Acrylic Anhydride Research Articles

Ring‐opening‐closing alternating copolymerization via zwitterion intermediates

AbstractThe present paper describes comprehensive results based on a new concept, i.e., ring‐opening‐closing alternating copolymerization. The copolymerization is given by combinations of ring‐opening of a cyclic monomer (A) and ring‐closing of a non‐cyclic monomer (B). The cyclic monomers used are five‐, six‐, and seven‐membered cyclic phosphonites and 2‐methyl‐2‐oxazoline. As a monomer (B), muconic acid, dialdehydes, di(meth)acrylic anhydrides, and N‐methyldiacrylamide are used. A 1:1 mixture of these monomers produced an alternating copolymer having a ring‐opened and a ring‐closed structural unit. A mechanism involving zwitterion intermediates is considered in all copolymerizations.

Ring-opening-closing alternating copolymerization of cyclic phosphonites with methacrylic and acrylic anhydrides

Copolymerization of cyclic phosphonites (1a-c) with methacrylic and acrylic anhydrides (2a and 2b, respectively) has been investigated. The results show that a 1:1 mixture of monomers produces an alternating copolymer with one part of the repeating unit coming from the ring opening of monomer 1 and the other part from the ring closing of 2 (ring-opening-closing alternating copolymerization (ROCAC)). In the copolymerization of 1 with 2a under some conditions, the quantitative cyclization of 2a took place to form an alternating copolymer of 3a, whereas a small amount of pendent unsaturation was observed in the copolymerization of 1 with 2b

Kinetics, mechanisms, and synthesis studies of ring‐opening‐closing alternating copolymerization

AbstractThe present paper describes the ring‐opening‐closing alternating copolymerization of cyclic phosphonites (2‐phenyl‐1,3,2‐dioxaphosphelane (1a), 2‐phenyl‐1,3,2‐dioxaphosphorinane(1b), 2‐phenyl‐1,3,2‐dioxaphosphepane(1c), and 2‐phenyl‐4H‐1,3,2‐benzodioxa phosphorin‐4‐one(1d)) with muconic acid(2a), succinaldehyde(2b), glutaraldehyde(2c), adipinaldehyde(2d), o‐phthalaldehyde(2e), acrylic anhydride(2f), methacrylic anhydride(2g), N‐methyl diacrylamide(2h), and N‐methyldimethacrylamide(2i). The reaction of a 1:1 monomer feed ratio, explained by a mechanism of propagation via zwitterion intermediates, proceeds without any added catalyst to give an alternating copolymer 3 involving ring‐opening of 1 and ring‐closing of 2. The structure of copolymer 3 was determined by1 H,13 C NMR,31 P NMR and IR spectroscopies as well as elemental analysis.

Cyclopentadienyl-, Indenyl- und Trifluormethylcyclopentadienyl-Cobalt-Komplexe mit Akzeptor-substituierten Olefinen als Liganden / Cyclopentadienyl, Indenyl and Trifluoromethylcyclopentadienyl Cobalt Complexes with Acceptor-Substituted Olefins as Ligands

The complexes C5H5Co(PMe3)2 (1), C9H7Co(PMe3)2 (2) and (C5H4CF3)Co(PMe3)2 (3) react with mono- and disubstituted ethenes such as styrene, acrylic acid methylester, methylvinylketone, acroleine, acrylic acid amide, acrylonitrile, maleic anhydride, maleic and fumaric acid dimethylester, and fumaric dinitrile to give the olefin(phosphane)cobalt compounds (ring)Co(PMe3)(olefin) (4-32) in good to excellent yields. With acrylonitrile, two different rotamers are obtained which indicates that there is a considerable energy barrier for rotation around the metal-olefin bond. The reactions of 1 and 3 with maleic acid dimethylester (MDE) lead not only to the formation of the expected products (ring)Co(PMe3)(MDE) (22, 23) but also to the thermodynamically favored isomers (ring)Co(PMe3)(FDE) (24, 26) containing fumaric acid dimethylester (FDE) as ligand. A similar isomerization has been observed upon treatment of 2 and 3 with fumaric dinitrile (FDN) which gives besides the complexes (ring)Co(PMe3)(FDN) (29, 31) also the maleic dinitrile (MDN) derivatives (ring)Co(PMe3)(MDN) (30, 32). The olefin(trimethylphosphane)cobalt compounds are surprisingly inert and neither on photolysis nor on heating give the isomeric hydrido(vinyl)metal complexes.

