused changes in thermal properties: drug molecules acted as nucleating agents and introduced changes in the crystallinity of the matrices. Changes of thermal properties were also observed during degradation. Endothermic peak corresponding to CFX or FA gradually decreased on DSC curves with the degradation time. Antibacterial activity was confirmed towards Staphylococcus aureus (methicillin sensitive and methicillin resistant) and Staphylococcus epidermidis strains (biofilm-forming and without ability to form biofilm) in the case of P(L/TMC) + CFX, P(L/TMC) + FA. The P(L/TMC) + AZT did not show antibacterial activity towards methicillin resistant Staphylococcus aureus strain and biofilm-forming Staphylococcus epidermidis. Combining ciprofloxacin, fusidic acid and azithromycin into one biodegradable coating did not enhance the antibacterial effect. The drug-free P(L/TMC) coatings did not show the eradication activity, which confirms that the antibacterial effect was caused exclusively by the released drug. Local release of the drug allows to eliminate systemic administration and significantly reduce the drug dose. It might also improve effectiveness of the treatment by the high concentration of the drug at the implantation site. Biodegradable coatings on commonly used metallic implants can be promising solution for prophylaxis of nosocomial infections since they can act as drug delivery systems releasing the antibiotics.

Three (two novel) conjugated, thiophene phenylene based polyazomethines have been obtained parallel, by chemical vapour deposition (CVD) and by chemical synthesis. They were subsequently identified and characterised by an X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry and detailed UV–Vis-NIR spectroscopy. Absorption spectra of the polymers' solutions and thin films have been examined. The spectra of polyazomethines without, with methoxy and with octyloxy side chains attached to the polymer backbone showed a conjugation-improving effect of alkyloxy side chain introduction. A comparison of spectra of the same polyazomethine's thin films deposited separately by spin-on and CVD methods revealed decrease in conjugation of compounds obtained during CVD. Additionally, amorphous character of the investigated thin films allowed to calculate the absorption edge parameters, in a way typical for amorphous semiconductor and to discuss their values in the context of chemical structure and deposition method. Surface imaging with atomic force microscope revealed different character of thin films deposited by spin-on and CVD methods.

The main objective of the presented research was to synthesise biodegradable aliphatic polycarbonates containing reactive carboxyl pendant groups and to examine the influence of the copolymer chain microstructure and composition on the process of their hydrolytic degradation and cytocompatibility. The work describes copolymerization of cyclic trimethylene carbonate derivative containing benzyl-ester pendant group (benzyl 5-methyl-2-oxo-1,3-dioxane-5-carboxylate) with trimethylene carbonate. The copolymerization was conducted with the use of zinc (II) and lanthanum (III) acetylacetonates as ring-opening polymerization coordination initiators. Detailed NMR analysis allowed to define the microstructure of the obtained copolymers, which depended on the composition and type of used initiator. The final tapered chain microstructure of the obtained copolymers was related to huge differences in comonomers reactivity and evidenced low level of transesterification of the main copolymer backbone. Chosen copolymers, with unprotected carbonyl groups, were subjected to in vitro degradation test and cytocompatibility studies. It was found that high concentration of carboxyl groups resulted in copolymers which formed hydrogels and were very prone to hydrolytic degradation; they were also cytotoxic toward osteoblast-like MG 63 cells. Copolymers with lower content of carboxyl groups were found less susceptible to degradation and cytocompatible with studied cells. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017.

Novel azosystems possessing chemical architecture that allows for noncovalent attachment of the azobenzene or azopyridine chromophores to poly(ester imide) matrix via hydrogen bonding were fabricated. Chosen physicochemical properties including the ability of the chromophores to realign upon linearly polarized light were determined and discussed in relation to details of the materials structure. Calculations based on density functional theory (DFT) were employed to understand and explain a structural reason affecting hydrogen bond formation ability and photoresponsive behavior of the studied azosystems. For the first time, the Fox equation was shown to be applicable for calculating the glass transition temperature of hydrogen-bonded azopolymers. Moreover, it was demonstrated that azopyridine polymers may exhibit a very efficient molecular photo-orientation provided that they possess a proper structural design.

This study describes the preparation, physicochemical characterization and the biological studies of the polymeric delivery systems of proanthocyanidins (PCAN) extracted from Pelargonium sidoides for the potential use as wound dressings. In this study 20 wt% PCAN demonstrated good antimicrobial activity against Staphylococcus aures, a gram-positive wound pathogen. Poly(D,L-lactide) and atactic poly[(R,S)-3-hydroxybutyrate] biopolymers were used to construct biodegradable dressings. A series of polylactide/poly[(R,S)-3-hydroxybutyrate] (P(D,L)LA/a-PHB) blends, containing 10, 20, and 30 wt% of a-PHB were prepared and characterized by means of NMR, GPC, FT-IR, and DSC. Based on the findings, the P(D,L)LA/a-PHB [70/30 wt%] blend with the best thermomechanical properties (Tg value equal 37 °C) was chosen for the preparation of two kinds of electrospun mats, both with and without PCAN. About 50% of PCAN was released from the tested mats during the first 10–12 days of incubation. The electrospun mats with elastic properties, ensuring compatibility with the wound topology, were obtained. The studies of hydrolytic degradation of the constructed mats allowed us to gain complete knowledge of their hydrolysis process, and examine the PCAN release profile as well as identify and characterize the molecular structure of the degradation products of the developed delivery system. Furthermore, preliminary cytotoxicity MTT tests (in vitro) results support the potential application of PCAN-loaded (P(D,L)LA/a-PHB) electrospun mats in wound dressings.

