Polyamory Research Articles

Synthesis of new poly(amide-imide)s XX. Preparation and properties of poly(amide-Imide)s derived from 1,7-Bis(4-aminophenoxy) naphthalene, trimellitic anhydride, and various aromatic diamines

A dicarboxylic acid (1,7-BTMPN) bearing two preformed imide rings, was prepared from the condensation of 1,7-bis(4-aminophenoxy)naphthalene and trimellitic anhydride. A new family of poly(amide-imide)s with inherent viscosities up to 1.56 dL/g (0.5g/dL in DMAc at 30 °C) was prepared by the triphenyl phosphite activated polycondensation from the diimide-diacid 1,7-BTMPN with various aromatic diamines in a medium consisting ofN-methyl-2-pyrrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers were readily soluble in polar solvents such as NMP and DMAc. All the soluble poly(amide-imide)s can form transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 185–267°C and the 10% weight loss temperatures were above 430 °C in nitrogen.

Solubility of Polymers and Copolymers in Supercritical CO2

Cloud-point data to temperatures of 270 °C and 3000 bar are presented for CO2 with the family of poly(acrylates) including methyl, ethyl, propyl, butyl, ethylhexyl, and octadecyl, with poly(butyl methacrylate), with poly(vinyl acetate), with statistically random copolymers of poly(ethylene-co-methyl acrylate) with 41, 31, and 18 mol % acrylate, with poly(tetrafluoroethylene-co-hexafluoropropylene) and poly(vinylidene-co-hexafluoropropylene) copolymers, each with ∼20 mol % hexafluoropropylene, and with Teflon AF. Over the same range of conditions, CO2 cannot dissolve polyethylene, poly(acrylic acid), poly(methyl methacrylate), poly(ethyl methacrylate), polystyrene, poly(vinyl fluoride), or poly(vinylidene fluoride). CO2 is a weak solvent that exhibits the temperature-sensitive characteristics observed with polar solvents. The solubility of a nonpolar hydrocarbon polymer or a copolymer in CO2 can be increased by at least partially fluorinating the polymer or by incorporating some polar groups into the backbone architecture of the polymer. Because it is such a weak solvent, CO2 can distinguish differences in polymer architecture even for polymers from the same chemical family, which means that polymer free volume plays a role in determining solubility.

Padé approximations in noise filtering

We first recall the results on the distribution of poles and zeros of Padé approximations to noisy Taylor series around a point. We then report the numerical experiment on noisy data coming from inelastic electron-scattering cross-sections on rare gases, as functions of the momentum transfer at fixed energy. We apply the Thiele algorithm (Padé approximations of type II) to those data, which are known to belong to an analytic function in a cut plane from −∞ to 0. In this case, the poles and zeros split into three families: (i) Doublet pole-zero at a distance of the order of the computer roundoff. (ii) Doublet pole-zero at a distance of the order of the noise in the experimental data. (iii) Remaining poles and zeros compatible with the analytic structure of the experimentally measured function. By throwing away the first two families of poles and zeros (noisy ones), we were able to obtain an excellent filtering of the data compatible with the analytic structure of the analyzed function.

New poly(amide–imide)s syntheses. 17. Preparation and properties of poly(amide–imide)s derived from N‐phenyl‐3,3‐bis[4‐(4‐aminophenoxy)‐phenyl]phthalimidine, trimellitic anhydride, and various aromatic diamines

AbstractA dicarboxylic acid (1) bearing two phthalimide rings was prepared by the condensation of N‐phenyl‐3,3‐bis[4‐(4‐aminophenoxy)phenyl]phthalimidine and trimellitic anhydride. A new family of poly(amide–imide)s having inherent viscosities of 0.65–1.65 dl/g was prepared by the triphenyl phosphite activated polycondensation of the diimide–diacid 1 with various aromatic diamines in a medium consisting of N‐methyl‐2‐pyrrolidone (NMP), pyridine, and calcium chloride. All the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N‐dimethylacetamide. The soluble poly(amide–imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range 249–340°C and the 10% weight loss temperatures were above 545°C in nitrogen.

