4‐chloro‐3‐methylphenyl methacrylate copolymers with 2,4‐dichlorophenyl methacrylate: Synthesis,characterization, and antimicrobial activity

4‐Chloro‐3‐methylphenyl methacrylate (CMPM) and 2,4‐dichlorophenyl methacrylate (2,4‐DMA) were synthesized by reacting methacryloyl chloride with 4‐chloro‐3‐methylphenol (CMP) and 2,4‐dichlorophenol (2,4‐DP), respectively. Homo and copolymers of CMPM and 2,4‐DMA were obtained from different monomer feed ratios, using 2,2′‐azobisisobutyronitrile as initiator in toluene at 70°C. IR‐spectroscopy was employed to characterize the resulting homo and copolymers. Copolymer compositions were determined by ultraviolet (UV) spectroscopy. Fineman–Ross method was used to calculate the reactivity ratios of the monomers. Average molecular weight and polydispersity index were obtained by gel permeation chromatography (GPC). Thermogravimetric analyses (TGA) and differential thermal analysis (DTA) of copolymers were carried out under a nitrogen atmosphere. Antimicrobial effects of the homo and copolymers were also investigated for various microorganisms such as bacteria, fungi, and yeast. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100:439–448, 2006     

Synthesis of thermosensitive glycopolymers containing D‐glucose residue: Copolymers with N‐isopropylacrylamide

A new glycomonomer, 3‐acrylamido‐3‐deoxy‐1,2:5,6‐di‐O‐isopropylidene‐α‐D ‐glucofuranose, was synthesized from D ‐glucose. This monomer was homopolymerized and copolymerized with N‐isopropylacrylamide in different compositions by free‐radical polymerization. The composition of the copolymer was determined with ¹H‐NMR spectroscopy. On acid hydrolysis, water‐soluble deprotected copolymers were obtained. The protected and deprotected copolymers showed a sharp cloud‐point temperature. A linear correlation was obtained between the lower critical solution temperatures and the concentration of glycomonomer in the copolymers © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Evolutionary computing approach for evaluating flory distribution curves in gel permeation chromatography: Study of the poly(1‐octene) system

We carried out deconvolution of the molecular weight distribution curves from gel permeation chromatography for polyolefins into individual active sites considering Flory distribution by an evolutionary‐computing‐based real‐coded genetic algorithm, a nonlinear multivariate optimization algorithm. We applied the deconvolution to homopolymers of 1‐octene synthesized using heterogeneous Ziegler–Natta catalysts with different amounts of hydrogen. The molecular weight distribution was deconvoluted in to five Flory distributions, which showed a sensitivity to hydrogen amounts. With no hydrogen presence, the peaks corresponding to high‐molecular‐weight fractions were intense. As the amount of hydrogen was increased, not only did the intensities of the high‐molecular‐weight peaks decrease, but also peaks corresponding to low‐molecular‐weight fractions were observed. The method allowed us to determine the active site distribution of the polymer molecular weight distribution obtained from gel permeation chromatography. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Environmentally responsive amphiphilic cationic block copolymers synthesized by 2,2,6,6‐Tetramethylpiperidinyloxy mediated living free‐radical polymerization

Polychloromethylstyrene (PCMS)‐block‐polystyrene (PS) copolymers were prepared by controlled free‐radical polymerization in the presence of 2,2,6,6‐tetramethylpiperidinooxy and 2,2′‐azobisisobutyronitrile (AIBN) initiator. The PCMS‐b‐PS copolymers had narrow molecular weight distributions, and the block lengths were controlled by the reaction time and the molar ratios of chloromethylstyrene/AIBN and styrene/PCMS macroinitiator. The block copolymers were further quaternized with triethylamine. The amphiphilic cationic block copolymers formed colloidal particles; the effects of the pH value, salt concentration, and solvent polarity on the particle size were investigated with a dynamic light scattering analyzer. The average colloid size increased with increasing pH value and salt concentration. This implied that the colloid formed a protonated hydrophilic shell and hydrophobic styrene core in water. Furthermore, with the addition of tetrahydrofuran to the aqueous solution, the styrene segments in the core could be inverted to the outside of the colloid. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Solvothermal process for grafting dibutylmaleate onto poly(ethylene‐co‐1‐octene)

