TWO-COMPONENT BLOCK COPOLYMERS Russian patent published in 2024 - IPC C08F297/04 C08F236/10 C08F4/48 C08L53/02 C08L9/06 C09J153/02 

FIELD: chemistry.

SUBSTANCE: present invention relates to compositions of two-component block copolymers, as well as to methods for production and use thereof in adhesive, bitumen compositions, sealant compositions, as well as in impact-resistant polystyrene resins and ABS resins. Two-component block copolymer composition contains C and U. C is a bound block copolymer containing repeating units from a conjugated diene monomer, block A₁ and the remainder of the binding agent. Block A₁ is obtained only from a monovinyl aromatic monomer and is bonded to a binding agent. C has outer end portions rich in conjugated diene monomer. U is an unbound block copolymer containing repeating units of a conjugated diene monomer and a terminal block A₂. Block A₂ is obtained only from monovinyl aromatic monomer. Polymer block A₂ has a higher molecular weight than polymer block A₁. U has a lower molecular weight and a higher content of monovinyl aromatic repeating units than C. C makes 20 to 80% of molecular weight distribution. Method of producing the composition involves copolymerisation of a conjugated diene monomer and a monovinyl aromatic monomer in the presence of an organolithium initiator and a hydrocarbon solvent to obtain polymer anions; deactivation of a portion of the polymer anions by reaction with a binding agent; optional deactivation of part of polymer anions by reaction with proton-donor compound or electrophilic agent of chain termination; block copolymerisation of an additional amount of monovinyl aromatic monomer with the remaining portion of the polymer anions; deactivation of polymer anions by reaction with a proton-donor compound, an electrophilic monofunctional compound or a mixture thereof; extraction of two-component block copolymer. Obtained compositions demonstrate favourable efficiency when producing microporous cross-linked rubber mixtures and hot-melt pressure-sensitive adhesives. Articles made from cross-linked microporous rubber mixtures made from compositions of two-component block copolymers have a lower density, a smaller and more homogeneous pore size, higher softness and elasticity than block copolymers of the prior art, and also have excellent appearance without defects in the form of bubbles.

EFFECT: hot-melt pressure-sensitive adhesives containing compositions of two-component block copolymers, very well suited for labels, demonstrating higher adhesiveness and higher softening point than adhesives obtained from block copolymers of prior art.

40 cl, 9 dwg, 10 tbl, 27 ex