The effects of long and bulky aromatic pendent groups with flexible linkages on the thermal, mechanical and electrical properties of the polyimides and their nanocomposites with functionalized silica

Tharakan, Simi Annie; Sarojadevi, M.

doi:10.1039/d0ra08561h

Cited by 10 publications

(3 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…After the above discussion, it is evident that the modified Si–PI films display lower thermal stability compared with OH–PI films, , which can be explained by the reduced intermolecular attraction forces (e.g., hydrogen bonding) in Si–PI chain and the increased free volume associated with the TBDPS groups. However, these modified Si–PI films still possess comparatively high thermal stabilities, as well as high transparency and fluorescence, low k , and high solubility in both polar and nonpolar solvents, which are much better than those of the aromatic PI containing bulky side groups reported in the literature. − The multifunctional Si–PI films with excellent combined properties are suitable for wide applications in optical and microelectronic devices.…”

Section: Resultsmentioning

confidence: 99%

Simultaneously Improving the Optical, Dielectric, and Solubility Properties of Fluorene-Based Polyimide with Silyl Ether Side Groups

Liu

Zhao

2022

ACS Omega

View full text Add to dashboard Cite

Three fluorene-based polyimides with silyl ether groups (Si–PIs) were successfully synthesized by a simple and efficient silicon etherification reaction of hydroxyl-containing polyimides (OH–PIs) and tert -butylchlorodiphenylsilane (TBDPSCl), and their structures were confirmed by 1 H NMR and IR spectra. The bulky nonpolar tert -butyldiphenylsilyl (TBDPS) side groups in the modified PI unit instead of the strong electron donor −OH group is conducive to decreasing electronic conjugation and charge transfer (CT) interaction along the PI chain. Accordingly, the optical, dielectric, and solubility properties of the modified Si–PI films are simultaneously improved compared with the precursor OH–PI films. The modified Si–PI films demonstrate a meaningful enhancement in the transmittances at a wavelength of 400 nm ( T 400 ) to 74–81% from 42 to 55% of OH–PI films and the regeneration of fluorescence characteristics. The dielectric constant and loss of Si–PI films are also obviously reduced to 2.63–2.75 and 0.0024–0.0091 at 1 kHz from 4.19 to 4.78 and 0.0173–0.0295 of OH–PI films, respectively, due to substituted with the bulky nonpolar TBDPS groups to increase the free volume and hydrophobicity of Si–PI films. The solubility of Si–PIs in low- or nonpolar solvents (such as CHCl 3 , CH 2 Cl 2 , acetone, and toluene) is significantly improved. Furthermore, Si–PI films still maintain relatively good thermal properties with the 5% weight loss temperature ( T 5% ) in the range 470–491 °C under a nitrogen atmosphere and the glass transition temperature ( T g ) in the range 245–308 °C.

show abstract

Section: Resultsmentioning

confidence: 99%

Simultaneously Improving the Optical, Dielectric, and Solubility Properties of Fluorene-Based Polyimide with Silyl Ether Side Groups

Liu

Zhao

2022

ACS Omega

View full text Add to dashboard Cite

show abstract

“…Tharakan et al developed two novel flexible polyimides by reacting a new diamine containing two long/bulky aromatic pendant chains and flexible linkages, with tetra carboxylic acid dianhydrides [ 56 ]. In particular, aromatic dianhydrides such as 3,3′,4,4′-benzophenone tetra carboxylic acid dianhydride (BTDA) and 4,4′-(4,4′-isopropylidenediphenoxy) diphthalic anhydride (BPADA) were used to incorporate isopropylidene and keto groups into the polymer backbone.…”

Section: Thermal Stability Of Polyimide-based Materials For Space App...mentioning

confidence: 99%

A Comprehensive Review on the Thermal Stability Assessment of Polymers and Composites for Aeronautics and Space Applications

