The remaining trace of water in the styrene
monomer, containing swollen transferred rubber particles for 24 h,
was eliminated by centrifuging as previously mentioned. The upper
styrene phase isolated and mixed with 1.0 wt% of benzoyl peroxide
(BPO; Sigma, microscope) was then poured into a Teflon coated
steel mould (10.4·10.4·2.6 cm3) and polymerised at 70 C in an
oven (400UM, Memmert) for 16 h.