초록 ▼

A bulk polymerization process for free radical polymerization of vinyl monomers in a wiped surface reactor is disclosed. Referring to FIG. 1; monomer streams 5 (after purification and silica gel column 2) and 7 are combined with free radical initiator 9 to form a premix 16. Pump 18 transfers the pre

A bulk polymerization process for free radical polymerization of vinyl monomers in a wiped surface reactor is disclosed. Referring to FIG. 1; monomer streams 5 (after purification and silica gel column 2) and 7 are combined with free radical initiator 9 to form a premix 16. Pump 18 transfers the premix stream 22 through static mixer 24 into a wiped surface reactor 27. The reactor can be a counter rotating twin screw extruder which produces polymer stream 36 without the need of solvent and using residence times much shorter than prior art solution or emulsion processes. Some unique pressure sensitive adhesive acrylate polymers have been produced. They are believed to have a relatively high degree of branching. The bulk polymerization process permits the manufacture of pressure sensitive adhesive articles by extruding directly from the twin screw extruder onto a substrate.

대표청구항 ▼

A process of making a pressure sensitive adhesive composition by bulk polymerizing one or more free radical polymerizable vinyl compounds which comprises: (a) continuously feeding to a wiped surface reactor comprising a vessel and at least one rotor inside the vessel having a wiping portion located

A process of making a pressure sensitive adhesive composition by bulk polymerizing one or more free radical polymerizable vinyl compounds which comprises: (a) continuously feeding to a wiped surface reactor comprising a vessel and at least one rotor inside the vessel having a wiping portion located close to the inside surface of the vessel and a root portion spaced substantially further from the inside surface than the wiping portion wherein the root surface is wiped continuously during rotation of the rotor raw materials which comprise unpolymerized vinyl compounds without any substantial amount of polymerized vinyl compounds, and at least two initiators for free radical polymerization under the following conditions: (i) all raw materials being fed substantially free of oxygen, and (ii) at least one monomer being a liquid unpolymerized vinyl compound having a viscosity less than about 4,000 centipoise which is fed under a pressure at least as high as the vapor pressure of the combined raw materials at the temperature to which the exotherm of the free radical polymerization brings them in the reactor; (b) reacting the raw materials to desired conversion; and (c) continuously withdrawing a polymeric material from the reactor.