Soluble aromatic polyimides and polyamides based on 4,4′-diaminotriphenylmethane (original) (raw)
Related papers
One‐step synthesis of aromatic polyimides based on 4,4′‐diaminotriphenylmethane
Journal of Applied Polymer Science, 1996
The feasibility of using a one-step high-temperature polycondensation for the synthesis of aromatic polyimides, based on 4,4'-diaminotriphenylmethane (DA-TPM), was studied. It was found that the reaction of DA-TPM with various aromatic dianhydrides in nitrobenzene at 180-200°C resulted in the formation of the high molecular weight soluble polyimides, PI-TPM. The reaction solutions cooled to ambient temperature were used for casting films. These PI-TPM films significantly exceeded their prototypes obtained by the thermal imidization of poly(amic acids) in terms of solubility and tensile properties. All studied polyimides demonstrated well-distinguished glass transition at 260-320OC. 0 1996
The Influence of Rigid and Flexible Monomers on the Physical-Chemical Properties of Polyimides
Journal of Applied Polymer Science, 2014
This article presents the synthesis and characterization of polyimides and copolyimides derived from rigid [4,40-(9-fluorenylidene)dianiline (FNDA) and 3,30,4,40-biphenyltetracarboxylic dianhydride (BPDA)] and flexible segments [4,40-(1,3-phenylenedioxy) dianiline (PDODA) and ethylenediaminetetraacetic dianhydride (EDTAn)], by polyaddition followed by thermal imidization of the polyamic acid. It describes the characterization of the polyimides and the polyamic acids in accordance to 1H NMR, FTIR, GPC, and XRD analysis, as well as solubility, mechanical (DMTA and stress–strain tests), thermal (DSC and TGA), and electric properties. Among the homopolymers, FNDA–BPDA and PDODA–BPDA form free-standing films. The first presents higher Tg, thermal stability and Young’s modulus. To tailor the properties copolyimides of FNDA, PDODA, and BPDA were synthesized. Young’s modulus, Tg, thermal stability, dielectric constant, and solubility progressively increase with increasing amount of FNDA.
Polymer Bulletin, 2010
A novel pyridine-containing aromatic diamine monomer, 4-phenyl-2,6bis[3-(4-aminophenoxy)phenyl]pyridine (m,p-PAPP), was successfully synthesized by a modified Chichibabin reaction of benzaldehyde and a substituted acetophenone, 3-(4-nitrophenoxy)acetophenone (m,p-NPAP), followed by a reduction of the resulting dinitro compound 4-phenyl-2,6-bis[3-(4-nitrophenoxy)phenyl]pyridine (m,p-PNPP) with Pd/C and hydrazine monohydrate. The aromatic diamine was employed to synthesize a series of pyridine-containing polyimides (PIs) by polycondensation with various aromatic dianhydrides in N,N-dimethylformamide (DMF) via the conventional two-step method, and further thermal or chemical imidization forming PIs. The inherent viscosities of the resulting poly(amic acid)s and PIs were 0.59-0.73 and 0.56-0.68 dL/g; most of the PIs obtained by chemical imidization were readily soluble in common organic solvents such as DMF, N,N-dimethylacetamide (DMAc), N-methyl-2-pyrrolidone (NMP), tetrahydrofuran (THF), etc. Meanwhile, strong and flexible PI films were obtained, which had good thermal stability, with the glass transition temperature (T g) of 204.5-237.4°C and the temperature at 10% weight loss of 527.7-552.0°C in nitrogen atmosphere, as well as outstanding mechanical properties with tensile strengths of 88.6-90.4 MPa, a tensile moduli of 1.04-1.56 GPa, and elongations at break of 7.2-8.7%. The PI films also were found to possess low water uptake of 0.89-0.98%.
Journal of Polymer Science Part A, 2000
A set of new aromatic polyamides were synthesized by the direct phosphorylation condensation of 4-(1-adamantyl)-1,3-bis-(4-aminophenoxy)benzene with various diacids. The polymers were produced with high yields and moderate to high inherent viscosities (0.43-1.03 dL/g), and the weight-average molecular weights and numberaverage molecular weights, determined by gel permeation chromatography, were in the range of 37,000-93,000 and 12,000-59,000, respectively. The polyamides were essentially amorphous and soluble in a variety of solvents such as N,N-dimethylacetamide (DMAc), cyclohexanone, and tetrahydrofuran. They showed glass-transition temperatures in the range of 240-300°C (differential scanning calorimetry) and 10% weightloss temperatures over 450°C, as revealed by thermogravimetric analysis in nitrogen. All the polymers gave strong films via casting from DMAc solutions, and these films exhibited good mechanical properties, with tensile strengths in the range of 77-92 MPa and tensile moduli between 1.5 and 2.5 GPa.