Solvothermal process was successfully developed to graft dibutylmaleate (DBM) onto poly(ethylene‐co‐1‐octene) (POE) with dicumyl peroxide (DCP) as free radical‐initiator. FTIR spectra demonstrate that DBM is successfully grafted onto the backbone of POE by this novel method. The influences of DBM content, DCP concentration, POE concentration, reaction temperature and reaction time on the grafting copolymerization have been investigated in detail through grafting degree (GD). It is worthy to indicate that high grafting degree (above 15%) can be achieved through the one‐pot way when the graft reaction is carried out in 40 mL toluene at 150°C for 5 h with 1.6 g DBM, 6–8 g POE and 0.35 g DCP. This developed solvothermal process is becoming an effective way to prepare POE‐g‐DBM graft copolymers, and can be extended to other systems. In addition, TGA results show that the thermal properties of POE are enhanced after the grafting reaction. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Reverse atom transfer radical polymerization of stearyl methacrylate using 2,2′‐azobisisobutyronitrile as the initiator

The living/controlled radical polymerization of stearyl methacrylate was carried out with a conventional radical initiator (2,2′‐azobisisobutyronitrile) in N,N‐dimethylformamide in the presence of a 2,2′‐bipyridine complex of hexakis(N,N‐dimethylformamide)iron(III) perchlorate. The polymerization mechanism was thought to proceed through a reverse atom transfer radical polymerization. The molecular weights of resulting poly(stearyl methacrylate) increased with conversion, and the resulting molecular weight distributions were quite narrow. The rates of polymerization exhibited first‐order kinetics with respect to the monomer. A probable reaction mechanism for the polymerization system is postulated to explain the observed results. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1236–1245, 2002     

High molecular weight hydrophilic functional copolymers by free‐radical copolymerization of acrylamide and of N‐acryloylmorpholine with N‐acryloxysuccinimide: Application to the synthesis of a graft copolymer

Free‐radical solution copolymerization of acrylamide (AAm) and of a disubstituted acrylamide derivative, N‐acryloylmorpholine (NAM), with N‐acryloxysuccinimide (NAS) was investigated with the aim to obtain a copolymer of at least 100,000 g mol^?1. Different polymerization conditions likely to increase the molecular weight were studied such as monomer and initiator concentrations, temperature, and nature of the solvent. The molecular weights were determined by SEC using a light‐scattering detector. The grafting of end‐functionalized polysaccharide chains onto such high molecular weight poly(NAM‐co‐NAS) was performed and a graft copolymer bearing a high number of saccharidic branches was obtained. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 1808–1816, 2003     

Synthesis and characterization of temperature‐responsive poly(vinyl alcohol)‐based copolymers

A poly(vinyl alcohol) (PVA)/sodium acrylate (AANa) copolymer was synthesized to improve the water solubility of PVA at the ambient temperature. Furthermore, a series of temperature‐responsive acetalyzed poly(vinyl alcohol) (APVA)‐co‐AANa samples of various chain lengths, degrees of acetalysis (DAs), and comonomer contents were prepared via an acid‐catalysis process. Fourier transform infrared and ¹H‐NMR techniques were used to analyze the compositions of the copolymers. The measurement of the turbidity change for APVA‐co‐AANa aqueous solutions at different temperatures revealed that the lower critical solution temperature (LCST) of the copolymers could be tailored through the control of the molecular weight of the starting PVA‐co‐AANa, DA, and comonomer ratios. Lower LCSTs were observed for APVA‐co‐AANa with a longer chain length, a higher DA, and fewer acrylic acid segments. In addition, the LCSTs of the APVA‐co‐AANa aqueous solutions appeared to be salt‐sensitive. The LCSTs decreased as the concentration of NaCl increased. Moreover, atomic force microscopy images of APVA‐co‐AANa around the LCST also proved the temperature sensitivity. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Comparison of styrene reversible addition–fragmentation chain‐transfer polymerization in a miniemulsion system stabilized by ammonlysis poly(styrene‐alt‐maleic anhydride) and sodium dodecyl sulfate

In this study, we conducted the reversible addition–fragmentation chain‐transfer (RAFT) polymerization of styrene (St) in a miniemulsion system stabilized by two different stabilizers, ammonlysis poly(styrene‐alt‐maleic anhydride) (SMA) and sodium dodecyl sulfate (SDS), with identical reaction conditions. The main objective was to compare the polymerization kinetics, living character, latex stability, and particle morphology. The macro‐RAFT agent used in both systems was SMA, which was obtained by RAFT solution polymerization mediated by 1‐phenylethyl phenyldithioacetate. The experimental results show that the St RAFT miniemulsion polymerization stabilized by SDS exhibited a better living character than that stabilized by ammonlysis SMA. The final latices were very stable in two systems, but different stabilizers had an obvious effect on the polymerization kinetics, living character, and particle morphology. All of the particles obtained by RAFT miniemulsion polymerization stabilized by SDS were solid, but an obvious core–shell structure was observed in the miniemulsion system stabilized by ammonlysis SMA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Poly(1‐octene) synthesis using high performance supported titanium catalysts

