Synthesis and characterization of poly[(1‐vinyl‐1,2,4‐triazole)‐co‐(monomer with carboxylic acid group(s))] and determination of monomer reactivity ratios: I. Acrylic acid

Copolymers of 1‐vinyl‐1,2,4‐triazole (VTAz) and acrylic acid (AA) having different mole ratios were synthesized using free radical‐initiated solution polymerization in dimethylformamide at 70 °C with α,α′‐azobisisobutyronitrile as initiator in nitrogen atmosphere. The compositions of the synthesized copolymers for a wide range of monomer feeds were determined using Fourier transform infrared (FTIR) spectroscopy through recorded absorption bands for VTAz (1510 cm^?1, C?N (triazole ring) stretching mode) and AA (1710 cm^?1, C?O stretching mode) units. The structures of the copolymers were characterized using FTIR and ¹H NMR spectroscopy. The copolymer compositions were also determined from ¹H NMR analysis following proton signals of carboxyl group at 11.8–12.5 ppm of AA and of triazole ring at 7.5–8.1 ppm of VTAz. Monomer reactivity ratios for the VTAz‐AA pair were estimated using linear methods, i.e. Fineman–Ross (FR) and Kelen–Tüdös (KT). From FTIR evaluation, monomer reactivity ratios were calculated as r₁ = 0.404 and r₂ = 1.496 using the FR method and r₁ = 0.418 and r₂ = 1.559 using the KT method. These values were found to be very close to those obtained from NMR evaluation. The two cases r₁r₂ < 1 and r₁ < r₂ indicated the random distribution of the monomers in the final copolymers and the presence of a greater amount of AA units in the copolymer than in the feed, respectively. The observed relatively high activity of complexed growing radical‐AA^? … VTAz was explained by the effect of complex formation between carbonyl groups and triazole fragments in chain growth reactions. Thermal behaviours of copolymers with various compositions were investigated using thermogravimetric and differential scanning calorimetric analyses. It was observed that thermal stabilities and glass transition temperatures of the copolymers increased resulting from complex formation between acid and triazole units. © 2012 Society of Chemical Industry     

Synergistic effect of alkyl lactate functional groups on properties of methacrylate polymers

In this work, four novel different alkyl lactate methacrylate monomers were synthesized through azeotropic esterification method by reacting methyl, ethyl, propyl and butyl lactates with methacrylic acid. The prepared monomers were polymerized through solution polymerization technique and both monomers and polymers were analyzed by FTIR, ¹H NMR and ¹³C NMR spectroscopy techniques to elucidate the structure and to confirm their formation. Increasing the number of methylene units in alkyl lactate side chain decreases the glass transition temperature (T_g) of the polymers. Average molecular interchain spacing (〈R〉) of polymers was obtained from the wide-angle X-ray diffraction measurement and the values ranged from 6.26 to 7.18 Å based on the length of alkyl lactate group. The prepared polymers showed hygroscopic property and their moisture absorption was in the range of 10–24% (w/w) depending upon the length of alkyl lactate moiety, relative humidity and time. These polymers have the potential for hydrogel applications owing to their increased moisture absorption capacity. Both polymethyl and propyl lactate methacrylate showed two distinct and prominent thermal degradations whereas polyethyl and butyl lactate methacrylates showed only a single distinct and prominent thermal degradation step. An interesting result of as-synthesized polymers showed odd–even chain length effect in the properties of 〈R〉, moisture uptake and thermal stability.

     

Synthesis of branched benzoxazine monomers with high molecular mass,wide processing window,and properties of corresponding polybenzoxazines

Four cyclotriphosphazene‐based benzoxazine monomers (I, II, III, and IV) with relatively high molecular weight were synthesized by a nucleophilic substitution reaction, and their chemical structures were confirmed by ¹H‐NMR and ³¹P‐NMR. A new term, oxazine value (OV, similar to epoxy value), was first proposed to explain the structure–property relationship of the cured polymers. The polymerization behaviors of the four monomers were studied by differential scanning calorimetry and Fourier transform infrared spectroscopy. The maximum exothermic peaks of the four monomers are in the range 244–248 °C. All monomers possess a wide processing window despite their high molecular weight. The thermal stability, glass‐transition temperature (T_g), and mechanical properties of each cured polymer were studied by thermogravimetric analysis and dynamic mechanical thermal analysis. The char yield at 850 °C, T_g, and storage moduli of PIV (polybenzoxazine obtained from monomer IV) are 60.0%, 218 °C, and 9.0 GPa, respectively. The surface property and humidity absorption character of the cured polybenzoxazines were also studied. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44453.     

