Copolymerization of glycidol with functionalized phenyl glycidyl ethers

Various copolymers of glycidol with phenyl‐containing comonomers (glycidyl 2‐methylphenyl ether, 2‐biphenylyl glycidyl ether, 4‐tert‐butylphenyl glycidyl ether, methoxyphenyl glycidyl ether, and p‐nitrophenyl glycidyl ether) were synthesized by cationic ring‐opening polymerization, for possible use as nanoparticle coatings. The copolymerization involving p‐nitrophenyl glycidyl ether produced p‐nitrophenol as a byproduct. The copolymers were found to have relatively low average molecular weights and high polydispersities, with glass‐transition temperatures in the ?20 to +10°C range (approximately). © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 1462–1466, 2005     

Properties of poly(alkylene oxide) elastomers

The catalyst comprised of triisobutylaluminum, zinc acetylacetonate, and water was used to prepare homopolymer of epichlorohydrin; copolymers of epichlorohydrin with propylene oxide, ethylene oxide, and allyl glycidyl ether; and terpolymers of epichlorohydrin, propylene oxide, and allyl glycidyl ether and of epichlorohydrin, ethylene oxide, and allyl glycidyl ether. The vulcanizates of these rubbers provide variations of stressstrain and dynamic properties, freeze point, hardness, and solvent resistance depending on the type and amount of comonomer. In general, these rubbers have excellent heat, ozone, and oxidation resistance as well as oil and solvent resistance.     

Copolymerizations of carbon dioxide and epoxides in the presence of rare earth coordinate catalyst

Carbon dioxide (CO₂) as a direct material was copolymerized with epoxides to synthesize new aliphatic polycarbonates, and the copolymerization was catalyzed by the coordinate catalyst composed of rare earth yttrium phosphonate and triisobutylaluminum [Y(P₂₀₄)₃–A1(i‐Bu)₃]. The epoxides used in this research included epichlorohydrin (ECH) and some new glycidol ether (GE) monomers prepared by the reaction of ECH and phenol or alcohol, such as α‐allyl glycidol ether, β‐chloroethyl glycidol ether, benzene glycidol ether, m‐tolyl glycidol ether, and benzyl glycidol ether. The copolymers were characterized by infrared (IR), ¹H nuclear magnetic resonance (‐NMR), and dynamic mechanical analysis. The results show that Y(P₂₀₄)₃–A1(i‐Bu)₃ had better catalytic activity in the copolymerization of CO₂ with epoxide, and the copolymerization rate of aryl GE was distinctly higher than that of aliphatic GE. Dynamic mechanical analysis indicated the glass transition temperature T_g of the copolymers GE–CO₂ were lower than that of ECH–CO₂. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 87: 2356–2359, 2003     

On the structure of trioxane copolymers with some glycidylethers

The changes of the polyoxymethylene (POM) structure by introducing comonomer units possessing side substituents (R) to the —O—CH₂—CH(R) units were studied. Various glycidyl ethers such as butyl (BGE), isooctyl (iOGE), and phenyl (PhGE) were used as comonomers with side groups of different size, volume, and steric hindrance. The influence of the quantity of the incorporated glycidyl ether (GE) comonomer units along the POM chain as well as both the type and size of the side substituent were investigated. The changes of crystallinity, melting temperature, heating and defect enthalpy, and the volume (ų) of the crystal lattice were calculated. Both the structure changes and thermal behavior were confirmed using differential scanning calorimetry (DSC) and wide-angle X-ray scattering (WAXS). Transmission electron microscopy (TEM), diffraction (TEMD) as well as scanning electron microscopy were used to investigate both structure and morphology. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2813–2823, 1999     

Synthesis and characterization of graft copolymers of hydroxypropyl cellulose with acrylamide and some comonomers

To obtain new polymeric materials for environmental management, we used pine needles from the huge forest of the Western Himalayas as a source of cellulose. Cellulose was derivatized to hydroxypropyl cellulose (HPC), a useful water‐soluble cellulose ether. HPC was graft‐copolymerized with acrylamide (AAm) with benzoyl peroxide as the initiator. At optimum grafting conditions, five different concentrations of the comonomers glycidyl methacrylate, acrylic acid, 2‐hydroxyethyl methacrylate, and acrylonitrile were grafted with AAm. Networks of HPC and AAm were also synthesized by crosslinking reactions with glutaraldehyde as a crosslinker over a range of four different concentrations of crosslinker under acidic conditions. Crosslinked networks of HPC with AAm and a comonomer at one comonomer concentration were also synthesized. Graft copolymers were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, and swelling behavior. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 545–555, 2004     

