13870
2005
2005
eng
article
1
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Comparison of properties of silicon-containing poly(amide-imide)s
New silicon-containing poly(amide-imide)s have been synthesized by direct polycondensation of various aromatic diamines with a dicarboxylic acid containing the dimethylsilylene group and preformed in-tide cycles. These polymers are easily soluble in polar amidic solvents such as N-methylpyrrolidinone (NMP) or dimethylformamide (DMF) and can be cast into thin flexible films or coatings from such solutions. They show high thermal stability, with initial decomposition temperature being above 400 C and glass transition temperature in the range of 220-270 degrees C. Very thin polymer films deposited by spincoating technique onto silicon wafers showed a smooth, pinhole-free surface in atomic force microscopy investigations
0954-0083
allegro:1991-2014
10104305
High Performance Polymers. - ISSN 0954-0083. - 17 (2005), 4, S. 483 - 495
Ion Sava
Maria Bruma
Burkhard Schulz
Thomas Köpnick
Institut für Physik und Astronomie
Referiert
Institut für Physik
26348
1996
1996
eng
article
1
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Heterocyclic polyamides containing hexafluoroisopropylidene groups
allegro:1991-2014
10082173
Internationale Conference on Polycondensation <1996, Paris>: proceedings
Maria Bruma
Corneliu Hamciuc
Elena Hamciuc
Frank W. Mercer
Nataliya Belomoina
Burkhard Schulz
Institut für Physik und Astronomie
Institut für Physik
26351
1996
1996
eng
article
1
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High temperature polyamides containing pendant imide groups
allegro:1991-2014
10082174
International Conference on High Temperaure Polymers <1996, Montpellier>: proceedings
Maria Bruma
Corneliu Hamciuc
Ion Sava
Elena Hamciuc
Frank W. Mercer
P. Fritzsche
Burkhard Schulz
Institut für Physik und Astronomie
Institut für Physik
30958
1996
1996
eng
article
1
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Comparative study of the thermal properties of related aromatic polyhydrazides and poly(1,3,4-oxadiazole)s
http://www3.interscience.wiley.com/journal/5401/home?CRETRY=1&SRETRY=0
10.1002/(SICI)1099-1581(199612)7:12<879::AID-PAT600>3.0.CO;2-X
1042-7147
allegro:1991-2014
10082331
Polymers for advanced technologies. - ISSN 1042-7147. - 7 (1996), 12, S. 879 - 887
Shigen Zhu
Burkhard Schulz
Maria Bruma
Ludwig Brehmer
Institut für Physik und Astronomie
Institut für Physik
24333
1997
1997
eng
article
1
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Poly(hydrazide-ester)s and poly(1,3,4-oxadiazole-ester)s containing pendent phenoxy groups
A series of new arornatic poly(hydrazide-ester)s has been synthesized by solution polycondensation of two diacid dichlorides containing preformed ester groups with phenoxyterephthaloyl dihydrazide or with a mixture of phenoxyterephthaloyl dihydrazide with terephthaloyl- or isophthaloyl dihydrazide in N-methyl-2-pyrrolidinone. The thermal cyclization of the poly(hydrazide-ester)s gave the corresponding poly(1,3,4-oxadiazole-ester)s containing pendent phenoxy groups. The polymers were characterized by viscometry, solubility measurements, IR spectroscopy, differential scanning calorimetry and thermogravimetric analysis.
allegro:1991-2014
10086550
High performance polymers. - 9 (1997), S. 429 - 436
Elena Hamciuc
Corneliu Hamciuc
Maria Bruma
Andre Stoleriu
Burkhard Schulz
Interdisziplinäres Zentrum für Dünne Organische und Biochemische Schichten
24400
1997
1997
eng
article
1
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Aromatic poly(1,3,4-oxadiazole)s as advanced materials
Poly(1,3,4-oxadiazole)s have been the focus of considerable interest with regard to the- production of high- performance materials, particularly owing to their high thermal stability in oxidative atmosphere and specific properties determined by the structure of 1,3,4-oxadiazole ring, which, from the spectral and electronic points of view, is similar to a p-phenylene structure.[1] Besides their excellent resistance to high temperature, polyoxadiazoles have many desirable characteristics, such as good hydrolytic stability, high glass transition temperatures, low dielectric constants, and tough mechanical properties. Some polyoxadiazoles have semiconductive properties, other structures can be electrochemically doped and thus made conductive, and other have liquid-crystalline properties, which make them very attractive for a wide range of high-performance applications. They exhibit excellent fiber- and film-forming capabilities, thus being considered for use as heat-resistant reinforcing fibers for advanced composite materials, highly resistant fabrics for the filtration of hot gases, special membranes for gas separation or reverse osmosis, precursors for highly oriented graphite fibers, films, and blocks to be used in the construction of electronic instruments based on X-rays, neutron beams, or a-particles, or in the construction of nuclear reactor walls. Since they were first reported in 1961,[2] a wide variety of polymers containing 1,3,4-oxadiazole rings have been synthesized, and their preparation, characterization, and physico-mechanical properties have been periodically reviewed .[3-8] This article will present a general overview of this class of polymers and will refer to the work carried out by different researchers in the last ten years with the emphasis on the potential uses of such polymers as advanced materials.
