Synthesis and thermal self-crosslinking reaction of copolymers from 2,3-epoxypropyl methacrylate and p-substituted phenyl methacrylates

Copolymers of 2,3-expoxypropyl (glycidyl) methacrylate (GMA) with various phenyl methacrylates such as 4-nitrophenyl methacrylate (NPMA), 4-chlorophenyl methacrylate (CPMA), or phenyl methacrylate (PMA), and other monomers such as methyl methacrylate (MMA), ethyl acrylate (EA), or styrene (ST) were synthesized by radical copolymerization, and then thermal self-crosslinking reactions of the obtained copolymers were carried out using various catalysts such as quarternary ammonium salts, tert-amines, or the crown ether/potassium salt systems at 100–150°C. Although the copolymer of GMA–NPMA–MMA does not produce any gel products without catalyst upon heating at 110°C for 5 h, this copolymer gives gel products in 82% yield using 10 mol% of tetrabutylammonium bromide as a catalyst under the same conditions. The rate of gel production of the copolymer of NPMA is faster than those of copolymers of CPMA and PMA. The rate of the gel production of the copolymer of GMA–NPMA–EA is also faster than those of copolymers of MMA and ST. Furthermore, it was found that the rate of gel production of the copolymer was strongly affected by the kind of catalyst, the catalyst concentration, and the reaction temperature.     

Studies of reactions with polymers. III. Syntheses and properties of poly(vinyl alcohol) graft terpolymers

A condensation-coupling reaction through esterification is performed between the hydroxy groups of poly(vinyl alcohol) (PVA) and the anhydride groups of methyl methacrylate (MMA)-co-maleic anhydride (MA) copolymer to produce the PVA-g-MMA/MA graft terpolymer. The MMA-co-MA copolymer was obtained by copolymerization of MA and MMA in dimethyl sulfoxide by using azobisisobutyronitrile as initiator. The structure of reaction products was confirmed by infrared analysis, and the dependence of composition, viscosity, and yield of the graft terpolymer on the MA content in MMA-co-MA as well as the concentration of the reactants fed were investigated. Mechanical properties, water content, and gel content of the membranes of terpolymers were measured over a wide range of compositions. PVA-g-MMA/N-ethylol maleimide was also synthesized by reacting the residual anhydride groups on PVA-g-MMA/MA with ethanol amine, this reaction proceeds through the PVA-g-MMA/N-ethylol maleamic acid intermediate.     

Highly efficient block copolymerization of methyl and t-butyl methacrylates by an incomplete and slow initiation system

Summary Block copolymerization of methyl methacrylate (MMA) with t-butyl methacrylate (t-BMA) was carried out in toluene at-78°C with triphenylphosphine (Ph₃P)-triethylaluminum (Et₃Al) initiating system. Polymerization of MMA with Ph₃P-Et₃Al under the same conditions gave highly syndiotactic PMMA living anion with low initiator efficiency. Even though a large part of the initiator remained unreacted, polymerization of t-BMA with the living anion of PMMA gave block copolymer without formation of poly(t-BMA), since t-BMA alone could not be polymerized under the same conditions due to the inability of initiation with Ph₃P-Et₃Al.     

A Crosslinked Copolymer with N‐Bromosulfonamide Pendant Groups as Oxidant for Residual Sulfides in Alkaline Media

A redox copolymer, a macromolecular analogue of Bromamine T was prepared and developed as a solid phase oxidizing reagent for sulfides being in trace concentration in aqueous solutions. The resin was prepared starting from Amberlyst 15 by a four‐step transformation of the sulfonic groups to N‐bromosulfonamide. The product containing 3.30 meq active bromine/g showed strong oxidizing properties and was employed in batch as well as in flow processes for removal of sulfides from solutions by their transformation to sulfates. The starting solution contained 64.0 or 320.0 mg S^2–/dm³. The effects of various parameters on the reaction course have been studied (mole ratio of reagents, alkalinity of the reaction media, flow rate in the column processes). The solid phase oxidation carried out in a dynamic regime provided to drive the reaction to completion. Thus, sulfide free effluents (< 10 μg S^2–/dm³) were obtained in the column processes. The permissible flow rate, close to 10–12 bed volumes/h, was satisfactory. The sulfide oxidation proceeded quickly in aqueous media of various alkalinity, especially in those of strong alkalinity. As the transformation of sulfides to sulfates was accompanied by a drop of the pH value of the reaction medium, it was necessary to maintain it not lower than 6.0. Otherwise, the active bromine content in the resin decreased and the yield of the column process was unsatisfactory. Moreover, in acidic media a considerable part of sulfides transformed to elemental sulfur which contaminated the resin phase and caused turbidity of the effluent. By reacting a stoichiometric amount of reagents in batch regime not only sulfate, but also various intermediate products were found in the solution. The exhausted copolymer contained unsubstituted sulfonamide groups; it could be regenerated and reused repeatedly for the next processes.     