Effects of shearing and comonomer content on the crystallization behavior of poly(butylene succinate‐co‐butylene 2‐ethyl‐2‐methyl succinate)

Poly(butylene succinate‐co‐butylene 2‐ethyl‐2‐methyl succinate) (PBSEMS) random copolymers were prepared with different comonomer compositions. The effects of shearing and comonomer content on the crystallization behavior of these copolymers were investigated at 80 °C. The thermal and morphological properties of the resulting samples were also discussed. The copolymers showed a longer induction time and a slower crystallization rate with increasing comonomer content. The promoting effect of shear on the overall crystallization behavior was more notable for those copolymers containing more 2‐ethyl‐2‐methyl succinic acid (EMSA) units. The melting temperature of ‘as‐prepared’ poly(butylene succinate) (PBS) was ca. 115 °C, while that of the copolymers varied from 112 to 102 °C. Higher comonomer contents in the copolymers gave rise to lower melting temperatures and broader melting peaks. In addition, the isothermally crystallized samples showed multiple melting endothermic behavior, the extent of which depended on the comonomer content. The copolymers showed different wide‐angle X‐ray diffraction (WAXD) patterns from that of neat PBS, depending on the comonomer content and shear applied during crystallization. With increasing comonomer content, the copolymers crystallized without shearing, showing the shifting of a diffraction peak to a higher angle, while those crystallized under shear did not show any peak shift. Copyright © 2004 Society of Chemical Industry     

Copolymerization of N‐substituted maleimide with alkyl acrylate and its industrial applications

A series of new copolymers with desired thermal stability and mechanical properties for applications in leather industry were synthesized from various substituted maleimides and alkyl acrylates. Polymerization was carried out by a free‐radical polymerization using benzoyl peroxide (BPO) as initiator. The monomers and polymers synthesized were characterized by elemental analysis, IR, and nuclear magnetic resonance (NMR). Interestingly, these polymers were soluble in common organic solvents. Copolymer composition and reactivity ratios were determined by ¹H‐NMR spectra. The molecular weights of the polymers were determined by gel permeation chromatography. The homo‐ and copolymer of maleimide showed single‐stage decomposition (ranging from 300–580°C). The initial decomposition temperatures of poly[N‐(phenyl)maleimide] [poly(PM)], poly[N‐4‐(methylphenyl)maleimide] [poly(MPM)] and poly[N‐3‐(chlorophenyl)maleimide] [poly(CPM)] were higher compared to those of the copolymers. Heat‐resistant adhesives such as blends of epoxy resin with phenyl‐substituted maleimide‐co‐glycidyl methacrylate copolymers with improved adhesion property were developed. Different adhesive formulations of these copolymaleimides were prepared by curing with diethanolamine at two different temperatures (30°C and 60°C). © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1870–1879, 2001     

Biotransformation of glycidol by the unspecific wax ester synthase/acyl‐CoA:diacylglycerol acyltransferase of Acinetobacter baylyi ADP1

Glycidol was biologically derivatized by the unspecific wax ester synthase/acyl coenzyme A (acyl‐CoA): diacylglycerol acyltransferase (WS/DGAT) from Acinetobacter baylyi ADP1 into glycidyl acyl ester. Catalysis of in vitro conversion of glycidol to glycidyl acyl ester by the WS/DGAT from A. baylyi was verified by (i) a radiometric assay, (ii) thin‐layer chromatography and (iii) also by ESI‐MS. A specific activity of 50 nmol·mg^–1·min^–1 was obtained when 10 mM glycidol and 5 µM palmitoyl‐CoA were used. In vivo synthesized glycidyl acyl esters in recombinant E. coli were detected and quantified by staining with the epoxide‐specific reagent 4‐(4‐nitrobenzyl)‐pyridine. Of glycidyl acyl esters, 1.5 mg/L was obtained from the culture in the presence of 10 mM glycidol and 10 mM oleate.     

