Coionomeric mixtures of polyhydroxyethers and ethylene methacrylic acid copolymers. II. Compatibilizers for blends of polybutylene terephthalate and ethylene butyl acrylate copolymers

Blends of polybutylene terephthalate and ethylene butyl acrylate copolymers were studied at two extreme concentration levels so that each polymer would form, in turn, a particulate dispersed phase. The blends contained 5% by weight of a coionomeric compatibilizer, which was produced from 1 : 1 mixtures of a polyhydroxy ether of bisphenol A and the sodium ionomer of an ethylene methacrylic acid copolymer, using sodium ethoxide to enhance the formation of ionomeric clusters together with an A-B-A block oligomer to assist the solubilization of the two ionomeric polymers. In all cases the addition of the coionomeric compatibilizer mixture to the blend was found to decrease the size of the dispersed particles with a concomitant reduction in the interphase gap. It was also observed that the dispersed polymer exhibited a lower level of crystallinity and a slightly lower melting point than when it was present as a matrix, particularly for the case of the ethylene butylacrylate copolymer. The inability of the compatibilizer to completely prevent the formation of an interfacial gap which did not allow the blends to achieve more substantial improvements in mechanical properties, was attributed to the vast difference in crystallization temperature between the two polymers. © 1993 John Wiley & Sons, Inc.     

BECKMANN-Umlagerung und Fragmentierung; V. Teil Mechanismus der 7-Zentren-Fragmentierung von 1-Oxo-5-oximino-9-methyl-trans-decalin. Fragmentierungsreaktionen, 22. Mitteilung

The reaction rates of heterolytic fragmentation of 5-(p, -toluenesulfonyloxyimino)-1-oxo-9-methyl-trans-decalin ( 1 ), induced by sodium hydroxide in 80% ethanol and by sodium ethoxide in 100% ethanol, has been determined. The reaction of the oxime tosylate 1 with sodium ethoxide is first order with respect to both reactants. A similar base-dependence is observed in the reaction of the oxime tosylate 1 with sodium hydroxide. These results are explained in terms of an addition-fragmentation mechanism. This involves reversible addition of NaOH or NaOC₂H₅ to the carbonyl group of the oxime tosylate 1 and concerted fragmentation of the addition compounds 5a and 5b , yielding 9-cyano-6-methyl-trans-non-5-enoic acid ( 4a ) and the corresponding ethyl ester 4b , respectively. These reaction appear to be the first cases of concerted and stereospecific 7-centre fragmentation.     

Ionic miscibility enhancement via microion elimination in sulfonated polystyrene/poly(ethyl-acrylate-co-4-vinyl pyridine) ionomer blends

Miscibility enhancement of ionomer/ionomer and ionomer/polymeric acid systems is studied on the polymer pairs of poly(styrene-co-tetramethyl ammonium styrenesulfonate)/poly(ethyl acrylate-co-N-methyl-4-vinylpyridinium iodide) and poly(styrene-co-styrenesulfonic acid)/poly(ethyl acrylate-co-N-methyl-4-vinylpyridinium iodide). NMR and dynamic mechanical results show that in these blends direct macroion–macroion interaction can be achieved with the elimination of microcounterions from the polymer chains. Ion-ion attraction leads to a miscibility enhancement comparable to that of the previously reported proton transfer blends; a miscible blend is obtained with ca. 5 mol% of ions in the polymers.     

Synthesis,characterization, and fluorescence properties of dinuclear cadmium(II) complexes

Four dinuclear cadmium(II) complexes, [Cd₂(L¹)(μ₂-Cl)Cl₂] (1), [Cd₂(L²)(μ₂-Cl)Cl₂] (2), [Cd₂(L³)(μ₂-Cl)Cl₂] (3), and [Cd₂(L⁴)₃ClO₄] (4), where HL¹ = 4-methyl-2,6-bis(1-(2-piperidinoethyl)iminomethyl)-phenol, HL² = 4-methyl-2,6-bis(1-(2-pyrrolidinoethyl)iminomethyl)-phenol, HL³ = 4-methyl-2,6-bis(1-(2-morpholinoethyl)iminomethyl)-phenol and HL⁴ = 4-methyl-2,6-bis(cyclohexylmethyl)iminomethyl)-phenol, were synthesized. They were characterized by elemental analysis, FT-IR, UV–Vis, fluorescence and electronspray ionization mass spectroscopy. Complexes 1 and 4 were also characterized by single crystal X-ray analysis. The cadmiums atoms in 1 are linked by μ₂-chloride in a distorted square pyramidal geometry, whereas cadmium atom in 4 is in a distorted octahedral environment. The complexes show emission bands around 500 nm with excitation at 395 nm.     