A series of trimethylene carbonate/ l -lactide copolymers with varied comonomers composition were synthesized in bulk, using zinc (II) acetylacetonate and ethyl zinc (II) ethoxide as initiators. The values of the reactivity ratios were determined and they were respectively: r LA = 5.06 and r TMC = 0.89 in case of zinc (II) acetylacetonate and r LA = 13.3 and r TMC = 0.33 in case of ethyl zinc (II) ethoxide. Observed significant differences in reactivity of the comonomers and weak ratio of transesterification processes, resulted in formation of their specific, tapered chains microstructure. This phenomenon caused differences in physico-chemical properties compared to the previously presented TMC/ l -lactide copolymers obtained with other initiators. The presence of long lactidyl blocks caused much higher crystallinity of the copolymers. Investigation indicates on the spherolytic crystal morphology.

Azobenzene-containing poly(amic acid)s and resulting polyimides were synthesized. Polymers differed in the polymer backbone structure and the position at which the azobenzene group was attached to the polymer chain. Polymers were characterized and evaluated using Fourier transform infrared, 1H NMR and UV-visible spectroscopies, X-ray diffraction, differential scanning calorimetry (DSC) and thermogravimetric analysis. Polyimides revealed glass transition temperatures in the range 160–265 °C, and thermal stability with decomposition temperatures in the range 336–444 °C. The thermal imidization kinetics of poly(amic acid)s was investigated by means of DSC. Kinetic parameters, such as the activation energy (E) and the frequency factor, were estimated using the Ozawa and Kissinger models. The values of E, determined using both methods, were in the range 142.52–200.92 kJ mol−1. The photoinduced optical anisotropy (POA) was studied in the obtained azopolymers using a holographic grating recording technique. Surface relief gratings, which appeared after light exposure, were observed using atomic force microscopy. For the first time to the best of our knowledge, photoinduced anisotropy in poly(amic acid)s was studied and compared with POA in their polyimide analogues. © 2014 Society of Chemical Industry

The aliphatic polyurethanes based on atactic poly[(R,S)-3-hydroxybutyrate] (a-PHB) and commercial oligomerols: poly(e-caprolactone)diol and polyoxytetramethylenediol were investigated. a-PHB was obtained by anionic ring-opening polymerization of (R,S)-β-butyrolactone. The 4,4′-methylenedicyclohexyl diisocyanate and 1,4-butanediol were used as contributors of hard segments. The aim of the study was to determine the influence of synthetic, atactic a-PHB in soft segments of polyurethanes on their degradability in simulated body fluids (SBF) and Ringer solution. The incubation of polymer samples in both degradative solutions was carried out for 36 weeks. It was concluded that the presence of a-PHB in polyurethane structure accelerated their degradation in SBF and in Ringer solution and, protected the calcification process.

The degradation process promotes physical and chemical changes in material properties, which can be characterised using thermal analysis techniques. The degree of polylactide film degradation in paraffin, glycerine and propylene glycol (as the thermal properties, crystallinity, thermal stability and decomposition kinetics changes) of the film during degradation at 70 °C, was investigated using dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The changes in the thermal properties, crystallinity and thermal stability of the films during degradation indicate morphological and structural transformations, which result in the deterioration of the material properties for all of the investigated degradation media.

Homo- and copolymers of 4-fluorostyrene (FSt) and styrene (St) were synthesized with different feed ratios using free radical bulk polymerization with azobisisobutyronitrile (AIBN) as initiator. It yielded series of (co)polymers with various amounts of included FSt, P(St-co-FSt) (5–50 mol%) and PFSt. The effect of the initiator concentration on the molecular weights of the homopolymers, that is, PSt and PFSt was investigated. Copolymer compositions were determined by nuclear magnetic resonance spectroscopy. The relative reactivity ratios of both comonomers were determined by applying the conventional linearization methods of Jaacks (J), Finemann–Ross (F–R), inverted Finemann–Ross (IF–R), and Kelen-Tudos (K–T). The reactivity ratios values of St and FSt obtained from J plot are 1.06 and 0.84, F–R plot are 1.18 and 1.06, IF–R 1.01 and 0.86, and K–T plot 1.04 and 0.88, respectively. Thermal properties of prepared (co)polymers, that is, glass transition temperature (Tg) and thermal stability, were determined from differential scanning calorimetry and thermogravimetrical measurements. The lack of significant influence of FSt comonomer content on Tg of (co)polymers was observed. Additionally, the thermal degradation kinetics of obtained PSt and PFSt was studied by thermogravimetric analysis. Kinetic parameters such as the thermal decomposition activation energy (E) and frequency factor (A) were estimated by Ozawa model [E(O) and A(O), respectively] and Kissinger model [E(K) and A(K), respectively]. The activation energy and the frequency factor of PFSt (253 kJ/mol) were higher than PSt (236 kJ/mol). The resulting activation energies estimated using the two methods were quite close. POLYM. ENG. SCI., 54:1170–1181, 2014. © 2013 Society of Plastics Engineers

