Towards solution-processable, thermally robust, transparent polyimide-chain-end tethered organosilicate nanohybrids

Nam, Ki Ho; Jin, Jeong; Lee, Dong‐Hoon; Han, Haksoo; Goh, Munju; Yu, Jaesang; Ku, Bon‐Cheol; You, Nam Ho

doi:10.1016/j.compositesb.2018.11.029

Cited by 47 publications

(24 citation statements)

References 61 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“… 13 − 15 For instance, the PI–organosilicate hybrid is a competitive modifier to simultaneously improve the dielectric and optical properties. 16 − 21 However, PI–organosilicate hybrids still have some disadvantages, such as the complex preparation process, the low miscibility between the PI and silicate components, and the poor solubility in organic solvents. In addition, the preparation of PI backbone containing siloxane moieties is another way to obtain the transparent or low-dielectric-constant PIs.…”

Section: Introductionmentioning

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: Introductionmentioning

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

“…Comparing the PI 1-6 series from the aspect of the monomer structure, the linkage structure between the phenyls of the diamine was an important factor the chain mobility [11]. PIs with ODA had a lower Tg owing to the flexible ether linkage of ODA, because the polymer chain moved more easily.…”

Section: Thermal Propertiesmentioning

confidence: 99%

“…Regardless of those attractive properties of PIs, environmental restrictions and their poor processability hinders their further usage in various industries. The need for high-temperature processes and great amount of hazardous organic solvents usage such as N-methyl-2-pyrrolidone Polymers 2021, 13, 3824 2 of 13 (NMP) and dimethylacetamide (DMAc) in the PIs synthesis process still requires further research to develop more sustainable synthetic routes [11,12].…”

Section: Introductionmentioning

confidence: 99%

Highly Soluble Fluorinated Polyimides Synthesized with Hydrothermal Process towards Sustainable Green Technology

et al. 2021

Self Cite

View full text Add to dashboard Cite

Polyimides, a widely used engineering plastic, require use of large amounts of toxic and hazardous organic solvents which threaten our daily lives, calling for new and easy synthetic methods for sustainable environmentally friendly development. In this paper, highly soluble fluorinated polyimides based on 4,4′-(hexafluoroisopropylidene) diphthalic anhydride were synthesized via hydrothermal process without using any toxic organic solvents and the advantages of the newly demonstrated synthetic methods are shown by comparative analysis performed with the two conventional synthetic methods using organic solvent: thermal and chemical imidization. Lower temperature is required (~200 °C) compared to thermal imidization and functional groups for high fusibility formed more easily compared to chemical imidization. According to the comparative analysis, hydrothermally synthesized PIs showed excellent solubility and maintained high thermal stability (>500 °C) and glass transition temperature (>300 °C) compared to conventional PI. The hydrothermally synthesized polyimide is much more convenient to store and manage than other form of polyimide which is much more stable when it is exposed to humidity as it is a powder form. The hydrothermal synthetic method is verified to be a “Green” and facile method for sustainable PI synthesis.

show abstract

“…Researchers have proved that the transparency of the PI membrane can be improved by introducing strong electronegative groups, 33 alicyclic structures, 34 substituent groups, 35 and polymerizable inorganic nanoparticles. 36 These methods to improve the transmittance are also applicable to the design of transparent PI aerogels.…”

Section: ■ Introductionmentioning

confidence: 99%

Polyimide Aerogel Membranes with Adjustable Transparency and High Flexibility for Highly Efficient Solar Thermal Collection

Hou

Zhang

Fang

2021

ACS Sustainable Chem. Eng.

View full text Add to dashboard Cite

Aerogel-based solar collectors inherently possess superinsulated performance, which can achieve green and sustainable thermal collection under atmospheric pressure without the need of a vacuum gap. However, the inherent brittleness, low transparency, and weak mechanical properties of aerogels limit the practical application as solar collectors. Herein, polyimide aerogel membranes (PIAMs) with integrated properties of robust flexibility, high transparency, and low thermal conductivity have been prepared. The prepared PIAMs achieve the adjustable transparency and significant transformation from fragility to high flexibility by introducing the asymmetric molecular structure. In particular, the prepared PIAMs realize an average optical transmittance of ∼90% over the long wavelength range of 500–2650 nm and exhibit high flexibility, a low density of 0.161 g/cm3, a low thermal conductivity of 0.045 W/mK, and a robust tensile strength of 6.02 MPa. Moreover, a simple and low-cost parabolic trough solar collecting device is assembled using PIAMs as an exterior structure, which could operate at atmospheric conditions and achieve highly efficient thermal collection. The results demonstrate that the effective thermal collecting temperature of solar collector was up to 231.5 °C. The as-prepared PIAMs with robust flexibility and high optical transparency can be used as the candidate for the application of solar collectors and advanced optical elements.

show abstract

Towards solution-processable, thermally robust, transparent polyimide-chain-end tethered organosilicate nanohybrids

Cited by 47 publications

References 61 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

Highly Soluble Fluorinated Polyimides Synthesized with Hydrothermal Process towards Sustainable Green Technology

Polyimide Aerogel Membranes with Adjustable Transparency and High Flexibility for Highly Efficient Solar Thermal Collection

Contact Info

Product

Resources

About