Novel anionic polyaddition of 2‐trifluoromethylacrylate by double Michael reaction with ethyl cyanoacetate

Novel fluorinated polymer synthesis with anionic polyaddition by double Michael addition reaction of 2‐trifluoromethylacrylate derivatives with ethyl cyanoacetate (ECA) was proposed. Diaddition product of ECA with phenyl 2‐trifluoromethylacrylate was yielded in high yield by the catalysis of sodium ethoxide in tetrahydrofuran at 60 °C. Sodium hydroxide catalyzed double Michael addition reaction also produced diaddition product in high yield. Novel anionic polyaddition of 1,4‐phenylene bis(2‐trifluoromethylacrylate) [CH₂?C(CF₃)COOC₆H₄OCOC(CF₃)?CH₂] (PBFA) with ECA afforded the polymer of 1.2 × 10⁴ as the highest molecular weight. The isolated polymer gave the polymer of 2.8 × 10⁴ as a molecular weight by the reaction of the isolated polymer with PBFA in the presence of sodium ethoxide; which proved that the polymer end groups were mainly ECA moieties. The reaction mechanism that the proton abstraction from ECA followed by the addition of 2trifluoromethylacrylate was proposed. The reaction of acetylacetone with PBFA was also examined to give the polymer of 7.6 × 10³ as the highest molecular weight catalyzed by sodium hydroxide at room temperature. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5698–5708, 2009     

Dynamic mechanical properties of polystyrene ionomers containing both carboxylate and sulfonate anionic groups

Polystyrene‐based ionomers possessing sodium methacrylate (MA) and sodium styrenesulfonate (SS) units in each polymer chain [poly(styrene‐co‐methacrylate‐co‐styrenesulfonate) (PSMA‐SS)] were synthesized. The dynamic mechanical properties of PSMA‐SS ionomers were studied and compared with those of styrene ionomers containing only MA (PSMA ionomer) or SS (PSS ionomer) units. It was observed that the ionic moduli of PSMA‐SS ionomers depended directly on the total ion content and that the ionic modulus was highest for the PSMA ionomer and lowest for the PSMA‐SS ionomer. The matrix T_gs of the three ionomer systems were found to be similar to each other; the cluster T_g of PSMA‐SS ionomer was higher than that of PSS ionomer at low SS contents but became closer to each other at high SS contents. In addition, the small‐angle X‐ray scattering study revealed that the multiplet size might be in the following order: PSMA‐SS > PSS > PSMA. This implied that at the same ion content, the fractions of cluster regions were smallest for PSMA‐SS ionomer in comparison with those of PSS or PSMA ionomers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012     

Chalcogenopyranones from disodium chalcogenide additions to 1,4-pentadiyn-3-ones. The role of enol ethers as intermediates

Enol ethers 9 are formed as a mixture of E- and Z-isomers from the addition of ethanol to 1,4-pentadiyn-3-ones 2 in sodium ethoxide/ethanol. The enol ethers react with disodium chalcogenides to give the corresponding 2,6-disubstituted chalcogenopyranones 1 bearing alkyl, aryl, or heteroaryl substituents in high yield as the only heterocyclic product of reaction. Diynones 2 react with disodium chalcogenides to give mixtures of products in which the chalcogenopyranones 1 are minor components and the dihydrochalcogenophenes 3 are the major products. The addition of hydrogen sulfide to diynone 2b in ethanol gives a product mixture nearly identical to that observed for the addition of disodium sulfide in sodium ethoxide in ethanol to 2b . Intermediates for the addition of hydrogen chalcogenides and disodium chalcogenides to both 2 and 9 are described, which lead to the heterocyclic products.     