A new diamine with phthalic diimide moiety, i.e. N,N′-bis(4-amino-2,3,5,6-tetramethylphenyl)phthalene-1,4-dicarboxyimide was synthesized and applied for condensation with 4-(4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoroundecyloxy)benzaldehyde and 4-octadecyloxybenzaldehyde, which resulted in two new azomethine-phthalic diimides (AZ-PDIs). Thermal, optical and electrochemical properties of AZ-PDIs were discussed in relation to their analogous containing instead of five-membered six-membered imide rings (AZ-NDIs) described in our previous work. The phase behavior of AZ-PDIs examined by differential scanning calorimetry (DSC) and polarized optical microscopy (POM) confirms their liquid crystalline properties in wide range of temperatures. AZ-PDIs do not show decomposition below 400 °C as was found based on thermogravimetric analyses (TGA). Optical properties of the prepared compounds were investigated by UV–vis and photoluminescence (PL) measurements. Azomethine-phthalic diimides emitted blue light with emission maximum (λem) at ca. 446–492 nm contrary to azomethine-naphthalene diimides which emitted green light and λem was at 536 and 540 nm. The obtained compounds are electrochemically active and undergo reversible reduction and oxidation as evidenced by differential pulse voltammetry (DPV). The azomethine-phthalic diimides exhibited low electrochemical band gap ca. 1.68 eV being promising for optoelectronic applications.

Poly( l -lactide), PLLA, belongs to the most widely used biodegradable polyesters. These polymers have attracted great attention in recent years due to their excellent material properties, which give a rise to potential applications in various commercial areas. Previously, PLLA reprocessing in a co-rotating twin-screw extruder was used as a model test for material recycling. It may be assumed basing on this study, that PLLA technological wastes may be suitable for reuse, for example, as an additive for neat PLLA. In order to verify such suitability of reprocessed PLLA its degradability under industrial composting conditions was studied at the static composting open-air pile. Incubation of this material in water at 70 °C (abiotic conditions) was also conducted. The progress of the degradation process was monitored by surface changes and measurements of sample weight loss and changes in the PLLA molecular weight. The molecular level structure of the water soluble degradation products of PLLA samples was determined by electrospray ionization multistage mass spectrometry (ESI-MS n ). Lactic acid and its oligomers terminated by hydroxyl and carboxyl end groups were identified as hydrolytic degradation products. The obtained results indicated that in selected environments (industrial composting and incubation under abiotic conditions) hydrolytic degradation via random ester bond scission occurs preferentially. It was demonstrated, that multi-reprocessing of PLLA did not significantly affect the rate of degradation and only slightly affected the disintegration progress of the PLLA samples.

Low molecular weight compounds and polymers consisting of 1 and 2 thiophenes and double azomethine bonds prepared from hydrazine and thiophene aldehydes are presented. The effect of the number of thiophene rings on thermal, optical and electrochemical properties was examined. Polyazine with bithiophene structure exhibited slightly higher both glass transition temperature ( T g = 121 °C) and the decomposition temperature ( T 10 = 345 °C) than polymer with one thiophene ring in repeating unit ( T g = 115 °C, T 10 = 321 °C). A higher degree of conjugation due to presence of bithiophene structure was confirmed by bathochromic shift of the absorbance and photoluminescence. Doping with HCl and FeCl 3 resulted in increase of fluorescence intensity. All the obtained compounds emitted blue light with the highest intensity both in solution and in solid state as a blend with PMMA. The investigated compounds exhibited electrochemical energy gap ( E g ) in the range of 1.94–3.07 eV. Introduction of a second thiophene ring resulted in a decrease of E g by about 0.9 eV in the case of azines and 0.67 eV in polyazines. Additionally, energy band gap ( E g ) was calculated theoretically at B3LYP/6-31G(d,p) level of theory.

The molecules bearing triphenylamine (TPA) structure were widely investigated mainly as active hole-transporting materials for construction of light-emitting diodes. Our previous research was concerned for poly(azomethines) bearing TPA in structure. Now we present research of its model compounds. A series of five conjugated azomethines have been synthesized in reaction of different aromatic diamines and 4-formyltriphenylamine. The structures of given azomethines were characterized by means of FTIR, 1H NMR, and 13C NMR spectroscopy and elemental analysis. Optical, electrochemical and thermal properties of all compounds were investigated by means of differential scanning calorimetry (DSC), UV–vis spectroscopy, photoluminescence spectroscopy and cycling voltammetry. Influence of chemical structure of the compounds on their properties has been analyzed.

