Convenient approach to novel functional substituted and branched poly(silylenemethylenes)

Novel poly(silylenemethylenes) have been prepared by the ring-opening polymerization of 1,3-disilacyclobutanes followed by a protodesilylation reaction with triflic acid. The silicon–aryl bond cleavage could be controlled by using different leaving groups, for instance phenyl- and para-anisyl substituents. The reactions of the triflate derivatives with organomagnesium compounds, LiAlH₄, amines, or alcohols gave functional substituted poly(silylenemethylenes). Hydrosilylation reactions or reductive coupling with potassium–graphite led to organosilicon network–polymers, which may serve as suitable precursors for silicon carbide and Si/C/N-based materials. The structures of the polymers were identified by NMR spectroscopy (²⁹Si, ¹³C, ¹H). © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 725–735, 1998     

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.     

Preparation and thermal properties of asymmetrically substituted poly(silylenemethylene)s

Poly(silylenemethylene)s of the types [SiMeRCH₂]_n and [SiHRCH₂]_n were prepared by the ring-opening polymerization (ROP) of 1,3-disilacyclobutanes (DSCBs) containing n-alkyl substituents, such as C₂H₅, n-C₃H₇, n-C₄H₉, n-C₅H₁₁, and n-C₆H₁₃, or a phenyl group on the Si. These new polymers include a monosilicon analog of poly(styrene), [SiHPhCH₂]_n. Improved synthesis routes to the DSCB monomers were developed which proceed through Grignard ring closure reactions on alkoxy-substituted chlorocarbosilanes. All of these asymmetrically substituted polymers were obtained in high molecular weight form, except for [SiHPhCH₂]_n. The configurations of all of the polymers were found to be atactic. The aryl-substituted polymers have higher glass transition temperatures (T_gs) and thermal stability than those of the alkyl-substituted poly(silylenemethylene)s. Unlike the polyolefins of the type [C(H)(R)CH₂]_n, where T_g drops continuously from R = Me to n-Hex, the T_gs of the n-C_nH_2n+1 (n = 2–6)-substituted [SiMeRCH₂]_n PSM's appear to reach a maximum (at −61°C) for the R = n-Pr-substituted polymer. Moreover, where it was possible to make direct comparisons among similarly substituted atactic polymers, all of the poly(silylenemethylene)s were found to have lower T_gs than their all-carbon analogs. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3193–3205, 1997     

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     

Preparation and characterization of thermally stable poly(amide‐urea)s functionalized with anthraquinone chromophore

Two new diamines containing bulky anthraquinone pendant units were prepared via reactions of 1‐ and 2‐aminoanthraquinone with 3,5‐dinitrobenzoylchloride and a subsequent reduction of their nitro groups. A novel series of highly organosoluble poly(amide‐urea)s were synthesized from the reactions of the prepared diamines with various commercially available diisocyanates via a step‐growth addition reaction process in N‐methyl‐2‐pyrrolidone (NMP). The effects of two factors (time and temperature) on the reaction were studied to optimize the conditions for the preparation of high molecular weight polymers. All poly(amide‐urea)s were characterized by Fourier Transform Infrared (FTIR) and ¹H‐nuclear magnetic resonance (NMR) spectroscopies and elemental analysis. The resulting poly(amide‐urea)s had inherent viscosities in the range of 0.54–0.73 dl/g. They exhibited excellent solubility in polar solvents. The temperature for 10% weight loss of the polymers in air was all above 285°C, their residues were more than 36% at 700°C in air, and their T_g values were in the range of 148–190°C. According to the wide‐angle X‐ray diffraction (WAXD), the polymers were almost amorphous. The optical properties of poly(amide‐urea)s measured by ultraviolet–visible (UV–Vis) spectroscopy showed absorption maxima at 303–429 nm. Copyright © 2008 John Wiley & Sons, Ltd.     