Preparation and characterization of the copolymer containing N‐pyridyl bi(methacryl)imide unit

The copolymer of methacrylic acid anhydride and N‐2‐pyridyl bi(methacryl)imide was prepared based on the reaction of polymethacrylic acid with 2‐pyridylamine. The molecular structure was characterized by ¹H‐NMR, FTIR, UV–Vis, and circular dichroism techniques. The physical properties of polymethacrylic acid change significantly after an introduction of 6 mol % N‐2‐pyridyl bi(methacryl)imide unit. In particular, the thermal degradation of the polymer was systematically studied in flowing nitrogen and air from room temperature to 800°C by thermogravimetry at a constant heating rate of 10°C/min. In both atmospheres, a four‐stage degradation process of the copolymer of methacrylic acid anhydride and N‐2‐pyridyl bi(methacryl)imide was revealed. The initial thermal degradation temperature T_d, and the first, second, and third temperatures at the maximum weight‐loss rate T_dm1, T_dm2, and T_dm3 all decrease with decreasing sample size or changing testing atmosphere from nitrogen to air, but the fourth temperature at the maximum weight‐loss rate T_dm4 increases. The maximum weight‐loss rate, char yield at elevated temperature, four‐stage decomposition process, and three kinetic parameters of the thermal degradation were discussed in detail. It is suggested that the copolymer of methacrylic acid anhydride and N‐2‐pyridyl bi(methacryl)imide exhibits low thermal stability and multistage degradation characteristics. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1673–1678, 2002     

Copolymerization of N‐aryl substituted itaconimide with methyl methacrylate: Effect of substituents on monomer reactivity ratio and thermal behavior

The article describes the synthesis and characterization of N‐(4‐methoxy‐3‐chlorophenyl) itaconimide (MCPI) and N‐(2‐methoxy‐5‐chlorophenyl) itaconimide (OMCPI) obtained by reacting itaconic anhydride with 4‐methoxy‐3‐chloroanisidine and 2‐methoxy‐5‐chloroanisidine, respectively. Structural and thermal characterization of MCPI and OMCPI monomers was done by using ¹H NMR, FTIR, and differential scanning calorimetry (DSC). Copolymerization of MCPI or OMCPI with methyl methacrylate (MMA) in solution was carried out at 60°C using AIBN as an initiator and THF as solvent. Feed compositions having varying mole fractions of MCPI and OMCPI ranging from 0.1 to 0.5 were taken to prepare copolymers. Copolymerizations were terminated at low percentage conversion. Structural characterization of copolymers was done by FTIR, ¹H NMR, and elemental analysis and percent nitrogen content was used to calculate the copolymer composition. The monomer reactivity ratios for MMA–MCPI copolymers were found to be r₁ (MMA) = 0.32 ± 0.03 and r₂ (MCPI) = 1.54 ± 0.05 and that for MMA–OMCPI copolymers were r₁ (MMA) = 0.15 ± 0.02 and r₂ (OMCPI) = 1.23 ± 0.18. The intrinsic viscosity [η] of the copolymers decreased with increasing mole fraction of MCPI/or OMCPI. The glass transition temperature as determined from DSC scans was found to increase with increasing amounts of OMPCI in copolymers. A significant improvement in the char yield as determined by thermogravimetry was observed upon copolymerization. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2391–2398, 2006     

Synthesis and characterization of chiral smectic side‐chain liquid crystalline polysiloxanes and ionomers containing sulfonic acid groups

The synthesis of new chiral smectic A (S_A) side‐chain liquid crystalline polysiloxanes (LCPs) and ionomers (LCIs) containing 4‐allyloxy‐benzoyl‐4‐(S‐2‐ethylhexanoyl) p‐benzenediol bisate (ABB) as mesogenic units and 4‐[[4‐(2‐propenyloxy)phenyl]azo]benzenesulfonic acid (AABS) as nonmesogenic units is presented. The chemical structures of the monomers and polymers are confirmed by FTIR spectroscopy or ¹H–NMR. Differential scanning calorimetry (DSC), optical polarizing microscopy, and X‐ray diffraction measurements reveal that all the polymers P_I–P_IV and ionomers P_V–P_VI exhibit S_A texture. The results seem to demonstrate that the tendency toward the S_A‐phase region increases with increasing sulfonic acid concentration, and the thermal stability of the S_A phase is determined by the flexibility of the polymer backbones and the interactions of sulfonic acid groups. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2335–2340, 2001     