New arylene bisimide derivatives, both low molecular compounds and polymers consisting of a naphthalene diimide core and imine linkages were synthesized. The azomethine-diimides were prepared from N,N′-bis(4-amino-2,3,5,6-tetramethylphenyl)naphthalene-1,4,5,8-dicarboximide (DANDI) which was condensed with 4-pyridinecarboxaldehyde or 1,3-benzothiazole-2-carboxaldehyde or 2-thiophenecarboxaldehyde or 2,2′-bithiophene-5-carboxaldehyde. Poly(azomethine-naphthaleneimide)s were obtained by high temperature polycondensation of DANDI with 2,5-thiophenedicarboxaldehyde or 2,2′-bithiophene-5,5′-dicarboxaldehyde. The materials do not show decomposition below 300 °C. The azomethine-diimides exhibited glass-forming properties with glass transition temperatures in the range of 80–195 °C. For the first time, to the best of our knowledge, amorphous molecular naphthalene diimide compounds were obtained. Optical properties of the prepared compounds were investigated by UV–vis and photoluminescence (PL) measurements. Most of the azomethine-diimides emitted green light with the highest intensity with emission maximum ( λ em ) at ca. 519–535 nm contrary to polymers which λ em was at 450 and 485 nm. All the compounds are electrochemically active and azomethine-diimides undergo quasi-reversible reduction and irreversible oxidation as evidenced by cyclic voltammetry (CV). In all studied molecules the electrochemically determined HOMO level is in the range of −5.5 to −5.13 eV whereas the LUMO level is close to −4.0 eV for azomethine-diimides and −3.8 eV for polymers as determined by differential pulse voltammetry (DPV). The investigated compounds exhibited low electrochemical band gap (1.21–1.5 eV) being promising for optoelectronic applications.

A new thermotropic liquid crystals containing azobenzene unit and imine linkages were synthesized via condensation of 4-(4,4,5,5,6,6,7,7,8,8,9,9,10,10,11,11,11-heptadecafluoroundecyloxy)benzaldehyde with 4-aminoazobenzene (AzoAz-1) and 4,4′-diaminoazobenzene (AzoAz-2). The structures of compounds were characterized by means of NMR, FTIR spectroscopy and elemental analysis; the results show an agreement with the proposed structure. The mesomorphic behavior of the unsymmetrical AzoAz-1 and symmetrical AzoAz-2 azobenzeneimines was investigated via differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Based on the POM and DSC measurements AzoAz-1 exhibited smectic phases (SmX, SmA), while AzoAz-2 showed smectic (SmX1, SmX2, SmA) and nematic (N) mesophases. Optical properties of the azobenzeneimines were tested by UV–vis and photoluminescence (PL) spectroscopy in various solvents. Preliminary investigations of electrical properties of the new compounds were carried out by current–voltage (I–V) measurements performed on ITO/compound/Al device.

Low-molecular weight macroinitiators derived from natural poly(3-hydroxyalkanoates) (PHAs), which contain olefinic and activated by 18-crown-6 ether carboxylic end groups, were used in anionic ring opening polymerization (ROP) of racemic β-butyrolactone and new diblock copolymers of selected PHAs (PHB, PHBV, PHO) with atactic poly[(R,S)-3-hydroxybutyrate] (a-PHB) were obtained. These novel copolymers were characterized using 1 H NMR, GPC and DSC. Hydrolytic degradation studies of selected copolymers were also performed. Finally, the suitability of these polymeric materials for cardiovascular engineering and as blend compatibilizers was demonstrated.

Two novel poly(azomethinenaphthaleneimide)s ( poly (AZ-NI)s) and azomethine-naphthalene diimide (AZ-NI) consisting of electron-donating triarylamine with imine linkages and electron-accepting naphthalene diimide moieties were prepared via condensation of N,N′-bis(4-amino-2,3,5,6-tetramethylphenyl)naphthalene-1,4,5,8-dicarboxyimide (DANDI) with 4-formyltriphenylamine, 4,4′-diformyltriphenylamine and 4,4′,4″-triformyltriphenylamine. The thermal degradation kinetics of obtained compounds was studied by TGA. The activation energy ( E a ) of thermal decomposition process was estimated by the first order Coats–Redfern equation and was in the range 115.1–266.7 kJ/mol. Poly (AZ-NI)s and AZ-NI exhibited useful levels of thermal stability, their 5% weight-loss temperatures were above 350 °C. Optical properties of the prepared compounds were investigated by UV–vis and photoluminescence (PL) measurements. The obtained alternating donor–acceptor compounds emitted mainly blue light. The electrochemical behavior of poly (AZ-NI)s, AZ-NI and DANDI was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV). As calculated from CV, the electrochemical energy band gap ( E g ) of the linear polymer was equal to 1.15 eV, but the E g of the branched one was lower: 1.06 eV, whereas the E g of AZ-NI and DANDI was 1.32 and 0.47 eV, respectively. For the first time, to the best of our knowledge, polynaphthaleneimides with triphenylamine units and azomethine linkages have been described in this article.

(Bio)degradable poly(ester-urethane)s containing polylactide (PLA) and poly[(1,4-butylene terephthalate)- co -(1,4-butylene adipate)] (BTA) segments in the main chain were synthesized and their properties were examined. Novel poly(ester-urethane)s were obtained from isophorone diisocyanate (IPDI), synthetic PLA-diol and/or synthetic BTA-diol oligomers in a two-step process. PLA-diol and BTA-diol oligomers were received via glycolysis of their respective polymers: PLA and BTA. Butanediol (BD) was used as a polymer chain extender. The synthesized poly(ester-urethane)s were characterized by DSC, NMR, GPC, FTIR and X-ray methods. The poly(ester-urethane)s that were examined had a single glass transition temperature ( T g ), which pointed to a one-phase system. The biodegradability of the received poly(ester-urethane)s was examined under industrial composting conditions. The results prove the possibility of synthesizing new perspective application materials, surrendering (bio)degradation in the environment.

