Bricks, Masonry, Asphalt and Concrete - Epoxy for holding rebar?

I am joining a new concrete pad(12'x16') to an existing pad(12'x16') by drilling holes in the old pad to fit rebar into. I have seen in other posts that I should use an epoxy in these holes instead of relying on the concrete to fill them in. What kind of epoxy would this be and where could I buy it?

One of the box stores will have it. Its a 2 part epoxy in a tube for your caulk gun. The stuff I have is Sika Contractors Choice Anchoring Adhesive. I think its from Home Depot.

Beware, this stuff is mean. If you are using this indoors, you will be high in no time. You want to prep all the holes a head of time. Get a few rocks and shims to stick under the rebar to hold it level. Inject and install the rebar, level with the rocks or shims and get lost while it cures. I highly recommend using a large fan to exhaust the fumes if using this indoors or a confined space.

Another option is to forego the use of epoxy altogether. When you drill the holes for the rebar, use the proper bit (1/2 inch bit for #4 rebar, 3/8 bit for #3, etc.) The rebar will be so snug that it will go into the hole only if it is driven in with a hammer. You will not be able to pull it out no matter how hard you try. It's purpose is only to keep the slabs at the same level vertically, not to hold them together horizontally, so they really don't need to be epoxied at all. One slab won't be able to settle without the adjacent one going with it.

Pecos