Gravity Effects of Curing Angle on Laminated Composite Structures: A Review on Novel Study

Table 1

Density, viscosity, advantages, and disadvantages of epoxy and unsaturated polyester.

Matrix	Epoxy	Unsaturated polyester
Density (kg/m^3)	1100 [12]	1100–1400 [49]
	1100–1350 [50]	1200 [51]
	1200–1300 [49]	1400 [50]
Viscosity (Pa·s) at 25°C	0.15 [52, 53]	0.4 [54]
	0.3 [53]; 9–17 [55]	0.764 (20°C) [56]
	10–15 [57]	0.3–0.4 [58]
Advantage	Lower shrinkage [15, 28]	Low viscosity [59, 60]
	Lower residual stress [28]	Short curing time [59, 60]
	Wide selection of curing agent with good control in the degree of cross-linking [15, 28]	Low cost [59, 60]
Disadvantage	Brittle [28, 30]	Poor resistance to acids [60]
	Poor resistance to crack propagation/low fracture toughness [15, 61]	Low fiber/matrix bond strength [60]