New oligomer‐bound antioxidants in natural rubber/polybutadiene rubber and natural rubber/styrene–butadiene rubber blends

New paraphenylene diamine antioxidants were prepared. The efficiency and permanence of these oligomer‐bound paraphenylene diamines were compared with those of conventional amine‐type antioxidants in elastomer blends such as natural rubber/styrene–butadiene rubber and natural rubber/polybutadiene rubber. These oligomer‐bound antioxidants showed improved aging resistance and ozone resistance in comparison with the blends containing conventional antioxidants. The liquid oligomer‐bound paraphenylene diamine could replace the plasticizer required for compounding. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 437–443, 2004     

Synthesis and characterization of new soluble polyamides from an unsymmetrical diamine bearing a bulky triaryl pyridine pendent group

New unsymmetrical diamine monomer containing triaryl pyridine pendent group, 2,4‐diaminophenyl [4‐(2, 6‐diphenyl‐4‐pyridyl) phenyl]ether, was synthesized via aromatic substitution reaction of 1‐chloro‐2,4‐dinitrobenzene with 4‐(2,6‐diphenyl‐4‐pyridyl) phenol, followed by Pd/C‐catalyzed hydrazine reduction. Five Polyamides (PA) were prepared by the phosphorylation polycondensation of different dicarboxylic diacids with the diamine. Inherent viscosities of PAs were in the range 0.51–0.59 g/dL indicating formation of medium molecular weight polymers. The weight and number average molecular weights of a PA, (PA‐d), determined by GPC were 6944 g/mol and 17,369 g/mol, respectively. PAs exhibited glass‐transition temperatures (T_g) in the range 140–235°C. These polymers, essentially amorphous, were soluble in polar aprotic solvents such as DMF, NMP, DMAc, DMSO, pyridine, m‐cresol, and THF. The initial decomposition temperatures (T_i) of PAs, determined by TGA in air, were in the range 300–380°C indicating their good thermal stability. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis and characterization of novel aromatic polyamides bearing CF3, quinoxaline‐anthraquinone pendants: Study of photophysical and electrochemical properties by using nanocomposite electrode paste

A new aromatic diamine, 2,3‐bis(4‐(4‐amino‐2‐(trifluoromethyl) phenoxy)phenyl)naphtho[2,3‐f]quinoxaline‐7,12‐dione, was synthesized and fully characterized by using FTIR, ¹H and ¹³C NMR, DEPT technique, and elemental analysis. A series of novel fluorescent anthraquinone‐quinoxaline containing polyamides (PAs) with inherent viscosities of 0.39–0.62 dL/g was prepared by direct polycondensation of the diamine with various dicarboxylic acids. These PAs were readily soluble in many polar aprotic organic solvents and could be solution‐cast into tough and flexible films. The PAs exhibited glass transition temperatures (T_g)s between 230 and 323°C, and 10% weight loss temperatures in the range of 362–433°C in N₂. All of the PAs have fluorescence emission in solution and in solid state with maxima around 452–510 nm and with the quantum yields in the range of 6–17%. Also, cyclic voltammetry (CV) method was used to study the electrochemical oxidation behavior of these polymers at the surface of a modified multiwalled carbon nanotube (MWCNT)s glassy electrode. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Polyamides obtained by direct polycondesation of 4‐[4‐[9‐[4‐(4‐aminophenoxy)‐3‐methyl‐phenyl] fluoren‐9‐YL]‐2‐methyl‐phenoxy]aniline with dicarboxylic acids based on a diphenyl‐silane moiety

Polyamides (PAs) containing fluorene, oxyether, and diphenyl‐silane moieties in the repeating unit were synthesized in > 85% yield by direct polycondesation between a diamine and four dicarboxylic acids. Alternatively, one PA was synthesized from an acid dichloride. The diamine 4‐[4‐[9‐[4‐(4‐aminophenoxy)‐3‐methyl‐phenyl]fluoren‐9‐yl]‐2‐methyl‐phenoxy]aniline ( 3 ) was obtained from the corresponding dinitro compound, which was synthesized by nucleophilic aromatic halogen displacement from p‐chloronitrobenzene and 9,9‐bis (4‐hydroxy‐3‐methyl‐phenyl)fluorene ( 1 ). Monomers and polymers were characterized by FTIR and ¹H, ¹³C, and ²⁹Si‐NMR spectroscopy and the results were in agreement with the proposed structures. PAs showed inherent viscosity values between 0.14 and 0.43 dL/g, indicative of low molecular weight species, probably of oligomeric nature. The glass transition temperature (T_g) values were observed in the 188–211°C range by DSC analysis. Thermal decomposition temperature (TDT_10%) values were above 400°C due to the presence of the aromatic rings in the diamine. All PAs showed good transparency in the visible region (>88% at 400 nm) due to the incorporation of the fluorene moiety. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

