Synthesis,characterization, and pyrolysis of ferrocenyl unit containing organosilicon polymers

New polyferrocenylsiloxanes (PFSXs) and polyferrocenylsilazanes (PFSZs) with linear or linear‐cyclic structure were prepared. The ceramic yields of the polymers were estimated by thermogravimetric analysis (TGA) and bulk pyrolysis, which closely depend on molecular structures. Compared with that of their linear counterparts having comparable molecular weights, the ceramic yields of linear‐cyclic PFSX and PFSZ were much higher. The pyrolysis process was investigated by lysis character is (TGA) highly depend on their molecular weights and structures, infrared spectra, and pyrolysis‐gas chromatography‐mass spectra (Py‐GC‐MS) analysis. The results indicated rather amount of ferrocene‐based small molecules were formed during the pyrolysis of linear polymers in the range of 25–300°C, whereas the existence of crosslinking or branched structure in the linear‐cyclic polymers prohibited this transformation, and therefore, dramatically improved the ceramic yields. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis and characterization of fluorene-based electroluminescent polymers containing silyl groups

Summary Two types of fluorene-based copolymers, poly(9,9'-di-n-hexyl-2,7-fluorenediyl-ethynylene-alt-9-trimethylsilyl-2,7-fluoreneethynylene[P-1], poly(9,9-di-n-hexyl-2,7-fluorenediylethynylene-alt-9,9'-bis-trimethylsilyl-2,7-fluoreneethynylene[P-2] were synthesized by employing palladium catalyzed polycondensation. Resulting polymers showed a good solubility in various organic solvents such as THF, chloroform, dioxane etc. and could be easily spin-coated onto an ITO glass plate to make a fine thin film. Characterization of these polymers includes FT-IR, UV-vis., ¹H and ¹³C-NMR, was conducted. Thermal properties were also investigated by DSC and TGA as well as molecular weight studies. The present polymers exhibited emission of blue-white color. The photoluminescence (PL) spectrum of the polymers showed two peaks at 490 and 540 nm and it was found that electroluminescence (EL) spectra of the polymer [P-2] was very similar to its PL spectrum. Received: 17 September 2001/ Accepted: 12 October 2001     

Synthesis and characterization of novel aromatic condensation polymers containing rigid benzoxazole pendent groups

A new aromatic diamine monomer containing benzoxazole substituents was prepared by a multistep synthesis starting from 1,4‐dibromo‐2,5‐difluorobenzene. The diamine was polymerized with commercial aromatic dianhydride or dicarboxylic acid chloride monomers to provide several different poly(amic acid)s and polyamides with their inherent viscosities in the range of 0.24–0.46 dL/g. Thermal properties of these polymers including thermal imidization of poly(amic acid)s into polyimides were investigated by using FTIR, DSC, and TGA. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 178–185, 2004     

氨丙基苯基有机硅树脂微粉的合成与表征

在四甲基氢氧化铵(TMAOH)水溶液的催化作用下,将苯基三乙氧基硅烷(PTES)、γ-氨丙基三乙氧基硅烷(APS)和二苯基二甲氧基硅烷(DDS)进行水解共缩聚制备氨丙基苯基有机硅树脂微粉。探讨了反应物PTES、APS、DDS三者的比例、TMAOH的用量、反应温度、搅拌速率及反应物加入方式对反应的影响,通过傅里叶变换红外光谱、核磁共振、热重分析法表征了产物的结构。结果表明,制备白色氨丙基苯基有机硅树脂微粉的较佳条件:TMAOH(以水为基准)的质量分数为0·2%~0·4%,APS/(DDS PTES)(摩尔比)为0·35~2·00,PTES/DDS(摩尔比)为1·8,反应温度为20℃,搅拌速率为300r/min,且采用逐滴加料的方法;PTES、APS、DDS三者之间发生了共缩聚反应。     

Synthesis and characterization of hydrogels containing biodegradable polymers

BACKGROUND: Amphiphilic block and graft copolymers constitute a very interesting class of polymers with potential for biomedical applications, due to their special characteristics, which derive from the combination of properties of hydrophilic and hydrophobic moieties. In this work, the synthesis and biodegradation of poly(2‐hydroxyethyl methacrylate)‐graft‐poly(L ‐lactide) are studied. RESULTS: The graft copolymers were synthesized using the macromonomer technique. In a first step, methacryloyl‐terminated poly(L ‐lactide) macromonomers were synthesized in a wide molecular weight range using different catalysts. Subsequently, these macromonomers were copolymerized with 2‐hydroxyethyl methacrylate in order to obtain a graft copolymer. These new materials resemble hydrogel scaffolds with a biodegradable component. The biodegradation was studied in hydrolytic and enzymatic environments. The influence of different parameters (molecular weight, crystallinity, ratio between hydrophilic and hydrophobic components) on the degradation rate was investigated. CONCLUSION: Based on this study it will be possible to tailor the release properties of biodegradable materials. In addition, the materials will show good biocompatibility due to the hydrophilic poly(2‐hydroxyethyl methacrylate) hydrogel scaffold. This kind of material has potential for many applications, like controlled drug‐delivery systems or biodegradable implants. Copyright © 2008 Society of Chemical Industry     