Preparation and properties of flame retardant poly(urethane‐imide)s containing phosphine oxide moiety

The preparation of new poly(urethane‐imide)s (PUIs) having acceptable thermal stability and higher flame resistance was aimed. Two new aromatic diisocyanate‐containing methyldiphenylphosphine oxide and triphenylphosphine oxide moieties were synthesized via Curtius rearrangement in situ and polymerized by various prepared diols. Four aliphatic hydroxy terminated aromatic based diols were synthesized by the reaction between ethylene carbonate and various diphenolic substances. Chemical structures of monomers and polymers were characterized by FTIR, ¹H NMR, ¹³C NMR, and ³¹P NMR spectroscopy. Thermal stabilities and decomposition behaviors of the PUIs were tested by DSC and TGA. Thermal measurements indicate that the polymers have high thermal stability and produce high char. Polymers exhibit quite high fire resistance, evaluated by fire test UL‐94. The films of the polymers were prepared by casting the solution. Inherent viscosities, solubilities, and water absorbtion behaviors of the polymers were reported in. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

13C‐NMR, 1H‐NMR,and FT‐Raman study of radiation‐induced modifications in radiation dosimetry polymer gels

¹H‐ and ¹³C‐NMR spectroscopy and FT‐Raman spectroscopy are used to investigate the properties of a polymer gel dosimeter post‐irradiation. The polymer gel (PAG) is composed of acrylamide, N,N′‐methylene‐bisacrylamide, gelatin, and water. The formation of a polyacrylamide network within the gelatin matrix follows a dose dependence nonlinearly correlated to the disappearance of the double bonds from the dissolved monomers within the absorbed dose range of 0–50 Gy. The signal from the gelatin remains constant with irradiation. We show that the NMR spin–spin relaxation times (T₂) of PAGs irradiated to up to 50 Gy measured in a NMR spectrometer and a clinical magnetic resonance imaging scanner can be modeled using the spectroscopic intensity of the growing polymer network. More specifically, we show that the nonlinear T₂ dependence against dose can be understood in terms of the fraction of protons in three different proton pools. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1572–1581, 2001     

Studies of phosphonate‐containing bismaleimide resins. I. Synthesis and characteristics of model compounds and polyaspartimides

Two phosphonate‐containing bismaleimide (BMI) [(4,4′‐bismaleimidophenyl)phosphonate] monomers with different melting temperatures and similar curing temperatures were synthesized by reacting N‐hydroxyphenylmaleimide with two kinds of dichloride‐terminated phosphonic monomers. The BMI monomers synthesized were identified with ¹H‐, ¹³C‐, and ³¹P‐nuclear magnetic resonance (NMR) spectroscopy and elemental analysis. The phosphonate‐containing BMI monomers react with a free‐radical initiator to prepare phosphonate‐containing BMI polymers and also with various aromatic diamines to prepare a series of polyaspartimides as reactive flame retardants. The polymerization degrees of polyaspartimides depend on the alkalinity and nucleophility of diamines as chain extenders. Differential scanning calorimetry (DSC) and thermogravimetry analysis (TGA) were used to study the thermal properties of the phosphonate‐containing BMI resins such as the melting temperature, curing temperature, glass transition temperature (T_g), and thermal resistance. All the phosphonate‐containing BMI resins, except the BMI polymers, have a T_g in the range of 210–256°C and show 5% weight loss temperatures (T_5%) of 329–434 and 310–388°C in air and nitrogen atmospheres, respectively. The higher heat resistance of cured BMI resin relative to the BMI polymer is due to its higher crosslinking density. Since the recrosslinking reactions of BMI polymers and polyaspartimides occur more easily in an oxidation environment, their thermal stabilities in air are higher than are those in nitrogen gas. In addition, the thermal decomposition properties of polyaspartimides depend on the structures and compositions of both the diamine segments and the BMI segments. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1919–1933, 2002     