NMR spectroscopy as basis for characterization of Pluronic® F108 and its derivatives

The hydroxyl end groups of Pluronic®F108 {a triblock copolymer surfactant of poly(ethylene glycol) and poly(propylene glycol) [PEG‐PPG‐PEG]} were modified into primary amine, sulfonic acid, and quaternary ammonium equivalents for use in affinity chromatography. NMR was used for monitoring the efficacy of modifications on intermediaries and final products. The primary amine equivalents were prepared via conversion of the hydroxyl groups to a tosylate, its displacement with an azide, followed by reduction to the primary amine. The sulfonic acid equivalents were prepared via hydroxyl group tosylation, the displacement of tosylate with thiol, and its oxidation to sulfonic acid. The conversion to trimethyl ammonium was achieved via hydroxyl group tosylation, tosylate displacement by halide, and halide displacement with trimethylamine. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 109–117, 2000     

Soluble High-Temperature Polymers Containing a Tetraphenylthiophene Unit

Soluble high-temperature polymers containing a tetraphenylthiophene unit were successfully prepared. Four types of tetraphenylthiophene monomers—diamine, diisocyanate, dicarboxylic acid chloride, and dibromide—were synthesized starting from tetraphenylthiophene, which was readily obtained by the reaction of benzyl chloride and sulfur. Aromatic polyimides and copolyimides were prepared by the reactions of tetraphenylthiophene diamine with tetracarboxylic dianhydrides, tetraphenylthiophene diisocyanate with tetracarboxylic dianhydrides, and tetraphenylthiophene diamine with tetracarboxylic dithioanhydrides. Aromatic polyamides and copolyamides were obtained from the reaction pairs of tetraphenylthiophene diamine and dicarboxylic acid chlorides, tetraphenylthiophene dicarboxylic acid chloride and diamines, and tetraphenylthiophene dibromide, diamines, and carbon monoxide. Similarly aromatic polyamide-imides were prepared by the reaction of tetraphenylthiophene diamine with 4-chloroformylphthalic anhydride, and tetraphenylthiophene diisocyanate with trimellitic anhydride. The reaction of tetraphenylthiophene dicarboxylic dichloride with bisphenols and aminophenols afforded aromatic polyesters and polyamide-esters, respectively. Aromatic polyazomethines were prepared by the reaction of tetraphenylthiophene diamine and dialdehydes. All the polymers were obtained in high molecular weights, and all were soluble in organic solvents and had high glass transition temperatures around 300°C.     

Synthesis and characterization of new polyamides and polyimides containing dioxypyrimidine moiety in the main chain with bulky imidazole pendent group: solubility, thermal and photophysical properties

A new symmetrical diamine monomer containing dioxypyrimidine and two diaryl imidazole bulky pendent group was synthesized by the nucleophilic substitution reaction of 4,6 dihydroxy pyrimidine with the synthesized 2-(2-chloro-5-nitrophenyl)-4,5-diphenyl-1H-imidazole (I). A series of novel fluorescent imidazole-containing polyamides (PAs) with inherent viscosities of 0.52–0.78 dL/g was prepared by direct polycondensation of the diamine with various dicarboxylic acids. These PAs were readily soluble in many organic solvents and could be solution-cast into tough and flexible films. The PAs exhibited glass transition temperatures (T_g)s between 202 and 260 °C, and 10% weight loss temperatures in the range of 345–470 °C in air. In addition, three novel polyimides (PIs) with inherent viscosities of 0.38–0.56 dL/g were prepared by addition reaction of the diamine with commercially available tetracarboxylic dianhydrides and subsequent chemical imidization. The PIs exhibited good solubility in polar solvents such as NMP. These polymers exhibited T_gs in the range of 237–285 °C and their 10% weight-loss temperatures varied from 440 to 520 °C.     

Adducts of cyclic acid anhydrides and fatty amines as anti-rust additives in water-based cutting fluids

A variety ofN-alkyl carboxylic acid amides was prepared from the reaction of cyclic dicarboxylic acid anhydrides and various amines, and screened for anti-rust properties and antimicrobial activity in spent coolants of water-based cutting fluids. The triethanol amine salts of the adducts of maleic anhydride with octylamine, decylamine, dodecylamine and oleylamine, and the one of phthalic anhydride with octylamine showed both good anti-rust and antimicrobial activity.     

