Thermal properties of polyurethane elastomer with different flexible molecular chain based on para-phenylene diisocyanate

Lei, Wanqing; Fang, Changqing; Zhou, Xing; Li, Jiabin; Yang, Rong; Zhang, Zisen; Liu, Donghong

doi:10.1016/j.jmst.2017.05.014

Cited by 45 publications

(16 citation statements)

References 60 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…When it comes to SS, as this is composed by macrodiol, which is typically the weakest link in the oxidation of PU elastomers, using macrodiols that have high oxidative stability could give PUs with better thermo-oxidative stability. A lower flexibility in chains of SS domains produced a lower thermal resistance threshold (temperature where 5% sample weight is lost) as a result of lower crystallinity [17]. The structure of the HS has more influence on thermal stability rather than SS structure.…”

Section: Effect Of Structure On Pu Thermal Resistancementioning

confidence: 99%

Thermal Resistance Properties of Polyurethanes and Its Composites

Amado¹

2020

Thermosoftening Plastics

View full text Add to dashboard Cite

The nature of starting materials and the condition of polyurethane (PU) preparation are regarded as the main general parameters that determine PU thermal resistance. The effect of structure and presence of additives were identified as the major general factors on this regard. Structural factors include phase microstructure, i.e., chemical structure, proportion, and segregation of soft and hard segments, polyol type (petrochemical or natural oil-based), isocyanate and chain extender type, and thermoplasticity of PU. In respect to the effect of additives, the incorporation of fillers is the most direct strategy to increase PU heat resistance. With respect to fiber additives, in general a positive effect is found on improving thermal resistance, although this generalization could not apply, considering the large number of different PU and environmental conditions of usage.

show abstract

Section: Effect Of Structure On Pu Thermal Resistancementioning

confidence: 99%

Thermal Resistance Properties of Polyurethanes and Its Composites

Amado¹

2020

Thermosoftening Plastics

View full text Add to dashboard Cite

show abstract

“…Polyurethane (PU) has excellent adhesion, low-temperature resistance, high elasticity, vibration damping and toughness, etc. [4,5]. Its molecular chain is composed of a soft segment and hard segment.…”

Section: Introductionmentioning

confidence: 99%

“…PU can be prepared by adjusting the ratio of the hard segment and soft segment due to its excellent comprehensive performance. The soft segment endows the material with better characteristics of being easy to stretch and retract, while the hard segment endows the material with good resilience and strength [4,6]. In order to improve the low intrinsic thermal conductivity of polyurethane (~0.20 W/m K), certain thermal conductivity filler is usually considered to put into polyurethane to improve thermal conductivity [5,7].…”

Section: Introductionmentioning

confidence: 99%

Polydopamine-Modified Al2O3/Polyurethane Composites with Largely Improved Thermal and Mechanical Properties