A new aliphatic–aromatic diamine with naphthalene diimide (DA) moiety and a polyimide with naphthalene and perylene diimide subunits (PI) were synthesized and their thermotropic liquid crystalline behavior was examined by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM). Both compounds exhibited liquid crystalline properties. The temperatures of 5% weight loss ( T 5% ) of the diamine and polyimide range from 350 to 373 °C in nitrogen. The optical properties, that is, UV–vis absorption and photoluminescence (PL) of obtained monomer and polyimide were studied in solution and in solid state as a blend with inert poly(methyl methacrylate) (PMMA). Influence of solvent polarity, excitation wavelength and concentration on DA and PI emission was found. The investigated compounds emitted green light in chloroform solution. Relative PL intensity of the DA and PI was investigated in NMP in relation to rhodamine-B used as a standard. The electrochemical behavior of diamine and polyimide was studied (in solution) by differential pulse voltammetry (DPV). The HOMO and LUMO levels of these compounds were in the range of −5.44 to −6.03 eV and −3.81 eV, respectively. Energy gap ( E g ) values were calculated using cyclic voltammetry (CV) and UV–vis measurements. Introduction of a perylene moiety (PI) resulted in increase of E g (2.22 eV) compared to DA which exhibited a E g value of approximately 1.63 eV. The electrical properties of DA and PI were investigated by current–voltage ( I – V ) measurements on ITO/compound/Al devices.

Methyl methacrylate (MMA) was copolymerized with 9-anthrylmethyl methacrylate (AMA) or 2-(9-carbazolyl)ethyl methacrylate (CMA) under controlled atom transfer radical polymerization (ATRP) conditions. It yielded well-defined luminescent copolymers, which emitted light with various wavelengths and intensities depending on their compositions.

zsyntezowano poliuretany, w ltorych segmenty gietkie SG byly zbudowane z telehelicznego, zakonczonego obustronnie grupami -OH, ataktycznego polihydroksymaślanu (PHB). Wyniki DSC wskazują, ze wprowadzenie PHB zaburza uporządkowanie w obrebie SG i sztywnych, zminejsza sie stopien krystaliczności, zwieksza sie nieco sorpcja wody. Test mikrobiologiczne wytworzonych PUR dowodzą skuteczności sterylizacji plazmą.

In this article, the imidization reaction kinetic of novel poly(ester amic acid)s with azobenzene units as side groups was studied by dynamic experiments by means of differential scanning calorimetry. Polymers differ in the number of chromophore moieties in their repeating unit and position in which azobenzene group is attached to the polymer chain. The kinetic parameters of poly(ester amic acid)s conversion to poly(ester imide)s was compared with data calculated for parent polymer, that is, without azobenzene groups. For the first time to our knowledge, the imidization kinetic of polymers with side azobenzene groups was studied. Kinetic parameters, such as the activation energy and frequency factor were estimated with the by Ozawa model [(E(O) and A(O)), respectively] and Kissinger model [(E(K) and A(K), respectively]. The values of activation energy determined with both models were in the range 167.1–198.3 kJ/mol. The lowest activation energy of imidization reaction exhibited polymer in which azobenzene units were placed between amide linkages. Polymers were characterized by FTIR, 1H-NMR, X-ray, and UV–vis methods. The glass transition temperature of resultant poly(ester imide)s was in the range of 217–237°C. The presence of chromophore units slightly decreased Tg and significantly improved their solubility and optical properties. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

One series of symmetrical azine-type liquid crystals were synthesized and their chemical structure identified by FTIR, NMR, high resolution mass spectrometry-electro spray ionization (MS-ESI) and elemental analysis. The absorption (UV–vis), photoluminescence (PL) and thermoluminescence (TL) features of the compounds are documented. X-ray diffraction was employed to evaluate their phase transitional behaviour. Their mesomorphic properties were investigated by polarizing optical microscopy (POM) and differential scanning calorimetry (DSC). Terminal groups of the liquid crystals had an effect on their mesomorphic properties. Azine with alkoxysemiperfluorinated end-groups ( A1 ) exhibited smectic C (SmC) phase, whereas azine with octadecyloxy end chains ( A3 ) showed SmC and SmA phases. Azine with 5″-octyl-2,2′:5′,2″-terthiophene groups ( A2 ) exhibited only nematic phase. Different types of N and SmC textures were found and investigated by POM technique. Azine with thiophene groups ( A2 ) has an absorption band about 138 nm batochromically shifted compared to the analogous band of other compounds. The lowest optical band gap value (2.34 eV) was detected for A2 . Azines emitted violet or green light. The thermoluminescence emission of azines occurred at about 390–440 nm wavelengths. Current–voltage measurements were performed on ITO/compound/Alq 3 /Al and ITO/TiO 2 /compound/Alq 3 /Al devices before and after light irradiation. To prepare TiO 2 layer, sol–gel technique was applied.

