Complex sentence: He showed that vinyl monomers tend to add to the growing polymer in a head-to-tail fashion and his work on the low-temperature copolymerization of butadiene and styrene was important to the commercial production of synthetic rubber.
Split into simpler sentences: He showed that vinyl monomers tend to add to the growing polymer in a head-to-tail fashion. His work on the low-temperature copolymerization of butadiene and styrene was important to the commercial production of synthetic rubber.