METHOD FOR SYNTHESIS OF SHOCK RESISTANT VINYLAROMATIC (CO) Russian patent published in 2010 - IPC C08F279/02 C08F291/02 

FIELD: chemistry.

SUBSTANCE: invention describes a method for synthesis of shock resistant vinylaromatic (co)polymers which are grafted onto an elastomer, containing a rigid matrix formed by vinylaromatic polymers or copolymers, and an elastomeric phase dispersed in the matrix in form of particles with strict bimodal distribution according to diametre, involving: 1) functionalisation of the first portion (X₁) of the elastomer using a functionalisation/polymerisation catalyst system formed by a free-radical polymerisation initiator (G) with number F of functional groups capable of pulling a proton from the polymer chain of the elastomer, and a stable free-radical polymerisation initiator (I) which contains a = N-O' group and a = N-O-R' group in molar ratio (I)/G·F between 1 and 3, where F is equal to the number of functional groups per molecule of the initiator, which gives two free radicals through decomposition, R' is a C₁-C₆ (iso)alkyl radical or a C₇-C₂₀ arylalkyl radical, possibly containing heteroatoms; 2) mixing the functionalised elastomer with the second portion (X₂) of the elastomer for a period of time sufficient for obtaining a homogeneous composition; 3) addition of the homogeneous elastomer composition to a liquid phase essentially formed by a mixture of vinylaromatic monomer and a polymerisation solvent with weight ratio from 60/40 to 100/0 and ratio (X₁+X₂)/vinylaromatic monomer greater than or equal to 8/92; 4) polymerisation of the vinylaromatic monomer, possibly in the presence of one or more comonomers at temperature higher than or equal to 120°C, 5) extraction of the obtained vinylaromatic polymer at the end of polymerisation; and 6) possible return of the mixture of solvent and monomer coming from the extraction process to step (1) after separation of possibly polar comonomers. The invention also describes a method for synthesis of shock resistant vinylaromatic (co)polymers which are grafted onto an elastomer, containing a rigid matrix formed by vinylaromatic polymers or copolymers, and an elastomeric phase dispersed in the matrix in form of particles with strict bimodal distribution according to diametre (versions).

EFFECT: obtaining an end product in which distribution of diametres of particles of a dispersed elastomeric phase is strictly bimodal.

14 cl, 12 dwg, 7 ex