Synthesis, characterization and thermal properties of a series of four azomethines ( 1 )–( 4 ) derived from 4-biphenyl carboxaldehyde were described. The structures of the azomethines were characterized by means FTIR, 1 H, 13 C NMR spectroscopy and elemental analysis; the results show an agreement with the proposed structure. The methods of differential scanning calorimetry (DSC) and polarizing optical microscopy (POM) were used to describe the liquid-crystalline properties of the azomethines. The mesomorphic properties of the compounds depend on the amine used in the synthesis of imines. In particular, three of them prepared from 4-hexadecylaniline, 4-decylaniline or 4-((4-aminophenyl)diazenyl)-N,N-dimethylbenzenamine ( 1 )–( 3 ) showed smectic A and smectic X mesophases, while the last one obtained from 4-(heptadecafluoroctyl)aniline ( 4 ) exhibited SmX2 and nematic mesophases. Current–voltage measurements were performed on ITO/compound/Alq 3 /Al device with two different thicknesses of the film. Additionally, we compared the mesomorphic behavior of the azomethines presented in this work with another azomethines.

N,N-Diglycidylaniline was reacted with aniline (yielding polymer EP-1) and the newly synthesized chromophore 4-(phenylazo)aniline (yielding polymer EP-2). The curing kinetics of these two epoxy resin systems was studied in dynamic experiments by means of differential scanning calorimetry. Kinetic parameters such as the activation energy and frequency factor were estimated with the Ozawa method [E(O) and A(O), respectively], the Kissinger method [E(K) and A(K), respectively], and the modified Avrami method [E(A) and A(A), respectively]. The activation energy and frequency factor of EP-1 were much lower than those of EP-2 estimated with the Ozawa, Kissinger, and Avrami methods. The activation energy and frequency factor for EP-1 determined with the Ozawa method [E(O) = 55.8 kJ/mol, A(O) = 10 × 103 1/s] and the Avrami method [E(A) = 56.4 kJ/mol, A(A) = 9.2 × 103 1/s] were higher than those determined with the Kissinger method [E(K) = 51.0 kJ/mol, A(K) = 2 × 103 1/s]. In the case of EP-2, the kinetic parameters calculated with the Ozawa model [E(O) = 140.4 kJ/mol, A(O) = 12.3 × 1013 1/s] and the Kissinger model [E(K) = 139.9 kJ/mol, A(K) = 10.9 × 1013 1/s] were higher than those calculated with the Avrami model [E(A) = 130.4 kJ/mol, A(A) = 7.9 × 1012 1/s]. The obtained polymers were characterized with Fourier transform infrared, 1H-NMR, differential scanning calorimetry, and ultraviolet–visible spectroscopy. The polymers exhibited low glass-transition temperatures in the range of 57–79°C and good solubility in common organic solvents. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

Three calamitic azomethines were prepared by the condensation of the benzene-1,4-dicarboxaldehyde with the three aliphatic amines (LCOA1–LCOA3). The structures of the azomethines were characterized by means of FTIR, 1H, 13C NMR spectroscopies and elemental analysis; the results showed an agreement with the proposed structure. The azomethines emitted blue or green light. An influence of n-decyl sulfonic acid (DSA) on mesomorphic behaviors, absorption and emission wavelengths was investigated. The liquid crystalline properties of the azomethines were studied by differential scanning calorimetry (DSC), polarizing optical microscopy (POM) and wide and small angle X-ray diffraction (WAXS and SAXS). The mesomorphic properties of the compounds depend on both the length of the outer flexible spacers and the kind of connection between the alkyl groups and the imine group, i.e. directly via aliphatic chain or by phenyl ring. LCOA1–LCOA2 exhibited smectic and nematic phases, whereas the LCOA3 did not exhibit thermotropic liquid crystal properties. Basing on the comparison of thermal behaviors and optoelectronic properties of undoped (LCOAX) and doped (LCOAX/DSA) azomethines it was shown that ionic self-organized processes are powerful and are able to tune: i) the processability, ii) the LC behavior, and iii) the maximum of emission band of the synthesized azomethines.

Supramolecular aggregations have been obtained via ionic self-assembly of conjugated poly(ketanil)s and sulfonic acid derivatives of benzenetricarboxamides. To achieve this goal a new protonating molecule has been synthesized which is a derivative of 1,3,5-benzenetricarboxamide with sulfonic acid group at each of its ends. 1,3,5-benzenetricarboxamides of C3 symmetry tend to form ordered supramolecular aggregations via π-stacking and this property is retained in their sulfonic acid derivative. Because of their Bronsted acid nature the new molecules can additionally associate conjugated polymers with basic centers such as poly(ketanil)s. Depending on the processing solvent used (MC or DMA) 1,3,5- the sulfonic acid derivative of benzenetricarboxamide and its associations with poly(ketanil)s form aggregations of spherullite-like or feather-like morphologies as evidenced by polarized optical microscopy and atomic force microscopy. The similarity of this supramolecular organization is also corroborated by DSC studies which in both cases show endothermic type transitions of the same origin. The supramolecular acid–base associations are semi-crystalline in nature and exhibit good mechanical properties at room temperature because of a rather low Tg, in the vicinity of 300 K. This unusual lowering of Tg by ca. 90 K as compared to the case of poly(ketanil)s in their basic form is caused by the plasticizing effect of the protonating agent. Finally polyketanil–1,3,5-benzenetricarboxamide sulfonic acid derivatives show tunable photoluminescence which depends on the solvent and SO3H/C N molar ratio.

