Poly(N‐hydroxyethyl acrylamide)‐b‐polystyrene by combination of ATRP and aminolysis processes

Block copolymers of very hydrophilic poly(N‐hydroxyethyl acrylamide) (PHEAA) with polystyrene (PS) were successfully synthesized by sequential atom transfer radical polymerization of ethyl acrylate (EA) and styrene monomers and subsequent aminolysis of the acrylic block with ethanolamine. Quantitative aminolysis of poly(ethyl acrylate) (PEA) block yielded poly(N‐hydroxyethyl acrylamide)‐b‐polystyrene in well‐defined structures, as evidenced by Fourier transform infrared spectroscopy (FTIR) and ¹H‐NMR spectroscopy techniques. Three copolymers with constant chain length of PHEAA (degree of polymerization: 80) and PS blocks with 21, 74, and 121 repeating units were prepared by this method. Among those, the block copolymer with 21 styrene repeating units showed excellent micellation behavior in water without phase inversion below 100°C, as inferred from dynamical light scattering, environmental scanning electron microscopy, and fluorescence measurements. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Preparation and characterization of polyaniline N‐grafted with poly(ethyl acrylate) synthesized via atom transfer radical polymerization

Polyaniline (PANI) N‐grafted with poly(ethyl acrylate) (PEA) was synthesized by the grafting of bromo‐terminated poly (ethyl acrylate) (PEA‐Br) onto the leucoemeraldine form of PANI. PEA‐Br was synthesized by the atom transfer radical polymerization of ethyl acrylate in the presence of methyl‐2‐bromopropionate and copper(I) chloride/bipyridine as the initiator and catalyst systems, respectively. The leucoemeraldine form of PANI was deprotonated by butyl lithium and then reacted with PEA‐Br to prepare PEA‐g‐PANI graft copolymers containing different amounts of PEA via an N‐grafting reaction. The graft copolymers were characterized by Fourier transform infrared spectroscopy, elemental analysis, and thermogravimetric analysis. Solubility testing showed that the solubility of PANI in chloroform was increased by the grafting of PEA onto PANI. The morphology of the PEA‐g‐PANI graft copolymer films was observed by scanning electron microscopy to be homogeneous. The electrical conductivity of the graft copolymers was measured by the four‐probe method. The results show that the conductivity of the PANI decreased significantly with increasing grafting density of PEA onto the PANI backbone up to 7 wt % and then remained almost constant with further increases in the grafting percentage of PEA. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

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.     

Swelling of High Oil-Absorptive Network Based on 1-Octene and Isodecyl Acrylate Copolymers

Crosslinked 1-octene-isodecyl acrylate copolymers were synthesized and evaluated for oil-absorbency application. The copolymer was crosslinked at different concentrations of ethylene glycol diacrylate (EGDA) and ethylene glycol dimethacrylate (EGDMA) crosslinkers via catalytic initiation or by electron-beam irradiation at dose rate 80 kGy. The concentration of both crosslinkers was varied from 0.5% to 2%. The effect of crosslinking conditions, such as crosslinker concentration, method of polymerization and monomers concentration on conversion and gel fraction was examined through an oil-absorption test using petroleum crude oil. It was found that, the oil absorbency was influenced mainly by the degree of crosslinking and the hydrophobicity of the copolymer units. The final equilibrium oil content, volume fraction of polymer and swelling capacity were determined at 298 K. The effective crosslinking density V_e, the average molecular weight between the crosslinks M_c and the polymer-toluene interaction parameter were determined from stress–strain measurements. The crosslinking efficiencies of EGDA and EGDMA towards copolymers were determined.     

Block, blocky gradient and random copolymers of 2-ethylhexyl acrylate and acrylic acid by atom transfer radical polymerization

The controlled synthesis of low-T_g poly(2-ethylhexyl acrylate) (P2EHA) and derived random, block and blocky gradient copolymers via atom transfer radical polymerization (ATRP) is described. After optimizing the reaction conditions for the homopolymerization of 2EHA via ATRP, the synthesis of a variety of copolymers with poly(t-butyl acrylate) (PtBuA) was investigated. First, AB-block copolymers were targeted, starting from P2EHA and PtBuA as macroinitiators. Second, random copolymers of tBuA and 2EHA with different monomer ratios were synthesized. Finally, the synthesis of “blocky” gradient copolymers via a one-pot procedure was investigated, starting with the homopolymerization of tBuA, followed by the addition of 2EHA. The hydrolysis of the PtBuA-segments to poly(acrylic acid) (PAA), which was carried out with methanesulfonic acid, resulted in block, blocky gradient and random copolymers consisting of PAA and P2EHA. Solubility testing of the copolymers in slightly basic water (pH ∼ 9) demonstrated that the gradient structure significantly enhances solubility compared to the block copolymer structures with equal composition. The polymers have been characterized by MALDI-TOF MS, GPC and ¹H NMR.     