New poly(amide‐imide) syntheses. XII. Preparation and properties of poly(amide‐imide)s based on the diimide‐diacid condensed from 9,9‐bis[4‐(4‐aminophenoxy)phenyl] fluorene and trimellitic anhydride

AbstractA dicarboxylic acid (I) was prepared from the condensation of 9,9‐bis[4‐(4‐aminophenoxy) phenyl] fluorene and trimellitic anhydride. A new family of poly(amide‐imide)s having inherent viscosities of 0.75‐1.04 dL/g was prepared by the triphenyl phosphite activated polycondensation from the diimide‐diacid I with various aromatic diamines in a medium consisting of N‐methyl‐2‐pyrrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N‐dimethylacetamide. All the soluble poly(amide‐imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these polymers were in the range of 262–325°C and the 10% weight loss temperatures were above 525°C in air. © 1994 John Wiley & Sons, Inc.

New poly(amide‐imide) syntheses. V. Preparation and properties of poly(amide‐imide)s based on the diimide—diacid condensed from 2,2‐bis[4‐(4‐aminophenoxy)phenyl]propane and trimellitic anhydride

AbstractA dicarboxylic acid (1) bearing two pre‐formed imide rings, was prepared from the condensation of 2,2‐bis[4‐(4‐aminophenoxy)phenyl]propane and trimellitic anhydride. A new family of poly(amide‐imide)s having inherent viscosities of 0.53–1.68 dL/g was prepared by the triphenyl phosphite activated polycondensation from the diimide—diacid I with various aromatic diamines in a medium consisting of N‐methyl‐2‐pyrolidone (NMP), pyridine, and calcium chloride. Most of the resulting polymers showed an amorphous nature and were readily soluble in polar solvents such as NMP and N,N‐dimethylacetamide. All the soluble poly(amide‐imide)s afforded transparent, flexible, and tough films. The glass transition temperatures of these poly(amide‐imide)s were in the range of 237–293°C and the 10% weight loss temperatures were above 508°C in nitrogen. © 1993 John Wiley & Sons, Inc.

Synthesis and characterization of a new biodegradable semi-solid poly(ortho ester) for drug delivery systems

Since the late 1970s, three families of poly(ortho esters) (POE) were synthesized to provide bioerodible carriers for drug delivery devices. The most recent POE is a semi-solid polymer with a viscous behavior at room temperature. Polymer synthesis by a transesterification reaction between a triol and a trialkyl ortho ester is described. The structure of the polymer was confirmed by conventional methods such as 1H-NMR, 13C-NMR and FT-IR. Information concerning average molecular weight and intrinsic viscosity was obtained respectively by GPC and viscosimetry. Residual solvents in the polymer were determined using gas chromatography. The chromatographic conditions were optimized to enable the quantification of the solvents in concentrations of a few percent. The mechanical behavior of the semi-solid POE was determined by rheometric measurements. Hydrolysis of the polymer leads to the formation of the original triol and the carboxylic acid derived from the trialkyl ortho ester used in the transesterification step. No toxicological problems associated with these compounds are anticipated.

Synthesis and characterization of a new family of poly(ortho esters)

A previously reported synthesis of ointment-like poly(ortho ester)s prepared from a flexible triol and an alkyl orthoacetate has been extended to the preparation of solid materials by replacing the flexible triol with a rigid triol. The hydrolysis products of the polymer have been determined, and the hydrolysis has been shown to proceed exclusively by cleavage of the exocyclic alkoxy group of the ortho ester linkage. The lowest alkyl analog is crystalline, but the higher alkyl analogs are amorphous. The polymer is hydrolytically labile, and the rate of hydrolysis increases as the pH of the erosion medium decreases

Synthesis of a new family of poly(amido‐amine)s carrying poly(oxyethylene) side chains

AbstractA new class of water‐soluble poly(amido‐amine)s (PAA's) carrying poly(oxyethylene) (PEO) side chains were synthesized following two distinct pathways. The first route consists in the direct stepgrowth polymerization through addition in water of an equimolar amount of α‐(2‐aminoethyl)‐ω‐methoxypoly(oxyethylene) (6) of well‐defined molecular weight to 1,4‐bis(acryloyl)‐piperazine (7). Furthermore, this reaction was performed in the presence of an excess of the bisacrylmonomer 7, resulting in a new bisacrylic macromonomer (9) of PEO. In the second route this bisadduc 9 was then polymerized with piperazine (10), yielding a PEO‐grafted PAA. The structures of both polymers were characterized by means of 1H NMR. Viscosity and vapour pressure osmometric measurements revealed that the molecular weights in both cases were fairly low (M̄n ≈ 3 000).

