Thermograms Of Fully Cured Polybenzoxazine Composites Case Study
FIGURE 18 DSC thermograms of fully cured polybenzoxazine composites: (●) heat-cured polybenzoxazine, (□) heat-cured 2wt% SiCw, (♦) heat-cured 4 wt.% SiCw, (▴) heat-cured 6 wt.% SiCw, (▾) microwave-cured 4 wt.% SiCw. Reprinted from Ref. [39]. Copyright (2014), with permission from Wiley InterScience.
FIGURE 19. SEM micrographs of fracture surface of SiCw-filled polybenzoxazine composites: (a) neat PBZ cured by heat, (b) 2 wt.% SiCw -filled PBZ cured by heat, (c) 4 wt.% SiCw -filled PBZ cured by heat, (d) 4 wt.% SiCw -filled PBZ cured by microwave. Reprinted from Ref. [39]. Copyright (2014), with permission from Wiley InterScience.
3.2.3 Poly(BA-m)/BN micro-composites
The heat dissipation problem in microelectronic packaging is becoming increasingly …show more content…
FIGURE 21 Effect of boron nitride contents on the specific heat capacity of its filled polybenzoxazine composites. Reprinted from Ref. [34]. Copyright (1999), with permission from Kluwer Academic Publishers.
FIGURE 22 Specific heat capacities in the temperature range between 0–80°C of neat polybenzoxazine and boron nitride. ○ – boron nitride, □ – polybenzoxazine. Reprinted from Ref. [34]. Copyright (1999), with permission from Kluwer Academic Publishers.
The results of maximum packing densities of four different grades of BN (HCPH, HCJ325, TS1890, and HCJ48) indicated that the particle size of BN has a significant influence on packing density of composite. The packing density of Poly(BA-m)/BN composite increased with the increasing of particle size of BN, and the maximum value was up to 88wt.% for composite filled with HCJ48 with 225 μm average particle size. High packing density is mainly ascribed to the large average particle dimension, low effective aspect ratio, and a bimodal particle size distribution of the used BN [57-59], which could rapidly increase the conductivity values beyond the percolation threshold, through conductive networks in the composite which fulfilled both the path dependent and bulk …show more content…
By increasing the BN content, the modulus of the composites were increased justifying the higher thermal conductivity values of these specimens because the heat conduction phenomena is better in a stiffer material (higher acoustic velocity). The modulus at room temperature of 85 wt.% exceeded 10 GPa, which is a very high value even comparable to fiber glass-reinforced phenolic laminates. In addition, all the storage moduli for the tested composite were not stable at the rubbery plateau (ca. 200 °C) due to the high performance properties of the poly(BA-m)
FIGURE 19. SEM micrographs of fracture surface of SiCw-filled polybenzoxazine composites: (a) neat PBZ cured by heat, (b) 2 wt.% SiCw -filled PBZ cured by heat, (c) 4 wt.% SiCw -filled PBZ cured by heat, (d) 4 wt.% SiCw -filled PBZ cured by microwave. Reprinted from Ref. [39]. Copyright (2014), with permission from Wiley InterScience.
3.2.3 Poly(BA-m)/BN micro-composites
The heat dissipation problem in microelectronic packaging is becoming increasingly …show more content…
FIGURE 21 Effect of boron nitride contents on the specific heat capacity of its filled polybenzoxazine composites. Reprinted from Ref. [34]. Copyright (1999), with permission from Kluwer Academic Publishers.
FIGURE 22 Specific heat capacities in the temperature range between 0–80°C of neat polybenzoxazine and boron nitride. ○ – boron nitride, □ – polybenzoxazine. Reprinted from Ref. [34]. Copyright (1999), with permission from Kluwer Academic Publishers.
The results of maximum packing densities of four different grades of BN (HCPH, HCJ325, TS1890, and HCJ48) indicated that the particle size of BN has a significant influence on packing density of composite. The packing density of Poly(BA-m)/BN composite increased with the increasing of particle size of BN, and the maximum value was up to 88wt.% for composite filled with HCJ48 with 225 μm average particle size. High packing density is mainly ascribed to the large average particle dimension, low effective aspect ratio, and a bimodal particle size distribution of the used BN [57-59], which could rapidly increase the conductivity values beyond the percolation threshold, through conductive networks in the composite which fulfilled both the path dependent and bulk …show more content…
By increasing the BN content, the modulus of the composites were increased justifying the higher thermal conductivity values of these specimens because the heat conduction phenomena is better in a stiffer material (higher acoustic velocity). The modulus at room temperature of 85 wt.% exceeded 10 GPa, which is a very high value even comparable to fiber glass-reinforced phenolic laminates. In addition, all the storage moduli for the tested composite were not stable at the rubbery plateau (ca. 200 °C) due to the high performance properties of the poly(BA-m)