Synthesis of poly(octadecyl acrylate‐b‐styrene‐b‐octadecyl acrylate) triblock copolymer by atom transfer radical polymerization

The synthesis of triblock copolymer poly(octadecyl acrylate‐b‐styrene‐b‐octadecyl acrylate), using atom transfer radical polymerization (ATRP), is reported. The copolymers were prepared in two steps. First, polystyrene was synthesized by ATRP using α,α′‐dichloro‐p‐xylene/CuBr/bpy as the initiating system; Second, polystyrene was further used as macroinitiator for the ATRP of octadecyl acrylate to prepare ABA triblock copolymers in the presence of FeCl₂·4H₂O/PPh₃ in toluene. Polymers with controlled molecular weight (M_n = 17,000–23,400) and low polydispersity index value (1.33–1.44) were obtained. The relationship between molecular weight versus conversion showed a straight line. The effect of reaction temperature on polymerization was also investigated, showing a faster polymerization rate under higher temperature. The copolymers were characterized by FTIR, ¹H‐NMR, DSC, and GPC and the crystallization behavior of the copolymers was also studied. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1539–1545, 2004     

Free Radical Copolymerization of Novel Methacrylates with Acrylonitrile and Determination of Monomer Reactivity Ratios

p-methoxyphenoxy and p-chlorophenoxy group containing methacrylate based monomer 2-(p-methoxyphenoxy)-2-oxo-ethyl methacrylate (pMPOEMA) and 2-(p-chlorophenoxy)-2-oxo-ethyl methacrylate (p-ClPOEMA) were synthesized by reacting p-methoxyphenyl chloroacetate (pMPClAcO) and p-chlorophenyl chloroacetate (pClPClAcO) with sodium methacrylate in acetonitrile respectively. (pMPClAcO) and (pClPClAcO) were prepared by reacting p-methoxyphenol and p-chlorophenol dissolved in benzene with chloroacetylchloride. The free-radical-initiated copolymerization of (pMPOEMA) and (pClPOEMA) with acrylonitrile (AN) were carried out in 1,4-dioxane solution at 65 ^○C using 2,2′-azobisisobutyronitrile (AIBN) as an initiator with different monomer-to-monomer ratios in the feed. The monomers and copolymers were characterized by FTIR, ¹H- and ¹³C-NMR spectral studies. The copolymer compositions were evaluated by nitrogen content in polymers. The reactivity ratios of the monomers were determined by the application of Fineman–Ross and Kelen–Tüdös methods. The analysis of reactivity ratios revealed that pMPOEMA and pClPOEMA are more reactive than AN, and copolymers formed are statistically in nature. The molecular weights ( and ) and polydispersity index of the polymers were determined using gel permation chromagtography. Thermogravimetric analysis of the polymers reveal that the thermal stability of the copolymers increases with an increase in the mole fraction of AN in the copolymers. Glass transition temperatures of the copolymers were found to decrease with an increase in the mole fraction of AN in the copolymers.     

Copolymerization of 2-(4-tert-butylphenoxy)-2-oxo-ethyl Methacrylate with Methyl Methacrylate and Styrene: Synthesis, Characterization, and Monomer Reactivity Ratios

A tertierbutylphenoxy group containing methacrylate based monomer 2-(4-tert-butylphenoxy)-2-oxo-ethyl methacrylate (TBPOEMA) was synthesized by reacting 4-tertierbutylphenyl chloroacetate (TBPClAcO) with sodium methacrylate in acetonitrile. TBPClAcO was prepared by reacting tertierbutylphenol dissolved in benzene with chloroacetylchloride. The free-radical-initiated copolymerization of TBPOEMA, with methyl methacrylate (MMA) and styrene (ST) was carried out in dimethylsulphoxide (DMSO) solution at 65°C using 2,2-azobisisobutyronitrile (AIBN) as an initiator with different monomer-to-monomer ratios in the feed. The monomer TBPOEMA and copolymers were characterized by FTIR, ¹H- and ¹³C-NMR spectral studies. The copolymer composition obtained from the ¹H-NMR spectra led to the determination of reactivity ratios. The reactivity ratios of the monomers were determined by the application of Finemann–Ross and Kelen–Tüdös linear methods and the Behnken nonlinear least-squares method. The analysis of reactivity ratios revealed that MMA and ST are more reactive than TBPOEMA, and copolymers formed are statistical in nature. The molecular weights _w and _n) and polydispersity index of the polymers were determined using gel permation chromagtography. Thermogravimetric analysis of the polymers reveal that the thermal stability of the copolymers increases with an increase in the mole fraction of TBPOEMA in the copolymers. Glass transition temperatures of the copolymers were found to decrease with an increase in the mole fraction of TBPOEMA in the copolymers. The apparent thermal decomposition activation energies (E _d) were calculated by Ozawa method using the SETARAM Labsys TGA thermobalance.     

