High‐temperature elastomers from silarylene‐siloxane‐diacetylene linear polymers

The syntheses and characterization of linear silarylene‐siloxane‐diacetylene polymers 3a–c and their thermal conversion to crosslinked elastomeric materials 4a–c are discussed. Inclusion of the diacetylene unit required synthesis of an appropriate monomeric species. 1,4‐Bis(dimethylaminodimethylsilyl)butadiyne [(CH₃)₂N? Si(CH₃)₂? C?C? C?C? (CH₃)₂Si? N(CH₃)₂] 2 was prepared from 1,4‐dilithio‐1,3‐butadiyne and 2 equiv of dimethylaminodimethylchlorosilane. The linear polymers were prepared via polycondensation of 2 with a series of disilanol prepolymers. The low molecular weight silarylene‐siloxane prepolymers 1a–c (terminated by hydroxyl groups) were synthesized via solution condensation of an excess amount of 1,4‐bis(hydroxydimethylsilyl)benzene with bis(dimethylamino)dimethylsilane. The linear polymers were characterized by ¹H and ¹³C NMR, Fourier transform infrared spectroscopy, gel permeation chromatography, thermogravimetric analysis (TGA), and DSC. The elastomers exhibited long‐term oxidative stability up to 330 °C in air as determined by TGA. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 88–94, 2002     

Synthesis of hydroxy‐terminated,oligomeric poly(silarylene disiloxane)s via rhodium‐catalyzed dehydrogenative coupling and their use in the aminosilane–disilanol polymerization reaction

A series of oligomeric, hydroxy‐terminated silarylene–siloxane prepolymers of various lengths were prepared via dehydrogenative coupling between 1,4‐bis(dimethylsilyl)benzene [H(CH₃)₂SiC₆H₄Si(CH₃)₂H] and excess 1,4‐bis(hydroxydimethylsilyl)benzene [HO(CH₃)₂SiC₆H₄Si(CH₃)₂OH] in the presence of a catalytic amount of Wilkinson's catalyst [(Ph₃P)₃RhCl]. Attempts to incorporate the diacetylene units via dehydrogenative coupling polymerization between 1,4‐bis(dimethylsilyl)butadiyne [H(CH₃)₂Si? C?C? C?C? Si(CH₃)₂H] and the hydroxy‐terminated prepolymers were unsuccessful. The diacetylene units were incorporated into the polymer main chain via aminosilane–disilanol polycondensation between 1,4‐bis(dimethylaminodimethylsilyl)butadiyne [(CH₃)₂N? Si(CH₃)₂? C?C? C?C? (CH₃)₂SiN(CH₃)₂] and the hydroxy‐terminated prepolymers. Linear polymers were characterized by Fourier transform infrared, ¹H and ¹³C NMR, gel permeation chromatography, differential scanning calorimetry, and thermogravimetric analysis, and they were thermally crosslinked through the diacetylene units, producing networked polymeric systems. The thermooxidative stability of the networked polymers is discussed. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1334–1341, 2002     

Synthesis and Characterization of Silazane-Based Polymers as Precursors for Ceramic Matrix Composites

The goal of this investigation was to optimize the synthesis of silazane-based polymers for processing fibre-reinforced ceramic matrix composites (CMCs). Liquid oligomeric silazanes were synthesized by ammonolysis of chlorosilanes and characterized spectroscopi- cally (FTIR, NMR) as well as by elemental analysis. The silazanes were obtained in high yield and purity. Different functional groups (system S1: Si—H, Si—CH₃, Si—CH=CH₂) and different degrees of branching in the Si—N backbone [system S2; Si(NH)₃, Si(NH)₂] were realized in order to study the properties of the silazanes that are dependent on the molecular structure. For processing ceramics via pyrolysis of pre-ceramic oligomers, molecular weight, rheological behaviour, thermosetting and ceramic yield were investigated systematically and correlated with the molecular structure of the silazanes. Low molecular weights (500–1000 g mol⁻¹) as well as low viscosity values (0.1–20 Pa s) enable processing of the silazanes in the liquid phase without any solvent. Due to the latent reactivity of the functional groups, curing of the polymers via hydrosilylation is achieved. Structural changes and weight loss during polymer curing as well as the organic/inorganic transition were monitored by FTIR spectroscopy and differential thermogravimetric analysis. With increasing temperature (room temperature to 800 °C) the hydrogen content decreases from 7 to < 0.5 wt% due to the formation of gaseous molecules (NH₃, CH₄, H₂). High ceramic yields up to 80% were reached by branching the oligomers, thus reducing the amount of volatile precursor fragments. Up to 1300 °C, ceramic materials remained amorphous to X-rays. At higher temperatures (1400–1800 °C) either SiC or SiC/Si₃N₄ composites were selectively crystallized, depending on the pyrolysis conditions. The utility of the optimized precursors for CMCs has been demonstrated by infiltration of fibre preforms and subsequent pyrolysis. © 1997 by John Wiley & Sons, Ltd.     

