Preparation of new π‐conjugated polypyrroles by organometallic polycondensations. Synthesis of N‐BOC (t‐butoxycarbonyl) and N‐phenylethynyl polymers,thermal deprotection of the BOC Group,and packing structure of the N‐phenylethynyl polymer

New π–conjugated polypyrroles such as poly(3‐heptyl‐N‐(t‐butoxycarbonyl)pyrrole‐2,5‐diyl), PPr(3‐Hep; N‐BOC) , and poly(N‐(phenylethynyl)pyrrole‐2,5‐diyl‐alt‐thiophene‐2,5‐diyl), Copoly‐2 , were prepared by organometallic polycondensations using the corresponding 2.5‐dihalopyrroles as the starting materials. Deprotection of the BOC group of PPr(3‐Hep; N‐BOC) proceeded at 185 °C to give poly(3‐heptylpyrrole). XRD (X‐ray diffraction) data of Copoly‐2 indicated that Copoly‐2 assumed a stacked structure in the solid. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6223–6232, 2005     

Preparation,characterization, and thermal properties of alt‐copoly[1,9‐decaphenylpentasiloxanylene/1,3‐bis(ethylene)permethyloligosiloxanylene]s

alt‐Copoly[1,9‐decaphenylpentasiloxanylene/1,3‐bis(ethylene)tetramethyldisiloxanylene], alt‐copoly[1,9‐decaphenylpentasiloxanylene/1,5‐bis(ethylene)hexamethyltrisiloxanylene], alt‐copoly[1,9‐decaphenylpentasiloxanylene/1,7‐bis(ethylene)octamethyltetrasiloxanylene], and alt‐copoly[1,9‐decaphenylpentasiloxanylene/1,9‐bis(ethylene)decamethylpentasiloxanylene] were synthesized by Pt‐catalyzed hydrosilylation reactions of 1,9 divinyldecaphenylpentasiloxanes with a series of oligodimethylsiloxanes. The molecular weights of these copolymers were determined by gel permeation chromatography. Their glass‐transition temperatures (T_g's) were obtained by differential scanning calorimetry. The thermal stabilities of the copolymers were measured by thermogravimetric analysis. The structures of the copolymers were verified by ¹H, ¹³C, and ²⁹Si NMR as well as IR and UV spectroscopy. The copolymers displayed high thermal stabilities and a single T_g, indicating that phase separation between the two short blocks did not occur. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6146–6152, 2005     

Oligo(p‐phenyleneethynylene)‐based coil–rod–coil triblock copolymer: Synthesis and controlled self‐organization in solution

The self‐assembling ability of block copolymers offers an attractive strategy for the organization of π‐conjugated polymers. This article reports the synthesis of a coil–rod–coil triblock copolymer consisting of oligo(p‐phenyleneethynylene) as the rodlike segment and polystyrene as the coil‐like segment. The chemical structure of the afforded triblock copolymer has been fully characterized by various spectroscopic techniques such as NMR, Raman, gel permeation chromatography, differential scanning calorimetry, ultraviolet–visible, and fluorescence spectroscopy. The small‐angle neutron scattering and photophysical measurements indicate that this triblock copolymer exhibits unique solvatochromatic behaviors through the interplay of aggregation‐induced π–π stacking and planarization of the conjugated backbone. Supramolecular gel nanostructures have been produced via the controlled assembly of the polymer into H‐aggregates. It has been demonstrated that the use of the solvent composition to influence chain conformations and thus to manipulate the packing of the conjugated polymer blocks is important for achieving control in the assembly of conducting polymers and associated optical characteristics. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 6007–6019, 2005     

Concentration effects in the cationic ring‐opening polymerization of 2‐ethyl‐2‐oxazoline in N,N‐dimethylacetamide

The monomer concentration for the cationic ring‐opening polymerization of 2‐ethyl‐2‐oxazoline in N,N‐dimethylacetamide was optimized utilizing high‐throughput experimentation methods. Detailed ¹H‐NMR spectroscopic investigations were performed to understand the mechanistic aspects of the observed concentration effects. Finally, the improved polymerization concentration was applied for the synthesis of higher molecular weight (> 10,000 Da) poly(2‐ethyl‐2‐oxazoline)s. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1487–1497, 2005     

Studies on the modification of poly(ω‐bromoalkyl‐1‐glycidylether)s with 4′‐methoxybiphenyl‐4‐oxy mesogenic groups

