Graft copolymerization of methyl acrylate onto poly(vinyl alcohol) initiated by potassium diperiodatoargentate(III)

The graft copolymerization of methyl acrylate onto poly(vinyl alcohol) (PVA) using potassium diperiodatoargentate(III) [Ag(III)]–PVA redox system as initiator was studied in an alkaline medium. Some structural features and properties of the graft copolymer were confirmed by Fourier‐transfer infrared spectroscopy, scanning electron microscope, X‐ray diffraction and thermogravimetric analysis. The grafting parameters were determined as a function of concentrations of monomer, initiator, macromolecular backbone (X?_n = 1750, M? = 80 000 g mol^?1), reaction temperature and reaction time. A mechanism based on two single‐electron transfer steps is proposed to explain the formation of radicals and the initiation profile. Other acrylate monomers, such as methyl methacrylate, ethyl acrylate and n‐butyl acrylate, were also used to produce graft copolymerizations. It has been confirmed that grafting occurred to some degree. Thermogravimetric analysis was performed in a study of the moisture resistance of the graft copolymer. Copyright © 2004 Society of Chemical Industry     

Graft copolymerization of methyl acrylate onto poly(vinyl alcohol) initiated by potassium diperiodatonickelate(IV)

The graft copolymerization of methyl acrylate onto poly(vinyl alcohol) (PVA) with a potassium diperiodatonickelate(IV) [Ni(IV)]–PVA redox system as an initiator was investigated in an alkaline medium. The grafting parameters were determined as functions of the temperature and the concentrations of the monomer and initiator. The structures of the graft copolymers were confirmed by Fourier transform infrared spectroscopy, scanning electron microscopy, X‐ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. The Ni(IV)–PVA system was found to be an efficient redox initiator for this graft copolymerization. A single‐electron‐transfer mechanism was proposed for the formation of radicals and the initiation. Other acrylate monomers, such as methyl methacrylate, ethyl acrylate, n‐butyl acrylate, and n‐butyl methacrylate, were used as reductants for graft copolymerization. These reactions definitely occurred to some degree. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 529–534, 2003     

微波辐射吸油性复合体的制备及性能研究

以甲基丙烯酸丁酯、丙烯酸β－羟乙酯、丙烯酸－２－乙基己酯为单体,ＢＰＯ为引发剂,二甲基丙烯酸二乙醇酯为交联剂,无纺布为基材,在微波辐射下分别合成甲基丙烯酸丁酯与丙烯酸β－羟乙酯的共聚复合吸油体及丙烯酸－２－乙基己酯与丙烯酸β－羟乙酯共聚复合吸油体。并考察了单体配比、引发剂用量、交联剂用量、微波辐射功率诸因素对高吸油性复合体的性能影响,从而制得了性能优异的吸油复合体。     

Grafting of iPP powder with methacrylate monomers in water medium

The grafting of different methacrylates on iPP in the solid state has been studied under various reaction conditions using a radical initiation. Three peroxides and five grafting agents representing methyl‐, ethyl‐, butyl‐, ethyl hexyl‐, and dodecyl methacrylate were tested. The grafting efficiency (GE) performed in water medium (slurry) as possible heat transfer medium was compared with the GE obtained without using water. The iPP powder was first impregnated with monomer and peroxide initiator and then water solution of NaCl was added. Obtained GEs were much higher for all peroxides and monomers used when compared with GE performed without water. Quantity of grafted monomer was determined by Fourier transform infrared spectroscopy (FTIR). The products were characterized by differential scanning calorimetry (DSC) and surface energies of grafted iPP films were measured. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Optimized condition for grafting reaction of poly(butyl acrylate) onto oil palm empty fruit bunch fibre