Blends of poly(vinyl chloride) (PVC)/natural rubber‐g‐(styrene‐co‐methyl methacrylate) for improved impact resistance of PVC

To improve the mechanical properties of poly(vinyl chloride) (PVC), the possibility of combining PVC with elastomers was considered. Modification of natural rubber (NR) by graft copolymerization with methyl methacrylate (MMA) and styrene (St) was carried out by emulsion polymerization by using redox initiator to provide an impact modifier for PVC. The impact resistance, dynamic mechanical analysis (DMA), and scanning electron microscopy (SEM) of St and MMA grafted NR [NR‐g‐(St‐co‐MMA)]/PVC (graft copolymer product contents of 5, 10, and 15%) blends were investigated as a function of the amount of graft copolymer product. It was found that the impact strength of blends was increased with an increase of the graft copolymer product content. DMA studies showed that NR‐g‐(St‐co‐MMA) has partial compatibility with PVC. SEM confirmed a shift from brittle failure to ductility with an increase graft copolymer content in the blends. The mechanical properties showed that NR‐g‐(St‐co‐MMA) interacts well with PVC and can also be used as an impact modifier for PVC. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 1666–1672, 2004     

Studies on the microstructure of vinyl/N‐phenylmaleimide copolymers by NMR and their applications

The micro‐ and stereostructures and sequence distribution of methyl methacrylate (MMA)/N‐phenylmaleimide (PMI) and styrene (St)–PMI copolymers were studied in detail with NMR spectroscopy. The MMA–PMI copolymer was in a random sequence distribution and the St–PMI copolymer was alternating in structure. Some micro‐ and stereoinformation of the MMA–PMI copolymers could be obtained from ¹H‐NMR spectra. The average number sequence length obtained from the copolymer triad by ¹³C‐NMR spectra was in agreement with that calculated from the reactivity ratios measured by an elemental analyzer. From the triad fraction of the copolymer measured by ¹³C‐NMR, the copolymer chain of MMA–PMI was proved to be a one‐order Markov chain. More suitable propagation reactions were proposed from the deviation of sequence distribution of the St–PMI copolymer. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 77: 2581–2587, 2000     

Study on the phase behavior of ethylene–vinyl acetate copolymer and poly(methyl methacrylate) blends by in situ polymerization

This study examines the phase behavior of ethylene–vinyl acetate copolymer (EVA) and poly(methyl methacrylate) (PMMA) blends during MMA polymerization. The ternary PMMA/MMA/EVA mixtures are considered to create a triangular phase diagram, which responds the phase changes during polymerization. The phase changes during MMA polymerization are also examined by optical microscope and photometer. Since the PMMA and EVA are well‐known immiscibles, the polymer solution undergoes phase separation at the initial stage of the MMA polymerization. Additionally, the phase inversion occurs as the conversion of MMA between 13.8 and 20.8%. On the other hand, the EVA‐graft‐PMMA, which can reduce the dispersed EVA particle size, is induced efficiently by taking tert‐butyl peroctoate (t‐BO) as initiator during MMA polymerization. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1001–1008, 2003     

Synthesis and characterization of novel poly(amide imide)s based on bis(p‐amidobenzoic acid)‐n‐trimellitylimido‐L‐leucine

