Gluing rubber to PVC can be challenging because of the tendency of both products to react badly to general adhesives, often melting upon adhesive application or not bonding at all. Finding the proper adhesive, however, simplifies the process, allowing you to create tight bonds that last without temperature changes, or moisture weakening the bond enough to cause failure.
Clean the surfaces of both the rubber and PVC items to rid the material of any contaminants that can interfere with the adhesive. Fill a bucket with warm water and then add enough mild liquid soap to create suds when mixed. Dip a sponge into this mixture and use the sponge to clean the surfaces. Rinse with clean water and pat the surfaces dry with a clean piece of cloth.
Apply a layer of primer to the surfaces of the PVC and the rubber with the primer pen contained in the plastics glue kit. Spread the primer over any portion of the surface that you intend to glue, creating an intermediate layer of material between the PVC and rubber and the plastics glue to create a better adherence surface.
Open the seal on the end of the plastics glue tube with a nail, and then screw the glue nozzle onto the tip of the tube.
Pop the cap off the end of the glue tube nozzle and place a bead of glue in a line across either the PVC or rubber surface. Press the second surface onto the first along the glue line with a light amount of pressure. Hold the two in place for about 30 seconds to allow the glue to bind the two surfaces together. Release the items and allow them to sit in place for 30 minutes to give the glue time to cure.
Clean the tip of the glue nozzle with a paper towel, replace the cap, and then store the glue in a dry cool area for the next time you need it, with the nozzle pointed upwards to prevent glue from clogging the tube.