Synthesis and functionalization of Poly[5,5′‐(silylene)‐2,2′‐dithienylene]s using silyl triflate intermediates†

Treatment of 5,5′‐dilithio‐2,2′‐dithiophene with (dimethylamino)methylsily bis(triflate)‐ or α, ω‐bis(triflate)‐substituted trisilanes gave poly[5,5′‐(silylene)‐2,2′‐dithienylene]s in high yields. The amino–silyl bond was cleaved selectively by triflic acid, leading to triflate‐substituted derivatives. Conversion of these compounds with nucleophiles gave other functionalized polymers. Platinum‐catalyzed hydrosilylation reactions between silicon–vinyl and silicon–hydrogen derivatives result in polymer networks which may serve as interesting preceramic materials. The structures of the polymers were proven by NMR spectroscopy (²⁹Si, ¹³C, ¹H). Results of thermal gravimetric analysis (TGA), UV spectrometry and conductivity measurements are given. Copyright © 1999 John Wiley & Sons, Ltd.     

Hydrido(hydrosilylene)tungsten Complexes: Dynamic Behavior and Reactivity Toward Acetone

Reaction of a labile tungsten nitrile complex, [(Cp*)W(CO)₂(NCMe)Me] (Cp*=η⁵‐C₅Me₅), with H₃SiC(SiMe₃)₃ gave the hydrido(hydrosilylene) complex [(Cp*)(CO)₂(H)W?Si(H){C(SiMe₃)₃}] ( 1a ). The hydrido(silylene) complex [(η⁵‐C₅Me₄Et)(CO)₂(H)W?SiMes₂] ( 2 ) (Mes=2,4,6‐Me‐C₆H₂) was synthesized by a similar reaction with H₂SiMes₂. There is a strong interligand interaction between the hydrido and silylene ligands of these complexes; this was confirmed by a neutron diffraction study of [D₂] 1b , that is, the deuterido and η⁵‐C₅Me₄Et derivative of 1a . The exchange between the W? H and the Si? D groups was observed in the deuterido complex [D] 1a . This H/D exchange proceeded slowly at room temperature, but very rapidly under UV irradiation. Variable‐temperature NMR spectroscopy measurements show the dynamic behavior of carbonyl ligands in 1a . Complex 1a reacted with acetone at room temperature to give mainly a hydrosilylation product, [(Cp*)(CO)₂(H)W?Si(OiPr){C(SiMe₃)₃}] ( 3a ), along with a siloxy complex, [(Cp*)(CO)₂WO(Si(H)iPr{C(SiMe₃)₃})] ( 4a ). At low temperature, a different reaction, namely, α‐H abstraction, proceeded to give an equilibrium mixture of 1a and a dihydrido(silyl) complex, [(Cp*)(CO)₂(H)₂W(Si(H){OC(?CH₂)Me}{C(SiMe₃)₃})] ( 5 ).     

Homologous series of alkylsilylphenyl‐substituted poly (p‐phenylenevinylene)s for light‐emitting diodes

Substituent‐induced electroluminescence polymers—poly[2‐(2‐dimethyldodecylsilylphenyl)‐1,4‐phenylenevinylene] [(o‐R₃Si)PhPPV], poly[2‐(3‐dimethyldodecylsilylphenyl)‐1,4‐phenylenevinylene] [(m‐R₃Si)PhPPV], and poly[2‐(4‐dimethyldodecylsilylphenyl)‐1,4‐phenylenevinylene] [(p‐R₃Si)PhPPV]—were synthesized according to the Gilch polymerization method. The band gap and spectroscopic data were tuned by the dimethyldodecylsilyl substituent being changed from the ortho position to the para position in the phenyl side group along the polymer backbone. The weight‐average molecular weights and polydispersities were 8.0–96 × 10⁴ and 3.0–3.4, respectively. The maximum photoluminescence wavelengths for (o‐R₃Si)PhPPV, (m‐R₃Si)PhPPV, and (p‐R₃Si)PhPPV appeared around 500–530 nm in the green emission region. Double‐layer light‐emitting diodes with an indium tin oxide/poly(3,4‐ethylenedioxythiophene)/polymer/Al configuration were fabricated with these polymers. The turn‐on voltages and the maximum brightness of (o‐R₃Si)PhPPV, (m‐R₃Si)PhPPV, and (p‐R₃Si)PhPPV were 6.5–8.7 V and 1986–5895 cd/m², respectively. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2347–2355, 2004     

