Synthesis and characterization of piperazine-derived poly(amido-amine)s with different distributions of amido- and amino-groups along the macromolecular chain

Four poly(amido-amine)s based on piperazine have been synthesized by poly(acylation-addition) reaction of piperazind with various activated derivatives of acrylic acid. In these polymers, amido-, and amino groups are randomly arranged along the macromolecular chain. These polymers have been fully characterized by hydrolytic analysis, ¹³C n.m.r., and potentiometric techniques.     

Surface-grafted heparinizable materials

Poly(amido-amine) chains have been grafted on the surface of different materials including glass, silastic, PVC, Dacron, and polyurethane. The poly(amido-amine) is able to complex with heparin by electrostatic interaction. The heparin-adsorbing capacity of the materials so obtained has been tested by biological tests. Heparin is only released at pH > 10, confirming the strong interaction between poly(amido-amine) and heparin. Preliminary theoretical studies have been made to construct a tentative model of the arrangement in the space of poly(amido-amine).     

Functionalization of poly(oxyethylene phosphonate) under phase-transfer catalyst conditions

The feasibility of the reaction of poly(oxyethylene phosphonate) 1 with chloroacetone under phase-transfer catalysis conditions for the preparation of poly(oxyethylene phosphonate)s bearing α-hydroxyl and oxirane groups in the side chains has been investigated. It has been established that the first stage of the reaction involves addition of the P-H to the carbonyl bond of chloroacetone resulting in poly(oxyethylene α-hydroxy phosphonate). During the second stage of the reaction, the oxirane formation proceeds via elimination of chloride ion. It is possible to direct the reaction to produce poly(oxyethylene phosphonate) 2, bearing 86.2% α-hydroxyl groups, or to poly(oxyethylene phosphonate) 3, bearing 91% oxirane groups. The structure of the products has been proved by means of ¹H, ¹³C and ³¹P NMR spectroscopy. Thus design poly(oxyethylene phosphonate)s bearing α-hydroxyl and oxirane groups are of interest as polymer-carriers of drugs and polymers with their own bioactivity. The cytotoxicity of poly(oxyethylene phosphonate), poly(oxyethylene phosphonate)s bearing α-hydroxyl and oxirane groups has been studied.     

Synthesis,physico-chemical properties and biomedical applications of poly(amidoamine)s

The aim of this article is to provide a comprehensive survey on synthesis, chemical and physico-chemical properties, and applications in several fields, including the biomedical field, of a family of tertiary amino polymers, the poly(amido-amine)s.     

Ring‐opening bulk polymerization of five‐ and six‐membered cyclic phosphonates using maghnite,a nontoxic proton exchanged montmorillonite clay

A new method of preparation of poly(alkylene H‐phosphonate)s by ring‐opening bulk polymerization of the five‐ and six‐membered cyclic phosphonates monomers using the nontoxic Maghnite‐H⁺ as the initiator is described. Cyclic phosphonate monomers have been first synthesized. In particular, a new one‐step synthesis of 2‐hydro‐2‐oxo‐1,3,2‐dioxaphospholane is reported with a yield of 70%. The efficiency of the montmorillonite sheet silicate clay which exchanged with protons, called Maghnite‐H⁺, as cationic initiator has been proved and the resulting biomimetic poly(alkylene H‐phosphonate)s have been characterized. The Maghnite‐H⁺ regenerated after one turn‐over has showed to be still efficient as initiator for the ring‐opening polymerization. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Poly(ester)s containing germanium and silicon in the main chain,part 2: Static and dynamics behavior of monolayers at the air–water interface

The static and dynamic behavior of the Langmuir monolayers of poly(ester)s containing germanium and silicon in the main chain (Scheme 1 ) is reported. True monolayers are found for all the poly(ester)s studied. The isotherms of surface pressure versus surface area for poly(ester)s exhibit a behavior of the expanded‐type monolayers and that of condensed‐type monolayers. It was observed that the addition of an hydrophilic polymer such as poly(monomethyl itaconate) to the water subphase produces significant changes in the isotherm properties. The interfacial rheology of the poly(ester)s monolayers has also been studied by using Oscillatory Barrier Experiments in a low‐frequency range. It was found that the elasticity and the dilational viscosity increase from diluted monolayers until a surface concentration about 20 × 10⁻⁵ mg cm⁻². The static and dynamic elasticities were found to be very similar for the poly(ester)s over the dilute range. It was possible to conclude that these poly(ester)s form extremely viscoelastic monolayers. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

New comb-like poly(n-alkyl itaconate)s with crystalizable side chains

A series of poly(mono n-alkyl itaconate)s, poly(methyl n-alkyl itaconate)s and poly(di n-alkyl itaconate)s with n=12, 14, 16, 18 and 22 have been prepared by radical polymerization. NMR studies point out that poly(methyl n-alkyl itaconate)s and poly(di n-alkyl itaconate)s are mainly syndiotactic polymers whereas poly(mono n-alkyl itaconate)s are obtained as almost atactic polymers. The characterization performed by DSC, solid state ¹³C CP/MAS NMR and X-ray diffraction, indicates that the side chains of poly(mono n-alkyl itaconate)s and poly(methyl n-alkyl itaconate)s derivatives with more than 12 carbon atoms are able to crystallize in hexagonal lattices. In the case of poly(di n-alkyl itaconate)s, when the side chains contain 12 or more carbon atoms, they are able to crystallize also in hexagonal lattices.     

