Pittsburgh sent a second-round pick this year and prospect Danny Kristo to Carolina in the trade.
Daley injured his knee during the first period of Pittsburgh's 3-1 win over Carolina on Tuesday and required arthroscopic surgery. The 33-year-old Daley has 19 points and is a plus-9 this season.
Carolina will retain 50 percent of Hainsey's salary. Hainsey becomes an unrestricted free agent July 1.
Hainsey, 35, is in his 14th season in the league and fourth with the Hurricanes. The Connecticut native has 14 points but is a minus-14 on the season.
The 6-foot-3 left-handed defenseman led the Hurricanes with 79 hits, was third in ice time and third in blocked shots. He has missed only three games since the 2012-13 season.
The Penguins made some shrewd blueline moves last season on the way to winning the Stanley Cup. They brought in Daley from Chicago and Justin Schultz from Edmonton. Both were struggling with their respective teams but made a solid impact with the Penguins.