Carbon fiber reinforced polymer as epoxy, but other thermoset or thermoplastic polymers, such as polyester, vinyl ester, or nylon, are sometimes used. The composite material may contain aramid (e.g. Kevlar, Twaron), ultra-high-molecular-weight polyethylene (UHMWPE), aluminium, or glass fibers in addition to carbon fibers. The properties of the final CFRP product can also be affected by the type of additives introduced to the binding matrix (resin). The most common additive is silica, but other additives such as rubber and carbon nanotubes can be used. The material is also referred to as "graphite-reinforced polymer" or "graphite fiber-reinforced polymer" ("GFRP" is less common, as it clashes with
Sometimes I'm Happy (Sometimes I'm Blue) a duet by Baur and Gladys Rice on Columbia Records (catalog number 998-D) and a vocal by Vaughn De Leath on Brunswick Records (catalog number 3608) also had a significant degree of popularity. A number of other recordings were made in 1927 (see below), and the tune has become a standard, recorded by many artists since that time. It appeared as the B-side of the landmark 1935 recording of "King Porter Stomp" by Benny Goodman and his orchestra (released July 31 as Victor 25090). Sometimes I'm Happy (Sometimes I'm Blue) "Sometimes I'm Happy" is a popular song. The music was