Recent developments in the synthesis and utilization of poly (ortho esters)

One family of poly (ortho esters) can be prepared by the reaction of diketene acetals and diols. This polymer has recently been used in the development of bioerodible implants for the release of the antineoplastic agent 5-fluorouracil (5-FU) and the narcotic antagonist naltrexone. Polymer erosion was found to depend on both the nature of the acidic excipient used to control erosion rate and on the composition of the polymer. Good control over rate of release of 5-FU was achieved by using suberic acid and a polymer based on 1,6-hexanediol. Preliminary encouraging survival times have been obtained with mice inoculated with IL1210 leukaemia. Polymers with a 50 wt% loading of naltrexone pamoate have been shown to release the drug by good zero order kinetics and in vivo studies are currently in progress. Another family of poly (ortho esters) can be prepared by a transesterification reaction between a triol and a trialkyl ortho ester. When the transesterification reaction is carried out with flexible triols such as 1,2,6-hexanetriol, ointment-like materials are obtained even though molecular weight can be in excess of 50,000. Release of therapeutic agents from such ointments can also be controlled with acidic excipients. Such materials are particularly useful for peptide release because these can be incorporated into the polymer at room temperature without the use of solvents. Preliminary indications of retention of activity have been obtained.

Dielectric relaxation behaviour of poly(mono-n-alkyl itaconates)

Dielectric relaxation measurements on a family of poly(mono-n-alkyl itaconates) have been performed. Two relaxation peaks have been observed within the temperature range studied. The first one at lower temperature (153 K at 1 kHz), which we call the γ peak and have attributed to motion in the lateral chains involving methylene sequences, depends on the length of the side-chain. The second relaxation labelled β (233 K at 1 kHz) is related mainly to motion of the lateral group. A peculiar behaviour has been observed in the case of poly(mono-tetradecyl itaconate). The results have been discussed in terms of the different possible motions of the side-chains.

Soluble and electroactive transition metal complex polymers

New soluble, electroactive metal complex polymers have been synthesized from bis-(4-styryldithiocarbonate)oxide and Ni, Cu, Pd, and Pt salts. Pressed pellet conductivities for the polymers are ca. 10 −6 Ω −1 cm −1. A family of poly(metal tetrathiooxalates), poly (MTTO), of NiII, CuII, and CuI have been synthesized and characterized. These compounds display typical semiconducting behavior having room temperature pressed pellet conductivities of ca. 10 0 – 10 1 Ω −1 cm −1. Structural data on the poly(MTTO)s has been obtained using the Large Angle X-ray Scattering technique (LAXS).

Macro-inorganics. Part 6. Protonation and complex formation of a new series of polymers whose repeating units behave independently

The protonation and copper(II) complex formation of some new polymers with a poly(amido-amine) structure has been studied in aqueous solution by potentiometric, calorimetric, and spectroscopic techniques. The polymers are characterized by the fact that no ring structures are present along the main chain between tertiary amino-groups of different units. The results indicate the monomeric units of this new family of poly(amido-amines) behave independently towards both protonation and complex formation. Comparison with previously studied poly(amido-amines) shows that the presence of linear diamide moieties in place of 1,4-diacylpiperazine rings [as in the previously studied poly(amido-amines)] has a slight influence on the protonation constants, although differences may be observed in the thermodynamic functions ΔH⊖ and ΔS⊖. Significant differences are observed in copper(II) complex formation.

Molecular Distributions at Equilibrium. IV. The New Family of Poly(chloroarsenous Methylimides)

Dissolution of the various amounts of the cage compound, As4(NCH3)6, in arsenic trichloride gives homogeneous liquids, the proton nuclear magnetic resonance (NMR) spectra of which show three major peaks. These resonances are attributed to methylimino bridges in (1) a pair of monofunctional units, (2) a pair consisting of a monofunctional and a difunctional unit, and (3) a pair of difunctional units where a unit of functionality i is part of a molecule and has the structure AsCl3—i[N(CH3)—]i/2. Large deviations from random scrambling of these structure-building units with respect to the formation in a ring-free system of the molecule consisting of two monofunctional units bonded together is interpreted primarily in terms of the presence of ring molecules.

Excange of Parts between Molecules at Equilibrium. IV. The New Family of Poly(fluoroarsenous methylimides)

Excange of Parts between Molecules at Equilibrium. IV. The New Family of Poly(fluoroarsenous methylimides)