Abstract: Shaped articles of polybut-1-ene are made by preheating a polymer blank in the crystalline form II at a temperature between 20.degree. and 90.degree. C. The preheated blank is then press-forged under a pressure between 8 and 100 kgf/mm.sup.2 for a period of 1-40 seconds. During the shaping operation, the polymer is converted into the crystalline form I. Polybut-1-ene shaped articles are formed that have a melting peak, determined by differential thermal analysis, at 119.degree. C.

Abstract: The present invention relates to a process for determining the rheological properties of fluid, consisting in completely filling a space located between a body constituted by a double cone of vertex angle 2.alpha.,.alpha. being smaller than 90.degree. and a biconical surface, of the same axis as the axis of said double cone, of vertex angle 2.beta.,.beta. being equal to or smaller than 90.degree., then said material is subjected to strains by driving said double cone or said biconical surface around the common axis. The non-driven element remaining fixed, said drive being effected with the aid of a device by which either a speed or a torque is imposed, according to a known program, on the driven element, and the parameter--speed or torque--which is not imposed is measured. The invention also relates to an apparatus for carrying out said process.

Abstract: Shaped articles of polybut-1-ene are made by preheating a polymer blank in the crystalline form II at a temperature between 20.degree. and 90.degree. C. The preheated blank is then press-forged under a pressure between 8 and 100 kgf/mm.sup.2 for a period of 1-40 seconds. During the shaping operation, the polymer is converted into the crystalline form I. Polybut-1-ene shaped articles are formed that have a melting peak, determined by differential thermal analysis, at 119.degree. C.

Abstract: A method for the accelerated transformation of the crystalline form of isotactic polybutene pipe, comprising moving the pipe linearly and subjecting the pipe while moving to a plurality of simultaneously inwardly directed radial stresses acting on the outer surface of the pipe along one or more radii of the same transverse cross section and in one or more adjacent cross sections of the pipe and apparatus for carrying out such method.