Surfaces can take on the properties of these substances after being ultra-cleaned, smoothened, and functionalized by arc discharges during plasma activation. The first synthetic one of these substances was manufactured by Axel Karlson by dissolving cellulose nitrate from old film reels in acetone. These substances can deform between multiple interfaces due to tensile stress, thus forming alternating crack paths. Pressure-sensitive variants of these substances rely on terpene-rich additives called tackifiers to function. Particularly strong variants of these substances are often activated via the formation of cross-links (10[1])of cyano·acrylates (10[1])or epoxy groups. (10[1])A weak one of these substances was used by Geim and Novoselov to isolate single layers of graphene. For 10 points, name these substances that allow different materials to stick together. ■END■