Synthesis and characterization of copolymers of bromoacrylated methyl oleate

In this study, methyl oleate was bromoacrylated in the presence of N‐bromosuccinimide and acrylic acid in one step. Homopolymers and copolymers of bromoacrylated methyl oleate (BAMO) were synthesized by free radical bulk polymerization and photopolymerization techniques. Azobisisobutyronitrile (AIBN) and 2,2‐dimethoxy‐2‐phenyl‐acetophenone were used as initiators. The new monomer BAMO was characterized by FTIR, GC‐MS, ¹H, and ¹³C‐NMR spectroscopy. Styrene (STY), methylmethacrylate (MMA), and vinyl acetate (VA) were used for copolymerization. The polymers synthesized were characterized by FTIR, ¹H‐NMR, ¹³C‐NMR, and differential scanning calorimetry (DSC). Molecular weight and polydispersities of the copolymers were determined by GPC analysis. Ten different feed ratios of the monomers STY and BAMO were used for the calculation of reactivity ratios. The reactivity ratios were determined by the Fineman–Ross and Kelen–Tudos methods using ¹H‐NMR spectroscopic data. The reactivity ratios were found to be r_sty = 0.891 (Fineman–Ross method), 0.859 (Kelen–Tudos method); r_bamo = 0.671 (Fineman–Ross method), 0.524 (Kelen–Tudos method). © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 2475–2488, 2004     

Sequencing of N‐vinyl‐2‐pyrrolidone/glycidyl methacrylate copolymers by one‐dimensional and two‐dimensional nuclear magnetic resonance spectroscopy

Copolymers of N‐vinyl‐2‐pyrrolidone (V) and glycidyl methacrylate (G) monomers of different compositions were prepared by free‐radical solution polymerization. The copolymer composition of these copolymers was determined with ¹H‐NMR spectra. The reactivity ratios calculated from the Kelen–Tudos and nonlinear least‐square error‐in‐variable methods were r_V = 0.03 ± 0.01 and r_G = 5.05 ± 0.84 and r_V = 0.02 and r_G = 4.72, respectively. The triad sequence distribution in terms of V and G centered triads was determined from ¹³C{¹H}‐NMR spectroscopy. The complete spectral assignment of ¹³C{¹H}‐ and ¹H‐NMR spectra was performed with the help of distortionless enhancement by polarization transfer and two‐dimensional ¹³C–¹H heteronuclear single quantum coherence. The ¹H–¹H couplings were explained with total correlation spectroscopy and nuclear Overhauser enhancement spectroscopy spectra. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 50–60, 2002; DOI 10.1002/app.10186     

Properties of hybrid materials derived from hydroxy‐containing linear polyester and silica through sol–gel process. I. Effect of thermal treatment

The transparent hybrid material, HLP/SiO₂, was prepared by an in situ sol–gel process of tetraethoxysilane (TEOS) at 30°C in the presence of hydroxy‐containing linear polyester (HLP) obtained by ring‐opening reaction of diglycidyl ether of bisphenol A (DGEBA) with adipic acid under the catalyzation of triphenylphosphine (TPP). The hetero‐associated hydrogen bonds between the HLP and the residual silanol of silica in the hybrids were investigated by FTIR spectroscopy. Upon heating the hybrid, the interfacial force between the HLP matrix and the silica network changed from hydrogen bonds into covalent Si—O—C bonds through dehydration of hydroxy groups in HLP with residual silanol groups in the silica network. The existence of covalent Si—O—C bonds was proved by solid‐state ²⁹Si‐NMR spectra. Other properties such as tensile strength, glass transition temperature (T_g ), solubility, and thermal stability of the hybrids before and after heat treatment were studied in detail. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 1179–1190, 2000     

Methacrylate/acrylate terminated derivatives of diglycidyl hexahydrophthalate: Synthesis,structural, and thermal characterization

Mono‐ or di(meth)acrylate‐terminated derivatives of diglycidyl hexahydrophthalate (ER) were prepared by reacting 1 : 1 or 1 : 2M ratio of ER and methacrylic acid or acrylic acid. These vinyl ester (VE) resins were characterized by determining epoxy equivalent weight, acid number, and molecular weight by gel permeation chromatography. Structural characterization was done by FTIR and ¹H NMR spectroscopy. In the ¹H NMR spectra of acrylate‐terminated VE resins, three proton resonance signals were observed in the region 5.8–6.4 ppm due to vinyl group while in methacrylate‐terminated VE resins only two proton resonance signals due to vinylidene protons were observed at 5.6–6.1 ppm. The Brookfield viscosity (room temperature (25 ± 2)°C) of these resins diluted with varying amounts of MMA was determined at 20 rpm. Curing behavior was monitored by determination of gel time and differential scanning calorimetry. An exothermic transition was observed in the DSC scans in the temperature range of (81–150)°C. Isothermal curing of MMA‐diluted VE resins containing AIBN as an initiator was done at 60°C for 2 h in N₂ atmosphere, and then heating for another 2 h in static air atmosphere. Thermal stability of isothermally cured resins in N₂ atmosphere was evaluated by thermogravimetric analysis. All cured resins decomposed above 310°C in single step. Thermal stability of the cured resins having acrylate end caps was marginally higher than the resins having methacrylate end groups. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Synthesis and phase separation of poly(N‐isopropyl acrylamide‐co‐methoxy polyethyleneglycol monomethacrylate)