Melting behavior and crystallization kinetics of poly(butylene terephthalate‐co‐diethylene terephthalate) and poly(butylene terephthalate‐co‐triethylene terephthalate) copolyesters

The melting behavior of poly(butylene terephthalate‐co‐diethylene terephthalate) and poly(butylene terephthalate‐co‐triethylene terephthalate) copolymers was investigated by differential scanning calorimetry after isothermal crystallization from the melt. Multiple endotherms were found for all the samples, and attributed to the melting and recrystallization processes. By applying the Hoffman‐Weeks' method, the equilibrium melting temperatures of the copolymers under investigation were obtained. Two distinct peaks in the crystallization exothermic curve were observed for all the samples. Both of them appeared at higher times than that of PBT, indicating that the introduction of a comonomer decreased the crystallization rate. The observed dependence of this latter on composition was explained on the basis of the content of ether–oxygen atoms in diethylene and triethylene terephthalate units, and of the different sizes of these units. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 3545–3551, 2001     

Synthesis and photoluminescent properties of poly(aryl ether)s containing alternate emitting and electron‐transporting moieties

A new diphenylbutadiene‐containing bisphenol was successfully synthesized from benzylideneaniline and 4‐propenylanisole via an anil synthetic method. A series of copoly(arylene ether)s consisting of an alternate isolated blue chromophore (diphenylbutadiene) and an electron‐transporting moiety (1,3,4‐oxadiazole) was synthesized and characterized. High molecular weight copoly(arylene ether)s with an inherent viscosity of >0.5 dL/g were prepared by the nucleophilic displacement reaction of oxadiazole‐activated bis‐fluorocompounds with bisphenols. Introduction of ether linkages into the copolymers led to an enhanced solubility in organic solvents such as N,N‐dimethylacetamide (DMAc) and N‐methyl‐2‐pyrrolidinone (NMP). The resulting copolymers can be cast into tough and transparent films. The copolymers were amorphous in structure with high glass transition temperatures ranging from 182.29 to 194.50°C. They also exhibited good thermal stability with the maximum decomposition temperatures higher than 500°C in nitrogen. The absorption peaks of these copolymers in thin films varied from 375 to 391 nm, while the photoluminescent peaks varied from 410 to 433 nm. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1645–1651, 2003     

Synthesis and characterization of novel biodegradable poly(carbonate‐co‐phosphate)s

A series of aliphatic poly(carbonate‐co‐phosphate)s was synthesized in bulk using aluminium isopropoxide as initiator by ring‐opening polymerization with various cyclic carbonates (trimethylene carbonate (TMC) and 5,5‐dimethyltrimethylene carbonate (DTC)) and cyclic phosphates (ethylene ethyl phosphate (EEP), ethylene isobutyl phosphate (EIBP), ethylene lauryl phosphate (ELP) and ethylene stearyl phosphate (ESP)). The influence of reaction conditions such as polymerization time, polymerization temperature and initiator concentration on the yield and molecular weight were investigated. The substituent effect of the cyclic monomers on the polymerization was also studied, and the results indicate that the substituents exert a marked influence on the molecular weight of the copolymers obtained. The comonomer reactivity ratios were determined (TMC 0.88 and EEP 1.17). The copolymers with backbone chains rich in phosphate content exhibit better hydrophilicity than that of TMC homopolymer, and the degradation rate of the copolymers increases with the increase of phosphate content therein. © 2001 Society of Chemical Industry     

Preparation and characterization of novel crosslinked poly[glycidyl methacrylate–poly(ethylene glycol) methyl ether methacrylate] as gel polymer electrolytes

In this study, glycidyl methacrylate was copolymerized with poly(ethylene glycol) methyl ether methacrylate to obtain a copolymer {poly[glycidyl methacrylate–poly(ethylene glycol) methyl ether methacrylate] [P(GMA–PEGMA)]}, which was crosslinked with α,ω‐diamino poly(propylene oxide) (Jeffamine) at various weight ratios and molecular weights to form novel gel polymer electrolytes (GPEs). The crosslinked copolymers were characterized by Fourier transform infrared spectroscopy and thermal analysis. The crosslinked polymers were amorphous in the pristine state and became crystallized after they were doped with lithium electrolyte. Furthermore, the crosslinking degree of the crosslinked polymers increased with increasing weight ratio of Jeffamine, and both the swelling properties and mechanical behaviors of the crosslinked polymers were heavily affected by the weight ratio and molecular weight of Jeffamine. The ionic conductivity (σ) of the GPEs from the crosslinked copolymers was determined by alternating‐current impedance spectroscopy. A higher molecular weight and increased weight ratio of Jeffamine resulted in a higher σ. The GPE based on P(GMA–PEGMA) crosslinked with an equal weight of Jeffamine D2000 exhibited the highest σ of 8.29 × 10⁻⁴ S/cm at 25°C and had a moderate mechanical strength. These crosslinked copolymers could be potential candidates for the construction of rechargeable lithium batteries. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Novel copolyesters containing naphthalene structure III. Copolyesters prepared from 2,6‐dimethyl naphthalate,ethylene glycol,and 2,2‐dialkyl‐1,3‐propanediols

