| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a copolymer latex for an adhesive reduced in loss of cord strength after high-temperature vulcanization and being excellent in initial tack and heat-resistant adhesiveness by emulsion-polymerizing an aliphatic conjugated diene monomer with a vinylpyridine and other monomers copolymerizable therewith in a specified compositional ratio. SOLUTION: 40-75 wt.% aliphatic conjugated diene monomer (e.g. 1,3-butadiene) is mixed with 5-20 wt.% vinylpyridine (e.g. 2-vinylpyridine) and 5-55 wt.% (the total is 100 wt.%). The copolymer latex to be obtained is one wherein the content of toluene-insolubles of a dry film made therefrom is 40 wt.% or below, the weight-average molecular weight of tetrahydrofuran-soluble sol fraction of the film is 70,000 or above, and the weight-mean particle diameter of the latex is 80-180 nm, and the Moony viscosity is 130 or above. In the polymerization of the monomer mixture, an emulsifier, a chain transfer agent, a polymerization initiator, etc., can also be used.</p> |
