scholarly journals Phase Change Energy Storage Elastic Fiber: A Simple Route to Personal Thermal Management

Polymers ◽  
2021 ◽  
Vol 14 (1) ◽  
pp. 53
Author(s):  
Weipei Li ◽  
Liqing Xu ◽  
Xiangqin Wang ◽  
Ruitian Zhu ◽  
Yurong Yan
Keyword(s):  
Phase Change ◽  
Recovery Rate ◽  
Elastic Recovery ◽  
Thermoplastic Polyurethane ◽  
Elastic Fiber ◽  
Waterborne Polyurethane ◽  
High Elasticity ◽  
Application Potential ◽  
Hierarchical Pore ◽  
Recovery Cycles

A novel thermoplastic polyurethane (TPU) PCFs possessing a high loaded ratio and high elasticity was simply prepared by vacuum absorption following wet spinning, then coated by waterborne polyurethane (WPU). Octadecane (OCC), hexadecanol (HEO), and stearic acid (SA), which have different tendencies to form hydrogen bonds with TPU, were selected as PCMs, and their thermal behavior, thermal storge properties, and elasticity were systematically studied, respectively. The hierarchical pore structure though from the sheath to the core part of TPU filaments weakened the influence of the nonfreezing layer and hydrogen bond on the crystallization behavior of PCMs. The resulting HEO/TPU fiber has the highest enthalpy of 208.1 J/g compared with OCC and SA. Moreover, the HEO/TPU fiber has an elongation at break of 354.8% when the phase change enthalpy is as high as 177.8 J/g and the phase change enthalpy is still 174.5 J/g after fifty cycles. After ten tensile recovery cycles, the elastic recovery rate of HEO/TPU fiber was only 71.3%. When the HEO in the fiber was liquid state, the elastic recovery rate of HEO/TPU fiber promoted to 91.6%. This elastic PCFs have excellent thermal cycle stability, elastic recovery, and temperature sensitivity. It has great application potential in the fields of flexible wearable devices, intelligent fabrics, and temperature sensors.

scholarly journals Using the Rheological Index to Quantitatively Evaluate the Mechanical Performance of High-Elasticity Modified Asphalt

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Jiani Wang ◽  
Zhongjun Xue ◽  
Meng Guo ◽  
Shuaixiang Zhang
Keyword(s):  
Modulus Of Elasticity ◽  
Recovery Rate ◽  
Bridge Deck ◽  
Mechanical Performance ◽  
Elastic Recovery ◽  
High Temperature Deformation ◽  
Temperature Deformation ◽  
Modified Asphalt ◽  
Recovery Capacity ◽  
High Elasticity

High-elasticity modified asphalt is widely used in OGFC and bridge deck paving due to its high viscosity and strong displacement recovery capacity. It can improve the high-temperature deformation resistance and elastic recovery ability of the pavement. Especially in bridge deck pavement, high-elastic modified asphalt can inhibit the formation of reflective cracks and extend the service life. In order to quantitatively evaluate properties of the high-elasticity modified asphalt, rheological properties are studied by using a dynamic shear rheometer (DSR) test. The parameters were fitted with the Burgers model, and the constitutive equation was established. The 3 s elastic recovery rate E r was proposed to quantitatively evaluate the elastic recovery of high-elasticity modified asphalt. The experimental results show that the instantaneous modulus of elasticity G 0 and the delayed modulus of elasticity G 1 can be used to evaluate the elastic capacity. E r can quantitatively evaluate the elastic resilience of high-elasticity modified asphalt. The correlation coefficient between the test results of high-elasticity modified asphalt and those of impact toughness evaluation reached 0.9966, and the 3 s elastic recovery rate E r could be used to evaluate the elastic recovery ability of high-elasticity modified asphalt.

Synthesis and Properties of a Novel Environmentally Friendly Phase Change Energy Storage Coating Additive

2013 ◽  
Vol 805-806 ◽  
pp. 1538-1541
Author(s):  
Peng Fu ◽  
Peng Xi ◽  
Fu Lai Zhao ◽  
Bo Wen Cheng
Keyword(s):  
Energy Storage ◽  
Phase Change ◽  
Synthesis Method ◽  
Waterborne Polyurethane ◽  
Water Soluble ◽  
Water As Solvent ◽  
Soft Segments ◽  
New Type ◽  
Energy Storage Material ◽  
Very High

