Synthesis of PS-b-PEG-b-PS Amphiphilic Triblock Copolymer by Atom Transfer Radical Polymerization (ATRP) Method and Investigation of Inhibitory Effect on Methane Gas Hydrate Formation

In this research, polystyrene-poly (ethylene glycol)-polystyrene (PS-b-PEG-b-PS) amphiphilic triblock copolymer was synthesized by atom transfer radical polymerization (ATRP) method. The results of FTIR and NMR analyses were confirmed the successful synthesis of the presented triblock copolymer. The experiments of hydrate inhibition performanc testing were carried out in the presence of methane gas using rocking-cell reactor at initial pressure of 68 bar and 1.5oC, respectively. The potential kinetic inhibitory effect of synthesized PS-b-PEG-b-PS copolymer was investigated at the conectrations of 0.05 and 0.1 wt% and compared with the similar data of commercial inhibitors including polyvinylpyrrolidone (PVP) and Luvicap EG as a polyvinylcaprolactam (PVCap)-based kinetic inhibitor from BASF. The obtained results showed that the synthesized PS-b-PEG-b-PS at concentration of 0.1% wt had about 92% inhibitory performance, while PVP as a commercial inhibitor had up to 84% inhibitory performance. Furthermore, the rate of gas consumption in the presence of the synthesized PS-b-PEG-b-PS was decreased about 6 times compared to Luvicap EG and 2 times less than to PVP one. The synthesized amphiphilic triblock PS-b-PEG-b-PS copolymer by ATRP method could be introduced as a new potential kinetic gas hydrate inhibitor.