Poly(1‐octene) was synthesized by polymerization of 1‐octene using high performance MgCl₂‐supported TiCl₄ in combination with triethyl aluminum (TEAl) as cocatalyst in n‐hexane for 2 h. Two catalysts, C₁ (diester catalyst) having di‐isobutyl phthalate as internal donor and C₂ (monoester catalyst) having ethyl benzoate as internal donor were utilized for the atmospheric polymerizations to evaluate the influence of structurally different internal donors on the productivity, rate of polymerization and molecular weight profiles. The kinetic profile assessed in terms of variation of reaction parameters like temperature, cocatalyst to catalyst molar ratio and monomer concentration was found to be dependent on them. From these kinetic analyses, optimize conditions for polymerizations of 1‐octene using diester as well as monoester catalyst were elucidated. The difference in the performance of diester and monoester catalyst system can be explained in terms of stability of active titanium species and chain transfer process. NMR spectroscopy of synthesized poly(1‐octene) indicate predominantly isotactic nature. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Cationic polymerization of ethylene oxide with Maghnite‐H as a clay catalyst in the presence of ethylene glycol

The activated‐monomer cationic ring‐opening polymerization of ethylene oxide, initiated with ethylene glycol and using an acid‐exchanged montmorillonite clay called Maghnite‐H⁺ as an effective catalyst, was carried out to obtain the corresponding homopolymers with narrow polydispersity ratios. The molecular weights of the obtained polymers were controlled with the feed ratio of the monomer to the initiator. The effects of the amount of the catalyst and time on the polymerization yield and viscosity of the polymers were studied. The structure was confirmed with proton nuclear magnetic resonance and matrix‐assisted laser desorption/ionization time‐of‐flight mass spectrometry. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Kinetics of microwave‐assisted polymerization of ϵ‐caprolactone

The kinetics of polymerization of ?‐caprolactone (CL) in bulk was studied by irradiating with microwave of 350 W and frequency of 2.45 GHz with different cycle‐heating periods (30–50 s). The molecular weight distributions were determined as a function of reaction time by gel permeation chromatography. Because the temperature of the system continuously varied with reaction time, a model based on continuous distribution kinetics with time/temperature‐dependent rate coefficients was proposed. To quantify the effect of microwave on polymerization, experiments were conducted under thermal heating. The polymerization was also investigated with thermal and microwave heating in the presence of zinc catalyst. The activation energies determined from temperature‐dependent rate coefficients for pure thermal heating, thermally aided catalytic polymerization, and microwave‐aided catalytic polymerization were 24.3, 13.4, and 5.7 kcal/mol, respectively. This indicates that microwaves increase the polymerization rate by lowering the activation energy. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 1450–1456, 2004     

Preparation and application of sulfonated poly(1‐octene‐co‐styrene)

In this article, 1‐octene and styrene was copolymerized by the supported catalyst (TiCl₄/ID/MgCl₂). Subsequently, by sulfonation reaction, sulfonated poly(1‐octene‐co‐styrene)s which were amphiphilic copolymers were prepared. The copolymerization behavior between 1‐octene and styrene is moderate ideal behavior. Copolymers prepared by this catalyst contain appreciable amounts of both 1‐octene and styrene. Increase in the feed ratio of styrene/1‐octene leads to increase in styrene content in copolymer and decrease in molecular weight. As the polymerization temperature increases, the styrene content in the copolymers increases, however, the molecular weight decreases. Hydrogen is an efficient regulator to lower the molecular weights of poly(1‐octene‐co‐styrene)s. The sulfonation degree of the sulfonated poly(1‐octene‐co‐styrene)s increased as the styrene content in copolymer increased or the molecular weight decreased. Thirty‐six hour is long enough for sulfonation reaction. The sulfonated poly(1‐octene‐co‐styrene)s can be used as effective and durable modifying agent to improve the wettability of polyethylene film and have potential application in emulsified fuels and for the stabilization of dispersions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Effect of the chain‐transfer‐agent content on the emulsion polymerization process and adhesive properties of poly(n‐butyl acrylate‐co‐acrylic acid) latexes

