In the range of 1 to 5 wt%, the change of thermal expansion rate is obvious. OICR-9429 cost Beyond 5 wt%, the increase of CNT content within the temperature range (30°C ~ 120°C) results in the absolute values of the thermal expansion

rate |ε| becoming gradually smaller and finally converging to a stable value when the CNT content reaches 10 wt%. Note that the thermal expansion rate is negative at 30°C. Figure 5 Relationship between CNT content and absolute value of thermal expansion rate of uni-directional CNT/epoxy nanocomposite. (Data of 30°C = Original data × (−2.5); data of 75°C = Original data × 8). Multi-directional models The ranges of temperature and CNT content in this case are identical to those mentioned above for the uni-directional models. The variation of thermal expansion properties of CNT/epoxy nanocomposites is shown in Figure 6 (CNT content from 1 to 5 wt%), in which the similar effects of temperature and CNT content are observed. In this figure, the thermal expansion rates increase linearly Temsirolimus datasheet as the temperature increases for all CNT contents. The temperature at zero thermal expansion rate (or no

thermal expansion/contraction) of the CNT/epoxy nanocomposites is approximately 62°C at any CNT loading, which is similar to that for the uni-directional model. With increasing content of CNT, the absolute value of thermal expansion rate decreases. Moreover, compared to the uni-directional nanocomposites (Figure 4), at high temperature, the difference in thermal expansion between low CNT content (1 wt%) and high CNT content (5 wt%) is much smaller in the multi-directional nanocomposites.

Figure 6 Thermal expansion rate of multi-directional CNT/epoxy nanocomposite by numerical simulation. By varying the CNT content from 1 to 15 wt%, the obtained results are shown in Cytidine deaminase Figure 7. In this figure, the thermal expansion rates vary nonlinearly with the CNT content. In the content range of 1 to 5 wt%, the change in thermal expansion rate is obvious. Beyond 5 wt% CNT, as the CNT content increases, the absolute value of the thermal expansion rate |ε| becomes smaller gradually. However, unlike the uni-directional nanocomposites (Figure 5), the thermal expansion rate of the multi-directional nanocomposites still decreases proportionally to the CNT content even when the CNT content is over 10 wt%. Figure 7 Relationship between CNT content and absolute value of thermal expansion rate of multi-directional CNT/epoxy nanocomposite. (Data of 30°C = Original data × (−2.5); data of 75°C = Original data × 8). Verification To verify the effectiveness of the above multi-scale numerical simulations, the following theoretical prediction and experimental measurements were carried out. Theoretical prediction The following assumptions are made to derive conventional micromechanics models for the coefficient of thermal expansion (CTE).