Poly(ethylene naphthalate) (PEN) copolymers were prepared by melt polycondensation of dimethyl naphthalate and excess ethylene glycol with 5–40 mol % (in feed) of 1,3‐propanediol or 2,2‐dialkyl‐1,3‐propanediols, where the dialkyl groups are dimethyl, diethyl, and butyl‐ethyl. No significant depression of reduced specific viscosity was observed. The comonomer contents in the copolymers are considerably higher than those in the feed. The effects of the copolymer composition on the structures of the films were investigated using thermal analyses, density measurements, X‐ray diffraction methods, and other physical tests. The crystallinities and densities of heat‐treated films decreased with increasing content of comonomer and length of alkyl side chain in the comonomer. The glass transition temperature (T_g) and melting temperature (T_m) were decreased by the copolymerization, while an increase in the length of the alkyl side chain hardly affected T_ms of the heat‐treated films. Alkali resistance, moisture resistance, dye ability, and thermal shrinkage were increased by the incorporation of comonomer having an alkyl side chain. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2754–2763, 2001     

Poly(allyl glycidyl ether)‐block‐poly(ethylene oxide): A novel promising polymeric intermediate for the preparation of micellar drug delivery systems

Novel diblock copolymers designed for the preparation of micellar drug delivery systems, consisting of hydrophobic poly(allyl glycidyl ether) (PAGE) and hydrophilic poly(ethylene oxide) (PEO), were prepared, and their self‐assembly into micellar structures was studied. Copolymers differing in the length of the polymer blocks were purified and characterized. These amphiphilic copolymers with narrow molecular weight distributions were prepared through the anionic polymerization of allyl glycidyl ether with PEO monomethyl ether sodium salt as the macroinitiator. The PAGE–PEO copolymer readily formed small micelles with narrow size distributions via simple dissolution in water. The addition of pendant double bonds to the hydrophobic part of the chain was intended for further covalent modifications. Catalytic hydrogenation, the radical crosslinking of the micelle core, and the addition of thiol to double bonds of the copolymer were examples of such modifications that were proved to proceed with a quantitative yield for this copolymer. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 95: 201–211, 2005     

In situ compatibilized SAN/LCP blends through reactive copolymers

Styrene–acrylonitrile–glycidyl methacrylate (SAG) copolymers with various contents of glycidyl methacrylate (GMA) were used to compatibilize the incompatible blends of styrene–acrylonitrile (SAN) and a liquid crystalline polymer (LCP). These SAG copolymers contain reactive glycidyl groups that are able to react with the carboxylic acid and/or hydroxyl end groups of the LCP to form the SAG‐g‐LCP copolymers during melt processing. The in situ–formed graft copolymers tend to reside along the interface to reduce the interfacial tension and to increase the interface adhesion. The morphologies of the SAN/LCP blends were examined by using scanning electron microscopy (SEM), where the compatibilized SAN/LCP blends were observed with greater numbers and finer fibrils than those of the corresponding uncompatibilized blends. The mechanical properties of the blends increased after compatibilization. The presence of a small amount (200 ppm) of ethyl triphenylphosphonium bromide (ETPB) catalyst further promotes the graft reaction and improves the compatibilization. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 3321–3332, 2001     

Ring‐opening polymerization of epichlorohydrin and its copolymerization with other alkylene oxides by quaternary catalyst system

An effective quaternary catalyst consisting of trialkyl aluminum, phosphoric acid, electron donor, and water for ring‐opening polymerization of epichlorohydrin (ECH), as well as its copolymerization with ethylene oxide (EO), propylene oxide (PO), and allyl glycidyl ether (AGE) to obtain elastomers, were studied. We investigated the optimum composition for the quaternary catalyst; the character of the catalyst; the reactivity of the four alkylene oxides during homopolymerization and copolymerization; the behavior of ECH, EO, and PO during terpolymerization; and glass transition temperatures of the copolymer and terpolymers. The results showed that the nitrogen‐containing electron donors are suitable as the third component, whereas oxygen‐containing electron donors are not. Water as the fourth component can increase the molecular weight of the homopolymer and copolymers of ECH. According to the polymerizability of tetrahydrofuran with the quaternary catalyst and the reactivity ratios of the four alkylene oxides, the quaternary catalyst was assumed to be of a coordinated anionic type. The reactivity ratios for these four alkylene oxides were determined to be EO > PO > AGE > ECH. They were verified by terpolymerization of ECH, EO, and PO. The glass transition temperature of the terpolymer exhibits a minimum value at nearly 3:1 molar ratio of PO to EO, when the molar ratio of ECH used is constant at the beginning of terpolymerization. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2446–2454, 2001     

