Understanding phase separation and morphology in thermoplastic polyurethanes nanocomposites

Pedrazzoli, Diego; Manas‐Zloczower, Ica

doi:10.1016/j.polymer.2016.03.022

Cited by 75 publications

(51 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The strong p-p interactions and large Van der Waals forces between GNPs can cause their aggregation and stacking in nanocomposites. However, the long MWCNTs acting like arms and bridging GNPs may inhibit their aggregation, thus creating a strong inter-connected hybrid nanofiller network in the polymer matrix [40], as described in the recent literature for thermoplastic and thermosetting matrices incorporating different hybrid fillers [41][42][43].…”

Section: Effect Of Filler Concentration and Combinations Of Nanofillementioning

confidence: 99%

PLA/Graphene/MWCNT Composites with Improved Electrical and Thermal Properties Suitable for FDM 3D Printing Applications

et al. 2019

View full text Add to dashboard Cite

In this study, the structure, electrical and thermal properties of ten polymer compositions based on polylactic acid (PLA), low-cost industrial graphene nanoplates (GNP) and multi-walled carbon nanotubes (MWCNT) in mono-filler PLA/MWCNT and PLA/GNP systems with 0–6 wt.% filler content were investigated. Filler dispersion was further improved by combining these two carbon nanofillers with different geometric shapes and aspect ratios in hybrid bi-filler nanocomposites. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman spectroscopy exhibited uniform dispersion of nanoparticles in a polymer matrix. The obtained results have shown that for the mono-filler systems with MWCNT or GNP, the electrical conductivity increased with decades. Moreover, a small synergistic effect was observed in the GNP/MWCNT/PLA bi-filler hybrid composites when combining GNP and CNT at a ratio of 3% GNP/3% CNT and 1.5% GNP:4.5% CNT, showing higher electrical conductivity with respect to the systems incorporating individual CNTs and GNPs at the same overall filler concentration. This improvement was attributed to the interaction between CNTs and GNPs limiting GNP aggregation and bridging adjacent graphene platelets thus, forming a more efficient network. Thermal conductivity increases with higher filler content; this effect was more pronounced for the mono-filler composites based on PLA and GNP due to the ability of graphene to better transfer the heat. Morphological analysis carried out by electron microscopy (SEM, TEM) and Raman indicated that the nanocomposites present smaller and more homogeneous filler aggregates. The well-dispersed nanofillers also lead to a microstructure which is able to better enhance the electron and heat transfer and maximize the electrical and thermal properties. The obtained composites are suitable for the production of a multifunctional filament with improved electrical and thermal properties for different fused deposition modelling (FDM) 3D printing applications and also present a low production cost, which could potentially increase the competitiveness of this promising market niche.

show abstract

Section: Effect Of Filler Concentration and Combinations Of Nanofillementioning

confidence: 99%

PLA/Graphene/MWCNT Composites with Improved Electrical and Thermal Properties Suitable for FDM 3D Printing Applications

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Thermoplastic polyurethane (TPU) films have been used widely in many fields, such as electronics, medical treatment, food and other industries. This is largely due to their excellent comprehensive properties, such as high strength, high toughness, abrasion resistance and oil resistance, and good processing performance [1][2][3][4]. However, they are susceptible to failure arising from micro-cracks generated on the surface and inside inner layer during processing and utilization, which lead to a sharp decrease in their sustainability, safety, and lifetime [5][6][7][8][9].…”

Section: Introductionmentioning

confidence: 99%

Electrical and Thermal and Self-Healing Properties of Graphene-Thermopolyurethane Flexible Conductive Films

