Property Optimisation of EPDM Rubber Composites Using Mathematical and Statistical Strategies

Table 4

Measured values of hardness (HD), tensile strength (TS), elongation at break (EB), rebound resilience (RS), and material costs (CT) for the nine designed mixtures in two replications.

Mixture		HD (Shore A)	TS (MPa)	EB (%)	RS (%)	Cost (US$/kg)
Replication 1	1	77.0 ± 0.7	12.5 ± 0.1	496.7 ± 08.2	27.8 ± 1.1	2.63
	2	70.8 ± 0.5	10.7 ± 0.2	588.0 ± 10.9	26.6 ± 0.6	2.55
	3	59.4 ± 0.6	11.2 ± 0.6	670.0 ± 11.6	26.8 ± 0.5	2.47
	4	79.0 ± 0.0	9.5 ± 0.2	453.3 ± 10.3	25.0 ± 0.7	2.22
	5	70.0 ± 0.7	9.0 ± 0.2	550.0 ± 10.0	24.4 ± 0.6	2.17
	6	61.4 ± 0.6	8.7 ± 0.2	636.0 ± 08.9	26.4 ± 0.6	2.11
	7	80.8 ± 0.5	8.1 ± 0.2	403.3 ± 08.2	22.6 ± 0.9	1.91
	8	72.4 ± 0.9	7.2 ± 0.2	468.0 ± 10.9	23.8 ± 0.5	1.89
	9	65.2 ± 1.3	7.4 ± 0.2	565.0 ± 10.5	24.6 ± 0.6	1.87
Replication 2	1	79.8 ± 0.5	11.6 ± 1.8	496.6 ± 08.2	29.6 ± 0.9	—
	2	70.8 ± 0.8	11.8 ± 0.4	552.0 ± 10.6	26.0 ± 0.0	—
	3	63.4 ± 0.9	11.1 ± 0.4	670.0 ± 11.6	29.0 ± 1.2	—
	4	82.4 ± 1.1	9.3 ± 0.2	436.0 ± 08.9	25.2 ± 1.1	—
	5	76.4 ± 0.9	9.6 ± 0.2	512.5 ± 09.6	26.2 ± 0.5	—
	6	61.2 ± 0.8	9.0 ± 0.2	647.5 ± 09.6	26.6 ± 0.6	—
	7	73.0 ± 0.7	8.8 ± 0.2	470.0 ± 11.6		—
	8	73.0 ± 1.2	7.5 ± 0.2	486.6 ± 10.3	25.2 ± 0.5	—
	9	75.6 ± 0.6	7.4 ± 0.2	566.7 ± 10.3	22.6 ± 0.6	—

Value could not be measured.