scholarly journals Heteroaromatic Polyamides with Improved Thermal and Mechanical Properties

Polymers ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1793
Author(s):  
Miriam Trigo-López ◽  
Ana M. Sanjuán ◽  
Aranzazu Mendía ◽  
Asunción Muñoz ◽  
Félix C. García ◽  
...  

We prepared high-performance aromatic copolyamides, containing bithiazole and thiazolo-thiazole groups in their main chain, from aromatic diamines and isophthaloyl chloride, to further improve the prominent thermal behavior and exceptional mechanical properties of commercial aramid fibers. The introduction of these groups leads to aramids with improved strength and moduli compared to commercial meta-oriented aromatic polyamides, together with an increase of their thermal performance. Moreover, their solubility, water uptake, and optical properties were evaluated in this work.

RSC Advances ◽  
2014 ◽  
Vol 4 (107) ◽  
pp. 62550-62556 ◽  
Author(s):  
Kan Zhang ◽  
Jia Liu ◽  
Hatsuo Ishida

A novel approach has been developed to prepare thermosetting polyimides by incorporating benzoxazine structure as a repeating unit in the main chain. This method allows the crosslinked polyimide with excellent thermal and mechanical properties.


2012 ◽  
Vol 549 ◽  
pp. 45-49
Author(s):  
Wei Hu ◽  
Guang Xian Zhang ◽  
Feng Xiu Zhang ◽  
Hui Zheng ◽  
Ming Lu

Aromatic polyamides are high performance materials, having outstanding thermal and mechanical properties. Poly(2,5-Diamino-terephthalic acid) (PATA) was designed as a novel aromatic polyamide with high strength and modulus. In this paper, 2,5-Diamino-terephthalic acid (DATA), as a monomer of PATA, was synthesized from 2,5-Dimetyl-1,4-phenyldiamine (DPA). First step was the amidation of DPA by reacting with acetic anhydride to protect amido group. Then N-(4–Acetylamino-2,5-dimethyl–phenyl)-acetamide (AMPA) was oxidized by potassium permanganate. Finally, AMPA was hydrolyzed by sodium hydroxide and the monomer DATA was precipitated by hydrochloric acid around PH 5. DATA and all the intermediate products were characterized and confirmed by 1HNMR and FT-IR spectra. They were all in great agreement with the proposed structure. The overall yield of DATA was about 40.0%.


2021 ◽  
Vol 12 (16) ◽  
pp. 2379-2388
Author(s):  
Jules Stouten ◽  
Aleksandra A. Wróblewska ◽  
Glenn Grit ◽  
Jurrie Noordijk ◽  
Bert Gebben ◽  
...  

A new biobased alternative for terephthalic acid (TPA) in (semi-)aromatic polyamides is proposed, namely 4-carboxybenzene propionic acid (4CBPA).


RSC Advances ◽  
2016 ◽  
Vol 6 (90) ◽  
pp. 87013-87020 ◽  
Author(s):  
Kaiju Luo ◽  
Yan Wang ◽  
Junrong Yu ◽  
Jing Zhu ◽  
Zuming Hu

Aromatic furanic polyamides with relatively high molecular weight were synthesized, and good thermal stability and mechanical properties were demonstrated.


Author(s):  
Arun Gowda ◽  
Annita Zhong ◽  
Sandeep Tonapi ◽  
Kaustubh Nagarkar ◽  
K. Srihari

Thermal Interface Materials (TIMs) play a key role in the thermal management of microelectronics by providing a path of low thermal impedance between the heat generating devices and the heat dissipating components (heat spreader/sink). In addition, TIMs need to reliably maintain this low thermal resistance path throughout the operating life of the device. Currently, several different TIM material solutions are employed to dissipate heat away from semiconductor devices. Thermal greases, adhesives, gels, pads, and phase change materials are among these material solutions. Each material system has its own advantages and associated application space. While thermal greases offer excellent thermal performance, their uncured state makes them susceptible to pump-out and other degradation mechanisms. On the other hand, adhesives offer structural support but offer a higher heat resistance path. Gels are designed to provide a level of cross-linking to allow the thermal performance of greases and prevent premature degradation. However, the degree of crosslinking can have a significant effect of the behavior of gels. In this research, TIMs with varying cross-linking densities are studied and their thermal and mechanical properties reported. The base resin systems and fillers were maintained constant, while slight compositional alternations were made to induce different degrees of cross-linking.


2016 ◽  
Vol 721 ◽  
pp. 23-27 ◽  
Author(s):  
Ilya Kobykhno ◽  
Oleg Tolochko ◽  
Ekaterina Vasilyeva ◽  
Andrei Didenko ◽  
Danila Kuznetcov ◽  
...  

The paper experimentally studies the effect of meta and para- substitution of the amino groups in the diamine used in the synthesis of multiblock copolymers. The way for synthesis of new multiblock copolymers with the possibility of replacing the diamine in the polymer structure was shown. Thermal and mechanical properties of synthesized copolymers had been characterized by means of differential scanning calorimetry, thermogravimetric analysis, dynamic mechanical thermal analysis and by nanoindentation and tensile test.


RSC Advances ◽  
2015 ◽  
Vol 5 (72) ◽  
pp. 58821-58831 ◽  
Author(s):  
Yiqun Wang ◽  
Kaichang Kou ◽  
Guanglei Wu ◽  
Ailing Feng ◽  
Longhai Zhuo

A high-performance polymer composite was fabricated using Bz-allyl/BMI/BADCy resin, in which the BMI/BADCy resin was modified with Bz-allyl to improve its dielectric, thermal and mechanical properties and the cross-linking degree after curing.


2011 ◽  
Vol 45 (24) ◽  
pp. 2587-2592 ◽  
Author(s):  
Jian Yang ◽  
Jiachun Zhong ◽  
Rui Zhao ◽  
Xiaobo Liu

The continuous glass fiber-reinforced polyarylene ether nitriles (PEN) composites were successfully fabricated from PEN pre-impregnated glass fabric mates and PEN films using a film-stacking method. The work involved heat treatment for crosslinking reaction of PEN, and so it provided an interesting comparison of how heat treatment can influence the properties of composites. Detailed study on heat treatments for crosslinking reaction of PEN in the catalysis of the ZnCl2 at high temperature promoting the thermal and mechanical properties of composites were also investigated. The results showed that the thermal and mechanical properties of composites were enhanced by heat treatment, which is due to the fact that PEN resins could be crosslinked by the catalytic action of ZnCl2 at high temperature and formed triazine rings with a more thermally stable structure.


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