scholarly journals Preparation and Properties of Poly(imide-siloxane) Copolymer Composite Films with Micro-Al2O3 Particles

2019 ◽  
Vol 9 (3) ◽  
pp. 548 ◽  
Author(s):  
Ju-Young Choi ◽  
Kyeong-Nam Nam ◽  
Seung-Won Jin ◽  
Dong-Min Kim ◽  
In-Ho Song ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Mechanical Property ◽  
Thermal Stability ◽  
Molecular Weight ◽  
Matrix Material ◽  
Composite Films ◽  
Free Standing ◽  
Al2o3 Composite ◽  
Al2o3 Particles ◽  
Poly Imide

In the current study, poly(imide-siloxane) copolymers (PIs) with different siloxane contents were synthesized and used as a matrix material for PI/Al2O3 composites. The PIs were characterized via their molecular weight, film quality, and thermal stability. Among the PI films, free-standing and flexible PI films were selected and used to prepare PI/Al2O3 composite films, with different Al2O3 loadings. The thermal conductivity, thermal stability, mechanical property, film flexibility, and morphology of the PI/Al2O3 composite films were investigated for their application as heat-dissipating material.

scholarly journals In situ synthesis of MWCNT-graft-polyimides: thermal stability, mechanical property and thermal conductivity

RSC Advances ◽  
2020 ◽  
Vol 10 (23) ◽  
pp. 13517-13524
Author(s):  
Chunbo Wang ◽  
Bing Cong ◽  
Junyu Zhao ◽  
Xiaogang Zhao ◽  
Daming Wang ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Mechanical Property ◽  
Thermal Stability ◽  
In Situ Synthesis ◽  
Enhanced Thermal Conductivity

In situ synthesis of MWCNT-graft-polyimides enhanced thermal conductivity at a relatively low loading.

scholarly journals Effect of Regenerated Cellulose Fibers Derived from Black Oat on Functional Properties of PVA-Based Biocomposite Film

Processes ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1149
Author(s):  
Naresh Shahi ◽  
Gautam Joshi ◽  
Byungjin Min
Keyword(s):  
Mechanical Property ◽  
Thermal Stability ◽  
Functional Properties ◽  
Crop Production ◽  
Transmission Rate ◽  
Composite Films ◽  
Cellulose Fibers ◽  
Poly Vinyl Alcohol ◽  
Regenerated Cellulose ◽  
Control Film

In this study, agricultural residue from black oat, a cover crop usually grown to improve soil nutrients between the periods of regular crop production, was used as a source of cellulose fibers. Concentrations of 1, 3, and 5 wt. % of regenerated cellulose (RC) fibers blended in poly(vinyl alcohol) (PVA) solution were used to prepare the reinforced composite films (CFs) by the solvent cast method. Compared to neat PVA film (control), the effects of RC addition on functional properties of CFs, such as water absorption, transparency, thermal stability, and mechanical property were investigated. All CFs with different RC concentrations exhibited improved mechanical property and thermal stability while the swelling property was decreased, and no significant changes were observed in the film transparency as compared with the control film. Among the CFs, films with 3% RC significantly decreased water vapor transmission rate, swelling, and soluble fraction (p < 0.05). In addition, Young’s modulus and tensile strength were increased by 40 MPa and 3 MPa, respectively, while elongation at break was decreased by 4%, compared to the control film. The results indicate that RC from black oat might be feasible as potential bio fillers to improve film properties in a bio-based composite matrix.

scholarly journals Largely enhanced thermal conductivity and thermal stability of ultra high molecular weight polyethylene composites via BN/CNT synergy

RSC Advances ◽  
2019 ◽  
Vol 9 (70) ◽  
pp. 40800-40809
Author(s):  
Yiyou Guo ◽  
Changlin Cao ◽  
Fubin Luo ◽  
Baoquan Huang ◽  
Liren Xiao ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Carbon Nanotubes ◽  
Thermal Stability ◽  
Molecular Weight ◽  
Boron Nitride ◽  
Thermal Conduction ◽  
Conduction Path ◽  
Ultra High Molecular Weight ◽  
Thermal Stability Of ◽  
Enhanced Thermal Conductivity

The carbon nanotubes (CNTs) synergistically assist boron nitride microsheets (BNs) to form a more continuous and effective thermal conduction path.

scholarly journals Investigation on the Properties of PMMA/Reactive Halloysite Nanocomposites Based on Halloysite with Double Bonds

Polymers ◽  
2018 ◽  
Vol 10 (8) ◽  
pp. 919 ◽  
Author(s):  
Shiwei Chen ◽  
Zhizhou Yang ◽  
Fuzhong Wang
Keyword(s):  
Mechanical Property ◽  
Thermal Stability ◽  
Molecular Weight ◽  
Polymer Nanocomposites ◽  
Moisture Absorption ◽  
Young Modulus ◽  
Double Bonds ◽  
Scanning Calorimetry ◽  
General Applicability ◽  
Thermal Stability Of

