Table 1.
Main experimental chemicals
| Experimental materials | Specification | The manufacturer |
|---|---|---|
| Graphite powder | Q/HG3991-88 | Tianjin Fengchuan Chemical Reagent Technology Co., Ltd |
| Graphene | 5~15μm | Tianjin Kairuisi Fine Chemical Co., Ltd |
| Silver-coated copper powder | P-30 | Shenzhen Changxinda Shielding Material Co., Ltd |
| Polyurethane | PU-2540 | Guangzhou Yuheng Environmental Protection Materials Co., Ltd |
| Thickener | 7011 | Guangzhou Dianmu Composite Materials Business Department |
| Slurry defoaming agent | 5020 | Jiangsu Hengyu Chemical Industry Group Co., Ltd |
Table 2.
Main test instruments
| The Instrument | Specification | The manufacturer |
|---|---|---|
| High-temperature blast drying oven | DGG-9148A | Shanghai Aozhen Instrument Manufacturing Co., Ltd |
| Coating machine | LTE | Werner Mathis, Switzerland |
| Digital viscometer | SNB-2 | Shanghai Hengping Instrument And Meter Factory |
| Digital fabric thickness gauge | YG141D | Laizhou Electronic Instrument Co., Ltd |
| Dielectric spectrometer | BDS50 | Novocontrol Gmbh, Germany |
| Vector network analyzer | ZNB40 | Rohde Schwarz, Germany |
Table 3.
Process parameters of different contents of functional particles
| Number | Content of functional particles (%) | Ratio of the graphite/graphene/silver-coated copper powder | Stirring time (min) | Viscosity (mPa·s) | Thickness (mm) | Drying temperature (°C) | Drying time (min) |
|---|---|---|---|---|---|---|---|
| 1 | 0 | 6:3:1 | 30 | 30000 | 1.0 | 80 | 30 |
| 2 | 12 | 6:3:1 | 30 | 30000 | 1.0 | 80 | 30 |
| 3 | 24 | 6:3:1 | 30 | 30000 | 1.0 | 80 | 30 |
| 4 | 36 | 6:3:1 | 30 | 30000 | 1.0 | 80 | 30 |
| 5 | 48 | 6:3:1 | 30 | 30000 | 1.0 | 80 | 30 |
| 6 | 60 | 6:3:1 | 30 | 30000 | 1.0 | 80 | 30 |
Fig. 1.
Influence of the content of functional particles on the real part of the dielectric constant of the single-layer coated composites
Fig. 2.
Influence of the content of functional particles on the imaginary part of single-layer coated composites
Fig. 3.
Influence of the content of functional particles on the loss tangent value of the single-layer coated composites
Fig. 4.
Influence of the content of functional particles on the reflection loss of the single-layer coated composites
Fig. 5.
Influence of the content of functional particles on the shielding effectiveness of the single-layer coated composites