Ab initio study of mechanism of forming a spiro-heterocyclic ring compound involving Si from dichlorosilylenesilylene (Cl2Si=Si:)→Cl2Si=Si: and aldehyde

The mechanism of the cycloaddition reaction between singlet dichlorosilylenesilylene (Cl₂Si=Si:)→Cl₂Si=Si: and aldehyde has been investigated with the CCSD(T)//MP2/6-31G* method. From the potential energy profile, it could be predicted that the reaction has one dominant reaction pathway. The reaction rules presented is that the two reactants firstly form a four-membered ring silylene through the [2+2] cycloaddition reaction. Because of the 3p unoccupied orbital of Si: atom in the four-membered ring silylene and the π orbital of aldehyde forming a π → p donor–acceptor bond, the four-membered ring silylene further combines with aldehyde to form an intermediate. Because the Si: atom in the intermediate happens sp ³ hybridization after transition state, then the intermediate isomerizes to a spiro-heterocyclic ring compound involving Si via a transition state.     

Synthesis of poly{[bis(diethynylphenyl)silylene]phenylene}s with highly heat-resistant properties and an application to conducting materials

Poly{[bis(3,5-diethynylphenyl)silylene]-p-phenylene} was prepared by the reaction of poly[(diethoxysilylene)-p-phenylene] with 3,5-bis(trimethylsilylethynyl)phenyllithium, followed by desilylation of the resulting substitution product. The present polymer exhibited extremely high heat-resistance and their thermogravimetric analysis (TGA) in a nitrogen atmosphere showed the temperature of 5% weight loss (Td₅) of 791 °C. Total weight loss at 1000 °C in TGA was determined to be 6% based on the initial weight. Treatment of a polymer film on a quartz plate at 1200 °C in vacuo led to the formation of a conducting thin film with a thickness of 74 nm and a conductivity of 9 S/cm.     

An Electrophilic Carbene‐Anchored Silylene–Phosphinidene

The cyclic alkyl(amino) carbene‐anchored silylene–phosphinidene was isolated as L−Si−P(:cAAC−Me) (L=benzamidinate) at room temperature, synthesized from the reduction of L−Si(Cl₂)−P(:cAAC−Me) ( 1 ) using two equivalents of KC₈. Compound 1 was prepared by the oxidative addition of a chlorophosphinidene to the benzamidinate substituted silylene center. This is the first molecular example of a silylene–phosphinidene characterized by single‐crystal X‐ray structural analysis. Moreover, ¹H, ³¹P, and also ²⁹Si NMR spectroscopic data supported the formulation of the products. The theoretical calculations of compound 2 are in good agreement with the experimental results.     

Solubility of carbon dioxide,methane, and propane in silicone polymers. Effect of polymer backbone chains

The solubility of carbon dioxide, methane, and propane in poly(dimethyl silmethylene) [(CH₃)₂SiCH₂]_x and poly(tetramethyl silhexylene siloxane) [(CH₃)₂Si (CH₂)₆Si (CH₃)₂O]_x was measured in the temperature range from 10.0 to 55.0°C and at elevated pressures. The present results are compared with similar measurements made with other silicone polymers. At a given temperature and pressure, the solubility of the above three gases is highest in poly(dimethyl siloxane) (Me₂SiO)_x. The gas solubility is decreased by either backbone-chain or side-chain substitutions of functional groups in (Me₂SiO)_x which increase the stiffness of the polymer chains and decrease the specific or fractional free volume of the polymers. It is conjectured that a decrease in the free volume of silicone polymers has a greater effect in decreasing the gas solubility than differences in gas/polymer interactions [with the exception of specific interactions (e.g., between CO₂ and polar groups in the polymer)]. © 1993 John Wiley & Sons, Inc.     