Synthesis of 4-aminothieno[2,3-b] pyridine-5-carboxylie acids

2-Amino-3-cyanothiophenes were reacted with ethyl aminocrotonate in the presence of catalytic amounts of p-toluensulfonic acid. The intermediates 2-[N-(3′-ethoxycarbonyl-2′-propenylamino]-3-cyanothiophenes obtained were cyclized with sodium ethoxide to give the desired ethyl 4-aminothieno[2,3-b] pyridine-5-carboxylate. Hydrolysis of the latter aminoesters afforded 4-aminothieno[2,3-b]pyridine-5-carboxylic acid. The overall yields were about 80%.     

pH-Responsive Nanocomposites From Methylcellulose and Attapulgite Nanorods: Synthesis,Swelling and Absorption Performance on Heavy Metal Ions

A pH-responsive methylcellulose-g-poly(sodium acrylate)/attapulgite (MC-g-PNaA/APT) nanocomposite superabsorbent was prepared by the free-radical solution polymerization of methylcellulose (MC), sodium acrylate (NaA) and nanoscale attapulgite (APT) in the presence of the crosslinker N,N′-methylene-bis-acrylamide (MBA). The structure and morphology of the nanocomposite were characterized by FTIR, FESEM, TEM, XRD and EDS techniques, and the effects of the amount of MBA, MC and APT nanorods on swelling behaviors were also evaluated. Results indicate that NaA has been grafted onto MC macromolecular chains and APT nanorods participated in polymerization by its active silanol groups, and APT led to a better dispersion in the MC-g-PNaA matrix. The incorporation of APT clearly enhanced the swelling capacity and rate of the superabsorbent. In addition, the nanocomposite exhibited excellent absorption capacity on heavy metal ions, and its absorption amounts on Ni²⁺, Cu²⁺ and Zn²⁺ ions reached 9.86, 7.66 and 21.86 times greater than active carbon (AC). The biopolymer-based nanocomposite superabsorbents can be used as a potential water-saving material and candidate of AC for heavy metal ion absorption.     

Plasticization of a poly(ethyl acrylate) ionomer by an alkyl aniline

The plasticization by 4-decylaniline (4DA) of a microphase-separated poly(ethyl acrylate) ionomer containing sodium carboxylate groups is examined. Dynamic mechanical thermal analysis, supplemented by differential scanning calorimetry, shows that the matrix and cluster glass transitions (T_g's) in the ionomer are both depressed by ca. 1°C/wt % 4DA; this, in turn, is similar to the T_g depression in the blend of the parent poly(ethyl acrylate) (PEA) with 4DA. There is no evidence of 4DA crystallinity in the blend. Small-angle x-ray scattering (SAXS) measurements show that the ionomer peak increases in intensity and decreases in scattering angle with increasing concentration of 4DA in the blend; the corresponding Bragg spacing, initially at 2.3 nm, increases by ca. 0.04 nm/wt % 4DA. These results, supported by preliminary spectroscopic measurements, are attributed to hydrogen bonding interactions between the amine groups of 4DA and the ester groups in PEA and the ionomer, rendering the blend miscible. It is argued that the uniform distribution of 4DA throughout the material plasticizes both phases of the ionomer by adding free volume; this also accounts for the increase in the characteristic spacing detected by SAXS.     

Synthesis and optical properties of poly(aryl ether ketone)s incorporating porphyrins in the backbones

A series of novel soluble poly(aryl ether ketone)s (PAEKs) based on 5,10‐bis(4‐hydroxyphenyl)?15,20‐diphenylporphyrin (cis‐DHTPP), 4,4′‐(hexafluoroisopropylidene) diphenol (6FBPA) and 4,4′‐difluorobenzophenone (DFB) were synthesized and characterized by FT‐IR, ¹H‐NMR, UV–vis and fluorescence spectroscopies. The intrinsic photophysical properties of porphyrins were preserved because of the absence of photoinduced electron transfer in the polymer chains. Investigation of the copolymers thermal properties indicated that these polymers had high glass transition temperatures and excellent thermal stabilities. The results of Z‐scan and optical limiting measurements manifested that incorporation of the porphyrin chromophore into the main chain engendered the novel PAEKs with superior nonlinear optical properties and optical limiting function, which could be effectively tuned by varying the molar ratio of porphyrin monomers. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 1282–1290     

