The Huskers have won five straight conference games for the first times since 1998-99 and have won eight conference games for the first time since 2008-09 when it was a member of the Big 12.
Nebraska took control of the game late in a low-scoring first half. With Purdue center A.J. Hammons on the bench, Nebraska went on a 7-0 run capped by a Petteway fast break layup to take a 21-14 lead and stretched that advantage to 30-20 on Shavon Shields' three-point play with 1:04 left in the first half.
Shields finished with 18 points and 10 rebounds for Nebraska and Walter Pitchford had 10.
Terone Johnson led Purdue with nine points.
The Boilermakers were held to just 30 percent shooting in the game and twice went more than 6 minutes without a field goal. The second drought came early in the second half.
After cutting the Nebraska lead to 39-30 with 17:43 remaining, Purdue made just one field goal in nearly 10 minutes against Nebraska's aggressive man-to-man defense.
Nebraska went up 63-38 on back-to-back dunks by Petteway and Walter Pitchford. Purdue got no closer than 21 until Nebraska coach Tim Miles cleared the bench with just over 2 minutes remaining.
The win was Nebraska's first regular-season win over Purdue since the Huskers joined the Big Ten and its first over the Boilermakers in Lincoln since 1994. Purdue defeated Nebraska 70-64 on Jan. 12.
Purdue made just one field goal in the final 8:26 of the first half. But the Boilermakers made all 12 of their first half free throws to stay close.