TPU nanocomposites tailored by graphene nanoplatelets: the investigation of dispersion approaches and annealing treatment on thermal and mechanical properties
“…11,14,48 It is clearly seen that the pristine graphite records a two intense diffraction peaks located at 26.52˚ and 54.64˚ which are approximately compatible with its value of the first and third peaks of MWCNTs with approximately similar interlayer spacing and basal plane. 17,23,49 Figure 4.XRD diffraction of pristine multi-walled carbon nanotubes compared to Graphite.…”
Section: Resultsmentioning
confidence: 99%
“…14,15 Polyurethanes are di-block copolymers consisting of hard and soft phases. 16,17 The hard phase is formed from a diisocyanate and a chain extender, while the soft segment is made from polyether or ester-based polyols. However, immiscibility between the hard and soft domains leads to a structural phenomenon called a microphase-separated structure.…”
This study focusses on the effect of the addition of multi-walled carbon nanotubes (MWCNTs) on the morphology and thermal, rheological and electrical properties of hard copolymer polyurethane (HCPU) using 1,5 pentane-diols as a chain extender, containing 85% of hard segment blocks. Step-growth polymerisation was used to synthesise a HCPU polymer matrix, followed by melt compounding to prepare the nanocomposites. SEM investigation of the neat HCPU structure and its nanocomposites indicated the uniform dispersion of MWCNTs within the polymer matrix; further TEM morphology investigation showed some agglomeration regions, attributed to the high MWCNT content (2 wt%). An XRD test confirmed a homogeneous distribution of MWCNTs by observing the remaining location of the highest peaks of MWCNTs and amorphous peaks of the HCPU matrix. Analysis of the melt rheology test results showed an improvement in complex viscosity combined with an increase in the G’ and G” of nanocomposites from those of pure HCPU due to the presence of MWCNTs. Finally, electrical conductivity of nanocomposites demonstrated a significant improvement in its value at high loading of MWCNTs from that of pure HCPU matrix.
“…11,14,48 It is clearly seen that the pristine graphite records a two intense diffraction peaks located at 26.52˚ and 54.64˚ which are approximately compatible with its value of the first and third peaks of MWCNTs with approximately similar interlayer spacing and basal plane. 17,23,49 Figure 4.XRD diffraction of pristine multi-walled carbon nanotubes compared to Graphite.…”
Section: Resultsmentioning
confidence: 99%
“…14,15 Polyurethanes are di-block copolymers consisting of hard and soft phases. 16,17 The hard phase is formed from a diisocyanate and a chain extender, while the soft segment is made from polyether or ester-based polyols. However, immiscibility between the hard and soft domains leads to a structural phenomenon called a microphase-separated structure.…”
This study focusses on the effect of the addition of multi-walled carbon nanotubes (MWCNTs) on the morphology and thermal, rheological and electrical properties of hard copolymer polyurethane (HCPU) using 1,5 pentane-diols as a chain extender, containing 85% of hard segment blocks. Step-growth polymerisation was used to synthesise a HCPU polymer matrix, followed by melt compounding to prepare the nanocomposites. SEM investigation of the neat HCPU structure and its nanocomposites indicated the uniform dispersion of MWCNTs within the polymer matrix; further TEM morphology investigation showed some agglomeration regions, attributed to the high MWCNT content (2 wt%). An XRD test confirmed a homogeneous distribution of MWCNTs by observing the remaining location of the highest peaks of MWCNTs and amorphous peaks of the HCPU matrix. Analysis of the melt rheology test results showed an improvement in complex viscosity combined with an increase in the G’ and G” of nanocomposites from those of pure HCPU due to the presence of MWCNTs. Finally, electrical conductivity of nanocomposites demonstrated a significant improvement in its value at high loading of MWCNTs from that of pure HCPU matrix.
“…In fact, this phenomenon relies on several factors, such as the chemical structure and composition of the PUC, the conditions of synthesis process and the system thermodynamics, and so on. [39][40][41] At room temperature, soft domains are at above their glass transition temperature while, hard domains are below their glass temperature. Therefore, this property of the soft domains make polymer to behave as rubber-like behaviour, in contract the hard domain acting as physical crosslinkers.…”
Section: Introductionmentioning
confidence: 99%
“…45,46 There are many common techniques to disperse nanofillers within polymer matrices. 41,47 The melt processing technique is one of the most popular methods utilised to obtain better dispersion/mixing of nano-scale fillers based polymeric materials, while also cost effectiveness and flexibility can be taken into consideration, is the melt processing technique. 48,49 Nanoclay as nanofiller is a successful agent in improving polyurethane properties such as mechanical properties, 50 thermal stability 51 and barrier property.…”
Section: Introductionmentioning
confidence: 99%
“…Microphase-separated structure of PUC can be extensively affected by thermal treatment (annealing treatment process). 41 Although many reports from literatures studied the relationship between microphase separation and annealing process of neat polyurethane, [55][56][57] there has yet to be undertaken a comprehensive investigation on the microphase-separated PU/MMT nanocomposites correlation to thermal treatment process. One study by Anandhan et al 53 showed that a reduction in performance of PU/ MMT nanocomposites was due to the potential hindrance in microphase-separated morphology.…”
This study focuses on a new fabrication of nanocomposite based on Polyurethane Copolymer (PUC) intercalated with organo-modified montmorillonite nanoparticles (OMMT), via an efficient combination of solution mixing and melt blending processes. The combination of solution mixing and melt interaction processes produced PUC/OMMT nanocomposites with enhanced properties. The OMMT filled PUC was characterised by TEM and tensile test. The effect of thermal treatment process was also studied due to subsequent microphase separation of PUC resulting from microdomain miscibility. TEM observation recognised a decent dispersion state of OMMT within PUC, owing to their exfoliated and intercalated structure. This morphology was greatly influenced by induced thermal treatment. The dynamic mechanical thermal analysis (DMTA) revealed that storage modulus and glass transition temperature of the nanocomposites increased with OMMT incorporation. The tensile modulus and tensile strength of nanocomposites showed an improvement with the addition of OMMT.
Improving the performance of polyurethane is a crucial endeavor due to its versatile properties that make it suitable for various uses, especially as a matrix in the field of composite materials. The current work investigates the influence of the addition of two types of graphene derivatives, graphene oxide (GO) and reduced graphene oxide (rGO), to hard copolymer polyurethane (HCPU). HCPUs as nanocomposites were synthesized using melt‐mixing approaches with different weight ratios of nanofiller additives. The transmission electron microscopy and scanning electron microscopy displayed the morphology through the incorporation of nanofillers within the HCPU structure. Thermogravimetric analysis (TGA) testing showed an increase in the thermal stability of HCPU with the addition of GO and rGO. Herein, the overall HCPU crystallinity/microphase separation decreased after the addition of GO and rGO compared to unfilled HCPU samples. The thermal stability test showed significant enhancement with increasing GO and rGO incorporated weight ratio due to the barrier and tortuous path effects of nanofillers. A clear increase in thermal and electrical conductivity is found, in particular at greater content of addition (5 wt%) of rGO in comparison with neat HCPU. The rheological behavior showed that the storage modulus of HCPU nanocomposites increased from that of pure HCPU, proving the formation of a filler‐polymer network interaction within the HCPU chain structure. Dispersion and physical and/or chemical interaction of the GO and rGO within polyurethane chains plays a major role in enhancing the morphology and thermal and rheological properties, and thus represents a significant improvement for the final properties of HCPU nanocomposites.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