Preparation of poly(butyl acrylate)‐grafted oil palm empty fruit bunch fibre (OPEFB) has been successfully carried out using H₂O₂/Fe²⁺ as a redox initiator in aqueous solution. The effects of reaction temperature and period, as well as the amount of monomer, initiator and nitric acid, on the percentage of grafting were investigated. The percentage of grafting increases with amount of monomer and can be controlled by setting the appropriate reaction conditions. The maximum percentage of grafting (about 265%) was obtained when the reaction was carried out without acid under optimum conditions (reaction period: 2 h, reaction temperature: 55 °C, amount of H₂O₂: 5.88 mmol) with 42.2 mmol of monomer. Mechanisms of grafting of butyl acrylate onto OPEFB were proposed. Characterization of the grafted OPEFB was done by Fourier‐transform infrared spectroscopy and scanning electron microscopy. The thermal properties were studied by thermogravimetric analysis. Copyright © 2003 Society of Chemical Industry     

Synthesis of fiber crosslinking cationic latex and its effect on surface properties of paper

Series of fiber cross-linking cationic latexes containing both epoxy and quaternary ammonium groups were synthesized in the presence of styrene/butyl acrylate/steary methacrylate/dimethyl amino ethyl methacrylate/epichlorohydrin (SBSDE). The chemical structure and composition of SBSDE were confirmed by ¹H nuclear magnetic resonance spectrum (¹H NMR), Fourier transforms infrared (FTIR), gel permeation chromatography (GPC) analyses. Latexes were subsequently used as sizing agents and surface properties (water resistance, surface strength, burst strength, whiteness, and tensile strength) of paper were examined and compared. Results revealed that SBSDE was a potential candidate for emulsion polymerization. Monomer ratio, initiator type, and SBSDE content determined the properties of latexes and strongly affected the sizing performance. The superior surface sizing agent was obtained by using 2,2-azobisisobutyronitrile as the initiator, when the concentration of SBSDE was 8.5 wt%, the butyl acrylate (BA)/styrene (St) ratio was 0.85.     

Codiluent effect on the properties of UV-cured films

Different formulations were developed with an urethane oligomer combined with a number of reactive diluents with different functionalities such as N-vinylpyrrolidone (monofunctional), butanediol diacrylate (difunctional), tripropylene glycol diacrylate (difunctional), and trimethylolpropane triacrylate (trifunctional). The films were prepared with these formulations and cured under UV radiation in the presence of the photoinitiator Irgacura 184. Their properties were characterized. The effect of codiluents of low glass transition temperatures like ethyl hexyl acrylate and methoxyethyl acrylate on the properties of these films was studied. These formulations were then applied as thin coatings on the leather surface in order to study the improvement of the leather substrate. Both tensile strength and elongation of the treated leather increased. The gloss of the coated leather was also enhanced. Incorporation of a plasticizer into these systems substantially improved the rheological properties of the coated leather. © 1995 John Wiley & Sons, Inc.     

Dyeing of chrome tanned collagen modified by in situ grafting with 2‐EHA and MAC

The aim of this study deals with the modification of the chrome tanned collagen (leather) by in situ grafting with 2‐ethyl hexyl acrylate (2‐EHA) and methacrylic acid (MAC) to improve its dyeability using Amecid Floxine 2GN (C.I. Acid Red 1) and Remazol Black B (C.I. Reactive Black 5). The optimum condition of in situ grafting has been evaluated. FTIR spectra of the ungrafted and the in situ grafted chrome tanned collagen showed that the corresponding band of the acrylate carbonyl ester occurs at 1730–1735 cm^?1 when compared with the ungrafted ones. The colorimetric data of the in situ grafted and dyed samples exhibited improvement in color shade, dye bath exhaustion, wash and light fastness relative to the ungrafted and dyed ones. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 174–179, 2006     

Synthesis and application of methyl methacrylate/butyl acrylate copolymer nanoemulsions as efficient retanning and lubricating agents for chrome‐tanned leather

