Properties of extremely high molecular weight polystyrene in solution

Abstract Extremely high molecular weight polystyrenes with a M w in the range 10.8 × 10 6 to 2.2 × 10 7 were prepared by emulsion polymerization initiated with a heterogeneous initiator at 30°C, which has a ‘living character’. Samples of polystyrene were characterized by light scattering and viscometry in toluene and benzene at 25°C, and in θ-solvent cyclohexane at 34.8°C. Also determined were the relationships of mean-square radius of gyration 〈 s 2 〉 (m 2 ) and the second virial coefficient A 2 (m 3 mol kg −2 ) on the molecular weight, which for toluene and benzene are described in equations: Toluene (25°C) 〈s 2 〉=1.59 × 10 −23 M w 1.23 ; A 2 =4.79 × 10 −3 M w −0.63 ; Benzene (25°C) 〈s 2 〉=1.23 × 10 −22 M w 1.20 ; A 2 =2.59 × 10 −3 M w −0.59 . The parameters in the Mark-Houwink-Sakurada equation were established, for extremely high molecular weight polystyrene in toluene and in benzene, at 25°C into the form giving for [η] ( m 3 kg −1 ): [η] = 8.52 × 10 −5 M w 0.61 ; [η] = 1.47 × 10 −4 M w 0.56 . The mentioned relations, as well as the obtained values of Flory parameter ∅ 0 and of ratio [η] M w 0.5 were compared with solution properties of high molecular weight polystyrene with narrow molecular weight distribution prepared by anionic polymerization by Fukuda et al .