Stereocomplex crystallization of high-molecular-weight poly(l
Due to the enhanced sc crystallization, storage modulus of HMW PLLA/PDLA blend at high temperatures (170–200 °C) increases significantly after the addition of PPZn. The nucleator-promoted sc crystallization of HMW PLLA/PDLA blend is attributed to the improved PLLA/PDLA intermolecular interactions and lattice matching
Investigation into the effects of fillers in polymer processing
The Young''s modulus of amorphous materials was strongly affected by the filler content, while crystalline materials were not that sensitive to the filler content/level. The Young''s modulus of polystyrene-based polymer nanocomposites (PNCs) with 8 wt% fillers at 200 °C and 50 rpm was found to be of approximately 1786 MPa.
Rheology of vitrimers | Nature Communications
Rheology studies on vitrimers have mostly focused on their linear viscoelasticity under small deformations. Here, the authors develop a full rheological understanding of vitrimer response that
Fibrosis mechanism, crystallization behavior and mechanical properties
Storage modulus represents the energy stored by elastic deformation and reflect the ability of materials to resist deformation [54]. PP/PTFE MFC had higher storage modulus than pure PP especially when the temperature was below T g, which is originated from the discrepancy between their crystal structure.
Enhanced crystallization and storage stability of
With only 0.75 wt% HC 8, the crystallization half-life time t 1/2 of PHA at 100 °C decreased by 91 % and the degree of crystallinity increased to 38.2 % with a large number of tiny nuclei. Moreover, storage stability of mechanical properties of PHA was greatly improved due to the better crystallization ability.
Glass transition temperature from the chemical structure of
At higher temperatures, the storage modulus decreases orders of magnitude to ~10 MPa for a semicrystalline polymer, or ~1 MPa for an entangled
The influence of nucleating agents, plasticizers, and molding
The crystallization half-time of PLA can decrease dramatically to a minute or even below when an effective nucleating agent is used [11], [12], [24]. We measured the storage modulus of the specimens with a Dynamic Mechanical Analyzer (DMA) Q800 (TA Instruments, New Castle, USA). We investigated the storage modulus in the
A novel approach to the study of extensional flow-induced
A characterization of the crystallization induced by extensional flow is presented. The crystallization of P P under quiescent condition and after pre-shear are
Investigation of Dynamic, Mechanical, and Thermal Properties of
The storage modulus of the PLA/CP composites was found to increase after ca.85°C, except for the neat PLA, which was due to the cold crystallization of the PLA/CP composites. In general, cold crystallization occurs when the polymer chain gains sufficient mobility to arrange itself into an ordered structure (i.e., crystalline structure) due
Relationship between the Stereocomplex Crystallization Behavior
Apparently, storage modulus is not determined solely by the content of the PDLA, so the propensity of PDLA was also determined to reduce the crystallinity of PLLA. As expected, the E'' plot also highlights the fact that the PLLA/PDLA blends have a higher E'' than neat PLLA and PDLA at 20 °C, indicating an increased stiffness and the E''
The influence of nucleating agents, plasticizers, and molding
When these specimens were heated above 75 C, cold crystallization started, which caused the storage modulus to increase until the specimens reached maximum possible crystallinity around 90 C. Above this temperature, the storage modulus monotonously decreased, and finally, this decrease became more and more
Structure, Mechanical and Thermal Properties of Polyphenylene
The storage modulus starts to increase again at temperatures around 125 C, which is the result of cold crystallization of the PPS matrix. For the PSU-based composites, the plateau of the storage modulus for all the composites was observed up to a glass transition temperature of the PSU.
Thermal, rheological, and mechanical properties of cellulose
The storage modulus of PHBH/CNF increased by two or three orders of magnitude higher than that of PHBH at 180 C at 10 rad/s. Fig. 6 Frequency sweep test at 180 (^circ{rm C}) with different contents of CNF, a storage modulus, b loss modulus, c complex viscosity; d Temperature sweep test with different contents of CNF
Dynamic Mechanical Analysis in the Analysis of
Above the T g, the storage modulus tends to be fairly flat with a slight increase with increasing frequency as it is on the rubbery plateau. The change in the region of a transition is greater. If one can
Superior Impact Toughness and Excellent Storage Modulus of
The foams present superior impact toughness which is 6-fold higher than that of neat PLA, and no significant decrease was observed for the storage modulus. Moreover, SC−CO 2 LTFP at soaking temperature ranging from 110 to 150 °C were performed to determine the evolution of pore morphology. The ultratough and supermoduli are unprecedented for
Crystallization temperature dependence of hardness and energy storage
The effect of crystallization on the mechanical properties (hardness, modulus of elasticity and fracture toughness) of lithium disilicate Li2O.2SiO2 glass-ceramic was investigated by indentation
Development of in-situ nanofibrillated poly(butylene succinate)/polytetrafluoroethylene composites with elevated rheology, crystallization
The relaxation time was prolonged by PTFE fibrils, resulting in an enhancement in storage modulus and melt viscosity. Differential scanning calorimetry was used to study the non-isothermal crystallization kinetics at different cooling rates.
