Popular Blockchain Projects Using Layer 2 Scaling

Ethereum 2.0
Polygon (Matic Network, Layer 2 scaling for Ethereum )
Loopring (A scalable zkRollup Exchange and Payment Protocol)
Harmony (Interoperable layer 2 scaling for Ethereum)
OMG network (Layer 2 scaling solution)
PolkaDot (Sharding & Parachain Based)