Synthèse et copolymérisation d'acrylamides comportant le groupement dihydroxyphosphoryloxyalkyle

Abstractω‐Aminoalkyl dihydrogen phosphates 5a–c, 7 and 9 were obtained in a simple and reproducible fashion by O‐phosphorylation of the corresponding aminoalcohols with ClPO3H2 generated in situ by controlled hydrolysis of POCl3. Reaction of these phosphates with acrylic or methacrylic anhydride in water/THF mixture afforded a series of new acrylic monomers (11a–h) bearing a phosphoryl group. Inverted emulsion copolymerization of the latter with the hydrophilic comonomers N‐[1,1‐bis(hydroxymethyl)‐2‐hydroxyethyl]acryl‐ or methacrylamide (12a or 12b) and with the cross‐linker N,N′‐methylenediacrylamide (13) afforded various gels in the form of spherical beads. Preliminary experiments showed that some of these copolymers could be efficiently used as stationary phases for the separation of proteins by ion‐exchange chromatography.

The dependence of cyclopolymerizability of acrylic and methacrylic anhydrides on various conditions: New interpretation of temperature dependency of cyclization constant in radical cyclopolymerization of nonconjugated dienes

AbstractThe cyclization constant Kc in the radical cyclopolymerization of acrylic and methacrylic anhydrides was evaluated in detail under various conditions. No linear relationship between in Kc and 1/T was observed; cyclization was acceleratively enhanced at elevated temperatures. The Kc values also increased with decreased monomer concentration and increased solvent polarity. These increasing dependencies of Kc are ascribed to the increased significance of depropagation, demonstrating a new interpretation of the temperature dependence of the cyclization constant in the radical cyclopolymerization of nonconjugated dienes.

Ionomer/ionomer thermoplastic IPNs based on poly(n‐butyl acrylate) and polystyrene

AbstractThermoplastic interpenetrating polymer networks (IPNs) were prepared by combining poly(n‐butyl acrylate) with polystyrene, both polymers crosslinked independently with acrylic acid anhydride (AAA). Decrosslinking of both polymers was carried out by hydrolysis of the anhydride bonds. Neutralization of the carboxylic acid groups to form the ionomer was carried out in a Brabender Plasticorder. Two subclasses of thermoplastic IPNs were studied: (1) Chemically blended thermoplastic IPNs (CBT IPNs) were prepared by synthesizing polymer II in polymer I in a sequential synthesis; (2) mechanically blended thermoplastic IPNs (MBT IPNs) were prepared by melt blending separately synthesized polymers. Rheovibron characterization revealed that of the two combinations, the CBT IPNs were better mixed than the MBT IPNs. Investigations of phase continuity via melt viscosity and modulus suggest that the CBT IPNs have some degree of dual phase continuity. Transmission electron microscopy suggests dual phase continuity and relatively small phase domains, 2000–5000 Å for the CBT IPNs. The mechanical properties from tensile and Izod impact tests showed that the CBT IPNs were stronger than the MBT IPNs.

Equilibrated radical polymerization of acrylic propionic anhydride as a mono‐ene counterpart of acrylic anhydride

AbstractRadical polymerization of acrylic propionic anhydride (APA) as a mono‐ene counterpart of acrylic anhydride (AA) was investigated in order to obtain supporting evidence for a previously proposed mechanism based on polymerization equilibrium for the cyclopolymerization of AA. The deviation from first‐order dependence of the rate of polymerization Rp on monomer concentration was enhanced by a decrease in monomer concentration. The Arrhenius plot of lnRp vs. 1/T was clearly curved in a highly dilute system. These results suggest increased significance of the depropagation reaction equilibrated with propagation under polymerization conditions favorable to five‐membered ring formation in cyclopolymerization of AA. Under these conditions, the disproportionation reaction of APA became important and the liberated AA was incorporated into the polymer chain through copolymerization with APA, resulting in poly(APA‐co‐AA) having five‐membered anhydride units.

Molecular demixing in poly[cross‐(ethyl acrylete)]‐inter‐poly[cross‐(methyl methacrylate)] interpenetrating polymer networks brought about by selective decrosslinking and annealing

AbstractThe extent of molecular demixing of poly[cross‐(ethyl acrylate)]‐inter‐poly[cross‐(methyl methacrylate)] interpenetrating polymer networks (PEA/PMMA IPNs), of mid‐range composition was investigated by decrosslinking and/or annealing using dynamic mechanical spectroscopy. A single broad transition characteristic of extensive but incomplete molecular mixing was observed for the PEA/PMMA IPN. The presence of crosslinking in both phases of an IPN enhances the mutual miscibility of the polymers. Through the use of a labile crosslinker, acrylic acid anhydride (AAA), polymer networks may be decross‐linked, allowing the chains to separate and form two distinct phases. Annealing further sharpens the transitions, and phase separation becomes most pronounced when decrosslinking is followed by annealing.