Synthesis, characterization and use of reactive polymers with diisopropylphenylphosphine groups

The synthesis of linear and crosslinked polymers starting with 4-(diisopropyl-phosphinyl) styrene is described. Treatment with triphosgene yields the corresponding phosphine dichloride group in the polymers. Using these reactive polymers benzyl alcohol was converted to benzyl chloride at room temperature. The regeneration of the reactive polymers using triphosgene was achieved. The yields of benzyl chloride were in general lower than those previously reported using triphenylphosphine dichloride groups in the polymers. The difference in reactivity between triphenylphosphine dichloride- and diisopropylphenylphosphine dichloride substituted-polymers are discussed with the aid of semi-empirical computer calculations. Received: 17 June 1997/Revised: 4 September 1997/Accepted: 9 September 1997     

Synthesis and exchange reactions of polymers containing reactive phthalimide groups

N-Methacryloyloxyphthalimide (NMPI) and N-methacryloyloxytetrabromophthalimide (NMTPI) were prepared by the reaction of methacrylic acid with N-hydroxy-phthalimide and N-hydroxytetrabromophthalimide, respectively. The resulting monomers were polymerized. The reactions of the resulting polymers with hydroxy and amine compounds have been studied.     

Synthesis and characterization of novel monomers and polymers containing chiral (−)-menthyl groups

To investigate the steric effects of chiral menthyl groups on the induction of cholesteric liquid crystals and the sensitivity of the photoisomerizable azobenzene derivatives, a series of chiral monomers and a photoisomerizable chiral azobenzene derivative with various spacers end-capped with (−)-menthyl group were synthesized. The structures of the novel chiral compounds synthesized in this investigation were identified using ¹³C NMR, FTIR, and elemental analysis. The phase transition temperatures of the chiral compounds were investigated using X-ray diffraction, differential scanning calorimetry, and polarizing optical microscopy. The thermogravimetric characteristics, the glass-transition temperatures (T_g) and the weight-average molecular weights (M_w) of the homopolymers were also evaluated. Polymers containing chiral menthyl groups with a biphenyl segment were found to reveal high thermal resistance. However, the existence of the steric hindered menthyl group disturbed the arrangement of chiral monomers leading to the disappearance of liquid crystal phases. The specific optical rotation of the synthesized monomers and polymers were also evaluated. The effect of the synthesized chiral compounds, monomers and photoisomerizable azobenzene derivative on the induction of the cholesteric liquid crystal films was investigated. The morphological network structure of the polymer matrix inside a liquid crystal cell was studied using a scanning electron microscope (SEM). The phototuning ability of the AzoM on the cholesteric liquid crystals was also established.     

Synthesis,characterization, and thermal behavior study of methyl methacrylate polymers containing 4‐carbazole substitutes

A new polymerizable monomer, [4‐(9‐ethyl)carbazolyl]methyl methacrylate ( 2 ), was synthesized by reacting of methacrylic acid and 4‐hydroxymethyl‐9‐ethyl carbazole ( 1 ) by esterification procedure in the presence of N,N′‐dicyclohexylcarbodiimide. The resulting monomer was then polymerized free‐radically to form the poly(methyl methacrylate) containing 4‐(9‐ethyl)carbazolyl pend ent groups. Also, copolymerization of monomer 2 with various acrylic monomers such as methyl methacrylate, ethyl methacrylate, methyl acrylate, ethyl acrylate, and n‐butyl acrylate by azobisisobutyronitrile as a free radical polymerization initiator gave the related copolymers in high yields. The structure of all the resulted compounds was characterized and confirmed by FTIR and ¹H NMR spectroscopic techniques. The average molecular weight of the obtained polymers was determined by gel permeation chromatography using tetrahydrofurane as the solvent. The thermal gravimetric analysis and differential scanning calorimeter instruments were used for studying of thermal properties of polymers. It was found that, with the incorporation of bulky 4‐(9‐ethyl)carbazolyl substitutes in side chains of methyl methacrylate polymers, thermal stability and glass transition temperature of polymers are increased. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 4989–4995, 2006     

Synthesis of potentially piezoelectric polymers containing tetracyanocyclobutyl side groups

Three new monomers containing the tetracyanocyclobutyl substituents were synthesized: p-(tetracyanocyclobutyl) styrene 1, p-(1′-methyl-2′,2′,3′,3′-tetracyanocyclobutyl)-α-methylstyrene 2 and [p-(tetracyanocyclobutyl)phenyl] acrylate 3, with the aim of obtaining potentially piezoelectric polymers which contain substituents with high dipole moments. Moderate molecular weight polymers were obtained from monomer 1 only, 2 and 3 did not polymerize. The inhibiting effect of the tetracyanocyclobutyl group was responsible for the molecular weights as demonstrated by model experiments.     

