Radiation‐induced graft polymerization of glycidyl methacrylate onto PE/PP nonwoven fabric and its modification toward enhanced amidoximation

A nonwoven fabric made of polypropylene coated by polyethylene was used as the trunk polymer in the preparation of a highly efficient new adsorbent. Metal ion uptake capacity has been aimed to be increased by introducing double amidoxime groups per repeating unit of the chains grafted to trunk polymer. The base polymer was irradiated by electron beams with a dose of 200 kGy under N₂ atmosphere and glycidyl methacrylate (GMA) was grafted onto irradiated nonwoven fabric. Grafting conditions were optimized, and GMA‐grafted polymer was modified with 3,3′‐iminodipropionitrile in ethanol at 80°C. GMA grafting (150%) was determined to be the optimum degree given that higher extent of grafting rendered the materials brittle. Pendant nitrile groups were then amidoximated by using 6% hydroxylamine in methanol–water mixture (1 : 1). The all‐polymeric structures were characterized by using FTIR, SEM, and thermal analysis methods, confirming the grafting, modification, and amidoximation stages gravimetrically, spectroscopically, and visually. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Improvement of autohesive and adhesive properties of polyethylene plates by photografting with glycidyl methacrylate

Glycidyl methacrylate (GMA) was photografted with the low‐ and high‐density polyethylene (LDPE and HDPE) plates to provide their surfaces with autohesive and adhesive properties. The chemical composition and wettability of the GMA‐grafted LDPE and HDPE (LDPE‐g‐PGMA and HDPE‐g‐PGMA) plates remained constant above full coverage of the surfaces with grafted PGMA chains. Autohesive strength obtained with 1,4‐dioxane as a good solvent of PGMA increased with an increase in the grafted amount and substrate breaking was observed at the grafted amount of 117 μmol/cm². The grafted amount at substrate breaking was decreased by increasing the temperature and load during heat pressing. Adhesive strength was effectively enhanced by use of multi‐functional amine compounds because of the increase in the reaction between primary or secondary amine groups and epoxy groups appended to the grafted PGMA chains. In addition, the decrease in the amine compound concentration and the increase in the number of amino groups in the amine compounds used led to the decrease in the grafted amounts at substrate breaking. Substrate breaking occurred at lower grafted amounts for the HDPE‐g‐PGMA plates than for the LDPE‐g‐PGMA plates because the location of the photografting was restricted to the outer surface region for the HDPE plate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 493–500, 2007     

Tribological behavior of epoxy composites containing reactive SiC nanoparticles

The present article evaluated the sliding wear behaviors of epoxy and its composites filled with SiC nanoparticles. Polyglycidyl methacrylate (PGMA) and a copolymer of glycidyl methacrylate and styrene were grafted onto the nanoparticles as a measure of surface pretreatment, respectively. The grafted polymers were selected because the epoxide groups on PGMA would take part in the curing reaction of epoxy resin and covalently connect the nanoparticles with the matrix, while styrene acted as a copolymerized monomer to adjust the amount of the reactive groups of the grafted macromolecular chains, and hence the compatibility between the grafted polymers and the matrix. In comparison to the composites filled with untreated nano‐SiC particles, the composites with the grafted nano‐SiC exhibit improved sliding wear resistance and reduced frictional coefficient owing to the chemical bonding at the filler/matrix interface. The results were analyzed in terms of structure‐properties relationship of the composites. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 2608–2619, 2007     

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.     

Preparation of iminodiacetic acid-type composite chelating material IDAA-PGMA/SiO2 and preliminary studies on adsorption behavior of heavy metal ions and rare earth ions

