聚乙烯/扩展石墨复合材料的热绝缘泡,可减少辐射和导电
Pengjian Gong1,2, Minh-Phuong Tran1, Piyapong Buahom1
1Microcellular Plastics Manufacturing Laboratory (MPML), Department of Mechanical and Industrial Engineering, University of Toronto, 5 King's College Road, Toronto, ON M5S 3G8, Canada.
Polymers
|April 26, 2025
概括
将膨胀石墨 (EG) 添加到聚钢 (PS) 泡中,可显著改善热绝缘. 这种新的材料设计和泡过程实现了超热绝缘特性,有效地减少了传热.
科学领域:
- 材料科学 材料科学 材料科学
- 热力工程是热力工程中的一个.
- 纳米技术纳米技术
背景情况:
- 辐射和固体导热性显著促进了聚合物泡中的热传递.
- 现有的隔热材料在减少这些特定的传热元件方面经常面临局限性.
研究的目的:
- 为了研究聚钢 (PS) 泡的隔热行为,包括扩展石墨 (EG).
- 通过优化材料组成和发泡过程,开发一种超热绝缘复合泡.
主要方法:
- 将低度 (≤2重量%) 的膨胀石墨 (EG) 纳入聚烯 (PS) 泡中.
- 对隔热性能进行系统和定量调查.
- 使用共吹剂优化超临界二氧化碳发泡过程.
主要成果:
- 对PS泡块添加1重%的EG抑制了90%以上的辐射导热率.
- 总导热率从36.5降至30.2mW·m−1·K−1以1 wt%的EG.降低至30.2 mW·m−1·K−1.
- 实现了超热绝缘PS/EG泡的创纪录的低导热率19.6mW·m−1·K−1.
结论:
- 复合材料和泡工艺设计对于实现超热绝缘至关重要.
- 高红外吸收添加剂,大膨胀比泡和低气体导电性共吹剂是关键策略.
- 这种方法可以为各种应用开发先进的绝缘材料.
相关概念视频
Thermal Insulation in Masonry Walls
93
In hot, dry climates, the thermal mass of masonry walls can be beneficial, absorbing heat during the day and releasing it at night, thereby stabilizing indoor temperatures. However, in most other climates, additional insulation is necessary to enhance thermal resistance.
External insulation can be applied using an Exterior Insulation and Finish System (EIFS), which involves affixing panels of plastic foam to the wall and covering them with a polymeric stucco reinforced with glass fiber mesh....
External insulation can be applied using an Exterior Insulation and Finish System (EIFS), which involves affixing panels of plastic foam to the wall and covering them with a polymeric stucco reinforced with glass fiber mesh....
93
Conduction, Convection and Radiation: Problem Solving
1.1K
There are three methods by which heat transfer can take place: conduction, convection, and radiation. Each method has unique and interesting characteristics, but all three have two things in common: they transfer heat solely because of a temperature difference; and the greater the temperature difference, the faster the heat transfer.
In order to solve a problem related to heat transfer, first of all, the situation needs to be examined to determine the type of heat transfer involved. This could...
In order to solve a problem related to heat transfer, first of all, the situation needs to be examined to determine the type of heat transfer involved. This could...
1.1K
Radiation: Applications
1.1K
The average temperature of Earth is the subject of much current discussion. Earth is in radiative contact with both the Sun and dark space; it receives almost all its energy from the radiation of the Sun and reflects some of it into outer space. Dark space is very cold, about 3 K, so Earth radiates energy into it. For instance, heat transfer occurs from soil and grasses, the rate of which can be so rapid that frost can occur on clear summer evenings, even in warm latitudes.
The average...
The average...
1.1K
Mass Concreting
44
Mass concreting refers to the process of placing large volumes of concrete, such as in gravity dams. The heat generated during the cement hydration process and differential cooling rates within the concrete mass can lead to a temperature gradient, which can result in thermal cracks in the concrete mass.
To reduce the risk of such cracking, the concrete mix may incorporate low-heat cement and pozzolans to reduce the temperature rise. Pre-cooled angular aggregates and water-reducing admixtures...
To reduce the risk of such cracking, the concrete mix may incorporate low-heat cement and pozzolans to reduce the temperature rise. Pre-cooled angular aggregates and water-reducing admixtures...
44
Absorption of Radiation
680
The rate of heat transfer by emitted radiation is described by the Stefan-Boltzmann law of radiation:
680
Molecular Weight of Step-Growth Polymers
2.1K
Step growth polymerization involves bi or multifunctional monomers. Bifunctional monomers react to form linear step growth polymers, whereas multifunctional monomers react to form non-linear or branched polymers.
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
As the step-growth polymerization involves step-wise condensation of monomers, the molecular weight also builds up eventually. Consequently, high molecular weight polymers are obtained at the late stages of the polymerization, where 99% of monomers have been consumed.
The extent of the...
2.1K