Synthesis and characterization of novel ferrocenyl glycidyl ether polymer,ferrocenyl poly (epichlorohydrin) and ferrocenyl poly (glycidyl azide)

Poly (ferrocenyl glycidyl ether) was synthesized by polymerization of 2-[(4-ferrocenylbutoxy)methyl]oxirane (FcEpo) using toluene solution of methylaluminoxane as the catalyst. Copolymerization of 2-[(4-ferrocenylbutoxy)methyl]oxirane with epichlorohydrin was used for the synthesis of another ferrocenyl based poly (epichlorohydrin). Ferrocenyl based poly (glycidyl azide), GAP, was synthesized by treatment of sodium azide with this copolymer in DMF as solvent at room temperature. The synthesized ferrocenyl based polymers were characterized by FT-IR, ¹HNMR, UV–Vis, TGA, DSC and GPC analysis. The UV–Vis spectra of synthesized polymers show the absorption band of ferrocene moiety at about 450 nm. The TGA and DSC analysis show that poly (ferrocenyl glycidyl ether) has good thermal stability. The TGA analysis shows that the copolymerization of 2-[(4-ferrocenylbutoxy)methyl]oxirane with epichlorohydrin improved the thermal stability of the copolymer. The GPC analysis of poly (ferrocenyl glycidyl ether), ferrocenyl based poly (epichlorohydrin) and Ferrocenyl based poly (glycidyl azide) show the PDI between 1.14–1.17. The electrochemical behavior of synthesized polymers was investigated by cyclic voltammetry (CV) measurements. The CV curves of synthesized polymers show good electrochemical performance and there is one redox system with the single-electron reversible reaction that associated with ferrocene moiety in polymers structure. The anodic and cathodic peak currents increased with scan rate confirmed redox reactions in the system are kinetically fast diffusion-controlled reactions.     

A Zwitterionic Silylene as Reactive Intermediate and Its Unusual Dimerization to an N‐Heterobicyclic Disilane

A way to synthesize the transient zwitterionic silylene L′Si : 8 {L’=CH[(C=CH₂)CMe(N(tBu))₂]} and achieve its facile dimerization to the remarkable N‐heterobicyclic disilane 8 ₂ is described. At first, employing the β‐diketiminate ligand L [L=CH(CMeN(tBu))₂], both starting materials LH ( 2 ) and its N‐lithium salt LLi ( 3 ) can react with SiBr₄ to yield the silylene precursor L′SiBr₂ ( 4 ) by silicon‐induced C? H activation at an exocyclic methyl group on the backbone of the ligand. Compound 4 reacts with SiBr₄ above room temperature to afford the unexpected terminal CH(SiBr₃)‐substituted dibromosilane 6 along with the unique tricyclic trisilane 7 . Reduction of 4 with KC₈ at 0 °C furnishes the novel N‐heterobicyclic disilane 8 ₂, which is a formal dimer of the desired zwitterionic silylene L′Si : ( 8 ). It has been reasoned that compound 8 ₂ may results from [4+1] cycloaddition of two molecules of 8 to give the transient dimer 8 ₂ ′ , which subsequently undergoes hydrogen transfer from a terminal methyl group on the backbone of the C₃N₂Si ligand to the low‐coordinate Si atom. The latter dimerization can be rationalized by the intrinsic zwitterionic character of 8 and insufficient steric protection through the tBu groups at the nitrogen atoms. The novel compounds 3 , 4 , 6 , 7 , and 8 ₂ have been characterized by ¹H, ¹³C, and ²⁹Si NMR spectroscopy, mass spectrometry, and elemental analysis. Additionally, the structures of 3 , 6 , 7 , and 8 ₂ were also established by single‐crystal X‐ray diffraction analyses.     

Synthesis and properties of novel conjugated poly(silylacetylene silazane)s

A series of novel conjugated polymers, poly(silylacetylene silazane)s having different substituents, were prepared by ammonolysis of the corresponding α,ω‐dichlorosilyleneacetylene oligomers. The structures and properties of the poly(silylacetylene silazane)s were characterized by Fourier transform infrared, ¹H, ¹³C, ²⁹Si NMR, and elemental analyses, gel permeation chromatography, thermogravimetric analysis, differential scanning calorimetry, and spectrofluorophotometry. The resulting polymers had good thermal properties and were moderately fluorescent. Their thermal stability was improved, and obvious red shift was observed when a phenyl substituent was attached on a silicon atom of polymers in the emission spectra. These polymers have the potential to be used as light‐emitting materials with good thermal stability. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2897–2903, 2004     