The effect of water on regenerated silkworm silk fibers has been studied and compared with that of water on natural silkworm silk fibers. Regenerated fibers are spun from an N‐methylmorpholine‐N‐oxide (NMMO) fibroin solution through a wet‐spinning process, leading to fibers with two distinct tensile behaviors, labeled as brittle and ductile, respectively. Regenerated fibers show a significant contraction when immersed in water. Contraction increases further after drying. In contrast, natural silkworm silk fibers show a negligible contraction when submerged in water. Regenerated fibers tested in water are considerably more compliant than samples tested in air, though their stiffness and tensile strength are significantly reduced. It has been shown that the tensile properties of brittle regenerated fibers can be modified by a wet‐stretching process, which consists of deforming the fiber while immersed in water. Regenerated wet‐stretched fibers always show a ductile behavior independent from their initial tensile behavior. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Nitroxide‐mediated homopolymerization and copolymerization of 2‐vinylpyridine with styrene

Homopolymerization and copolymerization of 2‐vinylpyridine (2VP) with styrene (S) at 125°C in the presence of 2,2,6,6‐tetramethyl piperidin‐1‐yloxyl (TEMPO) radicals have been studied. The homopolymerization was carried out with 2,2′‐azobis(isobutyronitrile) (AIBN) as a thermal initiator or without AIBN in the initial reaction mixture. In the copolymerization initiated with AIBN, the molar fraction of 2VP in the feed, F_2VP, varied in the range of 0.1–0.9; F_2VP = 0.65 was found to be the azeotropic composition. The linear semilogarithmic time–conversion plots demonstrated a pseudoliving nature of the polymerizations under study. The molecular weight–conversion dependences indicated the participation of side reactions, diminishing the number of TEMPO‐terminated polymer chains. The synthesized homopolymers and copolymers were characterized using size‐exclusion chromatography (SEC), nitrogen analysis, and NMR spectroscopy. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 2024–2030, 2001     

New fluorous bipyridine ligands for copper‐catalyzed atom transfer radical polymerization of methyl methacrylate in the thermomorphic mode

The atom transfer radical polymerization (ATRP) of methyl methacrylate (MMA) is often carried out under homogeneous conditions, so the residual metal catalyst in the polymer often influences the quality of the polymer and causes environmental pollution in the long run. Novel CuBr/4,4′‐bis(R_fCH₂OCH₂)‐2,2′‐bpy complexes (R_f = n‐C₉F₁₉, n‐C₁₀F₂₁, or n‐C₁₁F₂₃; 2,2′‐bpy = 2,2′‐bipyridine) are insoluble in toluene at room temperature yet readily dissolve in toluene at elevated temperatures to form homogeneous phases for use as catalysts in the ATRP reaction, and the Cu complexes precipitate again upon cooling. The CuBr/4,4′‐bis(n‐C₉F₁₉CH₂OCH₂)‐2,2′‐bpy system produced the best results (e.g., polydispersity index by gel permeation chromatography = 1.26–1.41), in that the residual Cu content in the polymer was as low as 19.3 ppm when the ATRP of MMA was carried out in the thermomorphic mode. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Preparation of nanoclay‐dispersed polystyrene nanofibers via atom transfer radical polymerization and electrospinning

In this study, clay‐dispersed polystyrene (PS) nanocomposites were prepared with the in situ atom transfer radical polymerization method and were subsequently electrospun to form nanofibers 450–650 nm in diameter. The polymer chains extracted from the clay‐dispersed nanofibers exhibited a narrow range of molecular weight distribution. Thermogravimetric analysis (TGA) confirmed a higher thermal stability of the resulting nanocomposites compared to PS. The effect of the weight ratio of montmorillonite on the thermal properties of the nanocomposites was also studied by TGA. Differential scanning calorimetry revealed that the addition of the nanoclay increased the glass‐transition temperature. Moreover, degradation of the bromide chain‐end functionality took place at low temperatures. Scanning electron microscopy showed that the average diameter of the fibers was around 500 nm. The dispersion of clay layers was also evaluated by Al atoms in the PS matrix with the energy‐dispersive X‐ray detection technique. Transmission electron microscopy confirmed the exfoliation of the nanoclay within the matrix. However, the clay layers were oriented along the nanofiber axis. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Preparation of poly(tert‐butyl acrylate)‐poly(acrylic acid) amphiphilic copolymers via radiation‐induced reversible addition–fragmentation chain transfer mediated polymerization of tert‐butyl acrylate