Complexation of poly(vinylpyrrolidone) and gelatin with some transition metal chlorides in aqueous solution

Complexation of poly(vinylpyrrolidone) and gelatin with certain metal chlorides (HgCl₂, CdCl₂, CoCl₂, and ZnCl₂) have been investigated by viscosimetric and spectrophotometric techniques in aqueous solutions. While the change in intrinsic viscosity, [η], of poly(vinylpyrrolidone) has shown a discontinuity with a concentration of metal chlorides, gelatin showed a steady decrease with increasing metal chloride concentration. The decreasing order of effectiveness of cations in complex formation is Hg²⁺ > Cd²⁺ > Co²⁺ > Zn²⁺ for poly(vinylpyrrolidone) and Zn²⁺ > Co²⁺ > Cd²⁺ > Hg²⁺ for gelatin solutions. It has been suggested that the poly(vinylpyrrolidone)/metal cation interaction is a charge-controlled reaction, and gelatin/metal cation is a covalent coordination in character. A similar metal cation effect has been observed for poly(vinylpyrrolidone) by UV-VIS spectrophotometry. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 891–895, 1998     

The effect of segment length on some properties of thermoplastic poly(ester–siloxane)s

A series of novel thermoplastic elastomers, based on poly(dimethylsiloxane) (PDMS) as the soft segment and poly(butylene terephthalate) (PBT) as the hard segment, were synthesized by catalyzed two‐step, melt transesterification reactions of dimethyl terephthalate and methyl esters of carboxypropyl‐terminated poly(dimethylsiloxane)s (M?_n = 550–2170 g mol^?1) with 1,4‐butanediol. The lengths of both the hard and soft segments were varied while the weight ratio of the hard to soft segments in the reaction mixture was maintained constant (57/43). The molecular structure, composition and molecular weights of the poly(ester–siloxane)s were examined by ¹H NMR spectroscopy. The effectiveness of the incorporation of the methyl‐ester‐terminated poly(dimethylsiloxane)s into the copolymer chains was verified by chloroform extraction. The effect of the segment length on the transition temperatures (T_m and T_g) and the thermal and thermo‐oxidative degradation stability, as well as the degree of crystallinity and hardness properties of the synthesized TPESs, were studied. Copyright © 2003 Society of Chemical Industry     

Synthesis and characterization of a poly(ether–ester) copolymer from poly(2,6 dimethyl‐1,4‐phenylene oxide) and poly(ethylene terephthalate)

A series of poly(ether–ester) copolymers were synthesized from poly(2,6 dimethyl‐1,4‐phenylene oxide) (PPO) and poly(ethylene terephthalate) (PET). The synthesis was carried out by two‐step solution polymerization process. PET oligomers were synthesized via glycolysis and subsequently used in the copolymerization reaction. FTIR spectroscopy analysis shows the coexistence of spectral contributions of PPO and PET on the spectra of their ether–ester copolymers. The composition of the poly(ether–ester)s was calculated via ¹H NMR spectroscopy. A single glass transition temperature was detected for all synthesized poly(ether–ester)s. T_g behavior as a function of poly(ether–ester) composition is well represented by the Gordon‐Taylor equation. The molar masses of the copolymers synthesized were calculated by viscosimetry. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006     

Crystallization and solid‐state polymerization of poly(aryl ester)s

The crystallization and solid‐state polymerization (SSP) of poly(aryl ester)s was investigated. Oligomers with different end‐groups were prepared by degradation of commercially available poly(aryl ester)s. The SSP of these oligomers was carried out after crystallization and under reduced pressure, in the presence of various catalysts. Polymers were characterized by means of their inherent viscosities and thermal properties. It has been found that Ti(OⁱPr)₄ was a better catalyst for SSP. The structures and morphologies of semicrystalline poly(aryl ester)s were investigated by X‐ray diffraction and differential scanning calorimetry (DSC). Copyright © 2004 Society of Chemical Industry     