Two different nano‐emulsions based on methyl methacrylate/butyl acrylate copolymers have been synthesized to be used as retanning and lubricating agents for chrome‐tanned leather. The main difference and characteristics of the two prepared copolymers were studied. The nano particle size of the two copolymers was confirmed using transmission electron microscope (TEM). The influence of the prepared copolymers on chrome‐tanned leather as retanning agents was investigated. The properties of the retanned leather, namely, physicomechanical properties as tensile strength, elongation at break and water absorption, were measured. Thermal gravimetric analysis (TGA) technique was used to examine the thermal stability of the retanned leather. Also, the texture of the grain surface and fibers were inspected using scanning electron microscope (SEM). The retanned leather showed an improvement in its physicomechanical properties, as well as enhancement of its thermal stability as compared with the chrome‐tanned leather. Furthermore, the retanned leather has uniform dyestuff, softness, and firmness of grain. All these promising results provide evidence to the applicability of the prepared copolymer emulsions as efficient retanning and lubricating agents for chrome‐tanned leather. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Graft copolymerization of wool using acrylate monomers. I. Optimum conditions of grafting and molecular weight of grafts

Wool fibres were grafted with methyl acrylate, ethyl acrylate, n-butyl acrylate and methylmethacrylate to various percentages of grafting in nitrogen atmosphere using ceric ammonium nitrate in nitric acid as initiator. The effects of concentration of the initiator, acid, monomer, temperature and time on the grafting were investigated. A comparison of such results indicated the following reactivity order of monomers: methyl acrylate > ethyl acrylate > methylmethacrylate > n-butyl acrylate. The molecular weights of the grafts were investigated by isolating the grafts from the fibres.     

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

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

Synthesis and properties of amphiphilic copolymers of butyl acrylate and methyl methacrylate with uniform polyoxyethylene grafts

Amphiphilic copolymers of butyl acrylate (BA) and methyl methacrylate (MMA) with uniform polyoxyethylene (PEO) grafts were synthesized by the copolymerization of BA and MMA with a methacrylate‐terminated PEO macromer in benzene with azobisisobutyronitrile as an initiator. The effects of various copolymerization conditions on the grafting efficiency and molecular weight of the copolymers, as well as the effect of the copolymerization time on the conversions of the macromer and the monomers, were reported. The copolymers, with uniform PEO grafts, were purified by successive extractions with water and ether/acetone (3/7) to remove unreacted macromer and ungrafted copolymers of MMA and BA, respectively. The purified graft copolymers were characterized with IR, ¹H‐NMR, membrane osmometry, gel permeation chromatography, and differential scanning calorimetry. The highest grafting efficiency was about 90%, and molecular weight of the copolymers varied around 10⁵. The average grafting number of the copolymer was about 10. A study of the crystalline properties, emulsifying properties, phase‐transfer catalytic ability, and mechanical properties of the graft copolymers showed that the emulsifying volume decreased with the increasing molecular weight of the PEO grafts but increased with the PEO content. The conversion of potassium phenolate in the Williamson solid–liquid reaction obviously increased with an increasing PEO content of the graft copolymers. The crystallinity of the graft copolymers increased with the PEO content of the graft copolymers or the molecular weight of the macromer used. The copolymers, prepared under certain conditions, behaved as thermoplastic elastomers. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2982–2988, 2003     

Viscoelastic properties of branched polyacrylate melts

The viscoelastic properties of poly(n‐butyl acrylate), poly(ethyl acrylate) and poly(methyl acrylate) melts have been studied using samples that varied in both molar mass and the mol% branched repeat units, these properties having been previously determined by gel permeation chromatography and ¹³C NMR spectroscopy, respectively. Poly(n‐butyl acrylate) was studied most extensively using seven samples; one sample of poly(n‐butyl acrylate), two samples of poly(ethyl acrylate) and one sample of poly(methyl acrylate) were used to study the effect of side‐group size. Storage and loss moduli were measured over a range of frequency (1 × 10^?3 to 1 × 10² rad s^?1) at temperatures from T_g + 20 °C to T_g + 155 °C and then shifted to form master curves at T_g + 74 °C through use of standard superposition procedures. The plateau regions were not distinct due to the broad molar mass distributions of the polyacrylates. Hence, the upper and lower limits of shear storage modulus from the nominal ‘plateau’ region of the curves for the seven poly(n‐butyl acrylate) samples were used to calculate the chain molar mass between entanglements, M_e, which gave the range 13.0 kg mol^?1 < M_e < 65.0 kg mol^?1. The Graessley–Edwards dimensionless interaction density and dimensionless contour length concentration were calculated for poly(n‐butyl acrylate) using the mean value of plateau modulus (1.2 × 10⁵ Pa) and three different methods for estimation of the Kuhn length; the data fitted closely to the Graessley–Edwards universal plot. The Williams–Landel–Ferry C₁ and C₂ parameters were determined for each of the polyacrylates; the data for the poly(n‐butyl acrylate) samples indicate an overall reduction in C₁ and C₂ as the degree of branching increases. Although the values of C₁ and C₂ were different for poly(n‐butyl acrylate), poly(ethyl acrylate) and poly(methyl acrylate), there is no trend for variation with structure. Thus the viscoelastic properties of the polyacrylate melts are similar to those for other polymer melts and, for the samples investigated, the effect of molar mass appears to dominate the effect of branching. © 2001 Society of Chemical Industry     

