Synthesis and photopolymerization of acrylic acrylate copolymers

Acrylate‐functionalized copolymers were synthesized by the modification of poly(butyl acrylate‐co‐glycidyl methacrylate) (BA/GMA) and poly(butyl acrylate‐co‐methyl methacrylate‐co‐glycidyl methacrylate). ¹³C‐NMR analyses showed that no glycidyl methacrylate block longer than three monomer units was formed in the BA/GMA copolymer if the glycidyl methacrylate concentration was kept below 20 mol %. We chemically modified the copolymers by reacting the epoxy group with acrylic acid to yield polymers with various glass‐transition temperatures and functionalities. We studied the crosslinking reactions of these copolymers by differential scanning calorimetry to point out the effect of chain functionality on double‐bond reactivity. Films formed from acrylic acrylate copolymer precursors were finally cured under ultraviolet radiation. Network heterogeneities such as pendant chains and highly crosslinked microgel‐like regions greatly influenced the network structure and, therefore, its viscoelastic properties. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 753–763, 2002     

Synthesis of new polyesters with methacrylate pendant groups

Summary A catalytic process for synthesis of new polyesters with methacrylate pendant groups is presented. Thus, zinc succinate catalyzed reaction of succinic anhydride with glycidyl methacrylate (GMA) in dimethoxyethane gives linear oligoesters with low molecular weights (1380-2400 Da). The polyester formation takes place via simultaneous ring opening of the cyclic anhydride and oxirane units. GMA component can be partially replaced with cyclohexeneoxide to obtain polyesters with methacrylate pendant groups in various percentages. Nearly colorless waxy polymers are obtained in excellent yields (69–97%) within 48–60 h. at 90 °C. In the study structure of the polymers have been elucidated by conventional spectroscopic techniques and photo-crosslinking of ability of their thin films have been tested by monitoring intensity of methacrylate double bonds, using IR-spectrometry methodology.     

Sulfonation of (glycidyl methacrylate) chains grafted onto nonwoven polypropylene fabric

Sulfonation of polyglycidyl methacrylate (PGMA) chains grafted onto nonwoven polypropylene fabric is investigated in detail. Sulfonation reaction consists in implantation of sulfonate groups via epoxy ring‐opening of PGMA chains grafted onto nonwoven polypropylene fabric by reaction between the GMA‐grafted sample and sodium hydrogensulfite in water–dimethylformamide solution. On the basis of analyses of IR spectra of the appropriate samples and data of backward titration, two simultaneous processes are demonstrated to take place during the sulfonation reaction. These processes are the implantation of sulfonate groups via opening of the GMA epoxy rings and hydrolysis of the GMA epoxy rings with α‐glycol groups formation. The main peculiarities of the sulfonation reaction in depending on the GMA grafting degree are reported. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

Copolymerizations of macromonomer prepared by addition-fragmentation chain transfer polymerization of methyl acrylate trimer

Summary An oligomer of the methyl acrylate unsaturated trimer bearing 2-carbomethoxy-2-propenyl ω-end group (M _n = 1300, M _w/M _n = 1.7, and functionality > 0.7) was copolymerized as a macromonomer (0.02 mol/L) with styrene (1.0 mol/L) in benzene at 60 °C. The amounts of monomer and macromonomer in the feed simultaneously decreased with increasing time to indicate copolymer formation, and the macromonomer was found to be as reactive as styrene toward poly(styrene) radicals. The M _ns of the copolymers were 13900–22000 depending on conversion. No resonance due to the unsaturated <ω-end group bound to the poly(styrene) chain was detected by ¹H-NMR spectroscopy, indicating that no fragmentation of adduct radical of the end group to expel the poly(methyl acrylate trimer) radical. Polymerization of ethyl methacrylate (1.0 mol/L) in the presence of the macromonomer (0.02 mol/L) resulted in a mixture of the unreacted macromonomer and homopolymer of ethyl methacrylate. No end group bound to the poly(ethyl methacrylate) was detected by ¹H-NMR spectroscopy, excluding the possibility of addition fragmentation chain transfer to the macromonomer to expel an oligomer radical of the methyl acrylate trimer. Addition of the poly(methacrylate) radical to the macromonomer is extremely slow under the present conditions of copolymerization. Received: 27 March 2003/Revised version: 30 April 2003/ Accepted: 30 April 2003 Correspondence to Bunichiro Yamada     

含氟环氧丙烯酸酯树脂固化动力学研究

采用甲基丙烯酸甲酯(MMA)、甲基丙烯酸缩水甘油酯(GMA)、丙烯酸六氟丁酯(F6BA),通过溶液聚合法制备了含氟环氧丙烯酸酯树脂P(MMA/GMA/F6BA)。采用DSC研究了以己二酸为固化剂的固化反应,确定固化反应动力学方程和固化反应级数;采用FTIR跟踪固化反应过程,确定固化反应时间。     