A kind of iminodiacetic acid (IDAA)-type composite chelating materials was prepared by first graft polymerization and subsequent polymer reaction. Monomer glycidyl methacrylate (GMA) was grafted on micron-sized silica gel particles in the manner of “graft through” in a solution polymerization system, resulting in the grafted particles poly(glycidyl methacrylate) (PGMA)/silicon dioxide (SiO₂). Subsequently, the ring-opening reaction of the epoxy groups of the grafted PGMA was carried out with IDAA as reaction reagent, resulting in the bonding of IDAA groups onto PGMA/SiO₂ and obtaining the composite chelating material IDAA-PGMA/SiO₂ particles. The effects of the main factors on the graft polymerization of GMA and the bonding reaction of IDAA were examined emphatically, and the adsorption behavior of IDAA-PGMA/SiO₂ particles toward several kinds of heavy metal ions and rare earth ions was preliminarily explored. The experiments results show that: (a) to obtain the grafted particles PGMA/SiO₂ with high grafting degree, in the graft polymerization step, the reaction temperature and the used amount of initiator should be controlled. The suitable temperature is 70°C and the appropriate used amount of initiator is 1.4 % of the monomer mass. Under the optimal conditions, the grafted degree of PGMA can reach 17.50 g/100 g. (b) It is feasible to introducing of IDAA groups onto PGMA/SiO₂ particles via ring-opening reaction of epoxy groups of the grafted PGMA under alkaline conditions, and the bonding rate of IDAA group can get up to 70% based on epoxy groups of the grafted PGMA. (c)The composite chelating material IDAA-PGMA/SiO₂ possesses very strong chelating adsorption ability for heavy metal ions, and especially toward Pb²⁺ ion, the adsorption capacity can reach 24 g/100 g. (d) The adsorption ability of IDAA-PGMA/SiO₂ for rare earth ions is weaker than that for heavy metal ions. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

D301树脂的胺基化改性及其对AuCl4-的吸附性能

以D301树脂表面的胺基与过硫酸铵构成氧化-还原引发体系,将单体甲基丙烯酸缩水甘油酯(GMA)接枝聚合到D301树脂表面,制得接枝材料D301-g-PGMA;通过聚甲基丙烯酸缩水甘油酯(PGMA)分子链上的环氧基团与乙二胺中胺基的开环反应,实现接枝材料的胺基化改性,制得吸附材料D301-g-APGMA,考察了接枝聚合条件对接枝率的影响及胺基化反应条件对胺基含量的影响,对材料的结构进行了表征,研究了其对AuCl4-的吸附性能. 结果表明,在GMA用量10 mL、过硫酸铵为单体质量的1.5%及40℃条件下反应18 h, PGMA接枝率达41.15%. 胺基化改性时,在90℃下反应8 h,D301-g-PGMA上环氧键的开环率达91.67%. 改性后D301-g-APGMA对AuCl4-的吸附能力比D301树脂有较大提升,吸附容量达276.74 mg/g. D301-g-APGMA具有良好的再生与重复使用性能.     

Preparation of epoxy functionalized PP with unique structure and its post‐ring open reaction

This article discusses a convenient chemical approach named in situ chlorination graft copolymerization (ISCGC) to prepare epoxy functionalized isotactic polypropylene (iPP) with a unique structure. This method was carried out in the gas‐solid state, and chlorine was used as radical initiator as well as terminate agent. The effect of influence factors on the structure of the functionalized PP was investigated, and it was determined by levels of grafted GMA moieties. The results showed that PP modified with GMA could obtain higher grafting level. Crystallinity and mechanical properties of the functionalized PP were also investigated. For the purpose of researching the reactivity of epoxy groups located at the grafted side chains, trichloroacetic acid and hydroxyl‐terminated butadiene–acrylonitrile rubber (HTBN) were used as models to explore the ring open reaction of the epoxy groups of the functionalized PP. The structure and property of the modified PP that has undergone post‐ring open reaction was characterized by FTIR, dynamic property analysis. The results indicated that epoxy groups of the graft side chains have successfully undergone ring open reaction in the presence of carbonyl and hydroxyl groups. Additionally, the compatibilization of PP with HTBN is enhanced after PP was modified by GMA. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Preirradiation‐induced emulsion graft polymerization of glycidyl methacrylate onto poly(vinylidene fluoride) powder

An epoxy‐group‐containing monomer, glycidyl methacrylate (GMA), was grafted onto poly(vinylidene fluoride) powder via preirradiation‐induced emulsion graft polymerization. The existence of graft chains was proven by chemical structure characterization with Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy analysis. The degree of grafting was calculated by means of fluorine content analysis. A kinetic study indicated that, with the emulsion graft polymerization system, the GMA conversion rate was high, exceeding 80%. The variation in the molecular weight of the grafted polymer was measured by gel permeation chromatography, and its crystallinity was investigated with differential scanning calorimetry. The epoxy groups in graft chains were found to be suitable for further chemical modification. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Improved synthesis of a branched poly(ethylene imine)‐modified cellulose‐based adsorbent for removal and recovery of Cu(II) from aqueous solution