Alternating copolymerization of carbon dioxide and cyclohexene oxide catalyzed by silicon dioxide/Zn?CoIII double metal cyanide complex hybrid catalysts with a nanolamellar structure

Air‐stable hybrid catalysts of silicon dioxide/double metal cyanide complexes (Si‐DMCCs) based on Zn₃[Co(CN)₆]₂ (ZHCC) were prepared by an in situ sol–gel method. The Si‐DMCCs showed low crystallinity and a nanolamellar structure with a thickness of ～40–60 nm. In particular, a lamellar structure of regular hexagonal shape was observed for Si‐DMCCs with low SiO₂ content. These catalysts had very high catalytic activity for alternating copolymerization of cyclohexene oxide (CHO) and carbon dioxide. A turnover number of 11,444, turnover frequency of 3815 h^?1, and apparent efficiency of 7.5 kg polymer/g ZHCC (～24.0 kg polymer/g Zn) were achieved at 3.8 MPa and 100 °C. The poly(cyclohexenylene carbonate) (PCHC) polymers obtained were completely atactic with a molecular weight (M_n) of ～10 kg/mol and polydispersity of 2.0–3.0. The PCHCs had a structure of nearly alternating CHO and CO₂ units, with a molar fraction of carbonate units of 0.44–0.47. Preliminary investigations of the mechanism suggest that nucleophilic attack by neighboring oxygen atoms is involved in copolymerization initiation with Zn? Co^III DMCCs. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3128–3139, 2008     

Thermally reversible covalently bonded linear polymers prepared from a dihalide monomer and a salt of dicyclopentadiene dicarboxylic acid

Alkali and earth‐alkali salts of dicyclopentadiene dicarboxylic acid (DCPDCA) were prepared and employed as monomers in the polyesterification with an α,ω‐dihalide monomer, such as 1,4‐dichlorobutane (DCB), 1,4‐dibromobutane (DBB), α,α′‐dichloro‐p‐xylene (DCX), and α,α′‐dibromo‐p‐xylene (DBX). Novel linear polymers that possessed repeating moieties of dicyclopentadiene ( DCPD ) in the backbone were thus prepared. The IR and NMR spectra indicated that poly(tetramethylene dicyclopentadiene dicarboxylate) (PTMDD) with a number‐average molecular weight (M_n ) of about 1× 10⁴ and poly(p‐xylene dicyclopentadiene dicarboxylate) (PXDD) with a M_n of 4–6 × 10³ were obtained with an yield of about 80% via the polyesterification of the alkali salts with DBB and DCX, respectively. The reaction was carried out in the presence of a phase transfer catalyst, such as BzMe₃NBr or poly(ethylene glycol), in DMF at 100 °C for 4 h. Oligomers with a lower M_n (1–2 × 10³) were obtained when the earth‐alkali salts were employed as salt monomers. Compared to the irreversible linear polymers, poly(p‐xylene terephthalate) (PXTP) and poly(p‐xylene maleate) (PXM), prepared through the reaction between DCX and the potassium salts of terephthalic and maleic acid, respectively, the specific viscosities (η_sp) of the new linear polymers increased abnormally with the decrease of the temperature from 200 °C to 100 °C. This occurred due to the thermally reversible dedimerization/redimerization of  DCPD moieties of the backbone of the polymers via the catalyst‐free Diels–Alder/retro Diels–Alder cycloadditive reactions. The ratio of the η_sp at 100 °C and 200 °C of the reversible polymers was found to be much higher than that of PXTP and PXM, even when the heating/cooling cycle was carried out several times under a N₂ atmosphere. The obtained results indicated that thermally reversible covalently bonded linear polymer can be obtained by introducing the  DCPD structure into the backbone of the polymer through the polymerization of a monomer containing the  DCPD moiety. The reversible natures of the polymers and oligomers might be useful in preparing easily processable and recyclable polymers and thermosensor materials. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1662–1672, 2000     

Cationic cyclopolymerization of divinyl ethers with norbornane‐, norbornene‐, or adamantane‐containing substituents: Synthesis of cyclopoly(divinyl ether)s with bulky rigid side chains leading to high glass transition temperature