Poly(tert‐butyl acrylate) (PtBA) is a versatile hydrophobic macromolecule usually preferred in the development of new materials for a host of applications. PtBA homopolymers with well‐defined structure and controlled molecular weight in a wide range were successfully synthesized via radiation‐induced reversible addition–fragmentation chain transfer (RAFT) polymerization in the presence of a trithiocarbonate type RAFT agent. The polymerization of tBA was performed under ⁶⁰Co γ‐irradiation in the presence of 2‐(dodecylthiocarbonothioylthio)‐2‐methylpropionic acid (DDMAT) as the RAFT agent in toluene at room temperature with three [tBA]/[DDMAT] ratios (400, 600 and 1000) and different irradiation times. Radiation‐induced polymerization of tBA displayed controlled free radical polymerization characteristics: a narrow molecular weight distribution (M_w/M_n ~ 1.1), pseudo first order kinetics and controlled molecular weights. The system followed the RAFT polymerization mechanism even at very low amounts of RAFT agent ([tBA]/[DDMAT] = 1000), and molecular weights up to 113 900 with narrow dispersity (Ð =1.06) were obtained. PtBA was further hydrolysed into different amphiphilic PtBA‐co‐poly(acrylic acid) (PAA) copolymers by low (27.5%) and high (77.3%) degrees of hydrolysis. The pH sensitivity of the two copolymers was investigated by dynamic light scattering at pH 2 and pH 9 (above and below the pK_a value of PAA) and their hydrodynamic diameters and zeta potential values were determined. © 2020 Society of Chemical Industry     

Toughening of epoxy resins by hydroxy‐terminated,silicon‐modified polyurethane oligomers

Epoxy resins are among the most versatile engineering structural materials. A wide variety of epoxy resins are commercially available, but most are brittle. Several approaches have been used to improve the toughness of epoxy resins, including the addition of fillers, rubber particles, thermoplastics, and their hybrids, as well as interpenetrating polymer networks (IPNs) of acrylic, polyurethane, and flexibilizers such as polyols. This last approach has not received much attention; none of them have been able to suitably increase resin toughness with out sacrificing tensile properties. Therefore, in an attempt to fill this gap, we experimented with newly synthesized hydroxy‐terminated silicon‐modified polyurethane (SiMPU) oligomers as toughening agents for epoxy resins. SiMPU oligomers were synthesized from dimethyl dichlorosilane, poly(ethylene glycol) (weight‐average molecular weight ～ 200), and toluene 2,4‐diisocyanate and characterized with IR, ¹H‐NMR and ¹³C‐NMR, and gel permeation chromatography. The synthesized SiMPU oligomers, with different concentrations, formed IPNs within the epoxy resins (diglycidyl ether of bisphenol A). The resultant IPN products were cured with diaminodiphenyl sulfone, diaminodiphenyl ether, and a Ciba–Geigy hardener under various curing conditions. Various mechanical properties, including the lap‐shear, peel, and impact strength, were evaluated. The results showed that 15 phr SiMPU led to better impact strength of epoxy resins than the others without the deterioration of the tensile properties. The impact strength increased continuously and reached a maximum value (five times greater than that of the virgin resin) at a critical modifier concentration (20 phr). The critical stress intensity factor reached 3.0 MPa m^1/2 (it was only 0.95 MPa m^1/2 for the virgin resin). © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1497–1506, 2003     

RAFT‐mediated graft polymerization of glycidyl methacrylate in emulsion from polyethylene/polypropylene initiated with γ‐radiation

The successful reversible addition‐fragmentation (RAFT)‐mediated graft polymerization of glycidyl methacrylate (GMA) in emulsion phase from polyethylene/polypropylene nonwoven fabric using 4‐cyano‐4‐[(phenylcarbonothioyl)thio]pentanoic acid under γ‐irradiation at ambient condition is reported. While conventional graft polymerization in emulsion phase yielded grafted materials with low of grafting (Dg) values [<7.5% at 10% (wt/wt) GMA], addition of RAFT agent to the graft polymerization system allowed the synthesis of polyethylene/polypropylene‐g‐poly(GMA) with more tunable Dg (8% ≤ Dg ≤ 94%) by controlling the grafting parameters. Relatively good control (PDI ～1.2 for selected grafting conditions) during polymerization was attained at 100:1 monomer‐to‐RAFT agent molar ratio. The number average molecular weight of free poly(glycidyl methacrylate) (PGMA) increased as a function of monomer conversion. NMR analyses of the free PGMA homopolymers indicate the presence of dithiobenzoate group from 4‐cyano‐4‐((phenylcarbonothioyl)thio) pentanoic acid on the polymer chain. The reactive pendant oxirane group of the grafted GMA can be modified for various environmental and industrial applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45270.