This study focuses on an improved synthesis of a branched poly (ethylene imine) (PEI)‐modified cellulose‐based adsorbent (Cell‐g‐PGMA‐PEI). We aim to improve the adsorbent capacity by reducing side reaction of epoxide ring opening during graft copolymerization of glycidyl methacrylate (GMA) onto cellulose which increases the content of epoxy groups, anchors to immobilize branched PEI moieties. FTIR spectra provided the evidence of successful graft copolymerization of GMA onto cellulose initiated by benzoyl peroxide (BPO) and modification with PEI. The amount of epoxy groups of Cell‐g‐PGMA was 4.35 mmol g^?1 by epoxy titration. Subsequently, the adsorption behavior of Cu(II) on cell‐g‐PGMA‐PEI in aqueous solution has been investigated. The data from the adsorption kinetic experiments agreed well with pseudo‐second‐order model. The adsorption isotherms can be interpreted by the Langmuir model with the maximum adsorption capacity of 102 mg g^?1 which was largely improved compared with the similar adsorbent reported. The dynamic adsorption capacity obtained from the column tests was 119 mg g^?1 and the adsorbent could be regenerated by HCl of 0.1 mol L^?1. Results indicate that the novel pathway for the synthesis of Cell‐g‐PGMA‐PEI exhibits significant potential to improve the performance of adsorbents in removal and recovery of Cu(II) from aqueous solution. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Atmospheric plasma‐aided biocidal finishes for nonwoven polypropylene fabrics. I. Synthesis and characterization

Novel biocidal fabrics were synthesized by the graft copolymerization of glycidyl methacrylate (GMA) onto plasma‐treated nonwoven polypropylene (PP) to produce PP/GMA grafts. Atmospheric oxygenated helium plasma was used to enhance the PP fabrics' initiation before GMA grafting. The grafted PP/GMA epoxide group was reacted with β‐cyclodextrin, monochlorotrizynyl‐β‐cyclodextrins, or a quaternary ammonium chitosan derivative [N‐(2 hydroxy propyl) 3‐trimethylammonium chitosan chloride]. Some interesting biocidal agents were complexed into the cyclodextrin (CD) cavity of PP/GMA/CD grafted fabrics. Fourier transform infrared spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and optical and scanning electron microscopies were used to characterize the grafted complexed fabrics. These synthesized biocidal fabrics proved to be antistatic, antimicrobial, and insect‐repelling (see part II of this study). © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1900–1910, 2007     

Studies on preparation of PGMA/Al2O3 and its effect on impact strength of epoxy resin

In this article, two kinds of methods for grafting polyglycidyl methacrylate (PGMA) onto Al₂O₃ surface by the radical polymerization initiated by peroxide groups and double bond groups, respectively, were investigated. In the first method, peroxide groups, as initiators, were immobilized onto the Al₂O₃ surface. Then, GMA was polymerized on Al₂O₃ under the radicals decomposed by peroxide groups, and PGMA was grafted onto Al₂O₃. But in the second method, 3‐methacryloylpropyl trimethoxysilane was chemically bonded onto the Al₂O₃ surfaces firstly to introduce double bonds. Secondly, the copolymerizations between the immobilized double bonds and the monomer GMA were performed, homopolymerizations of GMA followed, and finally PGMA was grafted to the Al₂O₃ surfaces. The effects of grafting methods on grafting degree were examined mainly. At the same time, the effects of different grafting conditions on the grafting degree were researched. Furthermore, the effect of the grafted particles PGMA/Al₂O₃ on impact strength of the epoxy composites was studied. It was found that the grafting degree achieved by the first method was much higher than that by the second, and the grafting degree can reach about 54%. Moreover, the impact strength of epoxy composites containing PGMA/Al₂O₃ particles were improved largely, and which increased with the grafting degree. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Surface modification of UHMWPE fibers by ozone treatment and UV grafting for adhesion improvement