N‐Trimellitylimido‐L ‐leucine was reacted with thionyl chloride, and N‐trimellitylimido‐L ‐leucine diacid chloride was obtained in a quantitative yield. The reaction of this diacid chloride with p‐aminobenzoic acid was performed in dry tetrahydrofuran, and bis(p‐amidobenzoic acid)‐N‐trimellitylimido‐L ‐leucine (5) was obtained as a novel optically active aromatic imide–amide diacid monomer in a high yield. The direct polycondensation reaction of the monomer imide–amide diacid 5 with 4,4′‐diaminodiphenylsulfone, 4,4′‐diaminodiphenylether, 1,4‐phenylenediamine, 1,3‐phenylenediamine, 2,4‐diaminotoluene, and benzidine (4,4′‐diaminobiphenyl) was carried out in a medium consisting of triphenyl phosphite, N‐methyl‐2‐pyrolidone, pyridine, and calcium chloride. The resulting novel poly(amide imide)s (PAIs), with inherent viscosities of 0.22–0.52 dL g^?1, were obtained in high yields, were optically active, and had moderate thermal stability. All of the compounds were fully characterized with IR spectroscopy, elemental analyses, and specific rotation. Some structural characterization and physical properties of these new optically active PAIs are reported. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 35–43, 2002; DOI 10.1002/app.10181     

Synthesis and characterization of poly[4‐(2‐thiazolylazo)phenyl methacrylate]‐co‐poly(methyl methacrylate)

A new methacrylic monomer, 4‐(2‐thiazolylazo)phenylmethacrylate (TPMA) was synthesized. Copolymerization of the monomer with methyl methacrylate (MMA) was carried out by free radical polymerization in THF solution at 70 ± 0.5°C, using azobisisobutyronitrile (AIBN) as an initiator. The monomer TPMA and the copolymer poly(TPMA‐co‐MMA) were characterized by Fourier transform infrared (FTIR), ¹H nuclear magnetic resonance (NMR), and elemental analysis methods. The polydispersity index of the copolymer was determined using gel permeation chromatography (GPC). Thermogravimetric analysis (TGA) of the copolymer performed in nitrogen revealed that the copolymer was stable to 270°C. The glass transition temperature (T_g) of the copolymer was higher than that of PMMA. The copolymer with a pendent aromatic heterocyclic group can be dissolved in common organic solvents and shows a good film‐forming ability. Both the monomer TPMA and the copolymer poly (TPMA‐co‐MMA) have bright colors: orange and yellow, respectively. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 2152–2157, 2007     

Synthesis of novel optically active poly(ester imide)s by direct polycondensation reaction promoted by tosyl chloride in pyridine in the presence of N,N‐dimethyformamide

4,4′‐Hexafluoroisopropylidene‐2,2‐bis(phthalic acid anhydride) (1) was treated with L ‐methionine (2) in acetic acid and the resulting 4,4′‐(hexafluoroisopropylidene)‐N,N′‐bis(phthaloyl‐L ‐methionine) diacid (4) was obtained in high yields. The direct polycondensation reaction of this diacid with several aromatic diols, such as bisphenol A (5a), phenolphthalein (5b), 1,4‐dihydroxybenzene (5c), 4,4′‐dihydroxydiphenyl sulfide (5 d), 4,6‐dihydroxypyrimidine (5e), 4,4′‐dihydroxydiphenyl sulfone (5f), and 2,4′‐dihydroxyacetophenone (5g), was carried out in a system of tosyl chloride (TsCl), pyridine (Py), and N,N‐dimethylformamide (DMF). The reactions with TsCl were significantly promoted by controlling alcoholysis with diols, in the presence of catalytic amounts of DMF, to give a series of optically active poly(ester imide)s, (PEI)s, with good yield and moderate inherent viscosity ranging from 0.43 to 0.67 dL/g. The polycondensation reactions were significantly affected by the amounts of DMF, molar concentration of monomers, TsCl and Py, aging time, temperature, and reaction time. All of the aforementioned polymers were fully characterized by ¹H NMR, FTIR, elemental analysis, and specific rotation. Some structural characterization and physical properties of these optically active PEIs are reported. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 455–460, 2006     