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     

羧酸对羧酸镧热稳定剂性能的影响

分别合成一元羧酸、二元羧酸、羟基羧酸镧热稳定剂,用刚果红法分别对其静态热稳定性进行了测试。结果表明:影响稀土镧热稳定剂性能的两个主要因素是稳定剂中稀土镧含量和有机酸碳链类型,直链二元酸镧热稳定剂的热稳定性优于直链一元酸镧和羟基羧酸镧;添加2.5%十三碳二元酸镧热稳定剂的PVC的热稳定时间达到45 min以上。     

Preparation and properties of fluorinated oligomer with tertiary amine structure in the UV curable coatings

A novel fluorinated oligomer with tertiary amine structure was synthesized by isophorone diisocyanate, 2‐hydroxyethyl acrylate, and fluorinated diol, which was prepared via Michael addition reaction between diethanolamine and dodecafluoroheptyl acrylate. The structure of fluorinated oligomer was confirmed by FTIR. The prepared fluorinated oligomer was added into the UV curable coatings, the influences of fluorinated oligomer on the cured degree and double bond conversion was analyzed by FTIR and gel content. The conversion ratio is increased when the fluorinated oligomer increased, which is due to the tertiary amine structure in the prepared product. The characteristics of UV cured films such as thermal properties, hydrophobicity, chemical resistance, mechanical properties, and hardness were characterized with the TGA, contact angle, and DMA. Results show that thermal stability, hydrophobicity, and chemical resistance are improved when fluorinated oligomer is introduced into the UV curable coatings. The DMA and hardness results indicated that the mechanical properties of UV cured films were improved and the flexibility decreased. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44387.     

Polypropylene nanocomposite using maleated PP and diamine

The insertion of the aliphatic diamine inside the organoclay will help the dispersion of the clay platelets in the PP/clay nanocomposite due to the reaction between the maleated PP and the diamine. Cloisite®20A was just simply mixed with hexamethylene diamine (HMDA) under shearing condition in Brabender mixer. HMDA group was successfully penetrated into silicate layers. As a result of penetration, d‐spacing of organoclay was increased. Polypropylene/clay nanocomposites were prepared by compounding with maleated PP and amine‐treated clay. From the FTIR spectra, reaction between amine group and maleic‐anhydride group was confirmed. The effect of the organoclay on the properties of the nanocomposite such as the morphology, dynamic mechanical properties, crystal structure and crystallization behavior, glass transition temperature, thermal stability, and tensile properties were investigated and analyzed. Nanocomposites with amine‐treated clays show enhanced properties compared with those with non–amine‐treated clay (Cloisite®20A). From the TEM analysis, nanocomposites with amine‐treated clays shows better dispersibility compared with those with Cloisite®20A alone. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Synthesis and properties of amphotropic hydrogen bonded liquid crystalline (LC) poly(ester amide)s (PEA): effect of aromatic moieties on LC behavior

Twelve hydrogen bonded aromatic-aliphatic poly(ester amide)s differing in the structures of their aromatic moieties (isophthalic, terephthalic, 2,6-naphthyl and 4,4′-biphenyl moieties of the dicarboxylic acid and phenylene and xylylene moieties of the amido diol part) were prepared by the polycondensation of amido diols with acid chlorides of isophthalic acid, terephthalic acid, 2,6-naphthalic dicarboxylic acid and 4,4′-biphenyl dicarboxylic acid, respectively. The amido diols were prepared by the aminolysis of γ-butyrolactone with hexamethylene diamine, para phenylene diamine and para xylylenene diamine, respectively. The PEAs were characterised for elemental analysis, FTIR, ¹³C NMR, TGA, DSC, POM, isothermal viscosity measurements and WAXD. Here we are presenting the effect of aromatic moieties on the thermotropic and lyotropic (amphotropic) properties of PEAs. These PEAs are essentially constituted of six types of structural entities, i.e. isophthalic, terephthalic, 2,6-naphthalic and 4,4′-biphenyl moieties containing dicarboxylic acid and the aliphatic, aromatic (phenylene and xylylene moieties) of the di-amide linkage of the amido diol part. The structure of the polymers even in the mesophase is dominated by hydrogen bond interaction between the adjacent chains and also inter plane mesogenic interaction between the rigid aromatic group. It was observed morphologically that the formation of different forms of nematic/smectic/columnar/spherullitic phases in PEAs are due to the delicate balance of self assembling through hetero intermolecular hydrogen bonded amide-amide and amide-ester net works and also inter-plane mesogenic interactions.     