Copolymerization and addition of styrene and N‐phenylmaleimide in the presence of nitroxide

The copolymerization and addition reaction of styrene (S) with N‐phenylmaleimide (PMI), either neat or in xylene, have been found to proceed at 125°C in the presence of 2,2,6,6‐tetramethylpiperidin‐1‐yloxy (TEMPO) radicals. TEMPO‐terminated alternating S‐PMI copolymers and comonomer adducts were obtained. The amounts of the low molecular weight compounds increased with the increasing content of PMI in the initial mixture. The reaction suggests formation of monofunctional unimolecular initiators. In the autopolymerization of neat comonomers, a mediating role of TEMPO was observed. The synthesized copolymers containing TEMPO end groups were used as macroinitiators to initiate polymerization of styrene. The molecular weight distributions of resulting poly(styrene‐alt‐N‐phenylmaleimide)‐block‐polystyrene copolymers indicated the presence of both low molecular weight termination products and some copolymer precursor. The copolymers and comonomer adducts were characterized using the nitrogen analysis, size‐exclusion chromatography (SEC), and NMR spectroscopy. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 1093–1099, 2000     

Crystallization of 2‐methyl‐1,3‐propanediol substituted poly(ethylene terephthalate). I. Thermal behavior and isothermal crystallization

Differential scanning calorimetry (DSC) was used to evaluate the thermal behavior and isothermal crystallization kinetics of poly(ethylene terephthalate) (PET) copolymers containing 2‐methyl‐1,3‐propanediol as a comonomer unit. The addition of comonomer reduces the melting temperature and decreases the range between the glass transition and melting point. The rate of crystallization is also decreased with the addition of this comonomer. In this case it appears that the more flexible glycol group does not significantly increase crystallization rates by promoting chain folding during crystallization, as has been suggested for some other glycol‐modified PET copolyesters. The melting behavior following isothermal crystallization was examined using a Hoffman–Weeks approach, showing very good linearity for all copolymers tested, and predicted an equilibrium melting temperature (T_m⁰) of 280.0°C for PET homopolymer, in agreement with literature values. The remaining copolymers showed a marked decrease in T_m⁰ with increasing copolymer composition. The results of this study support the claim that these comonomers are excluded from the polymer crystal during growth. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2592–2603, 2006     

Gamma‐irradiated metallocenic polyethylene and ethylene‐1‐hexene copolymers

The aim of this work is to present a detailed study of the changes introduced by gamma radiation on several metallocenic polyethylene copolymers. Therefore, metallocenic polyethylene and copolymers with 3.3, 9.2, and 16.1 mol % of hexene comonomer content were synthesized and irradiated with ⁶⁰Co gamma radiation under vacuum at room temperature with radiation doses ranging from 0 to 100 kGy. Size Exclusion Chromatography data show that crosslinking reactions predominate over scission, even for the copolymer with the highest tertiary carbon content. Over a certain critical dose, which depends on the molecular weight and molecular structure of the initial polymer, an insoluble gel forms. The irradiated polymers also exhibit complex rheological behavior with increasing melt viscosity and elasticity, consistent with long chain branching and/or crosslinking. FTIR confirms depletion of terminal vinyl groups and increase of trans unsaturations with dose. The rate at which these two reactions evolve seems to depend on the comonomer content of the irradiated copolymers. Differential scanning calorimetry and Raman spectroscopy analyzes indicate less crystallinity and thicker interphases in irradiated materials. A mathematical model, which accounts for scission and crosslinking reactions, fitted well the evolution with radiation dose of the measured molecular weight data. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Designing polyethylene terephthalate‐based barrier resins

We have studied the efficiencies of commercially available barrier resins used for food packaging and beverage bottle applications and compared them with resins made using copolymer and blending approaches. The effects of various copolymer related parameters that influence oxygen barrier performance and the underlying mechanisms for these effects in PET‐based copolymers and blends were investigated. Using these approaches, it is possible to make highly effective PET‐based copolymers for gas barrier applications. Blending of PET with phenolic and other organic materials shows equivalent barrier performance in PET copolymers having comonomer levels of <8‐mole %. Reduction in oxygen permeation rates results from the reduction or elimination of short range molecular motion of polyethylene terephthalate molecules. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012