Synthesis and characterization of polymers with pendent phosphonate groups

Soluble chloromethylated polystyrene and its copolymers with vinylidene chloride as well as poly(phenyl oxides) brominated in the side chains and in the ring were synthesized and characterized in detail by NMR. The halogenated polymers were phosphonylated with alkyl phosphites. Uncrosslinked polymers with pendent phosphonate groups were prepared in the presence of etheral solvents, which solvate the ionic intermediates of the Arbuzov reaction. These polyphosphonates are highly hygroscopic and are soluble in a variety of solvents. Their T_g's are in the range of 50–175°C. Their thermal behavior was analyzed on the basis of thermogravimetric measurements combined with mass-spectrometric analysis. Poly(styrene phosphonate) seems to be the most stable, and its thermal decomposition starts at ～330°C. The polymeric phosphonates are compatible with an unusually large number of polymeric systems and seem to form “true” polymeric alloys with acetylcellulose.     

Synthesis and characterization of photoelectronic polymers containing triphenylamine moiety

Several polymers containing triphenylene moieties in main chain were synthesized by Knovenagel or Wittig condensations. The polymers were characterized by ¹H NMR, IR, GPC, TG, UV–vis, FL and CV. Results indicated that PNB, which was prepared from the polycondensation of 4,4′-dialdehyde-4″-n-butyltriphenylamine with 1,4-bis(triphenylphosphonionmethyl)benzene dibromide, is the most thermally stable one and that PNP, which was prepared from the polycondensation of 4,4′-dialdehyde-4″-n-butyltriphenylamine with p-phenylene diacetonitrile, is the most thermally instable one. The fluorescence quantum efficiency of PNB is 94.3%, which is a high value for optoelectronic polymer materials. All the polymers have a similar CV curve with a reversible oxidation peak and two reduction peaks except that PNB has a single reduction peak.     

Synthesis and thermal characterization of chemically modified cardanol polymers

Cardanol was functionalised to incorporate elements such as phosphorus and bromine and polymerised with formaldehyde or hexamethylenetetramine (HMTA) to get flame retardant polymers. Thus, monocardanyl phosphoric acid (MCPA), its bromoderivative (BrMCPA), and their formaldehyde condensates (MCPAF and BrMCPAF) and cross-linked polymers were prepared and characterized by IR, NMR, and GPC. Flammability and thermal stability of these polymers were evaluated by LOI and TGA, respectively, and compared with those of conventional cardanol-formaldehyde (CF) resin and its bromoderivative. TGA of MCPAF showed that although it is initially less stable than that of CF, its stability increases above 500°C over that of CF. Char yields of MCPAF and BrMCPAF are 21 and 27, respectively, and corresponding LOI values are 27 and 49. The present data do not support any synergism nor any additive effect between phosphorus and bromine, but a positive interaction between them is indicated with phosphorus mainly contributing in the condensed phase and bromine in the vapour phase mechanism. The activation energies in the range 20–30 kcal/mol for MCPAF suggest an ionic mechanism for its decomposition, whereas mainly a free radical type of decomposition is inferred for BrMCPAF with an activation energy in the range of 35–50 kcal/mol. © 1993 John Wiley & Sons, Inc.     

Synthesis and characterization of polyamides containing arylene sulfide-sulfone groups

Polyamides containing arylene sulfide as well as arylene sulfide-sulfone linkages were prepared from bis(4-phenylthio)dibenzoyl chloride (BPCl), 4,4′-[sulfonylbis(4-phenylthio)]dibenzoyl chloride (SPCl) and aromatic diamines both by solution and interfacial polymerization techniques. In the solution polymerization the effect of two different acid acceptors, lithium chloride and triethylamine, on inherent viscosity of the polyamides was studied. The effect of aromatic sulfone ether diamines and conventional aromatic diamines on viscosity and thermal properties of polyamides was also investigated. The polyamides prepared were characterized by IR, ¹H NMR, elemental analysis, solution viscosity, thermogravi-metry, differential scanning calorimetry and X-ray diffraction. Thermal and physical properties of polyamides prepared from BPCl and SPCl were compared.     