Novel sorbents based on silica coated with polyethylenimine and crosslinked with poly(carboxylic acid): Preparation and characterization

Novel sorbents based on silica coated with polyethylenimine (SilPEI) and crosslinked with poly(carboxylic acid) were prepared and characterized. These sorbents are to be used for heavy metal decontamination of aqueous solutions and have to be prepared in easy and ecological ways. A part of the carboxylic moieties [from ethylenediaminetetraacetic acid (EDTA) or citric acid] reacts with some of the amine groups of polyethylenimine, initially coated onto the silica, whereas the other part remains free for further metal complexation. By changing various parameters (temperature, pH, presence or absence of an amide‐forming agent), the conditions to prepare the best sorbent—that is, the sorbent exhibiting both a high capacity for metal complexation and good stability in an acidic medium (conditions for metal desorption or stripping)—were defined. The sorbent was prepared by a reaction of 1 g of SilPEI and 1 g of EDTA in water at 0°C, pH 6, during 10 h, using 0.5 g of 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide hydrochloride as a coupling agent. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 799–805, 2003     

Influence of seed polymer molecular weight on polymerization kinetics and particle morphology of structured styrene–butadiene latexes

Heterogeneous film‐forming latexes were prepared using two‐stage, seeded emulsion polymerization. The polymerization was performed in a calorimetric reactor with a control unit that monitored the reaction rate and controlled the charging rate of the monomers. Three types of styrene seed latexes were prepared at 70°C. The first was an unmodified polystyrene (PS) latex. The second had the molecular weight lowered by the use of carbon tetrachloride (CCl₄) as a chain‐transfer agent, added at the start of the polymerization. For the third one, divinylbenzene (DVB) was used as a comonomer. DVB was added under starved conditions near the end of the polymerization to achieve crosslinked particle shells and to introduce double bonds as possible grafting sites. The second polymerization step was performed at 80°C as a batch operation in a 200‐mL calorimeter reactor. The second‐stage polymer was poly(styrene‐co‐butadiene‐co‐methacrylic acid) (S/B/MAA). A fixed S/B ratio was used together with varying small amounts of MAA. Particle morphology and particle‐size distributions were examined after the second stage using TEM after staining with osmium tetroxide. The particle morphology was found to depend on both the seed composition and the amount of MAA used in the second stage. Molecular weight and crosslinking of the DVB‐containing seed influenced the internal particle viscosity, which gave differences in the polymerization rate and the particle morphology. Crosslinking of the second‐stage polymer decreased the monomer concentration in the particles, which could be detected as a change in the slope the pressure/conversion curve. This phenomenon was used to indicate the critical conversion for crosslinking of the second‐stage polymer. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 297–311, 2000     

Silane functionalization of perfluoroether oligomers for reaction management and morphology control of two‐phase epoxy networks

Mixtures of an epoxy resin, hardener, and acid functionalized perfluoroether oligomers will readily undergo phase separation during curing. However, the conditions to bring about the growth of nuclei into microscopic particles have hitherto been found only for systems cured with anhydrides. In the present study perfluoroether oligomers were functionalized by established procedures to introduce both carboxylic acid groups and alkoxysilane groups in sites within the chain extended segments. The presence of alkoxysilane groups together with the prereaction step with an excess epoxy resin, prior to the addition of the aromatic amine hardener, induced phase separation by a nucleation‐and‐growth mechanism. The dual functionality in the perfluoroether oligomer was even more beneficial when the alkoxysilane groups were hydrolyzed prior to the addition of the amine hardener. Under such circumstances the precipitation of the perfluoroether oligomer occurred quantitatively, as indicated by the complete absence of any plasticization effects in the epoxy matrix. From electron microscopy examinations, thermal analysis, and measurements of mechanical properties it was possible to deduce a plausible mechanism for the formation of the typical core‐shell aggregates within the precipitated particles for these systems, which could also be applied to other systems, such as those using carboxylic‐acid‐terminated butadiene acrylonitrile oligomers. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1036–1049, 2005     

Separation Behavior of Composite Polyamide Membranes from Mixed Amines: Effects of Interfacial Reaction Condition and Chemical Post-Treatment

Abstract

Composite polyamide membranes are prepared using in-situ interfacial polymerization using mixed amine system comprising 1,4-phenylene diamine and pipperazine. Separation performance of the membranes are studied as a function of the concentration of amine and acid chloride, the concentration ratio of the amines, nature of the acid chloride, and the presence of surfactant and acid acceptor in the aqueous reagent. The effect of esterification and hydrazide reactions involving residual carboxylic acid groups in the polymeric membranes on the co-polymeric composite membrane performance is also studied. The membrane performance can be tailored easily by conversion of the residual reactive functional groups in post-treatment.     

