Eugenia Grabiec

Poly(amide imides) and poly(ether imides) containing 1,3,4-oxadiazole or pyridine rings: characterizations and optical properties.

Two series of new aromatic polyimides were synthesized from 2,5-bis(4-aminophenyl)-1,3,4-oxadiazole and 2,5-diamino-pyridine and various diamidedianhydrides and dietherdianhydride via high-temperature polycondensation in N-methyl-2-pyrrolidinone. The structures of polymers were characterized by means of FTIR, (1)H NMR spectroscopy, and elemental analysis; the results showed an agreement with the proposed structure. The polymers exhibited high glass-transition temperatures (T(g) = 199-290 degrees C) and high thermal stability with decomposition temperatures (T(d)) in the range of 437-510 degrees C. The optical properties, that is, absorption and photoluminescence (PL) of synthesized polymers, were investigated in solution and in solid state as a blend with inert poly(methyl methacrylate) (PMMA). The polymers in solution emitted violet-blue light in the range of 417-453 nm depending on the polymer structure. The polymers containing pyridine rings in the backbone emitted light at a longer wavelength than polymers with oxadiazole units. The effect of solvent polarity on polymer emission was found. Additionally, the photoluminescence properties of the polymers before and after protonation with HCl were tested.

New semiladder polymers. Part II: Synthesis and properties of new poly(amideimidazopyrrolones)

Abstract A series of polymers from new diamidedianhydrides of arylene-di(benzene-5-amido-1,2-dicarboxylic) anhydride type and aromatic tetraamines (3,3′-diaminobenzidine and 3,3′,4,4′-tetraaminodiphenylether) were synthesized using one step high temperature polycondensation in m -cresol and p -chlorophenol at 180°C and low temperature polycondensation. The polymers had a semiladder structure. The influence of the monomer structure and polycondensation method on the polymer properties has been investigated.

New semiladder polymers: III. Synthesis and properties of new poly(etherimidazopyrrolone)s

Abstract A series of polymers from dietherdianhydrides of arylene-di(benzene-5-ether-1,2-dicarboxylic) anhydride type and tetraamines: 3,3′-diaminobenzidine and 3,3′,4,4′-tetraaminodiphenyl ether were synthesized using high and low temperature polycondensation. The polymers had a semiladder structure. The influence of the monomer structure on the polymer properties has been investigated.

New semiladder polymers: 1. Synthesis and properties of new poly(esterimidazopyrrolone)s

Abstract A series of polymers formed from diesterdianhydrides of arylene-di(benzene-5-estro-1,2-dicarboxylic) anhydride type and tetraamines, 3,3′diaminobenzidine and 3,3′,4,4′tetraaminodiphenyl ether, has been synthesized using one-step high temperature polycondensation in m-cresol at 180°C. The relation between polymer reduced viscosity and reaction time was studied and structures of the polymers were detected by FTi.r. spectroscopy.

Novel soluble aromatic poly(amideimide)s containing 9,9-diphenylfluorene moieties: characterization and optical properties

A series of aromatic poly(amideimide)s containing 9,9-diphenylfluorene moieties and the amide units in the main chain have been synthesized by solution polycondensation reaction of newly prepared diamidedianhydride with several aromatic diamines: 1,3-phenylenediamine, 3,3′-dimethoxy-biphenyl-4,4′-diamine, 4,4′-oxydianiline, 4,4′-(1,3-phenylenedioxy)dianiline, 4,4′-(9-fluorenylidene)dianiline and 1,5-diaminonaphthalene. Molecular structures of the polymers obtained have been characterized using 13C NMR, 1H NMR and FTIR spectroscopies. The polymers prepared are readily soluble in aprotic polar solvents, and form optically transparent films by solution casting. The resultant poly(amideimide)s have been analyzed by differential scanning calorimetry (DSC), thermogravimetry (TG) and wide-angle X-ray diffraction measurements. They exhibited high levels of thermal stability, with decomposition temperatures in the range 452–494 °C, and high glass transition temperatures (181–278 °C). The optical behavior of these polymers has been investigated in NMP solution as well as in the films. The photoluminescence (PL) spectra of the free-standing films prepared from the poly(amideimide)s exhibited maximum emission bands around 506–525 nm in the green region.

Holographic grating recording in azobenzene functionalized polymers

A group of 22 polymers have been synthesized to test their suitability for recording holographic gratings. Polyamides, polyimides, polyesters and their combinations were functionalized with pendant azobenzene groups containing single or double N=N. The polymers were studied using a standard degenerate two-wave mixing technique, which enables measurement of light-induced periodic modification of polymer refractive index and absorption coefficient by analysis of the diffracted light. Two qualitatively different configurations of the holographic polarization recording were used, s-s and s-p. The relationship between structural properties of polymer matrix and azobenzene groups and the holographic grating recording kinetics and light diffraction efficiency was investigated.

Influence of poly(amide-imide)s structures on holographic grating recording

Novel azobenzene functionalized poly(amide-imide)s (PAIs) having azo-benzene group in side chain of polymers were prepared. FTIR spectroscopy and elemental analyses confirm structure and the existence of azo-benzene chromophores in obtained polymers. The relationship between structure of polymers and their physical and optical properties was studied. Thermal behaviour such as glass transition temperature and thermal stability were measured. The influence of the main chain structure of poly(amide-imide)s on polarization gratings recording using standard degenerate two-wave mixing technique with 514.5 nm Ar+ laser line has been investigated.

Optically induced gratings in azo-functionalized polymers studied by a moving grating technique

Light-induced optical anisotropy have been studied by laser grating inscription method within the group of novel azobenzene functionalized polymers. Undergoing light-induced trans-cis-trans photoisomerisations azo-benzene groups were covalently bonded to the main chains of polymers. Two-wave mixing technique was employed to inscribe the amplitude and phase gratings in these polymers. Using two light polarization geometries s-s an s-p we were able to study differences in grating properties as well as ability of surface relief grating formation in studied class of polymers. The supplementary technique of moving grating was used as a tool for obtaining information on contribution of various reorientations of chromophores and main chains to light diffraction on the obtained periodic structures.

New Polyimides as Precursors for Functionalized Polymers

A series of copolymers from 3,3′,4,4′-benzophenonetetracarboxylic di-anhydride and 3,3′,4,4′-biphenyltetracarboxylic dianhydride and two diamines, 4,4′-diaminodiphenylether and 3,5-diaminobenzoic acid, were synthesized. The influence of various ratios of diamines on the properties of polymers were investigated. A preliminary study on the potential of using the carboxylic acid group for substitution was carried out.

Influence of the structure of new poly(amide-imide)s on their optical properties

Abstract Two classes of poly(amide-imide)s with mono- and bisazoaromatic chromophores in the side chain have been synthesized using one-step hightemperature polycondensation. The influence of the structures of the macromolecules on their properties was investigated. Preliminary results of the kinetics of holographic grating recording using 514.5 nm Ar+ laser light for chosen poly(amideimide) films are presented. The gratings were recorded using two linearly polarized beams with s-s or s-p configurations. For comparative purposes all experimental conditions (light intensity, two-beams intersection angle) were kept unchanged. It was found that time constants of grating build-up were significantly larger for polymers containing a chromophore with two azo groups when compared with the same polymers having a single azo group. On the other hand diffraction efficiencies were lower for polymers containing a chromophore with two azo groups than with a single azo group.