Synthesis of poly(ether amide)s from p‐xylylene glycol and bis(ether nitrile)s

BACKGROUND: Poly(ether amide)s have been well studied in terms of improving the physical and thermal properties of aromatic polyamides. Poly(ether amide)s of high enough molecular weight to be useful for industrial purposes are generally difficult to prepare. The objective of this project was to introduce a simple and commercially feasible process to prepare poly(ether amide)s by a polymerization reaction at relatively low temperature. RESULTS: A series of poly(ether amide)s were prepared by direct polyamidation of p‐xylylene glycol with bis(ether nitrile)s via the Ritter reaction using concentrated H₂SO₄ in acetic acid. The synthesized poly(ether amide)s showed good solubility in polar aprotic solvents. The resultant poly(ether amide)s had inherent viscosities in the range 0.36–1.03 dL g^?1. The glass transition temperatures of the poly(ether amide)s were determined using differential scanning calorimetry to be in the range 190–258 °C. Thermogravimetric analysis data for these polymers indicated the 10% weight loss temperatures to be in the range 290–390 °C in nitrogen atmosphere. CONCLUSION: The Ritter reaction was applied for the synthesis of a variety of poly(ether amide)s with moderate to high molecular weights. This procedure provides a simple polymerization process for the convenient preparation of poly(ether amide)s in high yield at room temperature. Copyright © 2009 Society of Chemical Industry     

Thermal behaviour of films of partially neutralized poly(acrylic acid). 2: The influence of univalent cations

Further studies have been carried out on the thermal behaviour of partially neutralized poly(acrylic acid), using ammonium or sodium ions as the neutralizing species. It was found that, unlike the partial poly(acrylates) of lithium, sodium or potassium, partially neutralized ammonium poly(acrylate) did not undergo thermal decarboxylation on heating to 250°C. Instead, the anhydride groups, formed by reaction of the unneutralized portions of the poly(acrylic acid) macromolecule, underwent no further reaction. On the other hand, further study of the decarboxylation of 10% neutralized sodium poly(acrylate) has shown the process to be first-order in anhydride groups, with a rate constant of 2 23 × 10-³ s^?1 at 250×C. A mechanism consistent with the kinetic data is proposed to account for the overall sequence leading to decarboxylation.     

Synthesis and properties of poly(arylene ether)s based on 3‐pentadecyl 4,4'‐biphenol

A new biphenol, 3‐pentadecyl 4,4′‐biphenol, was synthesized starting from 3‐pentadecylphenol and was polycondensed with 4,4′‐difluorobenzophenone, 1,3‐bis(4‐fluorobenzoyl)benzene and bis(4‐fluorophenyl)sulfone to obtain poly(arylene ether)s with biphenylene linkages in the backbone and pendent pentadecyl chains. Inherent viscosities and number‐average molecular weights (M_n) of the poly(arylene ether)s were in the range 0.50 ? 0.81 dL g^?1 and 2.2 × 10⁴ ? 8.3 × 10⁴, respectively. Detailed NMR spectroscopic studies of the poly(arylene ether)s indicated the presence of constitutional isomerism which existed because of the non‐symmetrical structure of 3‐pentadecyl 4,4′‐biphenol. The poly(arylene ether)s readily dissolved in common organic solvents such as dichloromethane, chloroform and tetrahydrofuran and could be cast into tough, transparent and flexible films from their chloroform solutions. The poly(arylene ether)s exhibited T_g values in the range 35–60 °C which are lower than that of reference poly(arylene ether)s without pentadecyl chains. The 10% decomposition temperatures (T₁₀) of the poly(arylene ether)s were in the range 410–455 °C indicating their good thermal stability. A gas permeation study of poly(ether sulfone) containing pendent pentadecyl chains revealed a moderate increase in permeability for helium, hydrogen and oxygen. However, there was a large increase in permeability for carbon dioxide which could be attributed to the internal plasticization effect of pendent pentadecyl chains. © 2016 Society of Chemical Industry     

Applied macroinorganics. II. Protonation and heavy metal ions complex-formation behavior of three crosslinked resins of poly(amido-amine) structure

Three resins having a poly(amido-amine) structure have been synthesized. The basicity and complexing ability towards copper(II) have been investigated by potentiometric techniques, and compared with those of the corresponding soluble polymers. The adsorbing capacities of the resins in columns were tested, and a sharp separation between different metal ions is achieved.     