Cationic cyclopolymerizations of 2,2‐bis(vinyloxymethyl)bicyclo[2.2.1]heptane ( 1 ), 5,5‐bis(vinyloxymethyl)‐2‐bicyclo[2.2.1]heptene ( 2 ), and 2,2‐bis(vinyloxymethyl)tricyclo[3.3.1.1]^{3, 7}decane ( 3 ), divinyl ethers with a norbornane, norbornene, or adamantane unit, respectively, were investigated with the HCl/ZnCl₂ initiating system in toluene and methylene chloride at ?30 °C. All the reactions proceeded quantitatively to give gel‐free, soluble polymers in organic solvents. The number‐average molecular weight (M_n) of the polymers increased in direct proportion to monomer conversion and further increased on addition of a fresh monomer feed to the almost completely polymerized reaction mixture. The contents of the unreacted vinyl groups in the produced soluble polymers were less than ～10 mol %, and therefore, the degree of cyclization of the polymers was determined to be over ～90%. These facts show that cyclopolymerization of 1 , 2 , and 3 exclusively occurred and the poly(vinyl ether)s with the cyclized repeating units and polycyclic pendants were obtained with their molecular weights being regulated. BF₃OEt₂ initiator also caused cyclopolymerization of 1 , 2 , and 3 to give the corresponding high‐molecular‐weight cyclopolymers quantitatively. Glass transition temperatures (T_g's) of poly( 1 ) and poly( 2 ) were 165–180 °C, and T_g's of poly( 3 ) were 211–231 °C; these values are very high as vinyl ether polymers. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2445–2454     

A new controllable approach to synthesize hyperbranched poly(siloxysilanes)

A new controllable approach to synthesize hyperbranched poly(siloxysilanes) via hydrosilylation of A₂‐ and B′B_x‐type monomers was developed in this work. A₂ monomers (dimethylbis(dimethylsiloxy)siloxane and tetramethyldisiloxane), B′B_x monomers (methylvinyldiallylsilane and vinyltriallylsilane), and the resultant hyperbranched poly(siloxysilanes) were well characterized using FTIR, ¹H NMR, ¹³C NMR, ²⁹Si NMR, and SEC/MALLS. The In situ FTIR results indicate that the controllable polymerization can be carried out quickly and the reaction process was obviously performed in two stages. At the first stage, silicon hydride selectively reacts with vinyl silane groups, which produces intermediate structures with one Si? H and two (or three) allyl groups. Consequently, at the second stage, these intermediates act as new AB₂ (or AB₃) type monomers and continue to be self‐polymerized to generate hyperbranched polymers. By this novel controllable approach, molecular weights and their polydispersity of the resulted hyperbranched poly(siloxysilanes) can be conveniently regulated via adjusting the process parameters, such as feeding ratio of two monomers. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2708–2720, 2008     

New organosoluble and thermally stable poly(amide‐imide)s with benzoxazole or benzothiazole pendent groups: synthesis and characterization

Two new benzoxazole or benzothiazole‐containing diimide‐dicarboxylic acid monomers, such as 2‐[3,5‐bis(N‐trimellitimidoyl)phenyl]benzoxazole ( 2 _o ) or 2‐[3,5‐bis(N‐trimellitimidoyl)phenyl]benzothiazole ( 2 _s ) were synthesized from the condensation reaction between 3,5‐diaminobenzoic acid and 2‐aminophenol or 2‐aminothiophenol in polyphosphoric acid (PPA) with subsequent reaction of trimellitic anhydride in the presence of glacial acetic acid, respectively, and two new series of modified aromatic poly(amide‐imide)s were prepared. This preparation was done with pendent benzoxazole or benzothiazole units from the newly synthesized diimide‐dicarboxylic acid and various aromatic diamines by triphenyl phosphite‐activated polycondensation. In addition, the corresponding unsubstituted poly(amide‐imide)s were prepared under identical experimental conditions for comparative purposes. Characterization of polymers was accomplished by inherent viscosity measurements, FT‐IR, UV–visible, ¹H‐NMR spectroscopy and thermogravimetry. The polymers were obtained in quantitative yields with inherent viscosities between 0.39 and 0.81 dl g^?1. The solubilities of modified poly(amide‐imide)s in common organic solvents as well as their thermal stability were enhanced compared to those of the corresponding unmodified poly(amide‐imide)s. The glass transition temperature, 10% weight loss temperature, and char yields at 800°C were, respectively, 7–26°C, 17–46°C and 2–5% higher than those of the unmodified polymers. Copyright © 2010 John Wiley & Sons, Ltd.     

