Composite Strength Test
MOR (N/mm2) MOE (N/mm2) SP (N/mm2) Hardness (HRB)
Phenol-formaldehyde 43.20 496.12 38.40 Brittle
H. sabdariffa-r-PF 69.99 614.40 57.60 67.00
Hs-g-poly(EA)-r-PF 82.04 898.56 74.24 75.00
Hs-g-poly(EA-co-BA)-r-PF 79.90 875.99 74.08 74.00
Hs-g-poly(EA-co-VA)-r-PF 71.96 689.80 60.56 70.00
where, -r-PF refers to reinforced Phenol-formaldehyde.
Table 7: MOR, MOE, SP and Hardness studies of graft copolymers reinforced P-F composite vis-à-vis P-F resin.