The poly(N‐isopropyl acrylamide‐co‐methoxy polyethyleneglycol monomethacrylate, NIPAM‐co‐MPEG) with different length of ethylene oxide (EO) were synthesized from their monomers, NIPAM and MPEGs. The numbers of repeating units of EO were 6, 10, 24, and 46. The chemical structure and mole ratio of the monomers was determined by Fourier transform infrared (FTIR), ¹H‐NMR, and ¹³C‐NMR spectroscopy. The d‐spacing increased with the number of EO and the values of the copolymers were in the range of 0.437–0.452 nm. The lower critical solution temperature of the poly(NIPAM‐co‐MPEG) shifted to higher temperature as the number of EO and the amount of MPEG increased. The change of chemical shift for methoxy proton in MPEG exhibited a larger than those of the other protons of the poly(NIPAM‐co10?2MPEG). Activation energy (E_a) for methoxy proton in MPEG showed a larger value than that of the methyl proton in NIPAM. These NMR results indicate the fact that more significant conformational transformations occur in the methoxy group through the phase separation than in the methyl group in NIPAM. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 1833–1841, 2006     

Surlyn®/silicate hybrid materials. I. Polymer in situ sol–gel process and structure characterization

We report the creation of a new organic/inorganic hybrid material that results from sol–gel reactions for tetraethylorthosilicate (TEOS) within poly[ethylene‐co‐methacrylic acid], as well as within a Zn⁺² partially neutralized form of this copolymer (Surlyn®). FTIR and ²⁹Si solid‐state NMR spectroscopic probes yield information regarding molecular connectivity within the in situ grown silicate structures. FTIR analyses of Surlyn® matrix bands suggest that strong molecular level interactions between the organic and inorganic phases are not present, although there is other evidence that these phases are mechanically coupled on a larger dimensional scale. The ²⁹Si solid‐state NMR analyses indicate mainly Q₃ and Q₄ coordination states about the SiO₄ substructures, regardless of silicate content, which is in general agreement with the interpretation of the FTIR results that show incomplete condensation. Environmental scanning electron microscopy and energy dispersive X‐ray analysis results reinforce the conclusion that a significant silicate component is incorporated deep within TEOS‐treated films. Differential scanning calorimetry studies of Surlyn®‐Zn⁺²/silicate hybrids suggest that silicate incorporation essentially does not disrupt crystallinity. Thermogravimetric analyses show practically no change in the degradation onset temperature, which is consistent with organic/inorganic phase separation. The general conclusion is that a silicate phase can indeed be incorporated within this acid copolymer, as well as its Zn⁺² ionomeric form, via in situ sol–gel processes. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2832–2844, 2000     

Synthesis and characterization of aromatic/cycloaliphatic poly(amide‐ imide‐imide)s from bis(4‐amino‐ 3,5‐dimethylphenyl) cycloalkane derivatives

A series of novel aromatic diamines containing cycloaliphatic moieties was synthesized by the reaction of cycloalkanones like cyclohexanone and cycloheptanone with 2,6‐dimethylaniline. The tetrimide diacid was synthesized using the prepared diamine with 3,3′,4,4′‐benzophenonetetracarboxylic acid dianhydride/pyromellitic dianhydride and p‐aminobenzoic acid. The polymers were prepared by treating the tetrimide diacid with different aromatic diamines. The structures of the monomers and polymers were identified using elemental analysis and Fourier transform infrared, ¹H NMR and ¹³C NMR spectroscopy. The polymers show excellent solubility. The polymers are amorphous and have high optical transparency. They also show good thermal stability and their T_g value is found to be in the range 268–305 °C. Copyright © 2007 Society of Chemical Industry     

Novel regenerable N‐halamine polymeric biocides. I. Synthesis,characterization, and antibacterial activity of hydantoin‐containing polymers