Solid polymer electrolytes I,preparation, characterization,and ionic conductivity of gelled polymer electrolytes based on novel crosslinked siloxane/poly(ethylene glycol) polymers

A series of crosslinked siloxane/poly(ethylene glycol) (Si–PEG) copolymers were synthesized from the reactive methoxy‐functional silicone resin (Si resin) and PEGs with different molecular weights via two kinds of crosslinking reactions during an in situ curing stage. One of the crosslinking reactions is the self‐condensation between two methoxy groups in the Si resin, and another one is an alkoxy‐exchange reaction between the methoxy group in the Si resin and the OH group in PEG. The synthesized crosslinked copolymers were characterized by Fourier transform infrared spectroscopy, DSC, and ¹³C NMR. The crosslinked copolymers were stable in a moisture‐free environment, but the Si? O? C linkages were hydrolyzed in humid conditions. The gel‐like solid polymer electrolytes (SPEs) were prepared by impregnating these crosslinked Si–PEG copolymers in a propylene carbonate (LiClO₄/PC) solution. The highest conductivity reached 2.4 × 10^?4 S cm^?1 at 25 °C and increased to 8.7 × 10^?4 S cm^?1 at 85 °C. The conductivities of these gel‐type SPEs were affected by the content of LiClO₄/PC, the molecular weights of PEGs, and the weight fraction of the Si resin. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2051–2059, 2004     

Synthesis of hetero‐telechelic polymers by self‐polyaddition of monomers containing both oxetanyl and carboxyl groups

The synthesis and self‐polyaddition of new monomers, o‐, m‐, and p‐[(3‐ethyloxetane‐3‐yl)methoxyethyl]benzoic acid (o‐EOMB, m‐EOMB, and p‐EOMB) containing both oxetanyl groups and carboxyl groups were examined. The reactions of o‐EOMB, m‐EOMB, and p‐EOMB in the presence of tetraphenylphosphonium bromide as a catalyst in o‐dichlorobenzene at 150–170 °C resulted in self‐polyaddition to give the corresponding hetero‐telechelic polymers poly(o‐EOMB), poly(m‐EOMB), and poly(p‐EOMB) with M_ns = 14,500–33,400 in satisfactory yields. The M_n of poly(o‐EOMB) decreased at higher reaction temperatures than 150 °C, unlike those of poly(m‐EOMB) and poly(p‐EOMB), possibly due to inter‐ or intraester exchange side reactions. It was also found that the thermal properties and solubilities of these polymers were supposed with the proposed structures. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7835–7842, 2008     

Synthesis and characterization of highly fluorinated poly(phthalazinone ether)s based on AB‐type monomers

Four different fluorinated methyl‐ and phenyl‐substituted 4‐(4‐hydroxyphenyl)‐2‐(pentafluorophenyl)‐phthalazin‐1(2H)‐ones, AB‐type phthalazinone monomers, have been successfully synthesized by nucleophilic addition–elimination reactions of methyl‐ and phenyl‐substituted 2‐((4‐hydroxy)benzoyl)benzoic acid with 1‐(pentafluorophenyl)hydrazine. Under mild reaction conditions, the AB‐type monomers underwent self‐condensation polymerization reactions successfully and gave fluorinated poly(phthalazinone ether)s with high molecular weights. Detailed structural characterization of the AB‐type monomers and fluorinated polymers was determined by ¹H NMR, ¹⁹F NMR, FTIR, and GPC. The solubility, thermal properties, mechanical properties, water contact angles, and optical absorption of the polymers were evaluated. The polymers had high T_gs varying from 337 to 349 °C and decomposition temperatures (T_{d, 25} wt %) above 409 °C. Tough, flexible films were cast from THF and chloroform solutions. The films showed excellent tensile strengths ranging from 70 to 85 MPa with good hydrophobicities with water contact angles higher than 95.5 °C. The polymers had absorption edges below 340 nm and very low absorbance per cm at higher wavelengths 500–2500 nm. These results indicate that the polymers are promising as high performance materials, for example, membranes and hydrophobic materials. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1761–1770     