Effects of glycidyl methacrylate content and addition sequence on the acrylic latexes with carboxyl groups

Acrylic latexes with epoxy and carboxyl groups have been synthesized via a two-stage emulsion polymerization process. Different contents of glycidyl methacrylate (GMA) were introduced by three addition modes to copolymerize with methyl methacrylate, butyl acrylate, acrylic acid (AA) in the presence of K₂S₂O₈. To obtain stable latexes, NaHCO₃ was employed as a buffer to compensate for the acidity from the thermal dissociation of K₂S₂O₈, and triethylamine was used to neutralize the carboxyl acid from AA. The results showed that the stable latexes with core/shell structure were synthesized by this method, and higher GMA content or addition at earlier stage led to forming the latexes with higher content of coagulum and bigger sized particles. During the formation of films, the polymer epoxy groups underwent the crosslinking reaction with carboxyl acid. When the GMA content increased or GMA was introduced at a later stage, high crosslinking extent was formed in the films. As a result, the crosslinking provided the films with improved water resistance, chemical resistance, tensile strength, hardness, abrasion resistance, and thermal stability.     

Synthesis of poly(methylmethacrylate) macromonomers prepared by radical chain transfer reaction H NMR study of macromonomer end-groups

Summary The end-group analysis for both PMMA telomers having a carboxyl end-group and macromonomers derived from these telomers was carried out using ¹H NMR. Telomers were prepared by telomerization of methyl methacrylate (MMA) with thioglycolic acid (TGA) initiated with 2,2' azobis(isobutyronitrile) (AIBN) in acetonitrile at 70°C. Then, macromonomers were obtained by reaction of the telomer carboxylic acid end-group with glycidyl methacrylate (GMA) using a chromium salt as catalyst. From the ¹H NMR study, it was found that the telomer/macromonomer conversion results from two ways of epoxy addition (α and β), as observed in a model reaction between GMA and octanoic acid (OA). Received: 28 June 2000/Revised version: 6 November 2000/Accepted: 9 November 2000     

Surface modification of epoxy resin with fluorine-containing methacrylic ester copolymers

To improve oil and water repellency, fluorine-containing block copolymers, which were composed of methyl methacrylate (MMA), glycidyl methacrylate (GMA), and 1H, 1H, 2H, 2H-heptadecafluorodecyl acrylate (PFA), were blended with an epoxy resin. It was expected that a glycidyl group would mesh with the epoxy resin by primary bonding, and the low surface energy fluorocarbon segment would absorb and orient to the exterior to fluorinate the surface. X-ray photoelectron spectroscopy, contact angle, and peel strength of pressure-sensitive adhesives for modified epoxy resin surface were determined. The amount of fluorine obtained via angular-dependent ESCA investigation in the modified resin surfaces increased with the shallowing of the sampling depth. With increasing modifier content, the amount of fluorine in the modified resin surface layer increased, and the critical surface tension of modified resin surfaces and the peel strength of a silicone pressuresensitive adhesive affixed to the modified epoxy resin, decreased. A considerable amount of fluorine in the resin surface modified with GMA-containing block copolymers remained after Soxhlet extraction, whereas in the surface modified with copolymer without GMA, more fluorine was extracted. It was extracted. It was shown that these copolymers were good surface modifiers to improve oil and water repellency. © 1993 John Wiley & Sons, Inc.     

Glycidyl Methacrylate-Based Copolymers as Healing Agents of Waterborne Polyurethanes

Self-healing materials and self-healing mechanisms are two topics that have attracted huge scientific interest in recent decades. Macromolecular chemistry can provide appropriately tailored functional polymers with desired healing properties. Herein, we report the incorporation of glycidyl methacrylate-based (GMA) copolymers in waterborne polyurethanes (WPUs) and the study of their potential healing ability. Two types of copolymers were synthesized, namely the hydrophobic P(BA-co-GMAy) copolymers of GMA with n-butyl acrylate (BA) and the amphiphilic copolymers P(PEGMA-co-GMAy) of GMA with a poly(ethylene glycol) methyl ether methacrylate (PEGMA) macromonomer. We demonstrate that the blending of these types of copolymers with two WPUs leads to homogenous composites. While the addition of P(BA-co-GMAy) in the WPUs leads to amorphous materials, the addition of P(PEGMA-co-GMAy) copolymers leads to hybrid composite systems varying from amorphous to semi-crystalline, depending on copolymer or blend composition. The healing efficiency of these copolymers was explored upon application of two external triggers (addition of water or heating). Promising healing results were exhibited by the final composites when water was used as a healing trigger.     