Study of the Copolymerization Parameters of 2-Thiozyl Methacrylamide with Different Alkyl Acrylates

2-thiozyl methacrylamide (TMA) was synthesized by the reaction of 2-aminothiazole with either methacryloyl chloride or methacrylic acid in the presence of triethylamine and N, N′-dicyclohexylcarbodiimide, respectively. Binary copolymerization reactions of the prepared monomer with methyl acrylate (MA), ethyl acrylate (EA), n-butyl acrylate (BA) and tert-butylacrylate (t.BA) were performed in dimethylformamide at 65^○C using 1 mol% azobisisobutyronitrile (AIBN) as initiator. The structure of the 2-thiozyl methacrylamide monomer and the prepared copolymers was investigated by IR and ¹H NMR spectroscopy. The copolymer compositions were determined from sulphur analysis. Copolymerization parameters for each system were calculated by the Finemen–Ross and Kelen–Tüdös methods. The monomer reactivity ratios for the systems TMA-MA, TMA-EA, TMA-BA, and TMA-tBA were found to be r₁=0.128, r₂=0.740; r₁=0.235, r₂=0.420; r₁=0.420, r₂=0.330 and r₁=1.690, r₂=0.027, respectively. The reactivities of acrylic esters decrease as the alkyl group become bulkier. The average Q and e values for TMA were calculated from the monomer reactivity ratios determined in the present and previous studies.     

In-situ polymerization of n-butyl acrylate in poly(vinyl chloride)

The in situ polymerization of n-butyl acrylate with poly(vinyl chloride) has been studied. Butyl acrylate was polymerized using a peroxydicarbonate initiator and a thiol chain transfer agent in the presence of poly (vinyl chloride) beads suspended in water. The products were examined, after pressing into sheets, for optical clarity and by dynamic mechanical analysis. It was found that if 10% butyl acrylate was peesent in the mixture homogeneous blends were formed but if 15% or more butyl acrylate was present two phase mixtures were formed. If homogeneous blends prepared as above were reswollen in butyl acrylate, and the latter then polymerized, homogeneous blends containing more poly(butyl acrylate) could be prepared. The interaction parameters between both poly(vinyl chloride' and poly(butyl acrylate) and butyl acrylate were estimated by inverse gas chromatography. Using these and an estimate of the polymer/polymer interaction parameter the three component phase diagram could be qualitatively explained.     

Why tanδ of poly (butyl acrylate) and poly (ethyl acrylate) with little double bonds are becoming asymmetric?

The little amount of internal double bonds were introduced in poly (butyl acrylate) (PBA) and poly (ethyl acrylate) (PEA) through copolymerizing with isoprene (IP). The tanδ of PBA-co-IP (BA-IP copolymer) and PEA-co-IP (EA-IP copolymer) exhibited an asymmetric double-peak structure with a shoulder at higher temperature side and a maximum at lower temperature side, while the tanδ of PBA and PEA generally displayed single-peak structure. The relaxation spectra showed motion units whose relaxation time were larger than 100 s appeared; so the shoulders were preliminarily determined as the slower processes. The chain-ring assumption was used to analyze this phenomenon. The single bonds that are adjunct to internal double bonds were thought as the “rings” and segments that locate between two neighboring single bonds were thought as the “chains”. Because “rings” single bonds had larger rotation ability than general single bonds, the motions of “chains” between two neighboring “rings” would be improved. Thus, PBA-co-IP and PEA-co-IP displayed asymmetric tanδ curves in mechanical spectra.     

