Study on a novel polyimide precursor prepared by a modified polymerization of monomeric reactants (MPMR) procedure

Chu, Qinghui; Zhang, Jin; Xu, Zhengyan; Ding, Mengxian

doi:10.1002/(sici)1521-3935(20000301)201:5<505::aid-macp505>3.0.co;2-i

Cited by 2 publications

(1 citation statement)

References 8 publications

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“…Polyimides form a well‐known class of polymer materials with excellent thermal behavior and mechanical properties and very good chemical resistance and electrical properties. Because of these outstanding properties, polyimides have found extensive applications as fibers,1–4 films,5–8 coatings,9–11 photoresists,12–15 and composites,16–20 for many years. Ultra‐thin polyimide fibers can be made with nanometer scale diameters by means of electrospinning 21–23.…”

Section: Introductionmentioning

confidence: 99%

High‐strength and high‐toughness polyimide nanofibers: Synthesis and characterization

Cheng

Chen

et al. 2010

J of Applied Polymer Sci

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High-strength and high-toughness nanofibers were made from polyimide 6F-PI through electrospinning. The 6F-PI had a backbone made up with 3,3 0 ,4, 4 0 -biphenyl-tetracarboxylic dianhydride and 2,2-bis[4-(4-aminophenoxy)phenyl]-hexafluoro-propane residues. Electrospun 6F-PI precursor nanofibers were collected in the form of aligned fiber sheet on the rim of a rotating disc. Heating process converted the precursor fiber sheets to 6F-PI nanofiber sheets. Gel permeation chromatography and Ostwald Viscometer were used to determine the molecular weight and the molecular weight distribution of the 6F-PI precursor, i.e., the 6F-polyamic acid. Scanning electron microscopy, infrared spectroscopy, X-ray scattering, tensile testing, dynamic mechanical analysis, thermogravimetric analysis, and differential scanning calorimetry were employed to characterize the surface morphology, thermal stability, and mechanical properties of the 6F-PI nanofiber sheets. Experimental results show that the nanofibers were well aligned in the sheets with fiber diameters ranging from 50 to 300 nm. The nanofiber sheets were stable to over 450 C, with a glass transition at 265.2 C. The uniaxial tension test showed that the 6F-PI nanofiber sheets had superior mechanical properties. The ultimate tensile strength, modulus, toughness, and elongation to break of the 6F-PI nanofiber sheets are respectively, 308 6 14 MPa, 2.08 6 0.25 GPa, 365 6 20 MPa, and 202 6 7%. It is expected that electrospun PI nanofibers with such high toughness and high ultimate tensile strength can find applications in high-performance textiles and composites, for example.

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Section: Introductionmentioning

confidence: 99%

High‐strength and high‐toughness polyimide nanofibers: Synthesis and characterization

Cheng

Chen

et al. 2010

J of Applied Polymer Sci

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A Novel Zirconium Modified Arylacetylene Resin: Preparation, Thermal Properties and Ceramifiable Mechanism

Mei

Wang

et al. 2020

Polymers

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With the rapid development of thermal protection systems for the aerospace industry and power electronics, polyarylacetylene (PAA) resin plays an important role because of its good mechanical properties, high glass transition temperature (T g ), low water absorption, high char yield (Y c ), and the fact that there is no byproduct released in the curing process. In order to further improve the thermal property of PAA based FRP for the thermal protection field, the introduction of a zirconium element into arylacetylene is promising. In this paper, zirconium modified arylacetylene (ZAA) resin was prepared by two-step synthesis. The FTIR analysis characterized its molecular structure and confirmed the products. The viscosity of ZAA was about 6.5 Pa·s when the temperature was above 120 • C. The DSC analysis showed that the ZAA had a low curing temperature, and its apparent activation energy was 103.86 kJ/mol in the Kissinger method and 106.46 kJ/mol in the Ozawa method. The dielectric constant at 1 MHz of poly(zirconium modified arylacetylene) (PZAA) was 3.4. The TG analysis showed that the temperatures of a weight loss of 5% (T d5 ) and char yield (Y c ) at 800 • C of PZAA were 407.5 • C and 61.4%, respectively. The XRD results showed the presence of SiO 2 and ZrO 2 in the PZAA residue after ablation. The XRF results showed that the contents of SiO 2 and ZrO 2 in PZAA residual after ablation were, respectively, 15.3% and 12.4%. The SEM showed that the surface of PZAA after ablation had been covered with a dense and rigid ceramic phase composed of ZrO 2 and SiO 2 . Therefore, the introduction of Zr into arylacetylene greatly improved the densification of the surface after ablation, and improved the heat resistant property.

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Study on a novel polyimide precursor prepared by a modified polymerization of monomeric reactants (MPMR) procedure

Cited by 2 publications

References 8 publications

High‐strength and high‐toughness polyimide nanofibers: Synthesis and characterization

High‐strength and high‐toughness polyimide nanofibers: Synthesis and characterization

A Novel Zirconium Modified Arylacetylene Resin: Preparation, Thermal Properties and Ceramifiable Mechanism

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