Some intramolecular michael additions of adenine derivatives

AbstractIn our attempts to prepare polymerizable derivatives of nucleic acid bases, we investigated the reaction of adenine (1) and 9‐(cyanoethyl)adenine (4) with acrylic anhydride and acryloyl chloride. Reactions of adenine with methyl acrylate and vinyl acrylate were also examined. The results show that these reactions are solvent dependent and the intermediate acryloyladenine 3 can undergo a facile intramolecular Michael reaction to form 7.

Head‐to‐head vinyl polymers. XI. Preparation and characterization of poly(methyl acrylate) and poly(methyl methacrylate) consisting of head‐to‐head and head‐to‐tail units through cyclopolymerization of acrylic and methacrylic anhydrides

AbstractAcrylic anhydride (AAn) and methacrylic anhydride (MAAn) were polymerized with radical initiator in polar solvents at high temperatures. The polymers obtained were found to consist of five‐and six‐membered ring structures by comparing IR spectra of the polymers with those of model compounds, succinic anhydride, and glutaric anhydride. Hydrolysis and methylation of the polymers gave new polymers composed of head‐to‐head (HH) and head‐to‐tail (HT) methyl acrylate (MA) or methyl methacrylate (MMA) units. The content of HH unit of these HH/HT polymers was determined by 1H‐NMR and 13C‐NMR spectra. The softening, glass transition, and thermal degradation temperatures of the poly(MA) with HH and HT units were found to somewhat increase with increasing of the content of the HH units. On the other hand, the glass transition and thermal degradation temperatures of the poly(MMA) with HH and HT units increased similarly, but the softening temperature decreased as the content of the HH units increased.

A survey of dual phase continuity and miscibility in interpenetrating polymer networks, making use of selective decrosslinking and dissolution of one component: Poly(n‐butyl acrylate)/polystyrene

AbstractA sequential interpenetrating polymer network, IPN, may be defined as a combination of two polymers in network form, at least one of which was polymerized or crosslinked in the presence of the other. Two major problems of interest to sequential IPN's relate to phase continuity and extent of mixing within each phase. A first attempt to define the molar volume of a network is made in terms of the molar volume of the polymer between crosslinks. This permits a thermodynamic calculation of the changes in molecular mixing expected as a function of crosslink density. The experimental system was poly(n‐butyl acrylate)/polystyrene IPN's, where the PnBA was crosslinked with acrylic acid anhydride. This last may be selectively hydrolyzed, forming a semi‐IPN, and then the PnBA can be extracted. Scanning electron microscopy and dynamic mechanical spectroscopy were carried out at each stage.

A comparative study of semi‐2 and full interpenetrating polymer networks based on poly(n‐butyl acrylate)/polystyrene

AbstractSequential poly(n‐butyl acrylate)/polystyrene (PnBA/PS) semi‐2 and full IPN's of various compositions were made by UV photopolymerization. Acrylic acid anhydride and divinylbenzene were used as labile and permanent crosslinkers, respectively, for the rubbery phase and the plastic phase. After IPN formation, network I was selectively decrosslinked. After extracton of polymer I, the remaining PS network II was characterized by swelling measurements and examined by scanning electron microscopy. It was found that crosslinked PnBA affects the formation of the second network more than uncrosslinked PnBA does. A porous phase formed by an aggregate of spherical polystyrene domains was observed. The experimental domain diameter was in good agreement with previous theoretical values. The dynamic mechanical properties of full IPN's, decrosslinked IPN's, and semi‐2 IPN's were also studied. A significant level of molecular mixing was found for full IPN's of midrange compositions. The major difference between the full IPN's and the decrosslinked IPN's is that the glass transitions of the respective polymers become more pronounced in the latter case, with a deeper valley between them. With the destruction of the crosslink sites, there is no longer a forced miscibility of the interlocked phases, which are, in fact, thermodynamically incompatible.

Further discussion of the cyclopolymerization of acrylic anhydride in terms of ring size control

AbstractRadical cyclopolymerization of acrylic anhydride (AA) was conducted under various polymerization conditions to yield highly cyclized polymer, and the content of the five‐membered ring of cyclic poly‐AA obtained was examined in detail. Five‐membered ring formation was favored with increased solvent polarity, raised polymerization temperature, and decreased monomer concentration; the ring size of the cyclic structure could be controlled freely by choosing appropriate polymerization conditions. In addition to these results, the rate of polymerization and the molecular weight of the polymer were reduced under polymerization conditions where the five‐membered ring formation was favored. Finally, a mechanistic discussion is given in order to interpret these results; a reaction scheme for propagation based on polymerization equilibrium is proposed.