Syntheses,antitumour activities and antiangiogenesis of 1,2,3‐tris(ethoxycarbonyl)‐2‐propyl acrylate and its polymers

A new monomer, 1,2,3‐tris(ethoxycarbonyl)‐2‐propyl acrylate (TPA), was synthesized by reaction of acryloyl chloride and triethyl citrate. The homopolymer of TPA and its copolymers with acrylic acid (AA), vinyl acetate (VAc) and maleic anhydride (MAH) were prepared by polymerization using lauroyl peroxide (LPO) at 70 °C for 24 h. The structures of TPA and its polymers were identified by FTIR, ¹H NMR, ¹³C NMR spectroscopies, and elemental analysis. The number average molecular weights and polydispersity indices of the synthesized polymers determined by GPC were in the range 4200–23 000 g mol^?1 and 1.1–2.1, respectively. The IC₅₀ values of the synthesized samples against cancer cell lines were greater than those of 5‐fluorouracil (5‐FU). The percentage inhibition values of SV40 DNA replication were 82.2 for TPA, 34.3 for poly (TPA), 81.9 for poly(TPA‐co‐AA), 82.0 for poly(TPA‐co‐VAc), 35.6 for poly(TPA‐co‐MAH) and 12.7 for 5‐FU. The inhibitions of SV40 DNA replication and antiangiogenesis for the synthesized TPA and its polymers are much greater than those of the control. © 2001 Society of Chemical Industry     

Kinetics of graft copolymerization of poly(hexanedioic acid ethylene glycol) and methyl acrylate initiated by potassium diperiodatocuprate(III)

A redox system, potassium diperiodatocuprate(III) [DPC]/poly(hexanedioic acid ethylene glycol) (PEA) system, was employed to initiate graft copolymers of methyl acrylate (MA) and PEA in alkaline medium. The results indicate that the equation of the polymerization rate (R_p) is as follows: R_p = k [MA]^1.62[Cu(III)]^0.69, and that the overall activation energy of graft polymerization is 42.5 kJ/mol. The total conversion at different conditions (concentration of reactants, temperature, concentration of the DPC, and reaction time) was also investigated. The infrared spectra proved that the graft copolymers were synthesized successfully. Some basic properties of the graft copolymer were studied by instrumental analyses, including thermogravimetry and scanning electron microscope. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2376–2381, 2007     

Silicone/polypropylene oxide-polyethylene oxide copolymer/clay composites (i) - curing behavior,intermolecular interaction and thermomechanical properties

The copolymerization of 2-(3-mesityl-3-methylcyclobutyl)-2-ketoethyl methacrylate monomer with acrylonitrile and styrene were carried out in 1,4-dioxane solution at 60^○C using AIBN as an initiator. The copolymers were characterized by Fourier transform infrared, ¹H-NMR, and ¹³C-NMR spectroscopic techniques. Thermal properties of the polymers were also studied by thermogravimetric analysis and differential scanning calorimetry. The copolymer compositions were determined by elemental analysis and ¹H-NMR technique. The monomer reactivity ratios were calculated by the application of conventional linearization methods as a result of Fineman–Ross and Kelen–Tüdös to less than 1 for both monomers.     

1,4-pentadien-3-one-1-p-hydroxyphenyl-5-p-phenyl Acrylate: Crosslinking Studies and Reactivity Ratios with Glycidyl Methacrylate

1,4-pentadien-3-one-1,5-bis(p-hydroxyphenyl) (PBHP) was synthesized by reacting p-hydroxybenzaldehyde and acetone in the presence of HCl gas. 1,4-pentadien-3-one-1-p-hydroxyphenyl-5-p-phenyl acrylate (HPA) was prepared by reacting PBHP with acryloyl chloride in ethyl methyl ketone (EMK) medium at 0°C. Copolymerization of different feed compositions of HPA with glycidyl methacrylate (GMA) was carried out using benzoyl peroxide (BPO) as initiator in EMK solvent under nitrogen atmosphere at 70±1°C. Polymers thus synthesized were characterized by IR and NMR (¹H/¹³C) spectroscopic techniques. Reactivity ratios of the monomers were calculated from the ¹H NMR data by applying linearization methods such as Fineman–Ross, Kelen–Tudos and extended Kelen–Tudos methods. Photocrosslinking property of the polymer samples was studied using the solvent method. Thermal stability of the polymers were measured using thermogravimetric analysis. Molecular weights (M _w and M _n) and polydispersity value of the polymer were determined using gel permeation chromatographic technique.     