A series of poly[ω‐(4′‐methoxy‐biphenyl‐4‐oxy)alkyl‐1‐glycidylether]s were synthesized by chemically modifying the corresponding poly(ω‐bromoalkyl‐1‐glycidylether)s with the sodium salt of 4‐hydroxy‐4′‐methoxybiphenyl. New high‐molecular‐weight side‐chain liquid‐crystalline polymers were obtained with excellent yields and almost quantitative degrees of modification. They were all insoluble in THF and other common solvents. Characterization by ¹³C NMR confirmed that all the polymers had the expected structure. The liquid crystalline behavior of the polymers was analyzed by DSC and polarized optical microscopy, and mesophase assignments were confirmed by X‐ray diffraction studies. Polymers that had alkyl spacers with n = 2 and 4 were smectic C, those that had spacers with n = 6 and 8 were nematic cybotactic, and those that had longer spacers (n = 10 and 12) were smectic C again. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5998–6006, 2005     

New poly(oxyethylene) derivatives and their oligo analogues from Diels–Alder reactions of 5‐[methoxypoly(oxyethylene)]‐(3E)‐1, 3‐pentadiene and 5‐methoxyethoxy‐(3E)‐1,3‐pentadiene

Diels–Alder reactions of 5‐[methoxypoly(oxyethylene)]‐(3E)‐1,3‐pentadiene ( 1a ) with maleic anhydride, diethyl acetylenedicarboxylate (DADC), and acrolein were investigated for the synthesis of new poly(ethylene glycol) derivatives. To facilitate the characterization of the derivatives, Diels–Alder reactions of 5‐methoxyethoxy‐(3E)‐1,3‐pentadiene ( 1b ) with the aforementioned dienophiles were also studied. The reaction of o‐toluidine with the cycloaddition product from maleic anhydride and 1b resulted in the corresponding amide products. The reactions of 2,3‐dichloro‐5,6‐dicyano‐1,4‐benzoquinone with cycloadducts derived from 1a and 1b with DADC resulted in the aromatization of the corresponding products. An NMR analysis of the adducts obtained from 1a and acrolein in water and from 1b and acrolein in water/acetonitrile (4:1 v/v) indicated a mixture of endo and exo, with the endo concentration being approximately 80%. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1895–1902, 2005     

Oxazoline‐terminated macromonomers by the alkylation of 2‐methyl‐2‐oxazoline

Well‐defined macromonomers of poly(ethylene oxide) and poly(tert‐butyl methacrylate) were obtained by anionic polymerization induced directly by the carbanion issued from 2‐methyl‐2‐oxazoline. When ethylene oxide was added to this carbanion with lithium as the counterion, a new compound able to initiate the polymerization of ε‐caprolactone in an anionically coordinated way was synthesized, and this led to well‐defined poly(ε‐caprolactone) macromonomers. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2440–2447, 2005     

Tacticity of poly‐α‐olefins from poly‐1‐hexene to poly‐1‐octadecene

A systematic study of the influence of the α‐olefin size, the catalyst stereospecificity and the reaction temperature was done on the catalytic activity and tacticity of poly‐α‐olefins from 1‐hexene to 1‐octadecene. The metallocenes used were rac‐Et[Ind₂]ZrCl₂ ( 1 ) and Me₂C[Cp(9‐Flu)]ZrCl₂ ( 2 ) to obtain isotactic and syndiotactic polyolefins. Some catalysts giving atactic polymers were also used in order to study all the possible ¹³C NMR pentades. Catalytic activities increased and isotacticity and syndiotacticity decreased with temperature, but no real trend was found with the α‐olefin size. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4744–4753, 2005     

Modular synthesis of polymers containing 2,5‐di(thiophenyl)‐N‐arylpyrrole

A modular and facile route has been developed to synthesize functionalized 2,5‐di(thiophen‐2‐yl)‐1‐H‐arylpyrroles from readily available starting materials. These units are compatible with various polymerization conditions and are versatile building blocks for conjugated polymers. The polymers show high thermal stability and solubility in a number of solvents. Characterization of the polymers reveals a correlation between molecular packing, controllable by polymer design, and charge carrier mobility. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018 , 56, 1133–1139     

Water‐soluble poly(ethylene oxide)‐block‐poly(p‐phenylene vinylene) copolymer: Synthesis and characterization