Crystallization, rheological and mechanical properties of poly
It can be seen from Fig. 2b that the highest storage modulus of neat PBS was 3.7 GPa, and the storage modulus dropped sharply at about ‒30 °C because the glass transition began to occur. PPC and PVAc showed the highest storage modulus of 1.7 and 3.2 GPa, respectively, at temperature below their T g s. When the glass transitions of
Relationship between Structure and Rheology of Hydrogels for
The crystallization commenced once the hydrogel was immersed into an aqueous NaCl solution, which increased its mechanical strength . However, the slope of the storage modulus is steeper, which eventually leads to the two values crossing and the occurrence of the gel-sol transition. The crossover point is different for the hydrogels
Crystallization and Performance Evolution of PHBV
1 · Notably, the dynamic storage modulus (G''), and complex viscosity (η*) of PHBV nanocomposites exhibit a clear decrease in the whole frequency range. As depicted in Figure 5 (a), the G′ of nanocomposite samples are both lower across the entire frequency range than those of the neat PHBV under the 1 wt.% loading condition.
Effect of thermal aging on crystallization behaviors and
tain an idea about the storage modulus, loss modulus and damping behavior. Yang et al. [29] prepared PPS/multiwall carbon nanotube composites and observed increased Tg and storage modulus of PPS via DMA. Wu et al. [30] studied thermal behaviors and viscoelastic properties of PPS/epoxy resin by DMA test and showed that the epoxy resin can pro-
Thermomechanical behavior of aerospace-grade RTV (silicone
Tensile modulus measurements plotted in Fig. 9, Fig. 10 indicate that RTV 566 material that is premixed and frozen in the uncured state, then cured after an extended period of time has a greater capacity to undergo crystallization than does material that is mixed and immediately cured. A plausible explanation for this behavior is that storing
Rheology of vitrimers | Nature Communications
The first two curves show the storage modulus of the Leibler''s benchmark epoxy vitrimer (at two frequencies of small oscillation), which shows the glass transition and the rubber modulus at
The Influence of the Degree of Crystallinity on the Elasticity Modulus
The lower crystallinity also affects the potential amount of stored energy in the systems [47], which results in a decreased storage modulus between T β and T m for polymers with higher HEMA
The low temperature crystallization of hydrogenated nitrile butadiene
The shear storage modulus (G′) and shear loss modulus (G″) data were collected at 5 min intervals over a period of approximately 8 h, although not all data points are presented here. Crystallization in a representative HNBR after exposure to low temperatures has been detected and reported here. This crystallization is believed to
Basic principle and good practices of rheology for
The physical meaning of the storage modulus, G '' and the loss modulus, G″ is visualized in Figures 3 and 4. The specimen deforms reversibly and rebounces so that a significant of energy is recovered ( G′ ), while the
Investigation of Dynamic, Mechanical, and Thermal Properties of Calotropis procera Particle-Reinforced PLA Biocomposites
The storage modulus of the PLA/CP composites was found to increase after ca.85 C, except for the neat PLA, which was due to the cold crystallization of the PLA/CP composites. In general, cold crystallization occurs when the polymer chain gains sufficient mobility to arrange itself into an ordered structure (i.e., crystalline structure)
Effect of thermal aging on crystallization behaviors and dynamic
tain an idea about the storage modulus, loss modulus and damping behavior. Yang et al. [29] prepared PPS/multiwall carbon nanotube composites and observed increased Tg and storage modulus of PPS via DMA. Wu et al. [30] studied thermal behaviors and
Dynamic Mechanical Analysis in the Analysis of
This crystallization occurs when the polymer chains have been quenched (quickly cooled) into a highly disordered state. The storage modulus'' change with frequency depends on the transitions
An elastomer with ultrahigh strain-induced crystallization
Strain-induced crystallization (SIC) prevalently strengthens, toughens, and enables an elastocaloric effect in elastomers. However, the crystallinity induced by mechanical stretching in common elastomers (e.g., natural rubber) is typically below 20%, and the stretchability plateaus due to trapped entanglements.
Modelling sugar, processing, and storage effects on palm oil
The higher saturated and partial acylglycerol content of palm oil compared to the mid-fraction enhanced the extent of crystallization, storage modulus, and firmness. Cooling endpoint temperature also impacted solid fat content, viscoelasticity, and showed significant interactions with both palm oil type and confectioner''s sugar.
Rheological properties of rotator and crystalline phases of
The obtained results show that the storage and loss moduli of the rotator phases are ca. 10-times lower than those of the respective crystalline phases. We found also that the rheological properties of the crystal phases depend mainly on the subcooling temperature below the crystallization temperature, T C, while the R phases become
Shear-induced enhancements of crystallization kinetics
The evolutions of storage modulus, G′ during isothermal crystallization for linear PLA and LCB PLAs at 130 °C under the
Crystallization and Mechanical Properties of Polypropylene under
As parameters, the secant modulus (ranging from 2 to 10 N/mm 2) and the yield stress were determined with 5 test samples. To determine the storage
Modelling sugar, processing, and storage effects on palm oil crystallization
Storage (G′) and loss (G″) moduli were measured to determine the effects of φ and T e on the crystal growth and network formation of stored samples (Omar, Let, Seng, & Rashid, 2005). This was achieved by performing frequency sweep tests at 0.01% strain [21 points of angular frequency (ω) were collected between 4 and 63 rad s −1 ].
سابق：coil spring energy storage power generation
التالي：mobile energy storage distribution network