Synthesis,characterizations and thermal behavior of methyl methacrylate and N‐(p‐carboxyphenyl) methacrylamide/acrylamide copolymers

The synthesis, characterization, and thermal properties of copolymers of methyl methacrylate (MMA) and N‐(p‐carboxyphenyl) methacrylamide/acrylamide (CPMA/CPA) are described. The copolymerization was carried out in solution by taking different mole fractions (0.1–0.5) of CPMA/CPA in the initial feed using azobisisobutyronitrile as an initiator and dimethylformamide as a solvent at 60°C. The copolymer composition was determined from ¹H‐NMR spectra by taking the ratio of the proton resonance signal due to the  OCH₃ of MMA (δ = 3.59 ppm) and the aromatic protons (δ = 7.6–7.8 ppm) of CPMA/CPA. The monomer reactivity ratios of MMA:CPMA and MMA:CPA were determined using the Fineman Ross and Kelen Tudos methods and were found to be 1.32 ± 0.01 [MMA], 1.11 ± 0.02 [CPMA], 2.60 ± 0.01 [MMA], and 0.20 ± 0.01 [CPA]. Incorporation of these comonomers in the MMA backbone resulted in an improvement in the glass‐transition temperature and thermal stability. The percent char also increased with the increase of CPMA/CPA content in the copolymers. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 259–267, 2000     

Effect of compatibilizer in acrylonitrile‐butadiene‐styrene toughened nylon 6 blends: Ductile–brittle transition temperature

The ductile–brittle transition temperatures were determined for compatibilized nylon 6/acrylonitrile‐butadiene‐styrene (PA6/ABS) copolymer blends. The compatibilizers used for those blends were methyl methacrylate‐co‐maleic anhydride (MMA‐MAH) and MMA‐co‐glycidyl methacrylate (MMA‐GMA). The ductile–brittle transition temperatures were found to be lower for blends compatibilized through maleate modified acrylic polymers. At room temperature, the PA6/ABS binary blend was essentially brittle whereas the ternary blends with MMA‐MAH compatibilizer were supertough and showed a ductile–brittle transition temperature at ?10°C. The blends compatibilized with maleated copolymer exhibited impact strengths of up to 800 J/m. However, the blends compatibilized with MMA‐GMA showed poor toughness at room temperature and failed in a brittle manner at subambient temperatures. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 2643–2647, 2003     

Effect of methyl methacrylate on the properties of transparent flame retardant unsaturated phosphate ester copolymer

The effect of methyl methacrylate (MMA) on the properties of transparent flame retardant unsaturated phosphate ester copolymer (poly[UPE‐co‐MMA]) prepared by bulk polymerization technique was investigated. Fourier transform infrared spectra, gel fraction (G) test, and dynamic mechanical analysis revealed the structure and crosslinking density of poly(UPE‐co‐MMA) copolymers. The thermal degradation and flame retardancy of copolymers were indicated by thermogravimetric analysis, limiting oxygen index (LOI), and microscale combustion calorimeter (MCC) test. Besides, the mechanical properties and transparency were tested with testing machines and solid ultraviolet absorption spectra. As the MMA content increased to 50%, the copolymer contained 50 wt% MMA showed the maximal G (88.93%) and transmittance was up to 91.72%. From the poly(UPE‐co‐MMA) copolymers, the tensile strength increased from 14.62 to 26.95 MPa, assigned to the increase of crosslinking density of copolymers. The char yield of poly(UPE‐co‐MMA) was up to 21.18 wt%, which was a result of decomposition of phosphate groups, producing a phosphorus‐rich layer that increased the thermal stability of the residues. LOI and MCC results confirm that the introduction of MMA can retain the flame retardancy of copolymer remarkably. POLYM. ENG. SCI., 59:2103–2109, 2019. © 2019 Society of Plastics Engineers     

Synthesis of Bis(1H, 1H, 2H, 2H‐perfluoro‐octyl)methylenesuccinate copolymers and their application on cotton fabrics