PMMA/reactive halloysite nanocomposites were firstly prepared using reactive halloysite with double bonds. The halloysite was functionalized to improve its dispersion in the polymer matrix. The reactive halloysite could increase the molecular weight of PMMA. The molecular distribution of PMMA/reactive halloysite nanocomposite was more uniform than that of PMMA. The moisture absorption of PMMA/reactive halloysite nanocomposite increased with the addition of the reactive halloysite. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) confirmed that the thermal stability of PMMA/reactive halloysite nanocomposites was greatly enhanced. Significant improvement in the mechanical property of PMMA nanocomposites was achieved by the addition of 3 wt % reactive halloysite. A 31.1% increase in tensile strength and a 64.2% increase in Young’ modulus of the nanocomposites with 3 wt % of the reactive halloysite were achieved. Finally, the formation mechanism of PMMA/reactive halloysites nanocomposites was proposed. This approach demonstrated the potential for general applicability to other polymer nanocomposites.

scholarly journals Bioinspired Dielectric Film with Superior Mechanical Properties and Ultrahigh Electric Breakdown Strength Made from Aramid Nanofibers and Alumina Nanoplates

Polymers ◽  
2021 ◽  
Vol 13 (18) ◽  
pp. 3093
Author(s):  
Qiu-Wanyu Qing ◽  
Cheng-Mei Wei ◽  
Qi-Han Li ◽  
Rui Liu ◽  
Zong-Xi Zhang ◽  
...  
Keyword(s):  
Thermal Stability ◽  
Hydrogen Bonding ◽  
Composite Film ◽  
Breakdown Strength ◽  
Composite Films ◽  
Electrical Equipment ◽  
Electric Breakdown ◽  
Excellent Thermal Stability ◽  
Practical Applications ◽  
Al2o3 Composite

Materials with excellent thermal stability, mechanical, and insulating properties are highly desirable for electrical equipment with high voltage and high power. However, simultaneously integrating these performance portfolios into a single material remains a great challenge. Here, we describe a new strategy to prepare composite film by combining one-dimensional (1D) rigid aramid nanofiber (ANF) with 2D alumina (Al2O3) nanoplates using the carboxylated chitosan acting as hydrogen bonding donors as well as soft interlocking agent. A biomimetic nacreous ‘brick-and-mortar’ structure with a 3D hydrogen bonding network is constructed in the obtained ANF/chitosan/Al2O3 composite films, which provides the composite films with exceptional mechanical and dielectric properties. The ANF/chitosan/Al2O3 composite film exhibits an ultrahigh electric breakdown strength of 320.1 kV/mm at 15 wt % Al2O3 loading, which is 50.6% higher than that of the neat ANF film. Meanwhile, a large elongation at break of 17.22% is achieved for the composite film, integrated with high tensile strength (~233 MPa), low dielectric loss (<0.02), and remarkable thermal stability. These findings shed new light on the fabrication of multifunctional insulating materials and broaden their practical applications in the field of advanced electrics and electrical devices.

Highly anisotropic thermal conductivity and electrical insulation of nanofibrillated cellulose/Al2O3@rGO composite films: effect of the particle size

2021 ◽  
Author(s):  
Meng Ma ◽  
Qindan Chu ◽  
Hao Lin ◽  
Lin Xu ◽  
Huiwen He ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Particle Size ◽  
Heat Dissipation ◽  
Composite Films ◽  
Nanofibrillated Cellulose ◽  
Al2o3 Particle ◽  
Electrical Insulation ◽  
Drying Methods ◽  
Anisotropic Thermal Conductivity ◽  
Al2o3 Particles

Abstract Abstract: Nanofibrillated cellulose (NFC) film has received tremendous attention due to its excellent electrical insulation, which shows great application prospects in the field of electronic devices. However, the low efficient heat dissipation of NFC film largely limits its use in advanced applications. In this work, the rGO hybrid fillers loaded alumina (Al2O3) particles with different sizes were synthesized by different drying methods and then they were mixed with NFC to prepare a series of NFC-based composite films. The effect of Al2O3 particle sizes on the thermal conductivity of NFC-based composite films was studied. The results showed that the surface areas of l-Al2O3 particles were smaller than that of s-Al2O3 particles, resulting in the smaller interface thermal resistance and superior thermal conductivity of the film containing l-Al2O3 particles. The NFC-based composite films showed great potential for the applications in thermal management by adjusting the particle size of fillers.

Upconversion nanoparticle–Ag@C@Ag composite films for rapid temperature sensing

CrystEngComm ◽  
2021 ◽  
Author(s):  
Hu Huang ◽  
Lingqiong Wu ◽  
Shengbin Cheng ◽  
Xiaofeng Wu ◽  
Shiping Zhan ◽  
...  
Keyword(s):  
Thermal Conductivity ◽  
Ag Nanoparticles ◽  
Response Rate ◽  
Composite Films ◽  
Temperature Sensing ◽  
Upconversion Nanoparticles ◽  
Rapid Temperature

The response rate of optical temperature sensing of upconversion nanoparticles is significantly improved by coupling with Ag@C@Ag nanoparticles which have excellent thermal conductivity.

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