Synthesis, Reactions, and Anti-inflammatory Activity of Heterocyclic Systems Fused to a Thiophene Moiety Using Citrazinic Acid As Synthon

Summary. A series of pyridines, pyrimidinones, and oxazinones were synthesized as anti-inflammatory agents using citrazinic acid (2,6-dihydroxyisonicotinic acid) as a starting material. Acryloyl pyridine was treated with cyanothioacetamide to give cyano pyridine-thione, which was reacted with ethyl chloroacetate to yield the corresponding amino ester. The ester was hydrolysed to the sodium salt, which was treated with acetic anhydride to afford 2-methyloxazinone, which was treated with ammonium acetate to afford 2-methylpyrimidinone followed by methylation with methyl iodide to yield 2,3-dimethylpyrimidinone. In addition, the oxazinone derivative was reacted with aniline or hydrazine hydrate to give 3-phenyl- or 3-aminopyrimidinones. The latter reacted with thiophene-2-carboxaldehyde or phenylisothiocyanate to afford Schiff’s bases or thiosemicarbazides. 3-Aminopyrimidinone was treated with phthalic anhydride or 1,2,4,5-benzenetetracarboxylic acid dianhydride or toluene-3,5-diisocyanate to afford the corresponding imide, bis-imide, and bis-semicarbazide derivatives. The pharmacological screening showed that many of these compounds have good anti-inflammatory activity comparable to Prednisolone^? as reference drug.     

Mechanism of Disulfide–Disulfide Interchange in Polysulfide Polymer Melt Blend by Electron Ionization Mass Spectrometry. II

Abstract

The degree of randomization, q, of structural units in melt blends of the polysulfide homopolymers A(PS1) and B(PS2), wherein the disulfide equivalents D _A/D _B = 1, were studied by electron ionization mass spectrometry. Over the temperature range of 207–219°C, the relaxation process, due to the dominant disulfide–disulfide interchange reactions, is postulated to follow an associative reaction mechanism. These intermolecular disulfide–disulfide interactions promote a transient enhancement of the sulfur rank in the activated complex resulting in formation of the randomized co‐polymer AB. The mass spectrometric experimental design enabled measurement of concentrations of reactants A(PS1) and B(PS2), as well as the randomized copolymer AB, by monitoring the abundance of dimer units a₂, b₂, and ab, respectively as a function of time. The degree of randomization, q, was observed in the absence of catalysts or solvents, notwithstanding the solvent/solute and solute/solvent characteristics of the polymer melt blend. The mechanism of this randomization process, was rationalized on the basis of the properties of sulfur, aided by the observation of macrocyclic monomeric and dimeric units during the retro‐polymerization reactions under the EI/MS conditions employed. The model polysulfide polymers A(PS1) and B(P52), used in this study were synthesized from bis(2‐chloroethyl)ether and bis(2‐chloro ethoxy)methane, respectively.     

Synthetic transformations of higher terpenoids: XX. Synthesis and transformations of diterpene ureido esters

Lossen rearrangement of N-hydroxymaleopimaric acid amide p-toluenesulfonate in the presence of amines in methanol led to the formation of the corresponding diterpene ureido esters with high regio- and stereoselectivity. Treatment of the resulting ureides with phosphoryl chloride gave cyclic amidines via intramolecular ring closure. Substituted hydantoins were obtained by reactions of the ureido esters with glyoxal in acid medium, and their treatment with sodium ethoxide in ethanol afforded compounds of the naphtho[1,2-h]-quinazoline series.     

3-Oxo-1,2-benzoisothiazoline-2-acetic acid 1,1-dioxide derivatives. II. Reaction of amides with alkoxides

Reaction of some 3-oxo-1,2-benzoisothiazoline-2-acetamide 1,1-dioxides ( 1a-f ) with alkaline alkoxides was carried out under various conditions. Under mild conditions, 1a-f with sodium methoxide gave o-(N-carbox-amidomethylsulfamyl)benzoic acid methyl esters ( 2a-f, R = CH3 ). Compounds 1a or 2a reacted with sodium alkoxides under drastic conditions affording only ester 5 . Under the same conditions, 1b-d or 2b-d gave 4-hydroxy-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxides ( 3b-d ), while 1e-f or 2e-f afforded the acid 6 in variable amounts, together with the expected benzothiazines 3e-f . Isolation of ethyl ether as another product in the reaction of 1e-f with sodium ethoxide supports the suggestion that the formation of 6 involves the O-alkyl fission on the alkyl carbon of the esters 2e-f . An explanation of these results may be related to the acidic character of the amide hydrogen in compounds 2e-f .     