allegro:1991-2014
10086542
Advanced materials. - 9 (1997), 8, S. 601 - 613
Burkhard Schulz
Maria Bruma
Ludwig Brehmer
Interdisziplinäres Zentrum für Dünne Organische und Biochemische Schichten
24401
1997
1997
eng
article
1
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Compared properties of aromatic polyamides containing silicon in the chain
Two series of aromatic polyamides incorporating silicon together with phenylquinoxaline or with hexafluoroisopropylidene groups have been synthesized and their properties have been characterized and compared with those of related polymers. These polymers are easily soluble in polar amidic solvents such as N-rnethyl-2-pyrrolidinone and dimethylformamide, and in tetrahydrofuran, and can be cast into thin, transparent films from solution. The polyamides have weight- and number-average molecular weights in the range of 10000-40000 and 3000-6000, respectively, and polydispersities in the range of 3-10. They show glass transition temperatures in the range of 236 °C-275 °C and decomposition temperatures above 400 °C. The polymer films have low dielectric constants in the range of 3.26-3.68, and good mechanical properties (tensile strength 74-100 MPa, tensile modulus 180-386 MPa), thus being comparable with other high performance dielectrics.
allegro:1991-2014
10086544
Angewandte Makromolekulare Chemie. - 253 (1997), S. 169 - 182
Ion Sava
Marta Szesztay
Maria Bruma
Frank W. Mercer
Burkhard Schulz
Interdisziplinäres Zentrum für Dünne Organische und Biochemische Schichten
24407
1997
1997
eng
article
1
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Heterocyclic polyamides containing hexafluoroisopropylidene groups
New heterocyclic polyamides have been synthesized by solution polycondensation of aromatic diamines containing phenyl- quinoxaline units with diacid chlorides having both imide and hexafluoroisopropylidene (6F) groups. These polymers are soluble in polar aprotic solvents, such as N-methylpyrrolidone (NMP) or N,N-dimethylformamide (DMF), and can be cast into flexible thin films from solutions. They show high thermooxidative stability with decomposition temperatures above 400°C and glass transition temperatures in the range of 225 - 300°C. The polymer films exhibit good chemical resistance towards deluted acids and good electrical insulating properties with dielectric constants in the range of 3.2 - 3.7.
allegro:1991-2014
10086539
Macromolecular symposia. - 122 (1997), S. 303 - 311
Maria Bruma
Corneliu Hamciuc
Elena Hamciuc
Frank W. Mercer
Nataliya Belomoina
Burkhard Schulz
Interdisziplinäres Zentrum für Dünne Organische und Biochemische Schichten
24397
1997
1997
eng
article
1
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Synthesis and Properties of Silicon-containing Polyamides
A series of aromatic polyamides incorporating silicon together with phenylquinoxaline or with hexafluoroisopropylidene groups has been synthesized by solution polycondensation of a silicon-containing diacid chloride with aromatic diamines having phenylquinoxaline rings or hexafluoroisopropylidene groups. These polymers are easily soluble in polar aprotic solvents, such as N-methylpyrrolidinone and dimethylformamide, and in tetrahydrofurane, and can be solution-cast into thin, transparent films having low dielectric constant, in the range of 3.26 to 3.68. These polymers show high thermal stability with decomposition temperature being above 400 °C and glass transition temperature in the range of 236 °C to 275 °C.
allegro:1991-2014
10086543
Journal of applied polymer science. - 65 (1997), S. 1533 - 1538
Ion Sava
Maria Bruma
Burkhard Schulz
Frank W. Mercer
Nataliya Belomoina
Interdisziplinäres Zentrum für Dünne Organische und Biochemische Schichten
25849
1996
1996
eng
article
1
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New polyhydrazides and polyoxadiazoles containing pendent phenoxy groups
allegro:1991-2014
10082202
Angewandte Makromolekulare Chemie. - 235 (1996), S. 111
Corneliu Hamciuc
Burkhard Schulz
Maria Bruma
Institut für Physik und Astronomie
Institut für Physik