摘要 |
An aqueous dispersion is claimed which is capable of forming a free-standing, coherent, elastomeric, solid film which, after drying and annealing at 80 DEG C. for 30 minutes, demonstrates a tensile strength of about 11.0 MPa or greater wherein the dispersion comprises: I. an organic phase comprising: (a) one or more block copolymer(s) corresponding to the formula A-B-Xm-(B-A)n, wherein each A polymer block consists essentially of a monovinylidene aromatic monomer, having a weight average molecular weight from about 8,000 to about 15,000 Daltons, each B polymer block consists essentially of a conjugated diene and, optionally, a monovinylidene aromatic monomer having a weight average molecular weight from about 30,000 to about 200,000 Daltons, X is the remnant of a multifunctional coupling agent, m is 0 or 1, and n is an integer from 1 to 5, and (b) optionally, an extender for the block copolymer which is compatible with the B block; II. a surfactant; and III. water, wherein the A block effective phase volume in the organic phase is from about 5 to about 20 percent.
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