New aqueous base developable photoresist for lithographic printing plates applications

Negative photoresists are materials that become insoluble in developing solution when exposed to optical radiation. This work describes the production of simple negative‐working resists, demonstrating aqueous development, for potential printing plate applications. The copolymers comprised glycidyl methacrylate (GMA) and acrylic acid (AA) via free‐radical solution polymerization in methyl ethyl ketone as a solvent using azobisisobutyronitrile as initiator at 60°C. Characterization of the copolymers prepared was carried out via IR, ¹H‐NMR, and thermal analysis techniques. The copolymers of GMA/AA were successfully prepared over a wide range of composition. It was found that the copolymer containing 15 mol % of AA unit in the feed was developed with NaOH on copper plate rather than zinc plate and crosslinked in the presence of photogenerated acid (PAG) caused by acid‐initiated ring‐opening polymerization of pendant epoxide groups. Exposure of the resist films to UV radiation at λ_max = 365 nm results in the generation of acid, and the subsequent baking process at 80°C for 1 min promotes the diffusion of the PAG, which initiates the cationic crosslinking of the epoxide rings. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Thiohydroxamic esters

Summary N-Hydroxypyridine-2-thione derivativesIa-c and N-hydroxy-4-methylthiazole-2(3H)-thione derivativesIIa-b act as chain transfer agents in free radical polymerizations of methyl methacrylate (C _x =0.6–4.3), styrene (C _x =0.32–3.9), methyl acrylate (C _x =3.1–20), and vinyl acetate (C _x =9.7–80) at 60°C. Some retardation occurs with vinyl acetate and methyl acrylate.Ib also has the property of initiating the polymerization of methyl methacrylate photochemically, whileIIb acts as a thermal initiator. The chain transfer constants ofIIb make it particularly suitable for regulating molecular weight in batch polymerizations of methyl methacrylate and styrene.     

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     

Molecular mass control in methacrylic copolymer latexes containing glycidyl methacrylate

Results are presented on the preparation and characterization of batch emulsion copolymers of butyl methacrylate and glycidyl methacrylate (GMA). The two main problems occurring during an emulsion copolymerization with GMA are partial hydrolysis of the epoxy groups and internal crosslinking of the latex particles formed. The influence of chain transfer agents (CTA) on the degree of crosslinking was investigated. Furthermore, the effect of reaction temperature and the addition of methacrylic acid on the sol/gel content of the polymer formed and on the rate of epoxy hydrolysis were investigated. It was found that lowering the reaction temperature did not increase the sol content; however, it significantly decreased the extent of hydrolysis. The addition of a CTA (especially CBr₄) increased the sol content of the polymer, and good control over the molecular mass was achieved. The addition of methacrylic acid showed that this monomer can be used without any complications with respect to the control of the sol content of the polymer formed. © 1996 John Wiley & Sons, Inc.     

Poly(methylphenylphosphazene)–Graft–Poly(methyl Methacrylate) Copolymers Via Atom Transfer Radical Polymerization

Atom transfer radical polymerization (ATRP) was used to graft poly(methyl methacrylate), PMMA, onto poly(methylphenylphosphazene), [(Me)(Ph)PN] _n , PMPP. A two-step process was used to convert a portion of the methyl substituents on [(Me)(Ph)PN] _n to –CH₂C(CH₃)₂OH groups and then to bromoalkyl groups, –CH₂C(CH₃)₂OC(=O)C(CH₃)₂Br, the latter of which served as initiation sites for ATRP of methyl methacrylate (MMA) in the presence of CuCl/bipyridine. Variations in the length of the grafted chains were investigated and the graft copolymers were compared to the parent polymer and blends of similar composition. The new bromoalkyl derivatives of [(Me)(Ph)PN] _n and the PMPP–graft–PMMA copolymers were characterized by elemental analysis, ¹H and ³¹P NMR spectroscopy, size exclusion chromatography (SEC), and differential scanning calorimetry (DSC). We dedicate this paper to Professor Harry R. Allcock for consistently maintaining the highest standards in his creative, pioneering work in inorganic rings and polymers.     

Copolymerization of 4-cyanophenyl acrylate with methyl methacrylate: synthesis, characterization and determination of monomer reactivity ratios

A novel acrylic monomer, 4-cyanophenyl acrylate (CPA) was synthesized by reacting 4-cyanophenol dissolved in methyl ethyl ketone with acryloyl chloride in the presence of triethylamine as a catalyst. Copolymers of CPA with methyl methacrylate (MMA) at different composition was prepared by free radical solution polymerization at 70 ± 1 °C using benzoyl peroxide as an initiator. The copolymers were characterized by FT-IR, ¹H-NMR and ¹³C-NMR spectroscopic techniques. The solubility tests were checked in various polar and non polar solvents. The molecular weight and polydispersity indices of the copolymers were estimated by using gel permeation chromatography. The glass transition temperature of the copolymers increases with increases MMA content. The thermal stability of the copolymer increases with increases in mole fraction of CPA content in the copolymer. The copolymer composition was determined by using ¹H-NMR spectra. The monomer reactivity ratios determined by the application of linearization methods such Fineman–Ross (r ₁ = 0.535, r ₂ = 0. 0.632), Kelen–Tudos (r ₁ = 0.422, r ₂ = 0.665) and extended Kelen–Tudos methods (r ₁ = 0.506, r ₂ = 0. 0.695).     