Two novel cyclic‐amine monomers, i.e., 3‐allyl‐5,5‐dimethylhydantoin (ADMH) and 7,8‐benzo‐3 allyl‐1,3‐diazasprio[4.5]decane‐2,4‐dione (BADDD) were synthesized with good yields by reacting allyl bromide with 5,5‐dimethylhydantoin (DMH) and 7,8‐benzo‐1,3‐diazasprio[4.5]decane‐2,4‐dione (BDDD), respectively. The synthesized monomers were characterized by FTIR and ¹H‐NMR spectra, and copolymerized with acrylonitrile (AN), vinyl acetate (VAC), and methyl methacrylate (MMA) in a small monomer ratio of ADMH and BDDD, respectively. The copolymers were characterized by FTIR, ¹H‐NMR, and DSC studies. The N‐halamine derivatives of the corresponding copolymers were found to exhibit high antibacterial activities against Escherichia coli, and the antibacterial properties were durable and regenerable. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2460–2467, 2001     

Synthesis,thermal polymerization,and properties of benzoxazine resins containing fluorenyl moiety

Three difunctional fluorene‐based benzoxazine compounds were synthesized via Mannich condensation and were characterized by proton nuclear magnetic resonance spectroscopy (¹H NMR), Fourier transform infrared spectroscopy (FTIR), and elementary analysis (EA). The polymerization of benzoxazine monomers were investigated with differential scanning calorimeter (DSC) method. Thermal properties of the polybenzoxazines were studied by thermogravimetric analysis (TGA) and DSC. Water absorption of the polybenzoxazines was tested. Contact angle measurement was employed to characterize the surface property of materials. The glass transition temperatures (T_gs) and thermal stability were improved significantly in comparison with bisphenol‐A‐based analogue because of the incorporation of rigid fluorenyl group. The fluorenyl‐based polybenzoxazines showed hydrophobic characteristics, which was ascribed to the low polarity of fluorenyl and pi–pi stacking interaction of fluorenyl on the surface. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers     

One‐step synthesis of star‐block copolymers via simultaneous free radical polymerization of styrene and ring opening polymerization of ε‐caprolacton using tetrafunctional iniferter

Star‐block copolymers comprised of poly(styrene) (S) core and four poly(ε‐caprolacton) (ε‐CL) arms were synthesized by the combination of free radical polymerization (FRP) of S and ring opening polymerization (ROP) of ε‐CL in one‐step in the presence of tetrafunctional ineferter. The block copolymers were characterized by ¹H‐NMR and FTIR spectroscopy, gel permeation chromatography (GPC), and fractional precipitation method. ¹H ‐NMR and FTIR spectroscopy and GPC studies of the obtained polymers indicate that star‐block copolymers easily formed as result of combination FRP and ROP in one‐step. The γ values (solvent/precipitant volume ratio) were observed between 1.04–2.72 (mL/mL) from fractional measurements. The results show that when the initial S feed increased, the molecular weights of the star‐block copolymers also increased and the polydispersities of the polymers decreased. M_w/M_n values of the products were measured between 1.4 and 2.86 from GPC. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis and characterization of new cardo poly(bisbenzothiazole)s from 1,1‐bis(4‐amino‐3‐mercaptophenyl)‐4‐tert‐butylcyclohexane dihydrochloride

A new monomer 1,1‐bis(4‐amino‐3‐mercaptophenyl)‐4‐tert‐butylcyclohexane dihydrochloride, bearing the bulky pendant 4‐tert‐butylcyclohexylidene group, was synthesized from 4‐tert‐butylcyclohexanone in three steps. Its chemical structure was characterized by ¹H NMR, ¹³C NMR, MS, FTIR, and EA. Aromatic poly(bisbenzothiazole)s (PBTs V) were prepared from the new monomer and five aromatic dicarboxylic acids by direct polycondensation. The inherent viscosities were in the range of 0.63–2.17 dL/g. These polymers exhibited good solubility and thermal stability. Most of the prepared PBTs V were soluble in various polar solvents. Thermogravimetric analysis showed the decomposition temperatures at 10% weight loss that were in the range of 495–534°C in nitrogen. All the PBTs V, characterized by X‐ray diffraction, were amorphous. The UV absorption spectra of PBTs V showed a range of λ_max from 334 to 394 nm. All the PBTs V prepared had evident fluorescence emission peaks, ranging from 423 to 475 nm with different intensity. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 2000–2008, 2006