Reactive blending approach to modify spin‐coated epoxy film: Part I. Synthesis and characterization of star‐shaped poly(ϵ‐caprolactone)

To effectively modify the properties of an epoxy, branched oligomers were synthesized from ?‐caprolactone (CL) and end‐functionalized to realize network precursors that can be reactively blended with the epoxy. The ring‐opening polymerization (ROP) of the CL in the presence of polyglycerol (PGL) initiator (3.9 and 9.1 mol %) and Sn(II) 2‐ethylhexanoate catalyst yielded oligomers with hydroxyl end‐groups, which were converted to carboxylic acid functionality by reaction with succinic anhydride. The functionalized oligomers had a four‐armed structure and the molecular weight of the oligomers could be controlled by the ratio of CL to PGL in the feed. To achieve an adequately crosslinked network in the reactive blending, a dual‐catalyzed reaction scheme was employed. First the oligomer was incorporated into the epoxy matrix in an imidazole‐catalyzed reaction and then the crosslinking was completed with an acid‐catalyzed ROP of the residual epoxies. Investigations showed that toughened coatings could be prepared from the inherently brittle epoxy through proper choice of the blending ratio of oligomer to epoxy. The blending increased surface hydrophobicity at high concentrations of functionalized oligomer, but did not have an adverse effect on the inherently advantageous endothelial cell spreading. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 3677–3688, 2006     

Synthesis and identification of organosoluble polyamides bearing a triaryl imidazole pendent: Thermal,photophysical, chemiluminescent,and electrochemical characterization with a modified carbon nanotube electrode

A novel monomer containing a triaryl imidazole pendent group was successfully synthesized by nucleophilic substitution of bisphenol A with 2-(2-chloro-5-nitrophenyl)-4,5-diphenyl-1H-imidazole (I). A series of new polyamides (PAs) with inherent viscosities of 0.95–1.2 dL/g was prepared by direct polycondensation of the diamine with various dicarboxylic acids. These PAs were readily soluble in many organic solvents and gave tough and flexible films by solution casting. These PAs exhibited T_gs between 189 °C and 252 °C, and 10% weight loss temperatures in excess of 400 °C with up to 68% char yield at 600 °C in air. All of the PAs emitted a greenish-yellow light in dilute THF solution, with photoluminescence (PL) quantum yields in the range of 10–25%. The chemiluminescent activity and electrochemical oxidation of the PAs were also investigated.     

Polyurethanes from soybean oil,aromatic, and cycloaliphatic diamines by nonisocyanate route

Polyurethanes were prepared via a nonisocyanate route, by reacting carbonated soybean oil (CSBO) with aromatic and cycloaliphatic diamines. Nonisocyanate polyurethanes prepared form CSBO and aliphatic diamines have relatively low tensile strength and one of the possible ways to increase strength and rigidity is to use diamines with rigid aromatic or cyclic structure. The effect of amine structure and amine to carbonate ratio on polyurethane structure and mechanical, physical, and swelling properties was studied. m‐xylylene diamine (m‐XDA), p‐xylylene diamine (p‐XDA), and isophorone diamine were used as the reactants, with amine to carbonate ratios of 0.5 : 1, 1 : 1, and 1 : 2. All amines produced elastomeric polyurethanes with glass transitions between ?6° C and 26°C, as measured by differential scanning calorimeter (DSC). T_g was primarily controlled by the amine‐to‐cyclic carbonate ratio, and to a lesser extent by the amine structure. The highest tensile strength was obtained for p‐XDA and the lowest for m‐XDA as a result of differences in hydrogen bonding. Tensile strength and hardness were higher than in aliphatic diamine‐based polyurethanes. Swelling in toluene and water depended on the polarity of polyurethane networks that was dominantly controlled by the amine‐to‐cyclic carbonate ratio. Swelling in toluene was higher at the lower amine to carbonate ratio due to lower polarity of the polyurethane matrix. Swelling in water behaved quite the opposite, the degree of swelling for the more polar polyurethane matrix was higher. Reaction temperatures of 70–100°C were high enough to promote ester group cleavage and along with urethanes, amide formation was always present. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013