Styrene block copolymers (SBCs) offer cohesion, strength, and heat resistance for both pressures sensitive adhesives (PSAs) and non-pressure sensitive adhesives. The styrene phase forms a physically crosslinked network in the adhesive at room temperature. Of the SBCs, styrene butadiene styrene has the highest shear strength and moderately good peel strength.
Some of the advantages of SBCs in solvent borne adhesives and sealants are:
Polymers are directly soluble: no milling necessary
Solution times are shorter: greater productivity and efficiency
Solutions are more uniform: better control and reproducibility
A typical high strength solvent based styrene butadiene styrene pressure sensitive adhesive is provided above. It can be used for tapes and labels and general purpose applications. Open time, or the time between application of the adhesive coating and mating of the substrates, is an important parameter in PSA solvent-based adhesives. High melting styrene block copolymer resins may improve the temperature resistance of the adhesive, but their incorporation usually decreases the open time.