Synthesis of novel optically active poly(ester‐imide)s with benzophenone linkages by microwave‐assisted polycondensation

A new simple and rapid polycondensation reaction of 4,4′‐carbonyl‐bis(phthaloyl‐L ‐alanine)diacid chloride [N,N ′‐(4,4′‐carbonyldiphthaloyl)]bisalanine diacid chloride with several diphenols, such as bisphenol‐A, phenolphthalein, 1,8‐dihydroxyanthraquinone, 4,4′‐dihydroxybiphenyl, 1,5‐dihydroxynaphthalene and hydroquinone, in the presence of a small amount of a polar organic medium such as o‐cresol was performed using a domestic microwave oven. The polycondensation reaction proceeded rapidly and was almost complete within 12 min to give a series of poly(ester‐imide)s with inherent viscosities of about 0.35–0.58 dl g⁻¹. The resulting poly(ester‐imide)s were obtained in high yield and are optically active and thermally stable. All the above compounds have been fully characterized by IR spectroscopy, elemental analysis, inherent viscosity (η_inh), solubility test and specific rotation. Thermal properties of the poly(ester‐imide)s have been investigated using thermal gravimetric analysis (TGA). © 2000 Society of Chemical Industry     

Synthesis and characterization of hyperbranched aromatic poly(ester-imide)s

The synthesis and characterization of hyperbranched aromatic poly(ester-imide)s are described. A variety of AB₂ monomers, N-[3- or 4-bis(4-acetoxyphenyl)toluoyl]-4-carboxyl-phthalimide and N-{3- or 4-[1,1-bis(4-acetooxyphenyl)]ethylphenyl}-4-carboxy phthalimides were prepared starting from condensation of nitrobenzaldehydes or nitroacetophenones with phenol and used for synthesis of hyperbranched poly(ester-imide)s containing terminal acetyl groups by transesterification reaction. These hyperbranched poly(ester-imide)s were produced with weight-average molecular weight of up to 6.87 g/mol. Analysis of ¹H NMR and ¹³C NMR spectroscopy revealed the structure of the four hyperbranched poly(ester-imide)s. These hyperbranched poly(ester-imide)s exhibited excellent solubility in a variety of solvents such as N,N-dimethylacetamide, dimethyl sulfoxide, and tetrahydrofuran and showed glass-transition temperatures between 217 and 255 °C. The thermogravimetric analytic measurement revealed the decomposition temperature at 10% weight-loss temperature (T_d¹⁰) ranging from 365 to 416 °C in nitrogen.     

The Mannich bases in polymer synthesis: 3. Reduction of poly(β-aminoketone)s to poly(γ-aminoalcohol)s and their N-alkylation to poly(γ-hydroxy quaternary ammonium salt)s

Several poly(β-aminoketone)s, obtained by polyconensation of bis Mannich bases with bis (secondaryamine)s, have been quantitatively reduced to poly(γ-aminoalcohol)s. The stereochemistry of these polymers, as well as that of the reduction products of the parent bis Mannich bases has been investigated. By N-alkylation of the same polymers, poly(γ-hydroxy quaternary ammonium salt)s have been also prepared.     

Design of novel poly(methyl vinyl ether) containing AB and ABC block copolymers by the dual initiator strategy

A new set of block copolymers containing poly(methyl vinyl ether) (PMVE) on one hand and poly(tert-butyl acrylate), poly(acrylic acid), poly(methyl acrylate) or polystyrene on the other hand, have been prepared by the use of a novel dual initiator 2-bromo-(3,3-diethoxy-propyl)-2-methylpropanoate. The dual initiator has been applied in a sequential process to prepare well-defined block copolymers of poly(methyl vinyl ether) (PMVE) and hydrolizable poly(tert-butyl acrylate) (PtBA), poly(methyl acrylate) (PMA) or polystyrene (PS) by living cationic polymerization and atom transfer radical polymerization (ATRP), respectively. In a first step, the Br and acetal end groups of the dual initiator have been used to generate well-defined homopolymers by ATRP (resulting in polymers with remaining acetal function) and living cationic polymerization (PMVE with pendant Br end group), respectively. In a second step, those acetal functionalized polymers and PMVE-Br homopolymers have been used as macroinitiators for the preparation of PMVE-containing block copolymers. After hydrolysis of the tert-butyl groups in the PMVE-b-ptBA block copolymer, PMVE-b-poly(acrylic acid) (PMVE-b-PAA) is obtained. Chain extension of the AB diblock copolymers by ATRP gives rise to ABC triblock copolymers. The polymers have been characterized by MALDI-TOF, GPC and ¹H NMR.     

Low molecular weight polyacrylic acid with pendant aminomethylene phosphonic acid groups

Low molecular weight poly(acrylic acid‐co‐vinyl aminomethylene phosphonic acid)s were prepared by consecutively applying the Hofmann degradation and the Mannich reaction to polyacrylamide and poly(acrylamide‐co‐acrylic acid)s. ¹H‐NMR, ³¹P‐NMR, and microanalysis were used for structural analyses. These polymers were tested as anti‐scalent and they showed better anti‐scalent effect than commercial poly(acrylic acid)s. The scale inhibition properties of copolymers increased with increasing amount of aminomethylene phosphonic acid groups. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 870–874, 2000