Water‐soluble and photoluminescent block copolymers [poly(ethylene oxide)‐block‐poly(p‐phenylene vinylene) (PEO‐b‐PPV)] were synthesized, in two steps, by the addition of α‐halo‐α′‐alkylsulfinyl‐p‐xylene from activated poly(ethylene oxide) (PEO) chains in tetrahydrofuran at 25 °C. This copolymerization, which was derived from the Vanderzande poly(p‐phenylene vinylene) (PPV) synthesis, led to partly converted PEO‐b‐PPV block copolymers mixed with unreacted PEO chains. The yield, length, and composition of these added sequences depended on the experimental conditions, namely, the order of reagent addition, the nature of the monomers, and the addition of an extra base. The addition of lithium tert‐butoxide increased the length of the PPV precursor sequence and reduced spontaneous conversion. The conversion into PPV could be achieved in a second step by a thermal treatment. A spectral analysis of the reactive medium and the composition of the resulting polymers revealed new evidence for an anionic mechanism of the copolymerization process under our experimental conditions. Moreover, the photoluminescence yields were strongly dependant on the conjugation length and on the solvent, with a maximum (70%) in tetrahydrofuran and a minimum (<1%) in water. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4337–4350, 2005     

Dependence of the luminescent properties and chain length of poly[2‐methoxy‐5‐(2′‐ethyl‐hexyloxy)‐1,4‐phenylene vinylene] on the formation of cis‐vinylene bonds during Gilch polymerization

The presence of cis‐vinylene bonds in Gilch‐polymerized poly[2‐methoxy‐5‐(2′‐ethyl‐hexyloxy)‐1,4‐phenylene vinylene] is reported. Through fractionation, species with a weight‐average molecular weight of less than 37,000 exhibited an abnormal blueshift of photoluminescence spectra in toluene solutions, and this was attributed to the presence of cis‐vinylene bonds, as verified by NMR spectroscopy. Surprisingly, the fractionated species (～1 wt %) with a weight‐average molecular weight of 5000 were mostly linked by the cis‐vinylene bonds. The concentration decreased with the molecular weight until a molecular weight of 37,000 was reached; at that point, the polymer chains contained mainly trans‐vinylene bonds. Obviously, the formation of cis‐vinylene bonds strongly inhibited the growth of polymer chains during Gilch polymerization. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2520–2526, 2005     

Antimicrobial polymers containing melamine derivatives. II. Biocidal polymers derived from 2‐vinyl‐4,6‐diamino‐1,3,5‐triazine

Poly(2‐vinyl‐4,6‐diamino‐1,3,5‐triazine) (PVDAT) and a series of poly(styrene‐co‐2‐vinyl‐4,6‐diamino‐1,3,5‐triazine) (PS‐co‐VDAT) copolymers were synthesized via conventional free‐radical polymerizations. The polymer structures were confirmed by Fourier transform infrared, NMR, and elemental analysis. The molecular weights were determined by gel permeation chromatography studies, and the thermal properties were characterized by differential scanning calorimetry and thermogravimetric analysis. After treatment with chlorine bleach, PVDAT and PS‐co‐VDAT provided potent antimicrobial functions against multidrug‐resistant Gram‐negative and Gram‐positive bacteria. The antimicrobial functions were durable for longer than 3 months and rechargeable for more than 50 times. The structure–property relationship of the polymers was further discussed. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4089–4098, 2005     

Synthesis of poly(2‐vinyl pyridine)‐b‐poly(n‐hexyl isocyanate) amphiphilic coil‐rod block copolymer by anionic polymerization

A well‐defined amphiphilic coil‐rod block copolymer, poly(2‐vinyl pyridine)‐b‐poly(n‐hexyl isocyanate) (P2VP‐b‐PHIC), was synthesized with quantitative yields by anionic polymerization. A low reactive one‐directional initiator, potassium diphenyl methane (DPM‐K), was very effective in polymerizing 2‐vinyl pyridine (2VP) without side reactions, leading to perfect control over molecular weight and molecular weight distribution over a broad range of initiator and monomer concentration. Copolymerization of 2VP with n‐hexyl isocyanate (HIC) was carried out in the presence of sodium tetraphenyl borate (NaBPh₄) to prevent backbiting reactions during isocyanate polymerization. Terminating the living end with a suitable end‐capping agent resulted in a P2VP‐b‐PHIC coil‐rod block copolymer with controlled molecular weight and narrow molecular weight distribution. Cast film from a chloroform solution of P2VP‐b‐PHIC displayed microphase separation, characteristic of coil‐rod block copolymers. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 607–615, 2005     