In this study, the surface of ultra-high-molecular-weight-polyethylene (UHMWPE) fibers was modified by ozone pretreatment, followed by ultraviolet (UV) grafting, to enhance the interfacial properties of UHMWPE fibers/rubber composites. The fibers were first pretreated by ozone to introduce oxygen-functional groups. The graft polymerization of glycidyl methacrylate (GMA) onto the ozone-treated fibers was implemented by UV irradiation. The effects of time and GMA concentration on the grafting efficiency were investigated. The modified fibers were characterized by X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy dispersive spectrometry (EDS). The XPS and FTIR results revealed that GMA was successfully grafted onto the fibers with epoxy groups. SEM images confirmed that a continuous layer of poly-(GMA) (PGMA) was grafted onto the fibers. The interfacial adhesion force of UHMWPE fibers with rubber matrix was characterized by H pullout testing, which showed that the maximum force the fibers/rubber composites increased by 79% over that of the untreated fibers.     

PGMA/(Al)_2O_3制备及其对环氧树脂体系性能的影响

将带有环氧基的功能性单体甲基丙烯酸缩水甘油酯(GMA)接枝聚合在微米级氧化铝颗粒表面,制备了接枝微粒PGMA/(Al)_2O_3。考察了各种因素对接枝率的影响;利用红外光谱、扫描电镜表征了PGMA/(Al)_2O_3;并通过扫描电镜观察了PGMA/(Al)_2O_3在环氧树脂中的分散情况,初步研究了PGMA/(Al)_2O_3对环氧树脂体系的增强增韧性能。结果表明:表面引发自由基聚合反应可以成功制备复合粒子PGMA/(Al)_2O3,其接枝率随引发剂浓度和氧化铝与GMA质量比的增大先增大后减小;将PGMA/(Al)_2O_3填充到环氧密封材料中后,氧化铝颗粒在环氧树脂中分散良好,其复合材料的韧性明显高于未改性Al2O3填充的复合材料。     

PGMA／Al2O3填充环氧树脂灌封材料性能的研究

采用“Grafting from”的方法,制备了接枝微粒聚甲基丙烯酸缩水甘油酯／Al2O3（PGMA／Al2O3）。研究了PGMA/Al2O3及固化剂用量对环氧灌封材料的性能影响。利用扫描电镜观察了PGMA/Al2O3填充的环氧灌封材料的冲击断面的形貌。结果表明,对氧化铝粒子进行接枝改性后,复合粒子在环氧树脂灌封中得到良好的分散、增韧效果明显优于未改性的Al2O3,且在用量较少时就可明显提高环氧灌封材料的冲击强度。     

Preparation of silver-ion-loaded nonwoven fabric by radiation-induced graft polymerization

Sulfonic acid (SO₃H) groups were appended to three nonwoven fabrics made of polyethylene (PE), polypropylene (PP), and a hybrid of PP and PE by radiation-induced graft polymerization of glycidyl methacrylate (GMA) and subsequent ring-opening with sodium sulfite. Silver ion was loaded onto the resultant SO₃H-type cation-exchange nonwoven fabric at a density of 2.0 mmol g⁻¹, where the molar ratio of Ag ions to SO₃H groups was unity.     

Reactive grafting of glycidyl methacrylate onto polypropylene

This work explored the melt‐phase grafting of glycidyl methacrylate (GMA) onto polypropylene on a closely intermeshing corotating twin‐screw extruder (16‐mm screws, 40 : 1 length/diameter ratio). The modification of the base polypropylene to produce GMA‐grafted polypropylene was achieved via peroxide‐induced hydrogen abstraction from the polypropylene followed by the grafting of the GMA monomer or by the grafting of styrene followed by copolymerization with the GMA. In this study, both the position and order of the reactant addition were investigated as a route to improving graft yields and reducing side reactions (degradation). For the peroxide–GMA system, adding GMA to the melt before the peroxide resulted in significant improvements in the graft levels because of the improved dispersion of GMA in the melt. The addition of a comonomer (styrene) was explored as a second route to improving the graft yield. Although the addition of the comonomer led to a considerable rise in the level of grafted GMA, altering the order of the reactant addition was not found to contribute to an increase in the grafted GMA levels. However, variable levels of grafted styrene were achieved, and this may play an important role in the development of grafted polymers to suit specific needs. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Preparation of polymer‐supported polyethylene glycol and phase‐transfer catalytic activity in benzoate synthesis