Barra,

Guadagno,

Raimondo

et al. 2023

Polymers

View full text Add to dashboard Cite

This review article provides an exhaustive survey on experimental investigations regarding the thermal stability assessment of polymers and polymer-based composites intended for applications in the aeronautical and space fields. This review aims to: (1) come up with a systematic and critical overview of the state-of-the-art knowledge and research on the thermal stability of various polymers and composites, such as polyimides, epoxy composites, and carbon-filled composites; (2) identify the key factors, mechanisms, methods, and challenges that affect the thermal stability of polymers and composites, such as the temperature, radiation, oxygen, and degradation; (3) highlight the current and potential applications, benefits, limitations, and opportunities of polymers and composites with high thermal stability, such as thermal control, structural reinforcement, protection, and energy conversion; (4) give a glimpse of future research directions by providing indications for improving the thermal stability of polymers and composites, such as novel materials, hybrid composites, smart materials, and advanced processing methods. In this context, thermal analysis plays a crucial role in the development of polyimide-based materials for the radiation shielding of space solar cells or spacecraft components. The main strategies that have been explored to improve the processability, optical transparency, and radiation resistance of polyimide-based materials without compromising their thermal stability are highlighted. The combination of different types of polyimides, such as linear and hyperbranched, as well as the incorporation of bulky pendant groups, are reported as routes for improving the mechanical behavior and optical transparency while retaining the thermal stability and radiation shielding properties. Furthermore, the thermal stability of polymer/carbon nanocomposites is discussed with particular reference to the role of the filler in radiation monitoring systems and electromagnetic interference shielding in the space environment. Finally, the thermal stability of epoxy-based composites and how it is influenced by the type and content of epoxy resin, curing agent, degree of cross-linking, and the addition of fillers or modifiers are critically reviewed. Some studies have reported that incorporating mesoporous silica micro-filler or microencapsulated phase change materials (MPCM) into epoxy resin can enhance its thermal stability and mechanical properties. The mesoporous silica composite exhibited the highest glass transition temperature and activation energy for thermal degradation among all the epoxy-silica nano/micro-composites. Indeed, an average activation energy value of 148.86 kJ/mol was recorded for the thermal degradation of unfilled epoxy resin. The maximum activation energy range was instead recorded for composites loaded with mesoporous microsilica. The EMC-5p50 sample showed the highest mean value of 217.6 kJ/mol. This remarkable enhancement was ascribed to the polymer invading the silica pores and forging formidable interfacial bonds.

show abstract

“…Therefore, the development of a storage material with low cost, good performance and high stability has become the focus of attention of many researchers. [1,2] In recent decades, the application of polymer materials, especially functionalized polyimide, in memory devices has aroused widespread concern due to its advantages of low cost, good scalability, simple structure, low power consumption and high-density three-dimensional (3D) arrays data storage, [3,4] etc. The charm of polyimides lies in its strong intramolecular and intermolecular interactions, which can make the molecular chain stack closely so as to improve its solvent resistance and thermal stability.…”

Section: Introductionmentioning

confidence: 99%

Tristable Memory Devices Based on Soluble Polyimides Containing Pendant Carbazole and Phenyl Groups

Chen

Zhu

et al. 2022

ChemistrySelect

View full text Add to dashboard Cite

As an important component of highly functional macromolecule semiconductor, two kinds of new diamine monomers, bis(5‐amino‐6‐methoxy‐[1,1’‐biphenyl]‐3‐yl) methanone (BAMBPM) and bis(5‐amino‐4’‐(9H‐carbazol‐9‐yl)‐6‐methoxy‐[1,1’‐biphenyl]‐3‐yl) methanone (BACzMBPM) were used as raw materials. Two kinds of soluble aromatic polyimides were prepared from BAMBPM and BACzMBPM by polycondensation with 2,2’,3,3’‐biphenyl tetracarboxylic dianhydride (BPDA) via a two‐step procedure. The obtained polyimides were sufficiently characterized, and showed superior organic solubility and excellent thermal stability, with a weight loss of 5 % weight loss above 300 °C. Memory devices with Al/polyimide/ITO structure were prepared by the traditional method of solution spin coating. Both devices show tristable characteristics, with high ON/OFF current ratios as high as 104 and long maintenance times of 104 seconds in the environmental atmosphere.

show abstract

The effects of long and bulky aromatic pendent groups with flexible linkages on the thermal, mechanical and electrical properties of the polyimides and their nanocomposites with functionalized silica

Abstract: Novel polyimides containing two long/bulky aromatic pendent chains and their nanocomposites with aromatic amine functionalized silica were prepared from a new diamine bis(4-aminophenyl)bis{3,4[(4-(8-quinolyloxymethyl carbonyl)phenoxy)]}methane.

Cited by 10 publications

References 64 publications

Simultaneously Improving the Optical, Dielectric, and Solubility Properties of Fluorene-Based Polyimide with Silyl Ether Side Groups

Simultaneously Improving the Optical, Dielectric, and Solubility Properties of Fluorene-Based Polyimide with Silyl Ether Side Groups

A Comprehensive Review on the Thermal Stability Assessment of Polymers and Composites for Aeronautics and Space Applications

Tristable Memory Devices Based on Soluble Polyimides Containing Pendant Carbazole and Phenyl Groups

Contact Info

Product

Resources

About