Reaction of cellulose phosphonate with N-vinyl-2-pyrrolidone and flame-retardant properties of the product

The reaction of cellulose phosphonate and N-vinyl-2-pyrrolidone in ethanol in the presence of sodium ethoxide was investigated and thermal stabilities and flame-retardant properties for cellulose phosphonate modified with N-vinyl-2-pyrrolidone were discussed. The results in this study point out the following important aspects of flame retardation of cellulose fabrics: (1) The reaction of cellulose phosphonate and N-vinyl-2-pyrrolidone in the presence of sodium ethoxide results in graft polymerization of N-vinyl-2-pyrrolidone at P? H sites in cellulose phosphonate; an average chain length of the graft polymer is about five units of vinylpyrrolidone. (2) The graft polymerization of N-vinyl-2-pyrrolidone can improve both stabilities, especially the flame-retardant properties of cellulose fabrics. (3) Amides, whether noncyclic or cyclic, are suitable for nitrogen compounds that can effectively operate as synergists.     

Effect of Specific Interactions on Structure-Property Relationships of Thermoplastic IPNs Based on Polyurethane and Styrene-co-Acrylic Acid Ionomers

Summary: The structure-property relationships of thermoplastic polymer blends based on poly(ether-urethane) ionomer (PEUI) and K⁺-Ion containing styrene-acrylic acid random copolymer (S-co-AA(K)) have been investigated by different methods. Convergence of the glass transition temperature values of the PEUI and the S-co-AA(K) components in the blends studied and improvement of end-use properties have been found.     

Effect of Na‐ionomer on dynamic rheological,dynamic mechanical and creep properties of acrylonitrile styrene acrylate (ASA)/Na+1 poly (ethylene‐co‐methacrylic acid) ionomer blend

A special class of engineered copolymers, called ionomers, comprising both electrically neutral repeating units and a fraction of ionized units was melt blended to weather resistant acrylonitrile/styrene/acrylate (ASA) terpolymer for improved electrical conductivity, heat sealing ability, direct adhesion to several polymers, glass and metals without affecting the aesthetics and colorability of ASA. The similar chemical nature of one of the components of each blended materials viz. acrylate rubber in ASA and acrylic acid of Na‐ionomer in addition to the presence of ionic crosslinking within Na‐ionomer, polar acrylonitrile group in ASA affects chain dynamics as compared to neat polymers. In this context, dynamic rheological properties, DMA properties, creep behavior and DSC of the newly developed ASA/Na‐ionomer blends were analyzed. Based on Na‐ionomer content, the blend system either forms “mushroom” or “brush” type conformation and formation of ionic crosslinking in “brush regime” leads to three tiers Caylay tree conformation. The different chain topology resulted into characteristic loss modulous (G″) curve during stress relaxation process. The chain conformation as well as ionic crosslinking and ion–dipole interaction between the blend components also affected DSC endotherm peak and glass transition temperature. The tan δ peak temperature from DMA also revealed the similar observation. The creep compliance of the blends was dependent on Na‐ionomer content and with temperature. The Findley model analysis of creep compliance suggested that the creep compliance was depended on Na‐ionomer content and ionic crosslinking controlled the creep. The findings can be utilized to design weather resistant smart polymer using suitable filler system. Copyright © 2014 John Wiley & Sons, Ltd.     

Sulfolanylation of malonic acid derivatives

-Alkoxysulfolanes in the presence of equimolar amounts of sodium ethoxide react with malonic acid derivatives in which the hydrogen atom of the methylene group is activated by CN, COOR, CONH₂, and SO₂R substituents to give compounds that are identical to the products of the reaction with 2-sulfolene. A possible scheme for the reaction is proposed on the basis of the experimental data and the PMR spectra.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 767–769, June, 1972.