Effect of solvent and temperature on the cyclopolymerization of acrylic and methacrylic anhydrides leading to five‐or six‐membered ring formation

Effect of solvent and temperature on the cyclopolymerization of acrylic and methacrylic anhydrides leading to five‐or six‐membered ring formation

Synthesis, characterization, and viscoelastic behavior of single‐phase interpenetrating polystyrene networks

AbstractSingle phase interpenetrating polystyrene networks were synthesized using a room temperature photopolymerization method. Divinylbenzene was used for crosslinking both networks in most cases; a few IPNs were prepared using acrylic acid anhydride to provide labile crosslinkages in the primary network. The IPNs were characterized by means of equilibrium swelling in toluene. The results of these experiments closely approached the predictions of a swelling equation derived under the assumption that the two networks were elastically independent. Deviations from the swelling equation predictions could be explained in terms of contributions from internetwork entanglements. Small amplitude dynamic mechanical measurements indicated that the presence of the small amount (∼10 percent) of tight primary network chains had no perceptible effect on the linear viscoelastic properties.

Radiation degradation susceptibility of vinyl polymers: Nitriles and anhydrides

AbstractThe effect of γ irradiation on a series of vinyl polymers, which included polymethacrylonitrile, poly(α‐chloroacrylonitrile), poly(dimethyl itaconate), poly(acrylic anhydride), and poly(methacrylic anhydride), was studied as part of a program to develop improved positive lithographic resists. Radiation‐induced degradation was observed for polymethacrylonitrile, poly(α‐chloroacrylonitrile), and poly(methacrylic anhydride). Molecular weight degradation as a function of dose was monitored by membrane osmometry or GPC techniques. For γ‐irradiated poly(dimethyl itaconate) and poly(acrylic anhydride) crosslinking was found to predominate over chain scission. [G(s)–G(x)] values, calculated from molecular weight inverse versus dose curves, indicate that both nitrile polymers degraded more efficiently than a poly(methyl methacrylate) reference standard on the basis of Mn changes. The radiation behavior of the first three polymers confirms earlier findings than vinyl polymers with quaternary carbons predominantly degrade when subjected to ionizing radiation.

Participation of polyenes in conjugated Diels-Alder and alternating copolymerization reactions

1. Trienes which have two conjugated double bonds and an isolated double bond separated from them by two σ bonds undergo conjugated diene synthesis and alternating copolymerization reactions with acrylic acids and maleic anhydride. 2. The diene synthesis reaction is probably facilitated by the special features of the structures of the polymeric molecule formed in the alternating copolymerization.

Effect of decrosslinking and annealing on interpenetrating polymer networks prepared from poly(ethyl acrylate)/polystyrene combinations

Interpenetrating polymer networks, IPN polymers, were prepared from poly(ethyl acrylate), PEA, and polystyrene, PS. Part or all of the crosslinking monomer was acrylic acid anhydride, AAA, which was subsequently hydrolysed and the samples annealed. Modulus-temperature, modulus-time (during annealing) determinations, and transmission electron microscopy were performed on the freshly made samples, after hydrolysis, and after annealing. The studies show that the phase continuity of the PS component is increased relative to the PEA component on annealing, and the separation of the phases becomes more pronounced. A new morphology was observed with the totally decrosslinked, chemically induced blend, with the PEA showing both a continuous and a discontinuous aspect.

Free radical polymerization of unconjugated dienes: 19. Temperature dependence of the cyclopolymerization of o-divinylbenzene

The temperature dependence of the extent of cyclization in the free radical polymerization of o-divinylbenzene has been investigated. The results have been interpreted on the basis of a kinetic relationship derived by assuming that three different cyclization reactions can occur during the chain growth: it has been found that of these reactions one largely prevails over the others. The difference between the activation energy of the main cyclization reaction and that of the intermolecular addition of the growing chain onto a monomer molecule compares well with the analogous differences already found in the cyclopolymerizations of acrylic and methacrylic anhydrides. The corresponding difference between the activation entropies is in highly satisfactory agreement with the one which can be calculated for the formation of a seven-membered ring structure. Both these facts strongly support the hypothesis that, in the main cyclization reaction occurring in the free radical polymerization of o-divinylbenzene, benzocycloheptene structures, practically free of strain, are formed.