Bis(1H, 1H, 2H, 2H‐perfluoro‐octyl)methylenesuccinate (FOM)/ethyl acrylate (EA)/methyl methacrylate (MMA) copolymer (FOME) latexes, FOM/butyl acrylate (BA)/MMA copolymer (FOMB) latexes, and FOM/octyl acrylate (OA)/MMA copolymer (FOMO) latexes were synthesized by continuous emulsion polymerization. Solution polymerization was also carried out to prepare FOMB. The influences of fluorine content and curing conditions on the surface properties of polymer films were discussed. The water and oil repellency of cotton fabrics treated with the FOM copolymers was better than that of conventional poly(fluoroalkyl acrylate)s containing the same fluorinated chain. The polymer films or the treated fabrics were characterized by Fourier transform infrared, scanning electron microscope, atomic force microscopy, thermogravimetric analysis, x‐ray photoelectron spectrometry, and wide angle x‐ray diffraction. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci, 2013     

Living Anionic Polymerization of <Emphasis Type="Italic">N</Emphasis>,<Emphasis Type="Italic">N</Emphasis>–Dimethylacrylamide and Copolymerization with Methyl Methacrylate in the presence of Bulky Aluminum Phenoxide

Summary Anionic polymerization of N,N–dimethylacrylamide (DMAAm) was examined in toluene with tert–butyllithium (t–BuLi)/bis(2,6–di–tert–butylphenoxy)ethylaluminum [EtA1(ODBP)₂]. In the presence of excess amounts of the aluminum compound over t–BuLi, the polymerization proceeded in a living manner. Sequential block copolymerization of DMAAm and methyl methacrylate (MMA) with the same initiator underwent smoothly in both directions, that is, polymerization of MMA by poly(DMAAm) living anions and vice versa. Moreover, the copolymerization of an equimolar mixture of DMAAm and MMA proceeded in a monomer–selective manner to give a block–like copolymer; DMAAm was polymerized first followed by MMA polymerization through selective activation of DMAAm by the coordination of EtA1(ODBP)₂.     

The dynamic mechanical analysis,impact, and morphological studies of EPDM–PVC and MMA‐g‐EPDM–PVC blends

The dynamic mechanical studies, impact resistance, and scanning electron microscopic studies of ethylene propylene diene terpolymer–poly(vinyl chloride) (EPDM–PVC) and methyl methacrylate grafted EPDM rubber (MMA‐g‐EPDM)–PVC (graft contents of 4, 13, 21, and 32%) blends were undertaken. All the regions of viscoelasticity were present in the E′ curve, while the E″ curve showed two glass transition temperatures for EPDM–PVC and MMA‐g‐EPDM–PVC blends, and the T_g increased with increasing graft content, indicating the incompatibility of these blends. The tan δ curve showed three dispersion regions for all blends arising from the α, β, and Γ transitions of the molecules. The sharp α transition peak shifted to higher temperatures with increasing concentration of the graft copolymer in the blends. EPDM showed less improvement while a sixfold increase in impact strength was noticed with the grafted EPDM. The scanning electron microscopy micrographs of EPDM–PVC showed less interaction between the phases in comparison to MMA‐g‐EPDM–PVC blends. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 71: 1959–1968, 1999     

Synthesis and characterization of diblock,triblock, and multiblock copolymers containing poly(3‐hydroxy butyrate) units

A poly[(R,S)‐3‐hydroxybutyrate] macroinitiator (PHB‐MI) was obtained through the condensation reaction of poly[(R,S)‐3‐hydroxybutyrate] (PHB) oligomers containing dihydroxyl end functionalities with 4,4′‐azobis(4‐cyanopentanoyl chloride). The PHB‐MI obtained in this way had hydroxyl groups at two end of the polymer chain and an internal azo group. The synthesis of ABA‐type PHB‐b‐PMMA block copolymers [where A is poly(methyl methacrylate) (PMMA) and B is PHB] via PHB‐MI was accomplished in two steps. First, multiblock active copolymers with azo groups (PMMA‐PHB‐MI) were prepared through the redox free‐radical polymerization of methyl methacrylate (MMA) with a PHB‐MI/Ce(IV) redox system in aqueous nitric acid at 40°C. Second, PMMA‐PHB‐MI was used in the thermal polymerization of MMA at 60°C to obtain PHB‐b‐PMMA. When styrene (S) was used instead of MMA in the second step, ABCBA‐type PMMA‐b‐PHB‐b‐PS multiblock copolymers [where C is polystyrene (PS)] were obtained. In addition, the direct thermal polymerization of the monomers (MMA or S) via PHB‐MI provided AB‐type diblocks copolymers with MMA and BCB‐type triblock copolymers with S. The macroinitiators and block copolymers were characterized with ultraviolet–visible spectroscopy, nuclear magnetic resonance spectroscopy, gel permeation chromatography, cryoscopic measurements, and thermogravimetric analysis. The increases in the intrinsic viscosity and fractional precipitation confirmed that a block copolymer had been obtained. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 1789–1796, 2004     