Exhaustive and partial alkoxylation of polymethylhydrosiloxane by copper‐catalyzed dehydrocoupling with alcohols: Synthesis,crosslinking behavior,and thermal properties of the products

Polymethylhydrosiloxane (PMHS) reacts with aliphatic and aromatic alcohols at room temperature in the presence of [CuH(PPh₃)]₆ complex catalyst to give poly[(methyl) (alkoxy)siloxane]s in high yields. Reactivity of alcohols decreases in the order of p‐methoxyphenol > p‐cresol > phenol > benzyl alcohol > allyl alcohol > ethanol > isopropanol > tert‐butyl alcohol. Partially p‐cresylated polymers, which still retain unreacted Si? H bonds, react further with ethylene glycol or water to form cross‐linked polymers, which, depending on the extent of cross linking, gelate during the cross‐linking process. Propargyl alcohol reacts with PMHS very rapidly to give exhaustively and partially propargyloxylated PMHS. Resulting polymers, upon heating, undergo crosslinking. Partially propargyloxylated polymers display high thermal stability [T_d5 (temperature of 5% weight loss) > 500 °C] as compared with starting PMHS (243 °C) and exhaustively propargyloxylated one (414 °C). © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011     

Heat stable and organosoluble benzoxazole or benzothiazole-containing poly(imide-ester)s and poly(etherimide-ester)s: synthesis and characterization

Two series of poly(imide-ester)s (PIEs) and poly(ether-imide-ester)s (PEIEs), having benzoxazole or benzothiazole pendent groups, were conveniently prepared by the diphenylchlorophosphate-activated direct polyesterification of two bis(imide-carboxylic acid)s (1), such as 2-[3,5-bis(N-trimellitimidoyl)phenyl]benzoxazole (1 _O ) and 2-[3,5-bis(Ntrimellitimidoyl) phenyl]benzothiazole (1 _S ) and two bis(imide-ether-carboxylic acid)s (2), such as 2-[3,5-bis(4-trimellitimidophenoxy)-phenyl]benzoxazole (2 _O ), and 2-[3,5-bis(4-trimellitimidophenoxy)-phenyl]benzothiazole (2 _S ) with various aromatic dihydroxy compounds in the presence of pyridine and lithium chloride. The structures, solubilities and thermal properties of obtained polymers were investigated in detail. All of the resulting polymers were characterized by FTIR and ¹H-NMR spectroscopy and elemental analysis. All of the resulting polymers exhibited excellent solubility in common organic solvents, such as pyridine, tetrahydrofuran and m-cresol, as well as in polar organic solvents, such as N-methyl-2-pyrrolidone, N,N-dimethylacetamide, N,N-dimethylformamide and dimethyl sulfoxide. The modified polymers were obtained in quantitative yields with inherent viscosities between 0.47 and 0.67 dl·g^?1. Experimental results indicated that all the polymers had glass transition temperature between 198 °C and 262 °C, the decomposition temperature at 10% weight loss between 398 °C and 531 °C under nitrogen.     

The Synthesis of (η3‐C3H5)Pd{Si[N(tBu)CH]2}Cl and the Catalytic Property for Heck Reaction

Treatment of N‐heterocyclic silylene Si[N(^tBu)CH]₂ ( 1 ) and [(η³‐C₃H₅)PdCl]₂ in toluene led to the formation of the mononuclear complex (η³‐C₃H₅)Pd{Si[N(^tBu)CH]₂}Cl ( 3 ), the silicon analogue to N‐heterocyclic carbene complex (η³‐C₃H₅)Pd{C[N(^tBu)CH]₂}Cl ( 2 ). Complex 3 was characterized with ¹H NMR and ¹³C NMR. Investigation shows that (η³‐C₃H₅)Pd{Si[N(^tBu)CH]₂}Cl is an active catalyst for Heck coupling reaction of styrene with aryl bromides.     

Synthesis and electro-optical features of a high T g polymer system with excellent electro-optic activity and thermal stability

Three chromophores with tricyanofuran and tricyanopyrroline electron acceptors were synthesized and doped in high glass transition temperature (T _g) polymer poly(N-(4-acetoxylphenyl)maleimide-co-styrene, NAPMI-co-ST). The electro-optic (EO), optical, and thermal properties of the doped poly(NAPMI-co-ST) were characterized and discussed. After being corona poled under 12?kV, this high T _g polymer material showed excellent EO activity and thermal stability. The highest EO coefficient (r ₃₃) reached 48.2?pm?V^?1 (1,310?nm) and could remain 90?% of the original value for 100?h at 85?°C. The EO coefficient was relatively higher compared with other high T _g EO polymers. The thermal stability was also very good and the manufacture process was convenient and applicable for device fabrication.     

