Viscoelastic properties of 1,2-,1,4- and 1,2-1,4-diblock butadiene polymers

The use of polar modifiers to produce novel structures of butadiene polymers is well documented in the literature [Antkowiak TA, Oberster AE, Halasa AF, Tate DP. J Polym Sci 1972;10:1319; Langer AW. Polym Prep Am Sco Polym Div. 1966;7:132; Hay JN, McCabe JF, Robb JC. Polym Prep Am Chem Faraday Trans 1972;1:681; Halasa AF, Mochel VD, Frankel G. Polym Prep Am Chem Sco, Div Polym Chem 1980;21(1):13; Halasa AF, Schulz DN, Tate DP, Mochel VD. Adv Organomet Chem 1980;8:55 [1–5]]. Manipulating microstructures of 1,3-butadiene to produce diblock co-polymers has been reported by one of us [Halasa AF. Rubber Chem Technol 1981;54:627 [6]]. The discovery of polar modifier di-piperdinoethane to produce pure (100%) atactic 1,2-polubutadiene [Halasa AF, Lohr DF, Hall JE. J Polym Sci Polym Chem Ed 1981;19 [7]] provided scientists with a new tool to structurally engineer various block co-polymers of butadiene and styrene and study their structural and viscoelastic properties [Cohen RE, Torradas JM. MS Thesis, MIT, May 1980, PhD Thesis, MIT January, 1982 [8]].