Fluorinated poly(arylene ether ketone)s bearing pentafluorostyrene moieties prepared by a modified polycondensation

The polycondensation of decafluorobenzophenone with hexafluorobisphenol A was modified by the addition of a molecular sieve dehydrating apparatus to the refluxing reaction system. This modification promoted the polymerization and enabled the reactions to be conducted in milder conditions and completed in a shorter time, thereby depressing side reactions such as branching and crosslinking. The resulting fluorinated poly(arylene ether ketone)s (FPAEK) were free of gel particles and possessed the designed molecular weights. This modified procedure was also suitable for introducing crosslinkable pentafluorostyrene (FSt) moieties into the polymers at the chain ends and/or inside the chain with the vinyl group of FSt being pendant. The resulting FSt containing fluorinated poly(arylene ether ketone)s (FPAEK‐FSt) can then be thermally crosslinked at 100 °C in the presence of 1% benzoyl peroxide (BPO) or at 250 °C without any initiator. The glass‐transition temperatures (T_g's) of FPAEK increased with increasing molecular weight and leveled off at about 147 °C for the polymer with a number‐average molecular weight of 18,600 Da, whereas the values were not apparently affected by the addition of FSt units. However, crosslinking of the FPAEK‐FSt resulted in an approximate 30 °C increase of the T_g. Spin‐coating FPAEK‐FSt onto silicon wafers followed by crosslinking gave films with excellent thermal stability, physical strength, and adhesion to the substrate as well as good reproducibility in terms of film preparation and optical properties. The refractive index and birefringence of the films measured at a wavelength of 1.55 μm were 1.502 and 2.5 × 10^?3, respectively. © 2002 Government of Canada. Exclusive worldwide publication rights in the article have been transferred to Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4205–4216, 2002     

Star‐shaped cyclopolymers: A new category of star polymer with rigid cyclized arms prepared by controlled cationic cyclopolymerization and subsequent microgel formation of divinyl ethers

The combination of living/controlled cationic cyclopolymerization and crosslinking polymerization of bifunctional vinyl ethers (divinyl ethers) was applied to the synthesis of core‐crosslinked star‐shaped polymers with rigid cyclized arms. Cyclopolymerization of 4,4‐bis(vinyloxymethyl)cyclohexene ( 1 ), a divinyl ether with a cyclohexene group, was investigated with the hydrogen chloride/zinc chloride (HCl/ZnCl₂) initiating system in toluene at 0 °C. The reaction proceeded quantitatively to give soluble poly( 1 )s in organic solvents. The content of the unreacted vinyl groups in the produced polymers was less than ～3 mol%, and therefore, the degree of cyclization of the polymers was determined to be ～97%. The number‐average molecular weight (M_n) of the polymers increased in direct proportion to monomer conversion and further increased on addition of a fresh monomer feed to the almost completely polymerized reaction mixture, indicating that living cyclopolymerization of 1 occurred. The chain linking reactions among the formed living cyclopolymers with 1,4‐bis(vinyloxy)cyclohexane ( 3 ) as a crosslinker in toluene at 0 °C produced core‐crosslinked star‐shaped cyclopoly( 1 )s [star‐poly( 1 )s] in high yield (100%). Dihydroxylation of the cyclohexene double bonds of star‐poly( 1 ) gave hydrophilic water‐soluble star‐shaped polymers with rigid arm structure [star‐poly( 1 )‐OH] with thermo‐responsive function in water. T_gs of star‐poly( 1 ) and star‐poly( 1 )‐OH were 135 °C and 216 °C, respectively; these values are very high as vinyl ether‐based star‐shaped polymers. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 1094–1102     

New P‐type of poly(4‐methoxy‐triphenylamine)s derived by coupling reactions: Synthesis,electrochromic behaviors,and hole mobility