Studies on the polyblends of poly(vinyl chloride) with various methacrylate copolymers,physical and mechanical properties. I

The effect of blending various methacrylate copolymers on the physical and mechanical properties of poly(vinyl chloride) (PVC) has been investigated. Copolymers of methylmethacrylate with methylacrylate, ethyl acrylate, butyl acrylate, and 2-ethylhexyl acrylate in 80:20 and 50:50 wit methylmethacrylate have been prepared and characterized by nuclear magnetic resonance spectroscopy. Polyblends of PVC and such polyacrylates have been prepared in 80:20 ratio by melt blending technique and characterized by thermomechanical analysis to study the glass transition behavior vis-à-vis the compatibility of these blends. Mechanical properties of these blends revealed a substantial increase in impact strength particularly when long chain acrylate polymers like butyl acrylate and 2-ethyl hexyl acrylates are used; however, there is a decrease in the yield stress and initial modulus. A shift from brittle failure to ductility has been observed in blends of PVC on incorporation of these acrylate copolymers. Scanning electron microscopic studies have been carried out to support these observations.     

聚丙烯酸酯的乳液聚合及其吸油性能研究

以丙烯酸十二酯、丙烯酸丁酯等为原料,采用乳液聚合法合成了聚丙烯酸酯树脂。讨论了乳化剂、搅拌速度、反应温度对聚丙烯酸酯乳液性能的影响,考察了单体配比、引发剂用量、交联剂种类及用量、致孔剂用量等对聚丙烯酸酯树脂吸油性能的影响。发现当反应单体丙烯酸丁酯与丙烯酸十二酯的摩尔比为3∶1,交联剂二乙烯基苯用量为单体质量的2%,引发剂过硫酸铵用量为单体质量的2%,致孔剂乙酸乙酯用量为单体质量的50%时,合成的聚丙烯酸酯树脂对煤油、甲苯和CCl4的吸收率分别为7.12、18.10和33.39g·g-1,表现出良好的吸油性能。     

Thermal and swelling studies of hydrophobically modified polyacrylamide hydrogels

Hydrophobically modified polyacrylamide hydrogels were prepared by polymerizing acrylamide, using n‐butyl acrylate and 2‐ethyl hexyl acrylate as comonomers and dimethyl formamide as a solvent. We report here for the first time that the Alfred Q‐e reactivity ratios are matching with the experimental value (elemental analysis result) for the terpolymer hydrogel systems. Differential scanning calorimetry (DSC) thermograms of the hydrogel samples revealed two endothermic transitions, one near 0°C, corresponding to the melting transition of ice and another above ambient temperature. This high temperature transition is due to the rearrangement of water molecules engaged in hydrophobic hydration surrounding the hydrophobic groups (alkyl side chains). This depends on the type of hydrophobic groups and the gel compositions. Swelling and deswelling studies of the gels were performed using various solvents such as water and isopropyl alcohol. An abnormally high swelling and deswelling behavior was observed in the homopolymer gels and the gels with low amount of hydrophobic comonomers. This could be attributed to the more intramolecular cross‐linked structure formed during synthesis in organic solvent. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Hydrophobic cellulose fibers via ATRP and their performance in the removal of pyrene from water