The description of polymer relaxation proprieties is the way to characterize the influence of polymer structure on its useful proprieties of stability and resistance. To perform physicochemical profiles of polymers the synthesis and investigation of model compounds was required. The instrumental methods such as NMR, FTIR, dielectric spectroscopy were used. The results of the experiments allowed us to improve the technology of the synthesis processes and the extension of the range of their usage. Moreover the obtained polymers were more stable and more resistant to degradation. To acquire the profile of the relaxation properties of the linear, hyperbranched and dendrite unsaturated polyester resins, the synthesis of the oligoesters as the model compounds was performed. Pentane-1,5-diol phthalic anhydride was used as substrate of the process. The structures of the obtained model compound were confirmed by elemental analysis and 1H NMR and FTIR spectroscopy. Measurements of the relaxation processes of the model compound were also done. The determination of the α, β and β′ relaxation processes for model oligoesters allow us to describe the practical properties of commercial compounds. The description of model relation of the relaxation process may facilitate the interpretation of the dependence between useful properties of polyesters and their molecular structure.

Shape-memory polymers (SMPs) that combine shape-memory, biodegradability, and controlled drug release properties are very promising for medical and pharmaceutical application. Moreover, incorporation of antirestenotic drug into SMP biodegrad- able stent seems to be an interesting solution because of possibility to combine the mechanical support that provides stent and also drug elution. The aim of our study was to analyze the effect of incorporation of sirolimus into poly(L-lactide-co-glycolide-co-trimethy- lene carbonate) on physicochemical and mechanical properties, degradation, and shape-memory effect of the terpolymer. For this purpose, sirolimus was incorporated into the terpolymer by injection molding method. It has been demonstrated that drug-free ter- polymer after injection molding characterized insignificant changes in terpolymer composition. Degradation of materials during proc- essing was not observed. Incorporation of drug molecules did not change shape-memory properties of terpolymer. 1 H- and 13 C-NMR spectra of poly(lactide-co-glycolide-co-trimethylene carbonate) confirmed that changes during degradation were similar for terpolymer and terpolymer with sirolimus. Sustained and regular release of sirolimus was observed. The developed material presents potential for biomedical and pharmaceutical applications. V C 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41902.

The study of polymer properties requires the synthesis and analysis of simple model compounds. In this work the suitable oligoesters were used for this purpose. The investigation of model oligoesters allows us to describe the physicochemical and utility properties i.e. stability and resistance of linear, branched and dendrite polyesters. To achieve this aim the model oligoesters were synthesized and their physicochemical properties were described. The structure of the oligoesters was confirmed with the use of NMR, FTIR spectroscopy and elemental analysis. A detailed study of the relaxation properties using broadband dielectric spectroscopy and Dynamic Mechanical Thermal Analysis (DMTA) was also performed. A description of the α relaxation process and different dielectric and DMTA β-relaxation processes for the oligoesters are indispensable to determine the relaxation properties of the suitable polyesters.

New luminescent materials - aromatic polyketanils (PKs) containing p-phenylene and biphenylene linkages in the backbone and electron-donating side-group substitutions have been synthesized via melt polycondensation (180°C, 24 h). Their structures were confirmed by elemental and spectral Fourier transform infrared, 13Cand 1H NMR, and ultraviolet-visible (UV-vis) analysis. All the PKs were solution-processable and thermally stable, making them potential candidate materials for applications in microelectronics and aerospace. These ketanil polymers showed high thermal stability and well-defined glass transition temperatures ( Tg). The temperature at which the polymers lose 10% of their weight ( T10) ranged from 420 to 520°C. Depending on the polymer structure, PKs showed Tg values in the range of 133 to 244°C. Moreover, the polymers emit either blue radiation or green radiation depending on the mutual presence of conjugated and saturated chain segments. The HOMO/LUMO energy gap of the polymers was in the range of 2.74-2.19 eV. The photoluminescence properties of the PKs after protonation with DL-camphor-10-sulfonic acid (CSA) were tested. The structure formation of (PKs)1(CSA)2 complexes are discussed on the basis of 1HNMRspectroscopy.

The thermal, mechanical and thermo-mechanical properties of polymer compositions, containing synthetic biodegradable polymers i.e. polylacide (PLA) and aliphatic-aromatic copolyester (BTA), natural biopolyester n-PHB and its synthetic atactic analog (a-PHB) were investigated. Thermal properties of the polymer compositions were studied by means of DSC. The compositions of various polymer weight ratio were tested. Compositions containing BTA and n-PHB create polyphase systems, what was confirmed by DSC. In this case the two Tg and two Tm values were observed. Polymer compositions containing PLA and BTA showed different behaviours. At the BTA content up to 30 weight % only one Td one Tm were indicated. At the increase of the BTA content to 50% weight and above, the two Tg, and two Tm were observed. Mixtures of BTA with n-PHB, PLA and with a-PHB show considerably greater values of the strain (e) in comparison with initial polymers (n-PHB, PLA). It was found that in contrary to mixtures containing PLA, at the BTA content in the mixture with n-PHB above 50% of weights increases not only the strain, but also the stress at break (σ). Strong increase of the e value in PLA/a-PHB mixtures with the content of a-PHB above 30% of weights were observed.