Core-shell particles designed for toughening the epoxy resins. II. Core-shell-particle-toughened epoxy resins

The diglycidyl ether of bisphenol A–m-phenylene diamine (DGEBA–MPDA) epoxy resin was toughened with various sizes and amounts of reactive core-shell particles (CSP) with butyl acrylate (BA) as a core and methyl methacrylate (MMA) copolymerized with various concentration of glycidyl methacrylate (GMA) as a shell. Ethylene glycol dimethacrylate (EGDMA) was used to crosslink either core or shell. Among the variables of incorporated CSP indicated above, the optimal design was to obtain the maximum plastic flow of epoxy matrix surrounding the cavitated CSP during the fracture test. It could be achieved by maximizing the content of GMA in a shell-crosslinked CSP, the particle size, and the content of CSP in the epoxy resin without causing the large-scale coagulations. The incorporation of reactive CSP could also accelerate the curing reaction of epoxy resins. Besides, it was able to increase the glass transition temperature of epoxy resins if the particle size ≤0.25 μm and the dispersion was globally uniform. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 70: 2313–2322, 1998     

Compatibilization and characterization of blends of styrene–maleic anhydride copolymer with modified polyethylenes

Potentially reactive blends of styrene–maleic anhydride (SMAH) with ethylene/methyl acrylate/glycidyl methacrylate (E‐MA‐GMA) and nonreactive blends of SMAH with ethylene/methyl acrylate (E‐MA) were produced in a Brabender batch mixer and in a corotating twin‐screw extruder. The products were characterized in terms of rheology, morphology, and mechanical properties to understand the reaction characteristics between anhydride/epoxy functional groups. Storage modulus, G′, loss modulus, G″ and complex viscosity, η* of the reactive blends were higher than those of nonreactive ones. At 25% E‐MA‐GMA content, maximum in η* was obtained for the reactive blends. The reactive blends showed finer morphology than the nonreactive ones at all concentrations studied. Mechanical characterization showed that reactive SMAH/E‐MA‐GMA blends had higher tensile strength, % strain at break, and tensile modulus than the nonreactive blends for all corresponding modified polyethylene contents. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 790–797, 2001     

Copolymerization of 5-vinyl-1,3-benzodioxole with n-butyl acrylate and methyl methacrylate

Summary Copolymers of 5-vinyl-1, 3-benzodioxole (VBD) with n-butyl acrylate and methyl methacrylate were synthesized. The copolymers were synthesized according to a designed experiment methodology and reactivity ratios were estimated using a nonlinear least squares error-in-variables procedure. The values of r₁ and r₂ obtained show that VBD is slightly less reactive than styrene in similar copolymerization reactions.     

Synthesis of poly(epichlorohydrin‐g‐methyl methacrylate) and poly(epichlorohydrin‐g‐styrene) graft copolymers by a combination of cationic and photopolymerization methods

Poly(epichlorohydrin‐g‐styrene) and poly (epichlorohydrin‐g‐methyl methacrylate) graft copolymers were synthesized by a combination of cationic and photoinitiated free‐radical polymerization. For this purpose, first, epichlorohydrin was polymerized with tetrafluoroboric acid (HBF₄) via a cationic ring‐opening mechanism, and, then, polyepichlorohydrin (PECH) was reacted ethyl‐hydroxymethyl dithio sodium carbamate to obtain a macrophotoinitiator. PECH, possessing photolabile thiuram disulfide groups, was used in the photoinduced polymerization of styrene or methyl methacrylate to yield the graft copolymers. The graft copolymers were characterized by ¹H‐NMR spectroscopy, differential scanning calorimetry, and gel permeation chromatography. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

The copolymerization of 2-vinylfuran with methyl methacrylate andn-butyl acrylate

Summary 2-Vinylfuran (2VF) was copolymerized with methyl methacrylate and n-butyl acrylate according to an experimental design scheme. The results were analyzed with a nonlinear error-in-variables method. The values obtained for the reactivity ratios using this approach were much different than reactivity ratios obtained from conventional copolymerization experiments. The r₁ and r₂ values obtained in the present case indicate that 2VF has approximately the same reactivity as methyl methacrylate, but is much more reactive than n-butyl acrylate.