In the present work, cellulose fibers were modified by grafting with poly(lauryl acrylate) and poly(octadecyl acrylate). The grafted materials were prepared by polymerization of the corresponding monomers via surface initiated atom transfer radical polymerization, starting from cellulose papers previously modified with 2‐bromoisobutyryl groups. The polymerizations were carried out in the presence of ethyl‐2‐bromoisobutyrate, as a sacrificial initiator, added to control the molecular weight of the anchored segments, and polymerization kinetics. The grafting of both polymers was confirmed by infrared spectroscopy and elemental analysis. The effect of grafting these polymers on the thermal stability, morphology, and surface properties of cellulose fibers was studied using thermogravimetric analysis, scanning electron microscopy, and measuring water contact angle, respectively. The results reveal that grafting poly(lauryl acrylate) and poly(octadecyl acrylate) to cellulose confers the filter paper a hydrophobic character, and increases its affinity with pyrene, allowing the removal of this pollutant from water. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44482.     

Grafting onto wool,XVII. Graft copolymerization of methyl acrylate and ethyl acrylate by use of VO(acac)2 as initiator. Comparison of monomer reactivities

Graft copolymerization of acceptor monomers methyl acrylate and ethyl acrylate onto Himachali wool fiber has been studied in aqueous medium by using vanadium oxyacetyl acetonate as initiator at 40, 50, 60, and 70°C. Graft copolymerization was carried out for various reaction periods and nitric acid was found to catalyse the reaction. Percentage of grafting and percent efficiency have been determined as functions of concentration of nitric acid, concentration of initiator, concentration of monomer, time, and temperature. Under optimum conditions, methyl acrylate and ethyl acrylate afforded maximum grafting to the extent of 28.4 and 18.5%, respectively. Relative reactivities of methyl acrylate and ethyl acrylate towards grafting have been compared with those of methyl methacrylate, acrylic acid and vinyl acetate reported earlier from this laboratory. Different vinyl monomers showed the following reactivity order: MMA > MA > EA > AAc > VAc. Several grafting experiments were carried out in the presence of various additives which included tert-butylhydroperoxide (TBHP), dimethylsulfoxide, pyridine, and dimethylformamide. Only TBHP was found to enhance grafting to a considerable extent, other additives decrease percent grafting of both methyl acrylate and ethyl acrylate.     

New polymeric materials for paper and textile conservation. I. Synthesis and characterization of acrylic copolymers

In the preservation of cultural heritage items, the use of polymeric materials for the consolidation and protection of artifacts with historical and artistic value is widely accepted. This area is vast and includes studies of various objects made of different materials such as wood, stone, textiles, and paper. The aim of this article is to establish the most suitable copolymer for cellulose‐based‐material restoration according to its properties, as evaluated by several techniques such as ¹H‐NMR spectroscopy, size exclusion chromatography, differential scanning calorimetry, and dynamic mechanical analysis. In addition to the mechanical property evaluation, an investigation of fungal deterioration has been carried out. Because, in the literature, no complete study concerning the characterization of ethyl acrylate/methyl methacrylate and butyl acrylate/methyl methacrylate copolymers is available, a detailed and full investigation of these polymers is required before the best copolymer is selected for grafting polymerization onto cellulose. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 1157–1164, 2005     

Polymers from renewable resources. I. Castor oil-based interpenetrating polymer networks: Thermal and mechanical properties

A number of polyurethanes (PUs) were synthesized by reacting castor oil with toluene-2,4-diisocyanate and hexamethylene diisocyanate and varying the NCO/OH ratio. All these polyurethanes were reacted with some acrylic monomers like ethyl acrylate, n-butyl acrylate, ethyl methacrylate, and butyl methacrylate using a crosslinker ethylene glycol dimethyl-acrylate and benzoyl peroxide as the initiator. The physicochemical properties of interpenetrating polymer networks (IPNs) are reported. Thermogravimetric analysis was used to study the thermal behavior of IPNs and the evaluation of kinetic parameters. Degradation mechanism has also been investigated. Some of the mechanical properties viz. tensile strength, shore-A hardness, elongation at break, etc. are also reported. © 1993 John Wiley & Sons, Inc.