Study on soapless emulsion copolymerization methyl methacrylate and n-butyl acrylate

The soapless emulsion copolymerization of methyl methacrylate (MMA) and n-butyl acrylate (n-BuA) at four levels of monomer feed composition (f₁₀) was studied. Conversion (X), average particle diameter (D_p), molecular weight distribution (MWD), surface charge density, and glass transition temperature (T_g) of the copolymer as a function of reaction time (t) were measured. The copolymers obtained even at low conversion, except for the run of (f₁₀) = 90 wt. percent MMA, exhibit two T_gs in their DSC thermograms. Phase separation is found to occur in the latex particles during polymerization. The heterogeneous distribution of monomers in particles, in which a relatively rich MMA region exists in the shell and a relatively rich n-BuA region exists in the core of the particles, is assumed to arise from phase separation. The average copolymer composition and the fraction of the two domains are estimated. The polymerizatrion course and particle size growth follow the linear X vs. t² and D_p^3/2 vs. t relationships, respectively. Although the coagulation of particles happens after around 30 percent conversion, the polymerization behaviors, except for increasing rates, are not affected.     

Synthesis and characterization of new optically active poly(amide‐imide‐urethane) thermoplastic elastomers,derived from 4,4′‐(hexafluoroisopropylidene)‐N,N′‐bis(phthaloyl‐L‐leucine‐p‐aminobenzoic acid) and PEG‐MDI

A new class of optically active poly(amide‐imide‐urethane) was synthesized via two‐step reactions. In the first step, 4,4′‐methylene‐bis(4‐phenylisocyanate) (MDI) reacts with several poly(ethylene glycols) (PEGs) such as PEG‐400, PEG‐600, PEG‐2000, PEG‐4000, and PEG‐6000 to produce the soft segment parts. On the other hand, 4,4′‐(hexafluoroisopropylidene)‐N,N′‐bis(phthaloyl‐L ‐leucine‐p‐amidobenzoic acid) (2) was prepared from the reaction of 4,4′‐(hexafluoroisopropylidene)‐N,N′‐bis(phthaloyl‐L ‐leucine) diacid chloride with p‐aminobenzoic acid to produce hard segment part. The chain extension of the above soft segment with the amide‐imide 2 is the second step to give a homologue series of poly(amide‐imide‐urethanes). The resulting polymers with moderate inherent viscosity of 0.29–1.38 dL/g are optically active and thermally stable. All of the above polymers were fully characterized by IR spectroscopy, elemental analyses, and specific rotation. Some structural characterization and physical properties of this new optically active poly(amide‐imide‐urethanes) are reported. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2288–2294, 2004     

Enantioselective Silylcyanation of Aldehydes and Ketones by a Titanium Catalyst Prepared from a Partially Hydrolyzed Titanium Alkoxide and a Schiff Base Ligand

In the presence of small amount (0.2–1.0 mol%) of a titanium complex catalyst prepared from a partially hydrolyzed titanium alkoxide and an optically active tridentate Schiff base ligand, the enantioselective silylcyanation of aldehydes and ketones proceeded in a short reaction time at room temperature to afford the corresponding optically active cyanohydrin derivatives in excellent chemical yield with high enantiomeric excess (86–97% ee). The results indicate that partially hydrolyzed titanium alkoxides are a promising titanium source for the preparation of efficient catalysts for asymmetric synthesis.