Waterborne polyurethane (PU) coatings are diluted with water as the medium, without volatile organic solvents and harmful to human body and environment. Adding insulation materials in building individually is a waste of resource. We found a kind of waterborne PU phase change energy storage material easily dissolved and formed film after solvent evaporating having the potential of coating. In this article, we synthesized a new kind of waterborne PU phase change energy storage coating additive via two-step synthesis method, of which a new type of aromatic tetrahydroxycompound (ATTC) is used as branch unit, 4, 4'-diphenylmethanediisocyanate (MDI) and polyethylene glycol (PEG) respectively as hard and soft segments. POM photographs show that the sphaerocrystals of this new coating additive can reach 200-500μm. The crystal structure is characterized by XRD, and the phase change unit is PEG. DSC tests show that the phase change enthalpy value of this coating additive is very high reached more than 90 J/g. The preservation of this water-soluble PU coating is relatively simple, using water as solvent, which can be easy to dissolve in water and form film after water evaporated.

Adhesion of Crystalline GeSbTe/TiN Interface Characterized by Four Point Bend, Nanoindentation, and Nanoscratch

2007 ◽  
Vol 997 ◽  
Author(s):  
guohua Wei ◽  
Jun Liu ◽  
David Fillmore ◽  
Mike Violette ◽  
Shifeng Lu
Keyword(s):  
Phase Change ◽  
Process Development ◽  
Structural Phase ◽  
The Past ◽  
Two Samples ◽  
Application Potential ◽  
Point Bend ◽  
Chalcogenide Materials ◽  
Poor Adhesion ◽  
Structural Phase Change

AbstractReversible structural phase change phenomenon of certain chalcogenide materials has been investigated extensively in the past decades. Among various phase change chalcogenide materials, Ge2Sb2Te5 (GST) is the most studied material due to its superior optical, electrical and mechanical properties. One of the challenges in using GST is the poor adhesion between crystalline GeSbTe (c-GST) and the substrate, such as TiN. In this work, the adhesion of the c-GST/TiN interface of two samples deposited by different techniques was characterized using four-point bend, nanoindentation and nanoscratch techniques. The nanoindentation and nanoscratch data agree well with the four point bend data. The paper also discusses the application potential of nanoindentation and nanoscratch techniques as qualitative methods for adhesion evaluation in semiconductor process development.

Optimum Efficiencies and Phase Change Temperatures in Latent Heat Storage Systems

1994 ◽  
Vol 116 (1) ◽  
pp. 79-86 ◽  
Author(s):  
S. Aceves-Saborio ◽  
H. Nakamura ◽  
G. M. Reistad
Keyword(s):  
Phase Change ◽  
Latent Heat ◽  
Heat Storage ◽  
Storage Systems ◽  
Broad Class ◽  
Operating Conditions ◽  
Latent Heat Storage ◽  
Efficient Operation ◽  
Basic Model ◽  
Application Potential

This paper presents an analysis of a class of latent heat storage systems (LHSS). The analysis is based on a lumped model (the basic model) that allows a broad class of LHSSs to be completely specified, with only two parameters and a set of operating temperatures, while still retaining the main thermodynamic aspects associated with its operation. Characterization of the performance in this manner permits the broad base application potential of such systems to be viewed. This modeling is in contrast to most studies to date, which employ many parameters to include details of specific systems, and therefore obscure, to a great extent, this broad-based application potential. The basic model is later modified in three ways to analyze operating conditions that either occur in practical units or are desirable for an improved operation of the units. The modifications include, first, the consideration of the LHSS as being formed by many independent phase-change material (PCM) capsules. Second, the possibility of having PCMs with different phase change temperatures filling the capsules. Third, the case when the PCM melts over a temperature range. The results indicate that the efficiency of the basic model represents a higher bound for the efficient operation of LHSSs with negligible sensible storage capacity, and a single PCM. Using multiple PCMs within a LHSS results in higher efficiencies. These efficiencies set higher bounds for efficiency of any sensible or latent heat storage system, and also represent the only possibility for reversible operation of LHSS.