Modification of poly(vinyl chloride) by IPN formation with poly(ethyl acrylate)

Semi‐1 and semi‐2 interpenetrating polymer networks (IPNs) of poly(vinyl chloride) (PVC) and in situ formed poly(ethyl acrylate) (PEA) have been synthesized using diallyl phthalate and ethylene glycol dimethacrylate as the crosslinkers of PVC and PEA, respectively. These two types of IPNs have been compared with respect to their physical, mechanical, and thermal properties and an endeavor has been made to find a correlation of these properties with the morphology generated in these systems. The semi‐1 IPNs displayed a decrease in their tensile strength and modulus while in contrast; the semi‐2 IPNs exhibited a marginal increase with increasing crosslinked PEA incorporation. The semi‐1 and semi‐2 IPNs containing 10 and 30 wt % of PEA displayed a two‐stage degradation typical of PVC in their thermogravimetric and DSC studies while confirming the increased stability of the samples with higher percentages of PEA. The softening characteristics as detected by the extent of penetration of the thermomechanical probe as has been detected by thermomechanical analysis are in conformity with their mechanicals. The biphasic cocontinuous systems as explicit from the morphological studies reveal fibrillar characteristics in both the systems. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Comparison of thermomechanical properties of statistical, gradient and block copolymers of isobornyl acrylate and n-butyl acrylate with various acrylate homopolymers

Well-defined statistical, gradient and block copolymers consisting of isobornyl acrylate (IBA) and n-butyl acrylate (nBA) were synthesized via atom transfer radical polymerization (ATRP). To investigate structure-property correlation, copolymers were prepared with systematically varied molecular weights and compositions. Thermomechanical properties of synthesized materials were analyzed via differential scanning calorimetry (DSC), dynamic mechanical analyses (DMA) and small-angle X-ray scattering (SAXS). Glass transition temperature (T_g) of the resulting statistical poly(isobornyl acrylate-co-n-butyl acrylate) (P(IBA-co-nBA)) copolymers was tuned by changing the monomer feed. This way, it was possible to generate materials which can mimic thermal behavior of several homopolymers, such as poly(t-butyl acrylate) (PtBA), poly(methyl acrylate) (PMA), poly(ethyl acrylate) (PEA) and poly(n-propyl acrylate) (PPA). Although statistical copolymers had the same thermal properties as their homopolymer equivalents, DMA measurements revealed that they are much softer materials. While statistical copolymers showed a single T_g, block copolymers showed two T_gs and DSC thermogram for the gradient copolymer indicated a single, but very broad, glass transition. The mechanical properties of block and gradient copolymers were compared to the statistical copolymers with the same IBA/nBA composition.     

Synthesis of IPN-related materials from solution of polyacrylates

IPN-related materials were synthesized from solution of two acrylate polymers having epoxide. From the dynamic mechanical spectroscopy, it was difficult to distinguish IPN or semi-IPN from mechanical blend in the case of PEMA/P2EHMA system. But some possibility of IPN phenomenon was observed. In the case of PEMA/PEA system, IPN synthesized from benzene-chloroform mixed solvent showed phase separation with the matrix of PEMA. IPN synthesized from xylene, however, showed phase separation with the matrix of PEA and the transition due to PEA shifted higher by 5°C than that of homo PEA. From the results, we concluded that PEMA/PEA system synthesized by xylene showed JPN phenomenon.     

Synthesis and characterization of poly(acrylate amic acid) and its application as negative‐tone photosensitive polyimides

The dianhydride monomer 3,3′,4,4′‐benzophenone tetracarboxylic acid dianhydride and two diamine monomers, 4,4′‐diamino‐3,3′‐biphenyldiol (HAB) and 2,4‐diaminophenol dihydrochloride (DAP), were used to synthesize a series of poly(hydroxyl amic acid). Further functionalization by grafting acrylate groups yields the corresponding poly(acrylate amic acid) that underwent a crosslinking reaction on exposure to UV‐light and was used as a negative‐tone photosensitive polyimide (PSPI). The analysis of chemical composition and molecular weight of these poly(amic acid)s determined by nuclear magnetic resonance (NMR) spectroscopy, Fourier transform infrared spectroscopy, and gel permeation chromatography revealed that the molecular weight of the poly(hydroxyl amic acid) increased with the molar content of HAB in the feedstock, because HAB exhibited higher polymerization reactivity than DAP. Moreover, the degree of grafting acrylate groups onto poly(hydroxyl amic acid) was determined by ¹H‐NMR spectroscopy. The photoresist was formulated by adding 2‐benzyl‐2‐N,N‐dimethylamino‐1‐(4‐morpholinophenyl) butanone (IRG369) and isopropylthioxanthone as a photoinitiator, tetra(ethylene glycol) diacrylate as a crosslinker, and tribromomethyl phenyl sulfone as a photosensitizer. The PSPI precursor exhibited a photosensitivity of 200 mJ/cm² and a contrast of 1.78. A pattern with a resolution of 10 μm was observed in an optical micrograph after thermal imidization at 300°C. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009