Shawcross started Stokes first game of the season, against Bolton, but after a nightmare match he was dropped the following week.
Despite this, Pulis expects the defender to still play to part in the Potters' battle against relegation.
"Ryan is a big part of what we are trying to do here," Pulis told the Stoke Sentinel. "I have great respect for Ryan as a person and for what he has achieved with us so far.
"There's no way he's leaving this football club in this (loan) window. At the end of the window we will obviously take stock of everything at the club, but I'm hoping Ryan will have shown the right spirit, character and work ethic to get back in the team.
"That's the challenge in front of him now and it's one I'm sure he will tackle with great relish because he's that kind of character."
"Also, we are still in the League Cup and need good competition for places at the club anyway. We are not going to let players go who are in or around the team. If you look at clubs now in the Premier League you'll see they have good players not in the team because you need big squads and strong competition."
Jim is desperate to add to his squad, and wants a left midfielder and a centre back.
It is understood Jim is looking at Boro's Chris Riggott, whom is currently out the first team picture at the Riverside, behind David Wheater and Robert Huth.
Riggott has had experience in the Championship, something which has persuaded Jim to try and prise the former England U-21 International away from the Britannia Stadium.
He spent last season on loan at Stoke where he was used along with Shawcross.
Jim hopes the attraction of first team football will be enough to acquire the player on an initial tempoary basis.
If a centre back is brought in he would play alongside Town Captain Gareth McAuley in the heart of defense, replacing Richard Naylor.