“…In this series one of our aims is to provide -besides accurate p VT-data -information about the influence of pressure on phase transitions. The first five papers dealt with PE [1,3,4], PEO [1], PP [1,2], poly(trans-l,4-butadiene) [5] and n-alkanes [4]. Now we have chosen poly(1-butene), (-CH2-CHC2Hs-),, subsequently called simply polybutene, as the topic of the present study for the two following reasons.…”