Methoxy‐substituted poly(triphenylamine)s, poly‐4‐methoxytriphenylamine ( PMOTPA ), and poly‐N,N‐bis(4‐methoxyphenyl)‐N′,N′‐diphenyl‐p‐phenylenediamine ( PMOPD ), were synthesized from the nickel‐catalyzed Yamamoto and oxidative coupling reaction with FeCl₃. All synthesized polymers could be well characterized by ¹H and ¹³C NMR spectroscopy. These polymers possess good solubility in common organic solvent, thermal stability with relatively high glass‐transition temperatures (T_gs) in the range of 152–273 °C, 10% weight‐loss temperature in excess of 480 °C, and char yield at 800 °C higher than 79% under a nitrogen atmosphere. They were amorphous and showed bluish green light (430–487 nm) fluorescence with quantum efficiency up to 45–62% in NMP solution. The hole‐transporting and electrochromic properties are examined by electrochemical and spectroelectrochemical methods. All polymers exhibited reversible oxidation redox peaks and E_onset around 0.44–0.69 V versus Ag/AgCl and electrochromic characteristics with a color change under various applied potentials. The series of PMOTPA and PMOPD also showed p‐type characteristics, and the estimated hole mobility of O ‐ PMOTPA and Y ‐ PMOPD were up to 1.5 × 10^?4 and 5.6 × 10^?5 cm² V^?1 s^?1, respectively. The FET results indicate that the molecular weight, annealing temperature, and polymer structure could crucially affect the charge transporting ability. This study suggests that triphenylamine‐containing conjugated polymer is a multifunctional material for various optoelectronic device applications. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4037–4050, 2009     

Synthesis of poly(1‐chloro‐2‐arylacetylene)s with high cis‐content and examination of their absorption/emission properties

A series of 1‐chloro‐2‐arylacetylenes [Cl‐C?C‐Ar, Ar = C₆H₅ ( 1 ), C₆H₄‐p‐i Pr ( 2 ), C₆H₄‐p‐Oi Pr ( 3 ), C₆H₄‐p‐NHC(O)Ot Bu ( 4 ), and C₆H₄‐o‐i Pr ( 5 )] were polymerized using (tBu₃P)PdMeCl/silver trifluoromethanesulfonate (AgOTf) and MoCl₅/SnBu₄ catalysts. The corresponding polymers [poly( 1 )–poly( 5 )] with weight‐average molecular weights of 6,500–690,000 were obtained in 10–91% yields. THF‐insoluble parts, presumably high‐molecular weight polymers, were formed together with THF‐soluble polymers by the Pd‐catalyzed polymerization. The Pd catalyst polymerized nonpolar monomers 1 and 2 to give the polymers in yields lower than the Mo catalyst, while the Pd catalyst polymerized polar monomers 3 and 4 to give the corresponding polymers in higher yields. The ¹H NMR and UV–vis absorption spectra of the polymers indicated that the cis‐contents of the Pd‐based polymers were higher than those of the Mo‐based polymers, and the conjugation length of the Pd‐based polymers was shorter than that of the Mo‐based polymers. Pd‐based poly( 5 ) emitted fluorescence most strongly among poly( 1 )–poly( 5 ). © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55 , 382–388     

Dehydrocoupling and Diels–Alder reactions on siloxane polymers

Dehydrocoupling reactions between linear poly(methylhydrosiloxane) {Me₃SiO–[MeSi(H)O]_n–SiMe₃} and alcohols such as cholesterol, anthracene‐9‐carbinol, (12‐crown‐4)‐2‐carbinol, pyrene‐1‐carbinol, 4‐methyl‐5‐thiazoleethanol, and 4‐pyridilpropanol were introduced under catalytically mild conditions. The degrees of conversion of Si? H bonds in polysiloxane were monitored with ¹H NMR spectra. The reaction of the 9‐methoxyanthracene adduct on siloxane polymers and maleimide derivatives (maleimide, N‐ethylmaleimide, and maleic acid anhydride) produced [2+4]‐cycloadducts in very high yields. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 4013–4019, 2002     

