scholarly journals Influence of the Polyhedral Oligomeric Silsesquioxane n-Phenylaminopropyl - POSS in the Thermal Stability and the Glass Transition Temperature of Epoxy Resin

Polímeros ◽  
2013 ◽  
Vol 23 (3) ◽  
pp. 331-338 ◽  
Author(s):  
Vinicius PISTOR ◽  
Bluma G. SOARES ◽  
Raquel S. MAULER
2011 ◽  
Vol 2011 (HITEN) ◽  
pp. 000196-000200 ◽  
Author(s):  
Kenji Okamoto ◽  
Yuji Takematsu ◽  
Miyako Hitomi ◽  
Yoshinari Ikeda ◽  
Yoshikazu Takahashi

There is a demand to improve the thermal stability of epoxy molding resins used in the power module of SiC power chips operating at temperatures of 200°C or more. This paper describes a technique for increasing the thermal stability of the resin by decreasing molecular motion through the addition of nanofiller. The experimental results showed that the glass transition temperature (Tg) of the epoxy resin increased by approximately 30°C when the silica nanofiller was added. The epoxy resin added nanofiller was investigated in order to achieve the operation temperature 200°C of power module.


2022 ◽  
Author(s):  
Hong Chi ◽  
Guocheng Zhang ◽  
Ning Wang ◽  
Yaoguang Wang ◽  
Tianduo Li ◽  
...  

Glass transition temperature (Tg) is always deteriorated while improving the strength of epoxy resins which inherently suffered from brittleness. Herein, a novel linear polyhedral oligomeric silsesquioxane (POSS)-epoxy nano modifiers is...


Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 1058 ◽  
Author(s):  
Zhongxu Lan ◽  
Xueli Chen ◽  
Xiao Zhang ◽  
Chongyu Zhu ◽  
Yanlei Yu ◽  
...  

Optically transparent polyimides with excellent thermal stability and shape memory effect have potential applications in optoelectronic devices and aerospace industries. A series of optically transparent shape memory polyimide hybrid films are synthesized from 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) and 2,2′-bis-(trifluoromethyl)biphenyl-4,4′-diamine (TFMB) with various polyhedral oligomeric silsesquioxane (POSS) contents and then subjected to thermal imidization. The hybrid films show good optical transparency (>80% at 400 nm and >95% at 500 nm) with cutoff wavelengths ranging from 318 to 336 nm. Following the incorporation of the inorganic POSS structure, the hybrid films exhibit excellent thermal stability with glass transition temperature (Tg) ranging from 351 to 372 °C. The hybrid films possess the highest Tg compared with the previously-reported shape memory polymers. These findings show that POSS is successfully utilized to develop transparent polyimides with excellent thermal stability and shape memory effect.


Polymers ◽  
2019 ◽  
Vol 11 (10) ◽  
pp. 1548 ◽  
Author(s):  
Xingming Bian ◽  
Rui Tuo ◽  
Wei Yang ◽  
Yiran Zhang ◽  
Qing Xie ◽  
...  

Filled high thermal conductivity epoxy composite solves the problem of the low thermal conductivity of the epoxy resin itself, but the addition of the thermal conductive filler reduces the mechanical properties of the composite, which limits its application in the field of high voltage insulation. In this work, carboxyl-terminated butadiene nitrile liquid rubber (CTBN) was used to toughen the boron nitride-epoxy hybrid system, and the effects of different contents of CTBN on the mechanical properties, thermal conductivity, glass transition temperature, thermal stability, and dielectric properties of the composites were investigated. The results showed that when the content of CTBN was 5–15 wt.%, the CTBN formed a dispersed island structure in the epoxy resin matrix. The toughness of the composite increased by about 32%, the breakdown strength was improved, and the thermal conductivity was about 160% higher than that of pure epoxy resin. As the CTBN content increased, the glass transition temperature and thermal stability of the composite decreased and the dielectric constant and the dielectric loss increased. When the CTBN content is 10–15 wt.%, a toughened epoxy composite material with better comprehensive properties is obtained.


2021 ◽  
Vol 2 (2) ◽  
pp. 419-430
Author(s):  
Ankur Bajpai ◽  
James R. Davidson ◽  
Colin Robert

The tensile fracture mechanics and thermo-mechanical properties of mixtures composed of two kinds of epoxy resins of different chemical structures and functional groups were studied. The base resin was a bi-functional epoxy resin based on diglycidyl ether of bisphenol-A (DGEBA) and the other resins were (a) distilled triglycidylether of meta-amino phenol (b) 1, 6–naphthalene di epoxy and (c) fluorene di epoxy. This research shows that a small number of multifunctional epoxy systems, both di- and tri-functional, can significantly increase tensile strength (14%) over neat DGEBA while having no negative impact on other mechanical properties including glass transition temperature and elastic modulus. In fact, when compared to unmodified DGEBA, the tri-functional epoxy shows a slight increase (5%) in glass transition temperature at 10 wt.% concentration. The enhanced crosslinking of DGEBA (90 wt.%)/distilled triglycidylether of meta-amino phenol (10 wt.%) blends may be the possible reason for the improved glass transition. Finally, the influence of strain rate, temperature and moisture were investigated for both the neat DGEBA and the best performing modified system. The neat DGEBA was steadily outperformed by its modified counterpart in every condition.


Author(s):  
Takahisa Omata ◽  
Aman Sharma ◽  
Takuya Kinoshita ◽  
Issei Suzuki ◽  
Tomohiro Ishiyama ◽  
...  

In this study, the effect of GeO2 on the thermal stability and proton mobility (μH) of proton-conducting phosphate glasses was experimentally investigated using 22HO1/2−3NaO1/2−(12−x)LaO3/2−xGeO2−63PO5/2 glasses. Increasing glass transition temperature (Tg)...


2011 ◽  
Vol 71-78 ◽  
pp. 3591-3594 ◽  
Author(s):  
Xiao Lu Wang ◽  
Xiao Xiong Zha

Experimental results on tensile mechanics properties of GFRP bars at high temperatures are present in this paper. Thirty commercially produced GFRP tensile specimens of 8mm diameter were tested at high temperature ranging from 10°Cup to 500°C. Tensile test result indicates that, the ultimate tensile stress has significant reduction at two temperature zones, one is glass transition temperature of epoxy resin (80-120°C), with strength degradation 22%, the second is the soften temperature of glass fibers(about 400°C), the strength decrease drastically with almost linear rate and remained 33% residual strength at 500°C. The elastic modulus remained unchanged until glass transition temperature of epoxy resin, and the modulus declined linearly with the temperature elevating. Stress-strain relationships of GFRP bars exhibit liner performance even at high temperatures.


2014 ◽  
Vol 887-888 ◽  
pp. 97-100
Author(s):  
Xiao Lan Hu ◽  
Xi Lan ◽  
Teng Fei Lu ◽  
Hong Shan Yang ◽  
Ying Lai Yang

An acrylate resin copolymerized with epoxy and amino resin was prepared in this paper, and its polyhedral oligomeric silsesquioxane (POSS) modified nanocomposites were fabricated via physical blending. Results showed that glass transition temperature of the acrylate copolymer was about 7.9 oC via DSC. Dispersion of nanocomposites with aminopropyllsobutyl POSS is better than those with Octalsobutyl POSS. Moreover, glass transition temperatures of the nanocomposites with POSS are close to the acrylate copolymer matrix.


Sign in / Sign up

Export Citation Format

Share Document