Atom transfer radical polymerization of sodium2‐acrylamido‐2‐methylpropanesulfonate

The first example of well‐controlled atom transfer radical polymerization (ATRP) of a permanently charged anionic acrylamide monomer is reported. ATRP of sodium 2‐acrylamido‐2‐methylpropanesulfonate (NaAMPS) was achieved with ethyl 2‐chloropropionate (ECP) as an initiator and the CuCl/CuCl₂/tris(2‐dimethylaminoethyl)amine (Me₆TREN) catalytic system. The polymerizations were carried out in 50:50 (v/v) N,N‐dimethylformamide (DMF)/water mixtures at 20 °C. Linear first‐order kinetic plots up to a 92% conversion for a target degree of polymerization of 50 were obtained with [ECP]/[CuCl]/[CuCl₂]/[Me₆TREN] = 1:1:1:2 and [AMPS] = 1 M. The molecular weight increased linearly with the conversion in good agreement with the theoretical values, and the polydispersities decreased with increasing conversion, reaching a lower limit of 1.11. The living character of the polymerization was confirmed by chain‐extension experiments. Block copolymers with N,N‐dimethylacrylamide and N‐isopropylacrylamide were also prepared. The use of a DMF/water mixed solvent should make possible the synthesis of new amphiphilic ionic block copolymers without the use of protecting group chemistry. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4446–4454, 2005     

Synthesis and characterization of polyimides derived from (3‐amino‐2,4,6‐trimethylphenyl)‐(3′‐aminophenyl)methanone and aromatic dianhydrides

A series of new polyimides were prepared via the polycondensation of (3‐amino‐2,4,6‐trimethylphenyl)‐(3′‐aminophenyl)methanone and aromatic dianhydrides, that is, 3,3′,4,4′‐biphenyltetracarboxylic dianhydride (BPDA), 4,4′‐oxydiphthalic anhydride, 3,3′,4,4′‐benzophenone tetracarboxylic dianhydride, and 2,2′‐bis(3,4‐dicarboxyphenyl) hexafluoropropane dianhydride. The structures of the polyimides were characterized by Fourier transform infrared and NMR measurements. The properties were evaluated by solubility tests, ultraviolet–visible analysis, differential scanning calorimetry, and thermogravimetric analysis. The two different meta‐position‐located amino groups with respect to the carbonyl bridge in the diamine monomer provided it with an unsymmetrical structure. This led to a restriction on the close packing of the resulting polymer chains and reduced interchain interactions, which contributed to the solubility increase. All the polyimides except that derived from BPDA had good solubility in strong aprotic solvents, such as N‐methyl‐2‐pyrrolidinone, N,N′‐dimethylacetamide, N,N‐dimethylformamide, and dimethyl sulfone, and in common organic solvents, such as cyclohexanone and chloroform. In addition, these polyimides exhibited high glass‐transition values and excellent thermal properties, with an initial thermal decomposition temperature above 470 °C and glass‐transition temperatures in the range of 280–320 °C. The polyimide films also exhibited good transparency in the visible‐light region, with transmittance higher than 80% at 450 nm and a cutoff wavelength lower than 370 nm. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 1291–1298, 2006     

Cationic polymerization of seven‐membered cyclic monothiocarbonate 1,3‐dioxepan‐2‐thione

The cationic ring‐opening polymerization of a seven‐membered cyclic monothiocarbonate, 1,3‐dioxepan‐2‐thione, produced a soluble polymer through the selective isomerization of thiocarbonyl to a carbonyl group {? [SC(C?O)O(CH₂)₄]_n? }. The molecular weights of the polymer could be controlled by the feed ratio of the monomer to the initiators or the conversion of the monomer during the polymerization, although some termination reactions occurred after the complete consumption of the monomer. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1014–1018, 2005     

Multifunctional,water‐soluble,C60‐pendant maleic anhydride copolymer

Starting from the synthesis of a new methanofullerene derivative bearing an alcohol group, we report on the preparation of a water‐soluble, fullerene‐pendant copolymer. This multifunctional, C₆₀‐pendant maleic anhydride copolymer was characterized by conductometric titration, Fourier transform infrared and ultraviolet spectroscopy, thermogravimetric analysis, and cyclic voltammetry. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 5814–5822, 2005     