One‐pot synthesis and characterization of hyperbranched poly(ester‐amide)s from commercially available dicarboxylic acids and multihydroxyl secondary amines

A convenient and cost‐effective strategy for synthesis of hyperbranched poly(ester‐amide)s from commercially available dicarboxylic acids (A₂) and multihydroxyl secondary amine (CB₂) has been developed. By optimizing the conditions of model reactions, the AB₂‐type intermediates were formed dominantly during the initial reaction stage. Without any purification, the AB₂ intermediate was subjected to thermal polycondensation in the absence of any catalyst to prepare the aliphatic and semiaromatic hyperbranched poly(ester‐amide)s bearing multi‐hydroxyl end‐groups. The FTIR and ¹H NMR spectra indicated that the polymerization proceeded in the proposed way. The DBs of the resulting polymers were confirmed by a combination of inverse‐gated decoupling ¹³C NMR, and DEPT‐135 NMR techniques. The DBs of the hyperbranched poly(ester‐amide)s were in the range of 0.44–0.73, depending on the structure of the monomers used. The hyperbranched polymers exhibited moderate molecular weights with relatively broad distributions determined by SEC. All the polymers displayed low inherent viscosity (0.11–0.25 dL/g) due to the branched nature. Structural and end‐group effects on the thermal properties of the hyperbranched polymers were investigated using DSC. The thermogravimetric analysis revealed that the resulting polymers exhibit reasonable thermal stability. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5077–5092, 2008     

Synthesis and polymerization of new self‐polymerizable quinoxaline monomers

Extended self‐polymerizable poly(phenylquinoxaline) monomer mixtures {i.e.,2‐[4‐(4‐hydroxyphenoxy)phenyl]‐3‐phenyl‐6‐chloroquinoxaline and 3‐[4‐(4‐hydroxy phenoxy)phenyl]‐2‐phenyl‐6‐chloroquinoxaline, 2‐[4‐(4‐hydroxyphenoxy)phenyl]‐3‐phenyl‐6‐fluoroquinoxaline and 3‐[4‐(4‐hydroxyphenoxy)phenyl]‐2‐phenyl‐6‐fluoroquinoxaline, and 2‐(4‐fluorophenyl)‐3‐phenyl‐6‐(4‐hydroxyphenoxy)quinoxaline and 3‐(4‐fluorophenyl)‐2‐phenyl‐6‐(4‐hydroxyphenoxy)quinoxaline} more flexible and nucleophilic than a previously reported monomer mixture [i.e., 3‐(4‐hydroxyphenyl)‐2‐phenyl‐6‐fluoroquinoxaline and 2‐(4‐hydroxyphenyl)‐3‐phenyl‐6‐fluoroquinoxaline] were synthesized. The monomer mixtures were then polymerized into high‐molecular‐weight polymers. A sample was obtained, through a chlorine displacement reaction, that was a semicrystalline polymer with an intrinsic viscosity of 1.11 dL/g in m‐cresol at 30 ± 0.1 °C and two melting temperatures at 339 and 377 °C in the first differential scanning calorimetry scan. There was a melting temperature at 328 °C without a detectable glass‐transition temperature (T_g) when the sample was subjected to a second differential scanning calorimetry scan. The samples from fluorine displacement reactions were completely amorphous polymers. They had intrinsic viscosities of 0.53–0.90 dL/g in m‐cresol at 30 ± 0.1 °C and T_g's of 220–224 °C. The polymer samples from fluorine displacement reactions were evaluated with gel permeation chromatography and matrix‐assisted laser desorption/ionization time‐of‐flight analyses, which monitored the existence of certain amounts of cyclic oligomers. The thin films of the polymers had room‐temperature tensile strengths of 97–113 MPa, room‐temperature Young's moduli of 2.30–2.35 GPa, and room‐temperature elongations at break of 40–150%. The melt viscosity decreased from 10⁷ to less than 10⁴ Pa s at 310 °C as the frequency was increased from 10^?2 to 10² rad/s. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 78–91, 2005