Organosilicon polymers with bis-acetylenic units: Conductivity and ceramisation studies

The transformation poly[(silylene)diacetylene] into ceramic have been studied and SiC obtained with a quantitative yield: all the silicon atoms present in the starting material are converted into SiC. The key step is the crosslinkage of C₄ units into a carbon matrix in which the R₁SiR₂ moieties are in the vicinity one to each other allowing the quantitative transformation into SiC. The carbon content of the resulting ceramic depends on the nature of R₁ and R₂ groups. The excess of carbon has been used for the carboreduction of oxides (TiO₂, ZrO₂, HfO₂, etc…) and mixed ceramics with interpenetrating network have been obtained: SiC / TiC, SiC / ZrC, etc… Under nitrogen atmosphere, the ceramisation leads to different systems such as SiC / TiN, SiC / AlN, etc…     

The synthesis of poly(phenylacetylene)s with bulky chiral silyl groups and the thermal stability of their helical conformation

The polymerization of (−)‐p‐[(tert‐butylmethylphenyl)silyl]phenylacetylene (t‐BuMePhSi*PA) and (+)‐p‐[{methyl(α‐naphthyl)phenyl}silyl]phenylacetylene (MeNpPhSi*PA) with the [(nbd)RhCl]₂ Et₃N catalyst yielded polymers with very high molecular weights over 2 × 10⁶ in high yields. The optical rotations of the formed poly(t‐BuMePhSi*PA) and poly(MeNpPhSi*PA) were as high as −356 and −150° (c = 0.11 g/dL in CHCl₃), respectively. The circular dichroism (CD) spectrum of poly(t‐BuMePhSi*PA) in CHCl₃ exhibited very large molar ellipticities ([θ]) in the UV region: [θ]_max = 9.2 × 10⁴ ° · cm² · dmol⁻¹ at 330 nm and −8.0 × 10⁴ ° · cm² · dmol⁻¹ at 370 nm. The [θ]_max values of poly(MeNpPhSi*PA) were also fairly large: [θ]_max = 7.1 × 10⁴ ° · cm² · dmol⁻¹ at 330 nm and −5.3 × 10⁴ ° · cm² · dmol⁻¹ at 370 nm. The optical rotations of poly(t‐BuMePhSi*PA) and poly(MeNpPhSi*PA), measured in tetrahydrofuran, chloroform, and toluene solutions, were hardly dependent on temperature in the range 22–65 °C. The CD effects of these polymers hardly changed in the temperature range 28–80 °C, either. These results indicate that the helical structures of these polymers are thermally appreciably stable. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 71–77, 2001     

Poly(1,3,4-oxadiazole-ether-imide)s and their polydimethylsiloxane-containing copolymers

Poly(1,3,4-oxadiazole-ether-imide)s were prepared by thermal imidization of poly(amic-acid) intermediates resulting from the solution polycondensation reaction of a bis(ether-anhydride), namely 2,2′-bis-[(3,4-dicarboxyphenoxy)phenyl]-1,4-phenylenediisopropylidene dianhydride, with different aromatic diamines containing 1,3,4-oxadiazole ring, such as 2,5-bis(p-aminophenyl)-1,3,4-oxadiazole, 2,5-bis[p-(4-aminophenoxy)phenyl]-1,3,4-oxadiazole, 2-(4-dimethylaminophenyl)-5-(3,5-diaminophenyl)-1,3,4-oxadiazole. Poly(1,3,4-oxadiazole-ether-imide)-polydimethylsiloxane copolymers were prepared by polycondensation reaction of the same bis(ether-anhydride) with equimolar quantities of an aromatic diamine having 1,3,4-oxadiazole ring and a bis(aminopropyl)polydimethylsiloxane oligomer of controlled molecular weight. A solution imidization procedure was used to convert quantitatively the poly(amic-acid) intermediates to the corresponding polyimides. All the polymers were easily soluble in polar organic solvents such as N-methylpyrrolidone and N,N-dimethylacetamide. The polymers showed good thermal stability with decomposition temperature being above 400 °C. Solutions of some polymers in N-methylpyrrolidone exhibited blue fluorescence, having maximum emission wavelength in the range of 370-412 nm.