et al. 2020

Materials

View full text Add to dashboard Cite

Alumina/polyurethane composites were prepared via in situ polymerization and used as thermal interface materials (TIMs). The surface of alumina particles was modified using polydopamine (PDA) and then evaluated via Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TG), and Raman spectroscopy (Raman). Scanning electron microscope (SEM) images showed that PDA-Al 2 O 3 has better dispersion in a polyurethane (PU) matrix than Al 2 O 3 . Compared with pure PU, the 30 wt% PDA-Al 2 O 3 /PU had 95% more Young's modulus, 128% more tensile strength, and 76% more elongation at break than the pure PU. Dynamic mechanical analysis (DMA) results showed that the storage modulus of the 30 wt% PDA-Al 2 O 3 /PU composite improved, and the glass transition temperature (Tg) shifted to higher temperatures. The thermal conductivity of the 30 wt% PDA-Al 2 O 3 /PU composite increased by 138%. Therefore, the results showed that the prepared PDA-coated alumina can simultaneously improve both the mechanical properties and thermal conductivity of PU. ceramic fillers, spherical Al 2 O 3 has often been used as electronic packaging materials because it exhibits higher thermal conductivity (32 W/m K), easier surface modification, wider source, higher load, lower viscosity, better fluidity, and excellent insulation performance [19,20]. Alumina as a thermal conductivity filler to enhance the thermal conductivity of polymers has been widely examined by many researchers [21][22][23].In general, the high thermal conductivity of polymer composites mainly depends on whether the filler has a good thermal conduction path or network, which is mainly related to the interfacial interaction and dispersion of the filler in polymers matrix [7,[24][25][26]. Generally speaking, poor interface combination between a thermal conductivity filler and polymer matrix leads to poor dispersion of the filler. These all cause strong phonon scattering and reduce phonon transmission efficiency, and then lead to the poor thermal conductivity of the interface [12,18,20,27,28]. It is reported that surface modification and functionalization of the filler can improve compatibility with the polymer matrix [29,30]. Common surface modification methods are hydroxylation [31], surfactant [32], coupling agent [27,33], etc. In recent years, bio-activated modification of polydopamine has become popular as a simple, environmentally-friendly, and efficient method. Polydopamine (PDA) is easy to adhere to the surface of inorganic and organic materials, and the abundant phenolic hydroxyl groups on the surface of polydopamine are conducive to the formation of stronger interaction with the resin matrix [9,13,17,34]. In this study, the surface of spherical Al 2 O 3 was modified using polydopamine as a modifier. In order to realize insulating composites with high thermal conductivity and mechanical properties, a high load of spherical Al 2 O 3 particles are required. However, if the filler cannot be uniformly dispersed in the matrix and has good compatibility with the ma...

show abstract

“…Dynamic mechanical analysis (DMA) and differential scanning calorimetry (DSC) are often utilized to study the viscoelastic and thermal properties of polyurethane elastomers with different shapes. But most researchers use them to study the crystallization, melting transition, glass‐transition temperature, and microphase separation of polyurethane . Bhat et al .…”

Section: Introductionmentioning

confidence: 99%

“…analyzed the polymer macromolecular structure by DMA to understand the regular arrangement of polymeric materials. Lei et al . explored the thermal properties of the polyurethane elastomer with DSC, thermogravimetric analysis, and DMA, which indicated that the impossibility of chains tightly packing and crystalline domains forming resulted from the decreasing flexibility of molecular chains.…”

Section: Introductionmentioning

confidence: 99%

Dynamic viscoelasticity of PUF under small strain and prediction of dynamic viscoelasticity in a wide frequency range

You

Wang

Shuqin

et al. 2018

J of Applied Polymer Sci

View full text Add to dashboard Cite

The dynamic viscoelasticity of polyurethane fiber (PUF) under small strain was studied with dynamic mechanical analysis and differential scanning calorimetry, and its viscoelasticity was predicted in a wide frequency range. The results revealed that the loss factor (tan δ) was about 0.05 and the phase angle (δ) was 2.86 , very close to the δ of a perfect elastomer in the range from −100 C to −80 C. The master curves superimposed by time-temperature superposition (TTS), the frequency range of the storage modulus master curve spanned 17 orders of magnitude from 10 −7 Hz to 10 10 Hz, and the loss modulus master curve spanned 13 orders of magnitude from 10 −3 Hz to 10 10 Hz. The apparent activation energy of the soft segment relaxation decreased with increasing temperature in the range from −70 to −26 C.

show abstract

Thermal properties of polyurethane elastomer with different flexible molecular chain based on para-phenylene diisocyanate

Cited by 45 publications

References 60 publications

Thermal Resistance Properties of Polyurethanes and Its Composites

Thermal Resistance Properties of Polyurethanes and Its Composites

Polydopamine-Modified Al2O3/Polyurethane Composites with Largely Improved Thermal and Mechanical Properties

Dynamic viscoelasticity of PUF under small strain and prediction of dynamic viscoelasticity in a wide frequency range

Contact Info

Product

Resources

About