Abstract: Isotactic-polypropylene-based copolymers having a homogenous distribution of recurring units of formula (1): where R is a hydrogen, halide radical or a hydrocarbyl radical optionally containing an atom selected from oxygen, nitrogen, sulphur, phosphorus and silicon, and n is an integer ranging from 1 to 3; said copolymer having a 13C-NMR spectrum wherein the resonance signals attributed to the links between different monomeric units fall around 30, 34, 35, 45 and 47 ppm and present intensities at least two times higher than the resonance signals attributed to styrene—styrene sequences around 41 ppm and 44-46 ppm; a process for preparing said copolymers carried out in the presence of homogeneous catalytic systems comprising a metallocene compound and a cocatalyst; functionalized copolymers obtained from said isotactic-polypropylene-based copolymers; and graft copolymers comprising said isotactic-polypropylene-based copolymers as backbones.

Abstract: Isotactic-polypropylene-based copolymers having a homogeneous distribution of recurring units of formula (1) where R is a hydrogen, halide radical or hydrocarbyl radical optionally containing an atom selected from oxygen, nitrogen, sulphur, phosphorus and silicon and n is an integer ranging from 1 to 3; said copolymer having a 13C-NMR spectrum wherein the resonance signals attributable to the links between different monomeric units fall around 30, 34, 35, 45 and 47 ppm and present intensities at least two times higher than the resonance signals attributable to styrene-styrene sequences around 41 ppm and 44-46 ppm. A process for preparing said copolymers carried out in the presence of homogeneous catalytic systems comprising a metallocene compound and a cocatalyst. Functionalized copolymers obtainable from said isotactic-polypropylene-based copolymers. Graft copolymers comprising said isotactic-polypropylene-based copolymers as backbones.

Abstract: Semicrystalline manufactured articles made of syndiotactic poly-p-methylstyrene (s-PpMS) in a crystalline form having a high melting point (225.degree. C.), and processes for the preparation thereof. Processes for preparing semicrystalline manufactured articles (semi-finished products, formed articles, fibers, films, etc.) made of s-PpMS in its different crystalline forms by exposure of amorphous manufactured articles to suitable solvents and by subsequent thermomechanical treatments.