The crosslinked polymeric microspheres (GMA/MMA) of glycyl methacrylate (GMA) and methyl methacrylate (MMA) were prepared by suspension polymerization. Polyethylene glycol (PEG) was grafted on GMA/MMA microsphers via the ring‐opening reaction of the epoxy groups on the surfaces of GMA/MMA microspheres, forming a polymer‐supported triphase catalyst, PEG‐GMA/MMA. The Phase‐transfer catalytic activity of PEG‐GMA/MMA microspheres was evaluated using the esterification reaction of n‐chlorobutane in organic phase and benzoic acid in water phase as a model system. The effects of various factors on the phase transfer catalysis reaction of liquid–solid–liquid were investigated. The experimental results show that the PEG‐GMA/MMA microspheres are an effective and stable triphase catalyst for the esterification reaction carried out between oil phase and water phase. The polarity of the organic solvent, the ratio of oil phase volume to water phase volume and the density of the grafted PEG on PEG‐GMA/MMA microspheres affect the reaction rate greatly. For this investigated system, the solvent with high polarity is appropriate, an adequate volume ratio of oil phase to water phase is 2:1, and the optimal PEG density on the polymeric microspheres is 15 g/100 g. Triphase catalysts offer many advantages associated with heterogeneous catalysts such as easy separation from the reaction mixture and reusability. The activity of PEG‐GMA/MMA microspheres is not nearly decreased after reusing of 10 recycles. © 2009 American Institute of Chemical Engineers AIChE J, 2010     

Microstructure and sulfonation of dual monomer-grafted polypropylene nonwoven fabrics

The sulfonation of styrenic polymers often needs harsh reaction conditions, such as concentrated sulfuric acid and elevated temperature. The awkward situation is handled by grafting copolymerization of polar and nonpolar monomers, and essentially the surface wettability between sulfonating agent and matrix polymer is circumvented in the study. Two pairs of dual monomers, glycidyl methacrylate (GMA)-acrylic acid (AA), styrene (St)-acrylic acid (AA), were grafted onto polypropylene nonwoven fabrics (PP) using thermal polymerization, and the resulted fabrics were further sulfonated using sodium sulfite and sulfuric acid, respectively. The microstructure of the modified fabrics was characterized by infrared spectroscopy and scanning electron microscopy. The ion exchange property was verified by copper (II) removal from aqueous solution, and its reutilization was carried out in electrochemical desorption process. The results show that hydrophilic and active monomer AA speeds grafting and sulfonation, but overload of AA will deteriorate copolymerization of GMA, and switch copolymerization chain component due to acylation with benzene ring. Although interfacial compatilizer promotes dual grafting, its overdosing may intensify microphase segregation of the grafting polymers owing to emulsification. The resultant granular polymers will be drained off during functionalization and reutilization processes. The ion exchange fabrics can be applied for treatment of metal ion wastewaters with unique electrochemical desorption feature. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48300.     

阴离子型双功能含环氧基团酶固定化载体的制备及其固定辣根过氧化酶

利用接枝聚合在微米级硅胶微粒表面的甲基丙烯酸缩水甘油酯(GMA)和对羟基苯磺酸钠(SHBS)发生环氧基团的部分开环反应,制得阴离子型双功能复合载体SHBS-PGMA/SiO2,研究了辣根过氧化酶(HRP)与载体SHBS-PGMA/SiO2间的静电相互作用在共价固定HRP过程中的作用及其机理. 结果表明,在较大的pH值范围内,复合载体SHBS-PGMA/SiO2表面携带高密度负电荷,pH=6.0时HRP分子荷正电,酶蛋白分子与载体间会产生强静电相互作用,显著促进HRP的固定化;当载体表面SHBS的键合率约为18%时,静电相互作用对固酶的促进作用最强,固定化酶的偶联率和比活力最高. 离子强度对酶的固定化也有很大影响,加入NaCl对载体与酶蛋白之间的静电相互作用力产生屏蔽作用,增大NaCl浓度可使固定化酶的偶联率和比活力降低.