Synthesis and characterization of polyacrylates containing charge transfer groups

Summary Polyacrylates containing para-nitro azobenzene have been synthesized by free radical polymerization. The influence of the length of the spacer of the homopolyacrylates (HPn, n=3,4,6), content of methyl acrylate in the copolyacrylates (CP6) with para-nitro azobenzene groups on the thermal properties, such as liquid crystallinity, Tg and Tm, was studied by DSC, WAXD and polarized optical microscopy. Among the polymers studied, only the homopolyacrylate (HP6) with six carbon atoms in the spacer exhibited a nematic phase. The second-harmonic generation (SHG) signal of the poled HP6 film was detected qualitatively by Maker-fringer method.     

Synthesis and catalytic activity of optically active polymers containing oxime groups

Optically active polymers containing oxime groups have been prepared: (i) by partial quaternization of poly(4-vinyl pyridine) (P4VP) with phenacyloxime bromide and with (+)-(S)-1-bromo-2-methylbutane; and (ii) by reaction of the copolymer from 4VP and (+)-(S)-5-methyl-1-hepten-3-one with hydroxylamine. These polymers have been used as catalysts for the esterolysis of esters of p-nitrophenol with non-chiral and with chiral acids. The kinetic parameters of the catalytic process are markedly dependent on the structure of polymer and substrate. A moderate chiral discrimination of the antipodes of p-nitrophenyl 2-methylbutanoate is observed with the catalyst obtained from the copolymer of 4VP with (+)-(S)-5-methyl-1-hepten-3-one.     

Synthesis and characterization of poly(arylene ether ketone) (co)polymers containing sulfonate groups

Poly(arylene ether ketone)s containing sulfonate groups were synthesized by aromatic nucleophilic polycondensation of 4,4′-difluorobenzophenone (DFK), sodium 2,5-dihydroxybenzensulfonate (SHQ) and bisphenols. Only low-molecular weight oligomer was obtained when hydroquinone (HQ) was employed as comonomer, while copolymerization of DFK, SHQ, and phenolphthalein (PL) proceeded quantitatively to high-molecular weight (reduced viscosities above 0.68 dL/g) in dimethylsulfoxide at 175 °C in presence of anhydrous potassium carbonate. The sulfonated polymers were soluble in dipolar aprotic solvents, such as N,N-dimethylactamide and N-methyl-2-pyrrolidinone. Tough membranes cast from N,N-dimethylformamide solution with SHQ/DFK mole ratios ≤65:35 were obtained. Both glass transition temperatures and hydrophilicity of the copolymers increased with the content of sodium sulfonate groups. The materials are candidates as new polymeric electrolytes for proton exchange membranes.     

Synthesis and characterization of polymers containing naphthyl-2H-benzotriazoles, 2. Polymer synthesis and characterization

2-(2-Hydroxy-7-(meth)acryloyloxynaphthyl)-2H-benzotriazoles were polymerized and copolymerized with styrene and methyl methacrylate in dichloromethane using azoisobutyronitrile as the initiator. The polymer composition was determined by UV spectroscopy and compared with elemental analytical data; the molecular weights were determined by GPC. In homopolymerization, low molecular weight products were obtained due to the bulky naphthyl-2H-benzotriazole units. In the case of copolymerization with methyl methacrylate it was found, that the composition of the polymers was very close to the initial ratio of the monomers, whereas in copolymers with styrene the amount of incorporated benzotriazole was higher.     

Redox polymers containing p-phenylenediamine groups

Oxidation-reduction reactions and some applications of polymers containing p-phenylenediamine skeleton in side branches were studied in aqueous solutions. The polymer was used also for preparation of immobilized enzymes by oxidative coupling reaction. The materials were prepared under biologically tolerable conditions and exhibited fairly high biological activity.     

Study on organosilicon positive resist. I. Syntheses and characterization of silsesquioxane,siloxane, and silmethylene polymers with phenolic hydroxy groups

Silsesquioxane, siloxane, and silmethylene polymers with phenolic hydroxy groups were prepared in order to obtain alkali-soluble organosilicon polymers. These polymers have structures in which the phenol moieties are separated by one carbon from the silicon. The hydroxy groups were protected as methoxy groups in polymerization processes, then were changed into hydroxy groups by a reaction with trimethylsilyl iodide followed by alcoholysis. In the course of discussion on the characteristics of these polymers, silsesquioxane with phenolic hydroxy groups is found to possess excellent properties for matrix resins of alkalidevelopable organosilicon resists, such as O₂RIE resistance and heat resistance.