et al. 2020

View full text Add to dashboard Cite

We fabricated graphene-thermopolyurethane (G-TPU) flexible conductive film by a blending method and systematically investigated the electrical, thermal and self-healing properties of the G-TPU flexible conductive film by infrared light and electricity. The experimental results demonstrate that the G-TPU composite films have good conductivity and thermal conductivity in the appropriate mass content of graphene in the composite film. The composite films have the good electro-thermal and infrared light thermal response performances and electro-thermal response performance is closely related to the mass content of graphene in the composite film, but the infrared light thermal response performance is not. The scratch on the composite film can be completely healed, using electricity or infrared light. The healing efficiency of the composite film healed using infrared light is higher than that of using the electricity, while the healing time of the composite film is shorter. Regardless of the self-healing method, the temperature of the self-healing is a very important factor. The self-healing conductive composite film still exhibits a good conductivity.Nanomaterials 2020, 10, 753 2 of 16 of the material can be automatically healed to improve the safety, lifetime, and environmental impact of man-made materials [16][17][18][19][20][21]. To obtain self-healing materials, many strategies have been explored, such as micro-containers containing healing agent and microvascular networks in the matrix, dynamic chemical bonds or weak interaction [22][23][24][25][26][27]. These self-healing materials can realize self-healing by using a large number of healing agents [28,29]. In theory, they can realize multiple self-healing of the damaged materials with the assistance of external light, heat, and electric field, et al. Although, great progress has been made in the research of the self-healing materials and techniques, there are still some critical problems that restrict their applications, such as low mechanical properties after healing, high cost, time-consuming, and low efficiency. Therefore, it is significant to fabricate a self-healing polymer and composites based on new materials, and then explore their potential applications, as well as new healing method.Graphene (G), a novel two-dimensional material, possesses large specific surface area, superior mechanical property, as well as being an excellent conductor of both heat and electricity, and having a good microwave and infrared absorbing capacity, so they have strong response to electricity and electromagnetic waves and infrared radiation (IR) [30][31][32][33][34]. Graphene is often used as fillers in preparing functional composites. Based on these properties, researchers fabricated graphene-based self-healing polymer composites by introducing graphene into the polymer [34,35]. Kim et al. reported, for the first time, self-healable PU nanocomposites, containing modified graphene by the near IR absorption of graphene [36]. Huang et al. prepared TPU containing few layers of g...

show abstract

“…soft segment molecular weight [1,2], diisocyanate symmetry [3,4], ability Hydrogen bonding ability [5] and the methods for synthesizing and processing polyurethane [6][7][8][9] are some factors that affected phase separation [10]. Peddrzoli et al [11] found that carbon nanotubes are effective in the hard and soft phase of the polyurethane morphology, and their combination with cellulosic nanocrystals can have the greatest effect.…”

Section: Introductionmentioning

confidence: 99%

Role of sequence of feeding on the properties of polyurethane nanocomposite containing halloysite nanotubes

Oliaie

Haddadi‐Asl

Mirhosseini

et al. 2019

Designed Monomers and Polymers

View full text Add to dashboard Cite

Polyurethane/Halloysite Nantubes nanocomposites containing 1 wt.% nanoparticles were prepared using in situ polymerization method with different mixing sequences. Various experiments have been performed in order to evaluate the effect of nanoparticle dispersion and the different orders of mixing of the samples on the mechanical properties and morphology of nanocomposites. The results obtained from the ATR-FTIR test demonstrated that the presence of nanoparticles led to an increase in phase separation, and the sample with the best nanoparticle dispersion has shown more phase separation than the other samples. Furthermore, the results of the Differential scanning calorimetry (DSC) also confirmed more phase separation and the crystallinity of the samples in the presence of nanoparticles. Scanning electron microscope (SEM) images were utilized in order to investigate the dispersion of nanoparticles in polyurethane matrix and to examine surface fracture of the samples. Moreover, differential mechanical thermal analysis (DMTA) revealed that the presence of nanoparticles has altered the glass transition temperature of polymers, and there are physical and chemical interaction and hydrogen bonding between nanoparticles and hard and soft polyurethane segments. In addition, in the presence of nanoparticles the damping of the samples was reduced compared to the neat sample. Change in behavior from liquid like to solid like in the range of low angular frequencies was observed which is in agreement with the formation of a network structure that can be broken even at low shear rates. In the second step, kinetics of the phase separation process of thermoplastic polyurethane and nanocomposites was studied by rheological experiments. The results showed that the kinetics of phase separation process of thermoplastic polyurethane is similar to that of the crystallization process. Phase separation kinetics of neat samples and nanocomposite have been studied. The presence of nanoparticles by nucleation mechanism increased the rate of the phase separation.

show abstract

Understanding phase separation and morphology in thermoplastic polyurethanes nanocomposites

Cited by 75 publications

References 37 publications

PLA/Graphene/MWCNT Composites with Improved Electrical and Thermal Properties Suitable for FDM 3D Printing Applications

PLA/Graphene/MWCNT Composites with Improved Electrical and Thermal Properties Suitable for FDM 3D Printing Applications

Electrical and Thermal and Self-Healing Properties of Graphene-Thermopolyurethane Flexible Conductive Films

Role of sequence of feeding on the properties of polyurethane nanocomposite containing halloysite nanotubes

Contact Info

Product

Resources

About