Polymer, 1999
A series of twelve aromatic diamines, 4,4 H -diamino-2,2 H -disubstitutedbiphenyls, has been designed and synthesized. These diamines were reacted with 2,2 H -bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) to form polyimides via a one-step polycondensation method. All of the resulting polyimides could be dissolved in common organic solvents and exhibited excellent film forming ability. At the same time, their inherent high thermal and thermo-oxidative stability of these polyimides was retained in the films. Because of the incorporation of disubstituted groups at the 2-and 2 H -positions of these biphenyl diamines, their crystallinity was suppressed to the level that they were in complete amorphous state. Further, the conjugation of the phenylene and imide groups in these polyimide films was interrupted, leading to clear blue shifts during light transmission. As this series of polyimides possessed the same backbone, the chain rigidity and linearity changed very little throughout the series. However, the molecular packing was affected by the introduction of different disubstituted pendant groups. Each polyimide film exhibited an a relaxation process related to the glass transition. This relaxation changed significantly with the size and the shape of the disubstituted pendant groups. In addition to this process, each of these polyimide films displayed a sub-glass transition, the b relaxation process, which was initiated by motion of the 4,4 H -diamino-2,2 H -disubstituted biphenyls. This study provided an opportunity to investigate how disubstituted pendant groups affected the a and b relaxation behaviors of these polyimides. With an increase of the sizes and the shape anisotropy of the disubstituted pendant groups at the 2-and 2 H -position, the nature of the motion regarding to the b relaxation was found to evolve from a non-cooperative process to a cooperative one, while the glass transition temperature (the a relaxation temperature) correspondingly decreased. ᭧
Synthesis and characterization of aromatic polyamides containing alkylphthalimido pendent groups
Journal of Polymer Science Part A, 2002
Polyarylates containing pendant silyl group were prepared by the phase-transfer catalyzed, two-phase polycondensations of 2,2-bis (4-hydroxypheny1)propane with corresponding dicarbonyl chlorides such as 2-trimethylsilylterephthaloyl chloride, 5-trimethylsilylisophthaloyl chloride, 5-dimethylphenylsilylisophthaloyl chloride, and B-triphenylsilylisophthaloyl chloride. The resulting amorphous polyarylates with glass transition temperatures of 163-214°C had inherent viscosities in the range of 0.41-0.95 dL/g. These polyarylates were readily soluble in common chlorinated hydrocarbons and it was possible to obtain transparent, flexible, and tough films from the polymer solutions. The prepared polyarylates showed fairly good thermal stabilities as well as tensile strengths, i.e., the tensile strengths of the cast films from chloroform solution were 6.0-6.7 kg/mm2. And TGA data revealed 10% weight losses and residual weights at 800°C were 437-495°C and 27-40% under nitrogen atmosphere, respectively.
European Polymer Journal, 2005
A new tetraimide-dicarboxylic acid (TIDA) I was synthesized starting from 3-aminobenzoic acid (m-ABA), 4,4 0-oxydiphthalic anhydride (ODPA), and 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene (BAFPB) at a 2:2:1 molar ratio in N-methyl-2-pyrrolidone (NMP). A series of organosoluble, light-colored poly(amide-imide-imide)s (PAII, III a-j) was prepared by triphenyl phosphite-activated polycondensation from the tetraimide-diacid I with various aromatic diamines (II a-j). All the polymers were readily soluble in a variety of organic solvents such as NMP, N,N-dimethyl acetamide (DMAc), dimethyl sulfoxide, and even in less polar m-cresol and pyridine. Polymer films cast from DMAc had the cutoff wavelengths between 374 and 384 nm and had the b * values in the range of 14.8-30.2. Polymers III a-j afforded tough, transparent, and flexible films, which had tensile strengths ranging from 87 to 103 MPa, elongations at break from 11% to 37%, and initial moduli from 1.9 to 2.3 GPa. The glass transition temperatures of these polymers were in the range of 242-274°C. They had 10% weight loss temperature above 526°C and showed the char yield more than 55% residue at 800°C in nitrogen.
Journal of Polymer Science Part A: Polymer Chemistry, 1995
4,4-(2,7-Naphthalenedioxy)dibenzoic acid, a new aromatic dicarboxylic acid monomer, was prepared starting from 2,7-dihydroxynaphthalene and p-fluorobenzonitrile in three steps. Using triphenyl phosphite (TPP) and pyridine as condensing agents, a series of novel aromatic polyamides were synthesized by the direct polycondensation of the diacid monomer and aromatic diamines in N-methyl-2-pyrrolidone (NMP) solution containing dissolved calcium chloride. The resulting polyamides had inherent viscosities ranging from 0.48 to 0.67 dL/g. Most of these polyamides were readily soluble in polar solvents, such as NMP and N,N-dimethylacetamide (DMAc). Transparent, flexible, and tough films were cast from their DMAc solutions. They had tensile strengths of 65-70 MPa, elongations to break of 5-7%, and initial moduli of 1.4-1.6 GPa. Most of these polymers proved to be amorphous, with glass transition temperatures in the range between 143-227ЊC. Thermogravimetric analysis (TG) showed that all the polyamides were stable up to 450ЊC in both air and nitrogen atmospheres.
Synthesis and Study of Thermo Stability Properties of Novel Polyamides
Journal of Environmental Analytical Chemistry, 2018
Aromatic and aliphatic diamines are one of the main components in polyamides, polyimides, polyurea and polyurethanes. To prepare high performance and well featured materials, attempts is directed to the novel diamine synthesis routes in which soluble thermo-resistant, soluble and easy process polymers are obtained. To solubility improvement and decreasing the glass transition temperature, existing flexible bonds in polymer repeating unit are necessary. These bonds decrease the internal rotational energies. Using heterocyclic rings or introducing of polar functional groups such as amide in the main synthetic polymer chain results in convenient polarity and solubility of polymer. Until now, massive investigations have been conducted to prepare aromatic monomers with high solubility and processing capabilities. In the current study, our main aim is to prepare diamines which are applicable in thermo-resistant polymers including polyamide, polyimide, polyurea and polyurethanes.