| 摘要 |
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)/GF 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 120C, 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 |