Effect of Antioxidant on Properties of Thermoplastic Natural Rubber Based on ENR/TPU Blends

2012 ◽  
Vol 626 ◽  
pp. 229-232 ◽  
Author(s):  
Ekwipoo Kalkornsurapranee ◽  
Charoen Nakason ◽  
Claudia Kummerlöwe ◽  
Norbert Vennemann
Keyword(s):  
Thermal Properties ◽  
Natural Rubber ◽  
High Performance ◽  
Thermoplastic Polyurethane ◽  
Oxidative Degradation ◽  
The Novel ◽  
Dynamic Vulcanization ◽  
High Elasticity ◽  
Thermoplastic Natural Rubber ◽  
Temperature Scanning

Thermoplastic natural rubber based on epoxidized natural rubber (ENR) and thermoplastic polyurethane (TPU) blend was prepared via dynamic vulcanization process. The main objective is to improve thermal properties of the blends. Two types of antioxidant: phenolic antioxidant (Wingstay®L) and N-(1,3-dimethzlbutyl)-N-Phenyl-p-phenylenediamine (6PPD) were used to improve oxidative degradation of the blends. It was found that thermal properties in term of thermal elastic properties and thermal stability can be improved by adding the antioxidants and 6PPD gave the blend with the highest thermal properties. These were measured based on temperature scanning stress relaxation (TSSR) technique. Incorporation of ENR into the TPU caused reduction of the hardness, improved thermal properties, elasticity and oil resistance compared to the neat TPU. These results indicated that the novel high performance TPNRs with high elasticity can be prepared.

Parametric Study on Wall Springback in Tailor Welded Long Channels

2016 ◽  
Author(s):  
Chetan P. Nikhare
Keyword(s):  
Parametric Study ◽  
Elastic Recovery ◽  
Influencing Factor ◽  
Weld Line ◽  
High Strength ◽  
Back Edge ◽  
High Elasticity ◽  
Large Length ◽  
Tailor Welded Blank ◽  
The Common

The common challenge found in cases of high elasticity or high strength or both property materials after forming is springback. The part unloaded after forming tends to recover elastically and the displacement due to elastic recovery is called springback. In this paper, the 3D channels with large length were deformed numerically and parametric study on the wall springback at different section was predicted. For this purpose tailor welded blank was considered. The geometric change along the long axis was also discussed. In addition the effect of parameters on wall springback was also analyzed. The new division factor was included to normalize the springback based on thickness and strength. It was found that the strength ratio and die and punch radius were the top influencing factor for front edge and weld line springback while thickness ratio was the most affecting parameter for the back edge springback.

Preparation and research of waterborne polyurethane phase change material

2018 ◽  
Vol 189 (1) ◽  
pp. 175-188
Author(s):  
Wei Hong ◽  
Chuntian Zhang ◽  
Jing Sun ◽  
Shu Wu ◽  
Kaijun Zhang ◽  
...  
Keyword(s):  
Phase Change ◽  
Phase Change Material ◽  
Waterborne Polyurethane ◽  
Change Material

scholarly journals Process Property Studies of Melt Blown Thermoplastic Polyurethane Polymers for Protective Apparel

2005 ◽  
Vol os-14 (4) ◽  
pp. 1558925005os-14
Author(s):  
Youn Eung Lee ◽  
Larry C. Wadsworth
Keyword(s):  
Thermoplastic Polyurethane ◽  
Elastic Fiber ◽  
Chemical Warfare Agents ◽  
Woven Fabrics ◽  
Process Conditions ◽  
University Of Tennessee ◽  
Structures And Properties ◽  
Film Forming ◽  
Warfare Agents ◽  
The University

The primary goal of this research was to determine optimum processing conditions to produce commercially acceptable melt blown (MB) thermoplastic polyurethane (TPU) non-woven fabrics. The 20-inch wide Accurate Products MB pilot line at the Textiles and Nonwovens Development Center (TANDEC), The University of Tennessee, Knoxville, was utilized for this study. MB TPU webs having small fiber diameters were obtained from film-forming and highly elastic fiber-forming TPUs and the webs were mechanically strong and durable to abrasion compared to MB PP. The basic MB process was found to be fundamentally valid for the MB TPU process; however, the MB process was more complicated for TPU than PP, because web structures and properties of MB TPUs are very sensitive to MB process conditions. Furthermore, different TPU polymers responded very differently to MB processing and exhibited different web structure and properties, although uniform elastic MB webs were produced with average fiber diameters as small as 5.0μm. Preliminary research leading to this study was funded the Army Research Office (ARO) and the findings were used by ARO towards the development of an elastic chemical protective liner with better overall comfort attributes and protection against chemical warfare agents.

Influence of substrate films for photo spacer elastic recovery rate

2020 ◽  
Vol 35 (12) ◽  
pp. 1240-1247
Author(s):  
Hu ZOU ◽  
◽  
Hao ZHANG ◽  
Xiang HUANG ◽  
Hai-bing YIN
Keyword(s):  
Recovery Rate ◽  
Elastic Recovery ◽  
Influence Of Substrate
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