New luminescent materials—aromatic polyketanils (PKs) containing p-phenylene and biphenylene linkages in the backbone and electron-donating, side-group substitutions—were synthesized via melt polycondensation with the goal of studying the interactions between the polymer chains (PKs), primary dopant [1,2-(di-2-ethylhexyl)ester of 4-sulfophthalic acid (PSA)], and secondary dopant [m-cresol (MC)] with 1H NMR, 13C NMR, Fourier transform infrared (FTIR), ultraviolet–visible, and photoluminescence measurements. Spectral changes were observed for the PKs after primary and secondary doping, and they supported ionic- and hydrogen-bond formation between the PKs and the PSA and MC, respectively. This specific interaction of the dopant with the host polymer influenced the PK properties, and the following observations were made: (1) HOMO/LUMO energy gap of the protonated PKs; (2) bathochromic/hypsochromic photoluminescence shifts observed after protonation with PSA; (3) a downfield chemical shift of the labile proton in the protonating agent OH group in the 1H NMR spectra of the protonated polymers; (4) a protonation decrease in the intensity of the CN stretching band in the FTIR spectrum; and (5) a spherulite-like morphology, detected by atomic force microscopy and polarized optical microscopy. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5645–5660, 2006

Supramolecular complexes of alkali metals were used as catalysts in the polymerization of isoprene via a two-electron-transfer mechanism. The obtained polyisoprene, having a living end group, was subsequently used to initiate methyl methacrylate polymerization in tetrahydrofuran. Polyisoprene-poly(methyl methacrylate) block copolymers were obtained, and their structure was established with 1 H NMR, gel permeation chromatography, differential scanning calorimetry, and experiments of selective extraction.

New oligoketanils containing vinylene group in their main chain have been synthesized from diamines and diketones by melt-condensation (180 °C, 24 h). Physical properties of these new polyconjugated systems can be conveniently tuned either by an appropriate design of the repeat sub-unit originating from the diamine or by protonation of imine nitrogens with a protonating agent exhibiting plasticizing properties, for example with 1,2-(di-2-ethylhexyl)ester of 4-sulfophthalic acid (DEHEPSA). In the base (non-protonated) form they emit either blue radiation or green radiation depending on the mutual presence of conjugated and saturated chain segments. Protonation with DEHEPSA transforms blue radiation emitters into the green radiation ones. Simultaneously it results in a large decrease of the glass transition temperatures (Tg), of the systems investigated, from values exceeding 373 K to values close to room temperature, improving by consequence their flexibility.

New conjugated poly(ketanil)s, i.e. polymers containing ketimine groups in their main chain, have been synthesized from 1,4-phenylenediamine (or benzidine) and five different diketones via polycondensation with the goal to obtain new materials of tunable luminescent properties. It is demonstrated that both the absorption and photoluminescence spectra can be modified not only by changing the ratio of conjugated to non-conjugated segment in the polymer main chain but also via acid–base doping involving the protonation of ketimine groups. By combining these two methods, it is possible to precisely tune the emission spectra of poly(ketanil)s in the spectral range of 520–580 nm. The use of bifunctional protonating agents, containing plasticizing groups, for example 1,2-(di-2-ethylhexyl)ester of 4-sulfophthalic acid (DEHEPSA), in addition to the modification of the luminescent spectra, leads to a lowering of the glass transition temperature ( T g ) of the polymers studied by approximately 100–150 K. Thus, the majority of the polymers studied exhibit, in their doped state, the T g below room temperature leading to flexible films of good mechanical properties.

The epoxy resin: N , N -diglycidyl-4-glycidyloxyaniline (DGOA) is cured with the new diamine-chromophore: 2,4-diamino-4′-methylazobenzene (DMAB). The spectral characterization of infrared spectroscopy (FTIR), 1 H NMR spectroscopy and of elemental analysis (EA), confirm the chromophore structure. The curing kinetics of aminophenol epoxy resin/2,4-diamino-4′-methylazobenzene system is studied in isothermal experiments by means of differential scanning calorimetry (DSC). The structural changes occurring during the cure reaction are investigated by Fourier transform infrared spectroscopy (FTIR). Thermal stability characterized by the temperature of 5 and 10% weight loss and residue at 1000 °C of the cured product is studied by thermogravimetric analysis (TGA). Amorphous character of the cured material is determined using X-ray spectroscopy. The preliminary investigations of optical grating recording are carried out.

New conjugated aryl-substituted poly(azomethine)s, termed poly(ketanil)s, have been synthesised from 1,4-phenylenediamine (or 3,3′,5,5′-tetramethylbenzidine) and two different diketones via polycondensation with the goal to obtain new materials with tunable spectroscopic properties. It is demonstrated that both the absorption and photoluminescence spectra of these poly(ketanil)s can be modified not only by changing the chemical constitution of both repeating subunits in the polymer main chain but also via acid-base doping involving the protonation of the ketimine groups. By combining these two methods it is possible to precisely tune the absorption and emission spectra of the poly(ketanil)s. The use of bifunctional protonating agents, containing plasticising groups, for example 1,2-(di-2-ethylhexyl)ester of 4-sulfophthalic acid (DEHEPSA), in addition to modifying the spectroscopic properties of the polymers, leads to a lowering of their glass transition temperature (Tg), improving in such a manner the flexibility of the prepared poly(ketanil)s materials.