Reversible addition–fragmentation chain transfer polymerization of 2‐naphthyl acrylate with 2‐cyanoprop‐2‐yl 1‐dithionaphthalate as a chain‐transfer agent

The reversible addition–fragmentation chain transfer (RAFT) polymerizations of 2‐naphthyl acrylate (2NA) initiated by 2,2′‐azobisisobutyronitrile were investigated with 2‐cyanoprop‐2‐yl 1‐dithionaphthalate (CPDN) as a RAFT agent at various temperatures in a benzene solution. The results of the polymerizations showed that 2NA could be polymerized in a controlled way by RAFT polymerization with CPDN as a RAFT agent; the polymerization rate was first‐order with respect to the monomer concentration, and the molecular weight increased linearly with the monomer conversion. The polydispersities of the polymer were relatively low up to high conversions in all cases. The chain‐extension reactions of poly(2‐naphthyl acrylate) (P2NA) with methyl methacrylate and styrene successfully yielded poly(2‐naphthyl acrylate)‐b‐poly(methyl methacrylate) and poly(2‐naphthyl acrylate)‐b‐polystyrene block polymers, respectively, with narrow polydispersities. The P2NA obtained by RAFT polymerization had a strong ultraviolet absorption at 270 nm, and the molecular weights had no apparent effect on the ultraviolet absorption intensities; however, the fluorescence intensity of P2NA increased as the molecular weight increased and was higher than that of 2NA. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2632–2642, 2005     

Synthesis and characterization of novel biodegradable block copolymer poly(ethylene glycol)‐block‐poly(L‐lactide‐co‐2‐methyl‐2‐carboxyl‐propylene carbonate)

An amphiphilic block copolymer, poly(ethylene glycol)‐block‐poly(L ‐lactide‐co‐2‐methyl‐2‐benzoxycarbonyl‐propylene carbonate) [PEG‐b‐P(LA‐co‐MBC)], was synthesized in bulk by the ring‐opening polymerization of L ‐lactide with 2‐methyl‐2‐benzoxycarbonyl‐propylene carbonate (MBC) in the presence of poly(ethylene glycol) as a macroinitiator with diethyl zinc as a catalyst. The subsequent catalytic hydrogenation of PEG‐b‐P(LA‐co‐MBC) with palladium hydroxide on activated charcoal (20%) as a catalyst was carried out to obtain the corresponding linear copolymer poly(ethyleneglycol)‐block‐poly(L ‐lactide‐co‐2‐methyl‐2‐carboxyl‐propylenecarbonate) [PEG‐b‐P(LA‐co‐MCC)] with pendant carboxyl groups. DSC analysis indicated that the glass‐transition temperature (T_g) of PEG‐b‐P(LA‐co‐MBC) decreased with increasing MBC content in the copolymer, and T_g of PEG‐b‐P(LA‐co‐MCC) was higher than that of the corresponding PEG‐b‐P(LA‐co‐MBC). The in vitro degradation rate of PEG‐b‐P(LA‐co‐MCC) in the presence of proteinase K was faster than that of PEG‐b‐P(LA‐co‐MBC), and the cytotoxicity of PEG‐b‐P(LA‐co‐MCC) to chondrocytes from human fetal arthrosis was lower than that of poly(L ‐lactide). © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 4771–4780, 2005     

Preparation and characterization of biodegradable poly(trimethylenecarbonate‐ε‐caprolactone)‐block‐poly(p‐dioxanone) copolymers

A series of poly(trimethylenecarbonate‐ε‐caprolactone)‐block‐poly(p‐dioxanone) copolymers were prepared with varying feed rations by using two step polymerization reactions. Poly(trimethylenecarbonate)(ε‐caprolactone) random copolymer was synthesized with stannous‐2‐ethylhexanoate and followed by adding p‐dioxanone monomer as the other block. The ring opening polymerization was carried out at high temperature and long reaction time to get high molecular weight polymers. The monofilament fibers were obtained using conventional melting spun methods. The copolymers were identified by ¹H and ¹³C NMR spectroscopy and gel permeation chromatography (GPC). The physicochemical properties, such as viscosity, molecular weight, melting point, glass transition temperature, and crystallinity, were studied. The hydrolytic degradation of copolymers was studied in a phosphate buffer solution, pH = 7.2, 37 °C, and a biological absorbable test was performed in rats. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2790–2799, 2005